Bovine ticks harbour a diverse array of microorganisms in Pakistan

Helminth infection in wild boars in Primorye, Russia

Wild boars have a worldwide distribution and also have major economic, veterinary, and medical importance. Due to a small amount of data on the parasitic fauna of wild boars in the Russian Far East, especially in Prymorye territory, a post-mortem parasitic examination of 20 wild boars was provided. The general prevalence was 25%, and a total of six helminth species, including one larva stage, were found. The most prevalent helminth species were Gnathostoma doloresi (25%) and Metastrongylus elongatus (20%). Followed by Trichuris suis and Ascaris suum (15%). The lowest prevalence was registered for Cysticercus tenuicollis (the larvae stage of T. hydatigena). Parasites were found in each region, with the highest prevalence registered in the Chuguevskii region. Totally 100% of adult boars were positive for helminth infections, instead of 60% of young specimens. Some helminthes found (G. doloresi, T. suis, A. suum) have zoonotic potential and can be involved in the circulation of human parasitic diseases, especially in rural areas. Further research work on parasitic infections in wild boars in Prymorye is necessary due to the high prevalence of helminthes in wild boars.

Molecular epidemiology and multilocus genotyping of Giardia duodenalis in individuals attending major public hospitals in Shiraz, southwestern Iran: A public health concern

Giardia duodenalis is one of the most common causes of waterborne disease worldwide, and is often associated with outbreaks of diarrhea in areas with poor sanitation and hygiene. This study aimed to assess the prevalence and genetic diversity of G. duodenalis assemblages in individuals attending major public hospitals in Shiraz, southwestern Iran. From August 2022 to May 2023, a total of 614 stool samples from individuals were collected and initially examined for G. duodenalis cysts using parasitological techniques, sucrose flotation, and microscopy. Microscopy-positive samples were validated by SSU-PCR amplification of the parasite DNA. A multilocus genotyping (MLG) scheme, which focused on the triose phosphate isomerase (tpi) and the glutamate dehydrogenase (gdh) genes, was employed for genotyping purposes. G. duodenalis cysts were found in 7.5% (46/614) and 8.5% (52/614) of samples through microscopy and SSU-PCR, respectively. Successful amplification and sequencing results were obtained for 77.3% (17/22) and 45.5% (10/22) of the infected samples at the tpi and gdh loci, respectively. MLG data for the two loci were available for only five samples. Out of the 22 samples genotyped at any loci, 54.5% (12/22) were identified as assemblage A, while 45.5% (10/22) were identified as assemblage B. AII was the most predominant sub-assemblage identified [54.5% (12/22)], followed by BIII [27% (6/22)], discordant BIII/BIV [13.6% (3/22)], and BIV [4.5% (1/22)]. In the present study, no assemblages suited for non-human animal hosts (e.g., C-F) were detected. This suggests that the transmission of human giardiasis in Shiraz is primarily anthroponotic. Further molecular-based analyses are necessary to confirm and expand upon these findings. These analyses will also help determine the presence and public health importance of the parasite in environmental samples, such as drinking water.

Marked genetic diversity within Blastocystis in Australian wildlife revealed using a next generation sequencing-phylogenetic approach

Blastocystis is a genus of intestinal stramenopiles that infect vertebrates, and may cause disease of the alimentary tract. Currently, at least 40 genotypes ("subtypes") of Blastocystis are recognised worldwide based on sequence data for the small subunit of the nuclear ribosomal RNA (SSU-rRNA) gene. Despite the numerous studies of Blastocystis worldwide, very few studies have explored Blastocystis in wild animals, particularly in Australia. Here, we used a PCR-based next generation sequencing (NGS)-phylogenetic approach to genetically characterise and classify Blastocystis variants from selected wildlife in the Australian state of Victoria. In total, 1658 faecal samples were collected from nine host species, including eastern grey kangaroo, swamp wallaby, common wombat, deer, European rabbit, canines and emu. Genomic DNA was extracted from these samples, a 500 bp region of the SSU-rRNA gene amplified by polymerase chain reaction (PCR) and, then, a subset of samples sequenced using Illumina technology. Primary PCR detected Blastocystis in 482 of the 1658 samples (29%), with the highest percentage in fallow deer (63%). Subsequent, Illumina-based sequencing of a subset of 356 samples revealed 55 distinct amplicon sequence variants (ASVs) representing seven currently-recognised subtypes (STs) [ST13 (prominent in marsupials), ST10, ST14, ST21, ST23, ST24 and ST25 (prominent in deer)] and two novel STs (ST45 and ST46) in marsupials. Mixed infections of different STs were observed in macropods, deer, emu and canids (fox, feral dog or dingo), but no infection was detected in rabbits or wombats. This study reveals marked genetic diversity within Blastocystis in a small number of species of wild animals in Australia, suggesting complexity in the genetic composition and transmission patterns of members of the genus Blastocystis in this country.

Molecular identification, risk factor assessment, and phylogenetic analysis of tick-borne pathogens in symptomatic and asymptomatic cattle from South-Eastern Iran

Tick-borne pathogens (TBPs) represent a substantial threat to cattle globally, exerting adverse impacts on production, health, and economic viability. This study delves into the prevalence and implications of TTBPs in cattle sourced from resource-limited smallholder livestock farms situated in southeastern Iran, proximate to Afghanistan and Pakistan. Blood and tick specimens were systematically collected from a cohort of 230 cattle, comprising 150 asymptomatic and 80 symptomatic individuals. Genomic DNA isolated from blood samples underwent rigorous examination for the presence of key TBPs, including Anaplasma marginale, A. phagocytophilum, A. bovis, A. centrale, Babesia bigemina, and Theileria annulata, utilizing multiple genetic markers. Nucleotide sequence analysis facilitated the reconstruction of phylogenetic relationships. The study also evaluated various potential risk factors, such as clinical status, gender, age, breed, tick infestation, and management practices, to elucidate their associations with TTBPs. Among the cattle cohort, a staggering 87.8% (202/230) tested positive for at least one pathogen. Prevalence statistics encompassed A. marginale (72.2%), T. annulata (68.3%), A. phagocytophilum/A. platys-like complex (66.1%), A. centrale (16.7%), B. bigemina (10.0%), and A. bovis (6.1%). Remarkably, mixed infections involving two, three, and four pathogens were detected in 23%, 52.1%, and 2.2% of animals, respectively. Notably, all asymptomatic cattle were positive for at least one TBP. Tick infestation was observed in 62.2% (143/230) of cattle, predominantly caused by Hyalomma anatolicum (82.5%), Rhipicephalus (Boophilus) annulatus (13.1%), and R. sanguineus sensu lato (4.4%). Risk factors linked to TBPs encompassed tick infestation, older age, and crossbred animals. Clinical presentations among symptomatic cattle encompassed fever, anemia, weight loss, anorexia, jaundice, and enlarged superficial lymph nodes. This study underscores the pivotal role of asymptomatic carriers in the propagation of TTBPs within endemic regions. Furthermore, it emphasizes the potential for the implementation of molecular diagnostics to unmask subclinical infections, thereby affording the opportunity for targeted interventions aimed at ameliorating the burden of TTBPs in resource-constrained smallholder dairy farms.

Irritant and repellent behaviors of sterile male Aedes aegypti (L.) (Diptera: Culicidae) mosquitoes are crucial in the development of disease control strategies applying sterile insect technique

The mosquito Aedes aegypti, known to transmit important arboviral diseases, including dengue, chikungunya, Zika and yellow fever. Given the importance of this disease vector, a number of control programs have been proposed involving the use of the sterile insect technique (SIT). However, the success of this technique hinges on having a good understanding of the biology and behavior of the male mosquito. Behavioral responses of Ae. aegypti male populations developed for SIT technology were tested under laboratory conditions against chemical and natural irritants and repellents using an excito-repellency (ER) chamber. The results showed that there were no significant behavioral escape responses in any of the radiation-sterilized male Ae. aegypti test populations when exposed to citronella, DEET, transfluthrin, and deltamethrin, suggesting that SIT did not suppress the expected irritancy and repellency (avoidance) behaviors. The type of information reported in the current study is vital in defining the effects of SIT on vector behavior and understanding how such behavior may influence the success of SIT technology with regard to other vector control interventions.

Analysis of Achyranthes aspera leaf extract and acute toxicity study on fingerlings of Nile tilapia, Oreochromis niloticus

Schistosomiasis is a debilitating chronic disease with great socioeconomic and public health impact affecting the poor rural populations who lack access to sanitation, and safe water supply. The high cost of synthetic molluscicides, their toxicity to non-target organisms, and their persistence in the environment have forced the research of plant-derived molluscicides. Although plant molluscicides are cheap, biodegradable, ecofriendly and less toxic to higher animals, unregulated applications could affect non-target organisms. Therefore, ecotoxicological studies are essential to assess the toxicity of these substances to economically and ecologically significant fish species and to establish safe dosage level. This study is intended to investigate the acute toxicity of a molluscicidal plant Achyranthes aspera to Nile tilapia fingerlings, Oreochromis niloticus (O. niloticus) (n = 7) were exposed to serial dilutions of A. aspera leaf aqueous extract using maceration method for 96 h in triplicate setup. Phytoconstituents were identified by GC-MS. Mortality data were analyzed by probit regression to determine lethal concentrations. The NOAEC was ascertained through hypothesis testing based on survival data. The respective piscicidal LC1 and LC10 values were 897.43 and 1063.87 mg/L while the LC50 is 1310.74 mg/L. In addition, the NOAEC was 1100 mg/L (p > 0.05). This piscicidal toxicity is much lower than its molluscicidal potency may be due to the presence of rotenones and triterpenoides which are commonly found in piscicidal natural products. The GC-MS analysis revealed 12 phytoconstituents including a monoterpene. This study indicates that A. aspera has low toxicity to Nile tilapia could be due to monoterpenes are nontoxic. The findings of this study demonstrate that, at this dose, the plant is safe to the test fish. Thus it can be effective, eco-friendly and sustainable alternative for the development of molluscicides for snail control.

Distribution of different Rickettsia species in countries of the WHO Eastern Mediterranean (WHO-EMRO) region: An overview

SUBJECT

Rickettsia is a zoonotic bacterial pathogen transmitted by vectors and has extensive reservoirs in animal and human populations. Rickettsiosis is a public health problem all over the world. However, comprehensive information on the geographical distribution of different Rickettsia species, infection status of reservoirs, vectors, and human cases is lacking in most parts of the world. Therefore, this study aimed to investigate the geographical distribution of different Rickettsia species and their vectors in countries of the WHO-EMRO region.

METHODS

In this review study, a search was conducted for reports and published studies on Rickettsia species from WHO-EMRO region countries in various databases from 1995 to 2022. Finally, the reported status of human cases, reservoirs, and vectors associated with each species in different countries was documented.

RESULTS

Reports of infections related to the detection of Rickettsia species were only available for 15 out of 22 WHO-EMRO member countries. A total of twenty-four Rickettsia species, including R. sibrica, R. lusitaniae, R. africae, R. prowazekii, R. felis, R. typhi, R. rickettsii, R. aeschlimannii, R. conorii, R. massiliae, R. helvetica, R. monacensis, R. rhipicephali, R. bellii, R. asembonensis, R. hoogstraalii, R. andeanae, R. raoultii, R. asiatica, R. slovaca, R. australis, R. barbariae, Candidatus R. amblyommii, and Candidatus R. goldwasserii, were reported from WHO-EMRO member countries. Furthermore, human cases infected with six different Rickettsia species, including R. sibrica, R. prowazekii, R. felis, R. typhi, R. rickettsii, R. aeschlimannii, R. conorii, R. massiliae, and R. helvetica, were reported from these countries.

CONCLUSION

The vast diversity of Rickettsia vectors has contributed to the ongoing discovery of new Rickettsia species. Therefore, further research on the reservoir hosts of Rickettsia infections in the understudied WHO-EMRO region is crucial. This research sheds light on Rickettsia disease's epidemiology and transmission dynamics in this region.

Novel insights regarding the safety and efficacy of pyrethroid-coated nanoparticles against Hyalomma ticks

Nanoparticles have been shown to inhibit major life cycle stages of ticks, indicative of the promising application of nanomaterials against hard ticks. The study thus probed into one of the alternative options to curtail Hyalomma by employing nanocomposites consisting of pyrethroids (cypermethrin and deltamethrin) coated nanoparticles of iron oxides and iron sulfides keeping alongside the evaluation of their toxicity through plant and mammalian cell lines. The nanoparticles used in this study were roughly spherical in morphology and exhibited various size dimensions upon characterization using SEM, EDX, and FTIR. The application of nanomaterials on female ovipositioning tick showed a decline up to 15% (females ovipositioned) in deltamethrin-coated FeO NPs, whereas this decline was up to 18% in Cyp-FeS NPs and up to 5% in Cyp-FeO NPs. Similarly, the larval hatching was also impacted, leading to a hatching percentage of 5% and only 1% by application of Cyp-FeS NPs and Cyp-FeO NPs, respectively. Similarly, the larval groups had LC90 of 4.1 and 4.73 mg/L for the Cyp-FeO NPs and Cyp-FeS NPs groups. The delta-FeO NPs and delta-FeS NPs demonstrated a promising effect against adult ticks, showing LC50= 3.5 mg/L, LC90= 6.7 mg/L and LC50= 3.8 mg/L, LC90= 7.9 mg/L, respectively. MTT assay revealed that the pyrethroids coupled with iron oxide nanoparticles showed the least cytotoxicity even at the highest concentration (10-1 µL) among other nanomaterials. The study thus concluded a safer spectrum of non-target effects of pyrethroids-coated nanomaterials in addition to their significant anti-tick activity.

Microfluidic PCR and network analysis reveals complex tick-borne pathogen interactions in the tropics

BACKGROUND

Ixodid ticks, particularly Rhipicephalus sanguineus s.l., are important vectors of various disease-causing agents in dogs and humans in Cuba. However, our understading of interactions among tick-borne pathogens (TBPs) in infected dogs or the vector R. sanguineus s.l. remains limited. This study integrates microfluidic-based high-throughput real-time PCR data, Yule's Q statistic, and network analysis to elucidate pathogen-pathogen interactions in dogs and ticks in tropical western Cuba.

METHODS

A cross-sectional study involving 46 client-owned dogs was conducted. Blood samples were collected from these dogs, and ticks infesting the same dogs were morphologically and molecularly identified. Nucleic acids were extracted from both canine blood and tick samples. Microfluidic-based high-throughput real-time PCR was employed to detect 25 bacterial species, 10 parasite species, 6 bacterial genera, and 4 parasite taxa, as well as to confirm the identity of the collected ticks. Validation was performed through end-point PCR assays and DNA sequencing analysis. Yule's Q statistic and network analysis were used to analyse the associations between different TBP species based on binary presence-absence data.

RESULTS

The study revealed a high prevalence of TBPs in both dogs and R. sanguineus s.l., the only tick species found on the dogs. Hepatozoon canis and Ehrlichia canis were among the most common pathogens detected. Co-infections were observed, notably between E. canis and H. canis. Significant correlations were found between the presence of Anaplasma platys and H. canis in both dogs and ticks. A complex co-occurrence network among haemoparasite species was identified, highlighting potential facilitative and inhibitory roles. Notably, H. canis was found as a highly interconnected node, exhibiting significant positive associations with various taxa, including A. platys, and E. canis, suggesting facilitative interactions among these pathogens. Phylogenetic analysis showed genetic diversity in the detected TBPs.

CONCLUSIONS

Overall, this research enhances our understanding of TBPs in Cuba, providing insights into their prevalence, associations, and genetic diversity, with implications for disease surveillance and management.

Real-Time Microfluidic PCRs: A High-Throughput Method to Detect 48 or 96 Tick-borne Pathogens in 48 or 96 Samples

Tick-borne pathogens (TBPs) are often detected through classical molecular tools (PCR, nested PCR, real-time PCR), but these are limited in terms of the number of targeted pathogens due to the volume of DNA available for analysis. To solve this problem, in 2014 we developed a new high-throughput method based on real-time microfluidic PCRs that can detect 48 or 96 pathogens in 48 or 96 samples in a single run, such as ten species from the Borrelia burgdorferi sensu lato group. We then used this technique for large-scale epidemiological studies of TBPs in tick and animal samples on an international scale through numerous collaborative projects.

Prevalence, clinical presentation, and therapeutic outcome of ectoparasitic infestations in dogs in Egypt

Background

Skin diseases are usually chronic in nature but not life-threatening. They affect the well-being and pose a threat to the general health of the affected animals.

Aim

This study aimed to investigate epidemiological, clinical, and therapeutic aspects of ectoparasitic infestations in dogs in a number of Egyptian governorates.

Methods

Ninety dogs (58 males and 32 females) aged from 1 month to 11 years from 6 Egyptian governorates were clinically examined during the years 2022 and 2023. Skin scraping samples were taken from all examined dogs, and deep ear swab specimens from five dogs suspected to have ear mites were obtained and parasitologically examined. Different ectoparasites were classified according to their morphological features. Twenty dogs were treated in four different patterns of administration of local, systemic, and supportive medications.

Results

The prevalence of ectoparasite infestation in examined dogs was 64% (58/90). The majority of ectoparasitic infestations (50/58) were single, while the rest (8/58) were mixed. Nine species of ectoparasites of fourtaxa were identified: a tick species (Rhipicephalus sanguineus); which had the highest prevalence among isolated ectoparasites from dogs (29%, 26/90), three flea species (Ctenocephalides canis, Ctenocephalides orientis, and Ctenocephalides felis) isolated from 18 out of 90 cases (20%), two types of dog chewing louse species (Trichodectes canis and Heterodoxus spiniger) isolated from 2/90 (2.2%) and three mite species: Demodex canis (18/90, 20%), Sarcoptes scabei var. canis (5/90, 6%) and Otodectes cynotis (2/90, 2.2%). The logistic regression analysis of the potential risk factors associated with the prevalence of ectoparasites in dogs revealed that age, breed, housing environment, habitat, and season were the significant factors affecting the prevalence of ectoparasites (p < 0.05) in contrast dog gender did not have a significant effect. Treated dogs showed variations in recovery times and dogs that received ancillary treatment showed rapid skin improvement and hair regrowth. Doramectin was effective against ticks and fleas, but fluralaner was more effective against Demodex mites.

Conclusion

The prevalence of ectoparasites in dogs in Egypt could be considered high and necessitates efforts toward accurate diagnosis, treatment, and control to reduce their impact on animal and public health.

Growth inhibitory effect of selected quinones from Indian medicinal plants against Theileria annulata

Tropical Bovine Theileriosis, caused by the protozoan parasite Theileria annulata, poses a significant threat to cattle populations. Currently, Buparvaquone is the sole effective naphthoquinone drug commercially available for its treatment. In our research, we delved into the potential of naturally occurring quinones as alternative treatments. We isolated two quinones, emodin and chrysophanol, from Rheum emodi Wall, and two more, embelin and lawsone, from Embelia ribes Burm.f. and Lawsonia inermis L. respectively. We assessed the anti-Theileria efficacy of these quinones in vitro using MTT and flow cytometric assays on T. annulata-infected bovine lymphocytes. Additionally, we evaluated their safety on uninfected bovine Peripheral Blood Mononuclear Cells (PBMC) and Vero cells. Emodin emerged as a promising candidate, exhibiting an IC50 value of 4 μM, surpassing that of buparvaquone. Emodin also displayed relatively low LD50 values of 1.74 mM against uninfected PBMC and 0.87 mM against Vero cells, suggesting potential safety. Remarkably, emodin demonstrated a high cell absorption rate of 71.32%. While emodin's efficacy and bioavailability are encouraging, further research is imperative to validate its safety and effectiveness for treating Tropical Bovine Theileriosis.

Mosquito Transposon-Mediated Transgenesis

Transposon-mediated transgenesis of mosquito vectors of disease pathogens followed the early success of transgenesis in the vinegar fly, Drosophila melanogaster The P transposable element used in Drosophila does not function canonically in mosquitoes, and repeatable, routine transgenesis in mosquitoes was not accomplished until new transposable elements were discovered and validated. A number of distinct transposons were subsequently identified that mediate the introduction of exogenous DNA in a stable and heritable manner in mosquito species, including members of the genera Aedes, Anopheles, and Culex The most versatile element, piggyBac, is functional in all of these mosquito genera, as well as in many other insects in diverse orders, and has been used extensively outside the class. Transposon-mediated transgenesis of recessive and dominant marker genes and reporter systems has been used to define functional fragments of gene control sequences, introduce exogenous DNA encoding products beneficial to medical interests, and act as "enhancer traps" to identify endogenous genes with specific expression characteristics.

Investigating intestinal parasitic infections with emphasis on molecular identification of Strongyloides stercoralis and Trichostrongylus colubriformis in north of Iran

Currently, parasitic infections are one of the important health problems in the world, especially in developing countries. This study aims to investigate intestinal parasites with an emphasis on molecular identification through the analysis of mitochondrial COX1 and ITS2 gene sequences of Strongyloides stercoralis (S. stercoralis) and Trichostrongylus spp. in north of Iran. Five hundred forty stool samples were collected from medical diagnostic laboratories affiliated with Mazandaran University of Medical Sciences in Sari city, north of Iran. First, all the samples were examined using direct smear, formalin-ether sedimentation, and trichrome staining technique. Suspected samples of Strongyloides larvae were cultured in agar plate. Then, DNA was extracted from samples containing Trichostrongylus spp. eggs and Strongyloides larvae. To amplify DNA, PCR was performed and the samples with a sharp band in electrophoresis were sequenced by Sanger method. Overall, the prevalence of parasitic infections in the study population was 5.4%. The highest and the lowest level of infection was observed with Trichostrongylus spp. and S. stercoralis at 3% and 0.2%, respectively. No traces of live Strongyloides larvae were seen in the culture medium of the agar plate. The six isolates obtained from the amplification of the ITS2 gene of Trichostrongylus spp. were sequenced, all of which were Trichostrongylus colubriformis. The sequencing results of COX1 gene indicated S. stercoralis. In the present study, the prevalence of intestinal parasitic infections in north of Iran has relatively decreased that its main reason can be due to the coronavirus epidemic and compliance with health principles. However, the prevalence of Trichostrongylus parasite was relatively high that it requires special attention to apply appropriate control and treatment strategies in this field.

Application of Cypermethrin-Coated ZnS and ZnO Nanoparticles against Rhipicephalus Ticks

Rhipicephalus ticks are described as important ticks impacting the costs of livestock rearing and by-products sale. The prevalence and response of ticks towards cypermethrin sprays indicate the need to implement the rational use of acaricides. In our previous studies, ZnO nanoparticles were shown to inhibit the major life-cycle stages of Hyalomma ticks, indicative of promising application of nanomaterials against the hard ticks. The current study was designed to probe into one of alternative options to curtail Rhipicephalus ticks by employing cypermethrin-coated nanoparticles of ZnO (C-ZnO NPs) and ZnS (C-ZnS NPs). The nanocomposites showed a roughly spherical type of morphology and various size dimensions upon characterization using SEM and EDX. Female ovipositioning was declined up to only 48% in ZnS and up to 32% in ZnO NPs even after 28 days in vitro. Similarly, the larval hatching was also impacted, leading to a hatching percentage of 21% and 15% by application of C-ZnS NPs and C-ZnO NPs, respectively. The LC₉₀ in female adult groups were 3.94 mg/L and 4.27 mg/L for the C-ZnO NPs and C-ZnS NPs groups, respectively. Similarly, the larval groups had LC₉₀ of 8.63 and 8.95 mg/L for the C-ZnO NPs and C-ZnS NPs groups. The study is a proof of the concept for incorporating effective and safe nanocomposites as acaricides. The studies on the efficacy and spectrum of non-target effects of nanomaterial-based acaricides can further refine the research on finding novel alternatives for tick control.

Evaluation of resistance of human head lice to pyrethroid insecticides: A meta-analysis study

Introduction

Pediculosis is one of the most common annoying infections caused by parasitic lice in humans. Pyrethroids are one of the main insecticides used to treat this infection. But recently, due to the Resistance of lice to this group of insecticides, its insecticidal effects have been affected. The present study was conducted through a meta-analysis to investigate the prevalence of pyrethroid resistance against these insecticides worldwide.

Methods

This study was conducted as a meta-analysis of the prevalence of treatment resistance in human head lice against pyrethroid insecticides worldwide. Based on this, all articles published without a time limit until the end of June 2022 in PubMed/MEDLINE, Web of Science (ISI), Scopus, and Google Scholar databases were extracted and using random-effects meta-analysis model statistical methods in the meta-analysis, Cochrane, Index I^2, and funnel plot were analyzed by STATA software.

Results

Twenty studies were included in the meta-analysis process. According to this, the prevalence of pyrethroid resistance insecticides in human head lice was estimated at 59% (CI95%: 50%-68%). Among pyrethroid insecticides, the highest prevalence of pyrethroid resistance against permethrin insecticide was 65%. Regarding the prevalence of Resistance by year, the prevalence before 2004 was estimated at 33%, but after 2015, this rate reached 82%. Also, the majority of pyrethroid resistance was estimated at 68% using genetic diagnosis methods and 43% using clinical diagnosis methods.

Conclusion

More than half of human head lice pyrethroid resistance insecticides. Based on this, it is recommended that before using this treatment method to treat human head lice Infestation, it should investigate the prevalence of pyrethroid resistance in that area, and if the majority of Resistance is high, alternative or combined treatment methods should be used.

Molecular prevalence and factors associated with Ehrlichia canis infection in dogs from the North Pantanal wetland, Brazil

Background and Aim

Canine monocytic ehrlichiosis is a vector-borne disease caused by the obligatory intracellular bacterium Ehrlichia canis, which is distributed across tropical and subtropical regions worldwide. Its prevalence within dog populations is high in municipalities located across the Pantanal biome, but it remains unknown in Barão de Melgaço, Mato Grosso, Brazil. This study aimed to determine the molecular prevalence and factors associated with E. canis infection in dogs domiciled in Barão de Melgaço.

Materials and Methods

A cross-sectional study was carried out to investigate the prevalence of E. canis infection in 369 dogs from urban and rural areas in Barão de Melgaço, North Pantanal wetland, Brazil. Initially, the dogs were examined, and, through a questionnaire, the risk factors were investigated. Blood samples were subjected to DNA extraction and PCR was performed to estimate the prevalence of E. canis infection.

Results

The molecular prevalence of E. canis infection in dogs was 42.5% and none of the studied variables were significantly associated with polymerase chain reaction (PCR) positivity (p > 0.05).

Conclusion

The high molecular prevalence demonstrates an increased transmission of the agent across the city. This also indicates that attention needs to be paid to E. canis infection and control measures should be introduced to prevent its transmission. The demographic and clinical risk factors commonly associated with E. canis infection in this study were not associated with PCR positivity.

Molecular epidemiology of Bartonella species from sympatric mammals collected in urban and rural areas of Punjab, Pakistan

Bartonella can infect a variety of mammals including humans and has been detected in the Americas, Europe, Africa, and Asia. Roughly two-thirds of identified Bartonella species are found and maintained in rodent reservoirs, with some of these species linked to human infections. Rodents (N=236) were caught from the Sahiwal division of Punjab, Pakistan and tested for Bartonella using PCR targeting gltA and rpoB genes, followed by sequencing of rpoB-positive samples. Genetic relatedness to other published Bartonella spp. rpoB gene sequences were examined using BLAST and phylogenetic analysis. Overall, 7.62% (18/236) of rodents were positive for both gltA and rpoB fragments. Rattus rattus and R. norvegicus had 7.94% (12/151) and 7.05% (6/85) positivity rates for Bartonella DNA, respectively. Phylogenetic analysis revealed a close relatedness between Bartonella spp. from Pakistan to Bartonella spp. from China, Nepal, and Malaysia. This study is the first reported detection of Bartonella spp. in R. rattus and R. norvegicus from the Sahiwal area of Punjab, Pakistan.

Density of Aedes aegypti (Diptera: Culicidae) in a low-income Brazilian urban community where dengue, Zika, and chikungunya viruses co-circulate

BACKGROUND

Low-income urban communities in the tropics often lack sanitary infrastructure and are overcrowded, favoring Aedes aegypti proliferation and arboviral transmission. However, as Ae. aegypti density is not spatially homogeneous, understanding the role of specific environmental characteristics in determining vector distribution is critical for planning control interventions. The objectives of this study were to identify the main habitat types for Ae. Aegypti, assess their spatial densities to identify major hotspots of arbovirus transmission over time and investigate underlying factors in a low-income urban community in Salvador, Brazil. We also tested the field-collected mosquitoes for arboviruses.

METHODS

A series of four entomological and socio-environmental surveys was conducted in a random sample of 149 households and their surroundings between September 2019 and April 2021. The surveys included searching for potential breeding sites (water-containing habitats) and for Ae. aegypti immatures in them, capturing adult mosquitoes and installing ovitraps. The spatial distribution of Ae. aegypti density indices were plotted using kernel density-ratio maps, and the spatial autocorrelation was assessed for each index. Visual differences on the spatial distribution of the Ae. aegypti hotspots were compared over time. The association of entomological findings with socio-ecological characteristics was examined. Pools of female Ae. aegypti were tested for dengue, Zika and chikungunya virus infection.

RESULTS

Overall, 316 potential breeding sites were found within the study households and 186 in the surrounding public spaces. Of these, 18 (5.7%) and 7 (3.7%) harbored a total of 595 and 283 Ae. aegypti immatures, respectively. The most productive breeding sites were water storage containers within the households and puddles and waste materials in public areas. Potential breeding sites without cover, surrounded by vegetation and containing organic matter were significantly associated with the presence of immatures, as were households that had water storage containers. None of the entomological indices, whether based on immatures, eggs or adults, detected a consistent pattern of vector clustering in the same areas over time. All the mosquito pools were negative for the tested arboviruses.

CONCLUSIONS

This low-income community displayed high diversity of Ae. aegypti habitats and a high degree of heterogeneity of vector abundance in both space and time, a scenario that likely reflects other low-income communities. Improving basic sanitation in low-income urban communities through the regular water supply, proper management of solid wastes and drainage may reduce water storage and the formation of puddles, minimizing opportunities for Ae. aegypti proliferation in such settings.

An Update of Evidence for Pathogen Transmission by Ticks of the Genus Hyalomma

Current and likely future changes in the geographic distribution of ticks belonging to the genus Hyalomma are of concern, as these ticks are believed to be vectors of many pathogens responsible for human and animal diseases. However, we have observed that for many pathogens there are no vector competence experiments, and that the level of evidence provided by the scientific literature is often not sufficient to validate the transmission of a specific pathogen by a specific Hyalomma species. We therefore carried out a bibliographical study to collate the validation evidence for the transmission of parasitic, viral, or bacterial pathogens by Hyalomma spp. ticks. Our results show that there are very few validated cases of pathogen transmission by Hyalomma tick species.

Low frequency of knockdown resistance mutation (L1014F) and the efficacy of PBO synergist in multiple insecticide-resistant populations of Anopheles gambiae in Ikorodu, Lagos State, Nigeria

Objective

We evaluated the susceptibility status of Anopheles gambiae in two communities of Ikorodu, Lagos, Nigeria to DDT, deltamethrin, lambda cyhalothrin and bendiocarb.

Methods

Anopheles immature stages were collected from their habitats in the surveyed community and allowed to emerge before exposure adult females to discriminating doses of WHO insecticides including DDT, deltamethrin, lambda cyhalothrin, bendiocarb and malathion. PBO synergistic bioassay was conducted for insecticides where the mosquito samples showed resistance. PCR assay was used for the detection of kdr mutation in the mosquitoes.

Results

Resistance to DDT (40% and 86%) and lambda cyhalothrin (75% and 84%) in Oke-Ota and Majidun respectively. Suspected resistance to deltamethrin (94.9%) and bendiocarb (93.5%) was recorded in Oke-Ota community and the mosquitoes were susceptible to malathion in both communities. KDR mutation (L1014F) from resistance samples from both locations though with a low frequency that significantly departs from Hardy-Weinberg's probability (P> 0.01). PBO synergized bioassay was able to increase knockdown, percentage mortality and restore full susceptibility to deltamethrin and bendiocarb.

Conclusion

Results from this study indicates that the metabolic resistance mechanism is highly implicated in the resistance to different classes of insecticide in Ikorodu and this should be taken into consideration when implementing vector control activities in this area.

The Surveillance of Borrelia Species in Camelus dromedarius and Associated Ticks: The First Detection of Borrelia miyamotoi in Egypt

Tick-borne diseases (TBDs) are emerging and re-emerging infections that have a worldwide impact on human and animal health. Lyme borreliosis (LB) is a severe zoonotic disease caused by the spirochete Borrelia burgdorferi sensu lato (s.l.) transmitted to humans by the bite of infected Ixodes ticks. Borrelia miyamotoi is a spirochete that causes relapsing fever (RF) and is genetically related to Borrelia burgdorferi s.l. However, there have been no reports of B. miyamotoi in Egypt, and the data on LB in camels is scarce. Thus, the present study was conducted to screen and genetically identify Borrelia spp. and B. miyamotoi in Egyptian camels and associated ticks using polymerase chain reaction (PCR).

METHODS

A total of 133 blood samples and 1596 adult hard ticks were collected from Camelus dromedaries at Cairo and Giza slaughterhouses in Egypt. Tick species were identified by examining their morphology and sequencing the cytochrome C oxidase subunit 1 (cox1) gene. Borrelia spp. was detected using nested PCR on the IGS (16S-23S) gene, and positive samples were genotyped using 16S rRNA and glpQ spp. genes specific for Borrelia burgdorferi and Borrelia miyamotoi, respectively. The positive PCR products were sequenced and analyzed by phylogenetic tree.

RESULTS

Analysis of the cox1 gene sequence revealed that the adult ticks belonged to three genera; Hyalomma (H), Amblyomma (Am), and Rhipicephalus (R), as well as 12 species, including H. dromedarii, H. marginatum, H. excavatum, H. anatolicum, R. annulatus, R. pulchellus, Am. testudinarium, Am. hebraeum, Am. lipidium, Am. variegatum, Am. cohaerens and Am. gemma. Borrelia spp. was found in 8.3% (11/133) of the camel blood samples and 1.3% (21/1596) of the ticks, respectively. Sequencing of the IGS (16S-23S) gene found that B. afzelii, detected from H. dromedarii and H. marginatum, and B. crocidurae, which belongs to the RF group, was detected from one blood sample. B. burgdorferi and B. miyamotoi were discovered in the blood samples and tick species. Phylogenetic analysis of the glpQ gene showed that the B. miyamotoi in this study was of the Asian and European types.

CONCLUSIONS

These results suggest that the camels can be infected by Lyme borrelia and other Borrelia bacteria species. This study also provides the first insight into the presence of Borrelia miyamotoi and B. afzelii DNA in camels and associated ticks in Egypt.

Diversity of Hepatozoon species in wild mammals and ticks in Europe

BACKGROUND

Hepatozoon spp. are tick-borne parasites causing subclinical to clinical disease in wild and domestic animals. Aim of this study was to determine Hepatozoon prevalence and species distribution among wild mammals and ticks in Europe.

METHODS

Samples of wild mammals and ticks, originating from Austria, Bosnia and Herzegovina, Croatia, Belgium and the Netherlands, were tested with PCR to amplify a ~ 670-bp fragment of the small subunit ribosomal RNA gene.

RESULTS

Of the 2801 mammal samples that were used for this study, 370 (13.2%) tested positive. Hepatozoon canis was detected in samples of 178 animals (3 Artiodactyla, 173 Carnivora, 1 Eulipotyphia, 1 Lagomorpha), H. martis in 125 (3 Artiodactyla, 122 Carnivora), H. sciuri in 13 (all Rodentia), Hepatozoon sp. in 47 (among which Hepatozoon sp. Vole isolate, all Rodentia) and H. ayorgbor in 4 (all Rodentia). Regarding origin, 2.9% (6/208) tested positive from Austria, 2.8% (1/36) from Bosnia and Herzegovina, 14.6% (173/1186) from Croatia and 13.9% (190/1371) from Belgium/the Netherlands. Of the 754 ticks collected, 0.0% (0/35) Hyalomma sp., 16.0% (4/25) Dermacentor spp., 0.0% (0/23) Haemaphysalis spp., 5.3% (24/50) Ixodes and 1.4% (3/221) Rhipicephalus spp. tested positive for Hepatozoon (4.2%; 32/754), most often H. canis (n = 22).

CONCLUSIONS

Hepatozoon canis is most present in mammals (especially in Carnivora such as gray wolves and golden jackals) and ticks, followed by H. martis, which was found merely in stone martens and pine martens. None of the rodent-associated Hepatozoon spp. were detected in the ticks, suggesting the possible implication of other arthropod species or non-vectorial routes in the transmission cycle of the hemoprotozoans in rodents. Our findings of H. canis in ticks other than R. sanguineus add to the observation that other ticks are also involved in the life cycle of Hepatozoon. Now that presence of Hepatozoon has been demonstrated in red foxes, gray wolves, mustelids and rodents from the Netherlands and/or Belgium, veterinary clinicians should be aware of the possibility of spill-over to domestic animals, such as dogs.

Unravelling the Diversity of Microorganisms in Ticks from Australian Wildlife

Ticks and tick-borne pathogens pose a significant threat to the health and welfare of humans and animals. Our knowledge about pathogens carried by ticks of Australian wildlife is limited. This study aimed to characterise ticks and tick-borne microorganisms from a range of wildlife species across six sites in Victoria, Australia. Following morphological and molecular characterisation (targeting 16S rRNA and cytochrome c oxidase I), tick DNA extracts (n = 140) were subjected to microfluidic real-time PCR-based screening for the detection of microorganisms and Rickettsia-specific real-time qPCRs. Five species of ixodid ticks were identified, including Aponomma auruginans, Ixodes (I.) antechini, I. kohlsi, I. tasmani and I. trichosuri. Phylogenetic analyses of 16S rRNA sequences of I. tasmani revealed two subclades, indicating a potential cryptic species. The microfluidic real-time PCR detected seven different microorganisms as a single (in 13/45 ticks) or multiple infections (27/45). The most common microorganisms detected were Apicomplexa (84.4%, 38/45) followed by Rickettsia sp. (55.6%, 25/45), Theileria sp. (22.2% 10/45), Bartonella sp. (17.8%, 8/45), Coxiella-like sp. (6.7%, 3/45), Hepatozoon sp. (2.2%, 1/45), and Ehrlichia sp. (2.2%, 1/45). Phylogenetic analyses of four Rickettsia loci showed that the Rickettsia isolates detected herein potentially belonged to a novel species of Rickettsia. This study demonstrated that ticks of Australian wildlife carry a diverse array of microorganisms. Given the direct and indirect human-wildlife-livestock interactions, there is a need to adopt a One Health approach for continuous surveillance of tick-associated pathogens/microorganisms to minimise the associated threats to animal and human health.

Ticks Infesting Dogs in Khyber Pakhtunkhwa, Pakistan: Detailed Epidemiological and Molecular Report

Ticks and tick-borne diseases are considered a major challenge for human and animal health in tropical, sub-tropical, and temperate regions of the world. However, only scarce information is available on the characterization of tick species infesting dogs in Pakistan. In this study, we present a comprehensive report on the epidemiological and phylogenetic aspects of ticks infesting dogs in Pakistan using the mitochondrial markers i.e. Cytochrome c oxidase subunit 1 (cox1) and 16S ribosomal RNA (16S rRNA) nucleotide sequences. A total of 300 dogs were examined and 1150 ixodid ticks were collected across central Khyber Pakhtunkhwa, Pakistan. The morpho-molecular characterization of hard ticks revealed the presence of two ixodid tick genera on dogs, i.e., Hyalomma and Rhipicephalus, including six tick species viz. Hyalomma dromedarii (15.9%), Hyalomma excavatum (3%), Rhipicephalus sanguineus s.l. (41.3%), Rhipicephalus turanicus s.s. (28.7%), Rhipicephalus haemaphysaloides (10.2%), and Rhipicephalus microplus (2%). The total prevalence of tick infestation in dogs was 61%. The district with the highest tick prevalence rate in dogs was Mardan (14.7%), followed by Peshawar (13%), Swabi (12%), Charsadda (11%), and Malakand (10.3%), respectively. Risk factors analysis indicated that some demographic and host management-associated factors such as host age, breed, exposure to acaricides treatment, and previous tick infestation history were associated with a higher risk of tick infestation on dogs. This is the first molecular report confirming the infestation of Hyalomma and Rhipicephalus tick species in the dog population from the study area. The present study also reported a new tick−host association between Hy. excavatum, Hy. dromedarii, and dogs. Phylogenetic analysis revealed that cox1 partial nucleotide sequences of Hy. excavatum in our dataset were 100% identical to similar tick specimens identified in Turkey, and those of Hy. dromedarii were identical to tick specimens from Iran. Whereas, Rh. haemaphysaloides and Rh. microplus’ cox1 partial nucleotide sequences were identical to sequences previously published from Pakistan. Rhipicephalus turanicus s.s. ‘s cox1 isolates from the present study were 99.8−100% identical to Pakistani-reported isolates, and those of Rh. sanguineus s.l. were 100% identical to Chinese specimens. Results on the genetic characterization of ticks were further confirmed by 16S rRNA partial nucleotide sequences analysis, which revealed 100% identity between the tick isolates of this study and those of Hy. excavatum reported from Turkey; Hy. dromedarii specimens reported from Senegal; Rh. haemaphysaloides, Rh. microplus, and Rh. turanicus s.s., previously published from Pakistan, and Rh. sanguineus s.l., published from China. Furthermore, phylogenetic analysis showed that the Rh. sanguineus s.l. isolates of this study clustered with specimens of the tropical lineage with 7.7−10% nucleotide divergence from the specimens of the temperate lineage. Further molecular works need to be performed throughout Pakistan to present a more detailed map of tick distribution with information about dog host associations, biological characteristics, and pathogen competence.

Enterocytozoon bieneusi in fecal samples from calves and cows in Austria

Enterocytozoon bieneusi is an obligate intracellular pathogen that infects livestock, companion animals, and wildlife and has the potential to cause severe diarrhea especially in immunocompromised humans. In the underlying study, fecal samples from 177 calves with diarrhea and 174 adult cows originating from 70 and 18 farms, respectively, in Austria were examined for the presence of E. bieneusi by polymerase chain reaction targeting the Internal Transcribed Spacer 1 (ITS1) region. All positive samples were further sequenced for genotype determination. Overall, sixteen of the 351 (4.6%) samples were positive for E. bieneusi, two of the 174 samples from cows (1.2%) and 14 of the 177 samples from calves (7.9%). In total, four genotypes, J (n = 2), I (n = 12), BEB4 (n = 3), and BEB8 (n = 1), were identified. The uncorrected p-distance between the four ITS1 lineages (344 bp) ranges from 0.3% to 2.9%. The lineages differ by 1 bp (I and J), 2 bp (J and BEB4), and 3 bp (I and BEB4), respectively, and BEB8 differs by 7 to 10 bp from the latter three lineages. Two of the E. bieneusi-positive calves showed an infection with two different genotypes. E. bieneusi occurred significantly more often in calves > 3 weeks (8/59) than in calves ≤ 3 weeks (6/118), respectively (p = 0.049). Calves with a known history of antimicrobial treatment (50 of 177 calves) shed E. bieneusi significantly more often than untreated calves (p = 0.012). There was no statistically significant difference in E. bieneusi shedding in calves with or without a medical history of antiparasitic treatment (p = 0.881). Calves showing a co-infection with Eimeria spp. shed E. bieneusi significantly more often than uninfected calves (p = 0.003). To our knowledge, this is the first report of E. bieneusi in cattle in Austria. Cattle should be considered as a reservoir for human infection since potentially zoonotic E. bieneusi genotypes were detected.

Deep tech innovation for parasite diagnosis: New dimensions and opportunities

By converging advanced science, engineering, and design, deep techs are bringing a great wave of future innovations by mastering challenges and problem complexity across sectors and the field of parasitology is no exception. Remarkable research and advancements can be seen in the field of parasite detection and diagnosis through smartphone applications. Supervised and unsupervised data deep learnings are heavily exploited for the development of automated neural network models for the prediction of parasites, eggs, etc., From microscopic smears and/or sample images with more than 99% accuracy. It is expected that several models will emerge in the future wherein greater attention is being paid to improving the model's accuracy. Invariably, it will increase the chances of adoption across the commercial sectors dealing in health and related applications. However, parasitic life cycle complexity, host range, morphological forms, etc., need to be considered further while developing such models to make the deep tech innovations perfect for bedside and field applications. In this review, the recent development of deep tech innovations focusing on human parasites has been discussed focusing on the present and future dimensions, opportunities, and applications.

Molecular Identification, Pathogenesis, and Life Cycle of Sarcocystis cruzi from Cattle (Bos taurus) in New Valley Governorate, Egypt

Sarcocystis cruzi was identified by molecular methods from an intermediate host, cattle (Bos taurus), in El-Kharga, New Valley Governorate, Egypt, and its life cycle and pathogenicity were studied in the final host, dogs (Canis familiaris). 600 slaughtered cattle aged 6-8 years (480/120 males/females) were included. In addition, three laboratory-bred, coccidian-free puppies aged 2-3 months were fed infected bovine muscles to locate the definitive host and analyze sporogony. 18S rRNA-specific gene primers were used for DNA amplification from esophageal muscles. These polymerase chain reaction (PCR) amplicons were subjected to restriction fragment length polymorphism (RFLP) and molecular sequence analysis. Infection was detected in 78.8% (473/600; 95% CI, 75.56-82.11%). Histopathological examination of esophageal muscles showed oval- to spherical-shaped cysts, 96.7 μm wide by 326.9 μm long; cysts in cardiac muscles were ovoid and smaller. Infected puppies began shedding sporocysts in feces 7 days post-inoculation and showed distorted organ architecture, severe cellular damage, and inflammatory lesions in liver, kidney, esophagus, and stomach. Three oocysts with different shapes and sizes were identified. Partial 18S rRNA gene sequences of isolated New Valley sarcocysts were identical to S. cruzi isolated from different areas, verifying their genetic relatedness. Our analysis suggests that S. cruzi is the most prevalent in slaughtered cattle in New Valley Governorate, Egypt.

Molecular detection of Toxoplasma gondii among commensal rodents from the Sahiwal division, Punjab, Pakistan

Toxoplasmosis is a zoonotic disease in humans and animals caused by the protozoan parasite Toxoplasma gondii. Rodents not only act as intermediate hosts for T. gondii but are also a significant source of T. gondii infection for other hosts. There is limited information about the prevalence of this protozoan within rodents in Pakistan. The current study was conducted to determine the prevalence of T. gondii in commensal rodents as well as associated risk factors. A total of 236 rats including Rattus rattus and Rattus norvegicus were captured from three districts of the Sahiwal division in Punjab province, Pakistan. Brain samples were collected from each specimen. Data was gathered about rodent species, gender, age, location, districts, seasonality, and habitat type. PCR assays were used to screen for T. gondii from the brain samples. A Chi-square analysis was used to investigate the association between positive samples and risk factors. A total of 236 rodent spleen samples were examined for detection of the B1 and SAG3 genes of T. gondii DNA by conventional PCR, and 14 (5.9%) were positive. T. gondii prevalence was higher in R. norvegicus (8.2%) compared to R. rattus (4.6%). All risk factors were statistically non-significant. This study provides evidence of T. gondii in rodents in the Sahiwal division and indicates that other animals and humans are at risk of infection.

Interpretable machine learning approach to analyze the effects of landscape and meteorological factors on mosquito occurrences in Seoul, South Korea

Mosquitoes are the underlying cause of various public health and economic problems. In this study, patterns of mosquito occurrence were analyzed based on landscape and meteorological factors in the metropolitan city of Seoul. We evaluated the influence of environmental factors on mosquito occurrence through the interpretation of prediction models with a machine learning algorithm. Through hierarchical cluster analysis, the study areas were classified into waterside and non-waterside areas, according to the landscape patterns. The mosquito occurrence was higher in the waterside area, and mosquito abundance was negatively affected by rainfall at the waterside. The mosquito occurrence was predicted in each cluster area based on the landscape and cumulative meteorological variables using a random forest algorithm. Both models exhibited good performance (both accuracy and AUROC > 0.8) in predicting the level of mosquito occurrence. The embedded relationship between the mosquito occurrence and the environmental factors in the models was explained using the Shapley additive explanation method. According to the variable importance and the partial dependence plots for each model, the waterside area was more influenced by the meteorological and land cover variables than the non-waterside area. Therefore, mosquito control strategies should consider the effects of landscape and meteorological conditions, including the temperature, rainfall, and the landscape heterogeneity. The present findings can contribute to the development of mosquito forecasting systems in metropolitan cities for the promotion of public health.

Occurrence of ticks and tick-borne mixed parasitic microbiota in cross-bred cattle in District Lahore, Pakistan

The present study was focused on the incidence of ticks and tick-borne diseases (TTBD) in cross-bred cattle (Friesian x Sahiwal) of two farms (n = 2548) in district Lahore, Pakistan. We collected total of 572 ticks (adults and nymphs) and blood samples (10 ml) for microscopic i.e., blood smear test - Giemsa Stain (BST) and molecular analysis; Reverse Line Blot-General Primer-PCR (RLB-PCR) and Specie Specific Primer PCR (SP-PCR) from infested cattle (n = 100) from months of April to September. Results: The tick specie identified was Rhipicephalus microplus at both farms, with significant difference in infestations rate amongst both farms (p< 0.0001). The cross-bred cattle having higher ratio of Friesian blood and lower ratio of Sahiwal blood were mostly infested by ticks (p < 0.0458) and haemoparasites (p <0.474) and vice versa. The SP-PCR showed higher number of haemoparasites infection than BST, which revealed 16% T. annulata (p < 0.0001 and k value 0.485, 0.0001), 51% B. bigemina (p < 0.0001 and k value 0.485, 0.0001) and 15% A. marginale (p < 0.001 and k value 0.207, 0.001), respectively. The single infection with B. bigemina was 34% (n = 34/100) and A. marginale 6% (n = 6/100). The double infection with T. annulata/B. bigemina was 8% (n = 8/100) and B. bigemina/A. marginale 1% (n = 1/100). Whereas the triple infection with T. annulata/B. bigemina/A .marginale was 8% (n = 8/100). The phylogenetic study of isolated sequence of T. annulata revealed close homology to isolates from Iran (87%), B. bigemina to isolates from Cuba (94 to 100%) and A. marginale with isolates from Pakistan (99 to 98%).

Multiple invasions, Wolbachia and human-aided transport drive the genetic variability of Aedes albopictus in the Iberian Peninsula

The Asian tiger mosquito, Aedes albopictus, is one of the most invasive species in the world. Native to the tropical forests of Southeast Asia, over the past 30 years it has rapidly spread throughout tropical and temperate regions of the world. Its dramatic expansion has resulted in public health concerns as a consequence of its vector competence for at least 16 viruses. Previous studies showed that Ae. albopictus spread has been facilitated by human-mediated transportation, but much remains unknown about how this has affected its genetic attributes. Here we examined the factors that contributed to shaping the current genetic constitution of Ae. albopictus in the Iberian Peninsula, where the species was first found in 2004, by combining population genetics and Bayesian modelling. We found that both mitochondrial and nuclear DNA markers showed a lack of genetic structure and the presence of worldwide dominant haplotypes, suggesting regular introductions from abroad. Mitochondrial DNA showed little genetic diversity compared to nuclear DNA, likely explained by infection with maternally transmitted bacteria of the genus Wolbachia. Multilevel models revealed that greater mosquito fluxes (estimated from commuting patterns and tiger mosquito population distribution) and spatial proximity between sampling sites were associated with lower nuclear genetic distance, suggesting that rapid short- and medium-distance dispersal is facilitated by humans through vehicular traffic. This study highlights the significant role of human transportation in shaping the genetic attributes of Ae. albopictus and promoting regional gene flow, and underscores the need for a territorially integrated surveillance across scales of this disease-carrying mosquito.

Molecular Epidemiological Investigation of Piroplasms and Anaplasmataceae Bacteria in Egyptian Domestic Animals and Associated Ticks

Piroplasmosis and anaplasmosis are serious tick-borne diseases (TBDs) that are concerning for the public and animal health. This study aimed to detect the molecular prevalence and epidemiological risk factors of Piroplasma and Anaplasma species in animal hosts and their associated ticks in Egypt. A total of 234 blood samples and 95 adult ticks were collected from animal hosts (112 cattle, 38 sheep, 28 goats, 26 buffaloes, 22 donkeys, and 8 horses) from six provinces of Egypt (AL-Faiyum, AL-Giza, Beni-Suef, Al-Minufia, Al-Beheira, and Matruh). Blood and tick samples were investigated by polymerase chain reaction coupled with sequencing targeting 18S and 16S RNA genes for Piroplasma and anaplasmataceae, respectively. Statistical analysis was conducted on the potential epidemiological factors. Of the 234 animals examined, 54 (23.08%) were positive for pathogens DNA distributed among the six provinces, where 10 (4.27%) were positive for Piroplasma, 44 (18.80%) for anaplasmataceae, and 5 (2.14%) were co-infected. Co-infections were observed only in cattle as Theileria annulata and Anaplasma marginale plus Babesia bigemina, A. marginale plus B. bigemina, and T. annulata plus B. bigemina. Piroplasmosis was recorded in cattle, with significant differences between their prevalence in their tick infestation factors. Animal species, age, and tick infestation were the potential risk factors for anaplasmosis. All ticks were free from piroplasms, but they revealed high prevalence rates of 72.63% (69/95) with anaplasmataceae. We identified T. annulata, B. bigemina, and A. marginale in cattle; A. platys in buffaloes; A. marginale and A. ovis in sheep; for the first time, A. ovis in goats; and Ehrlichia sp. in Rhipicephalus annulatus ticks. Our findings confirm the significant prevalence of piroplasmosis and anaplasmosis among subclinical and carrier animals in Egypt, highlighting the importance of the government developing policies to improve animal and public health security.

Lack of serological and molecular evidences of Zika virus circulation in non-human primates in three states from Brazil

BACKGROUND

Zika virus (ZIKV) was discovered in 1947 with the virus isolation from Rhesus monkey (Macaca mulatta) in Uganda forest, Africa. Old World Primates are involved in a sylvatic cycle of maintenance of this arbovirus, however a limited knowledge about the role of New World primates in ZIKV transmission cycles has been established.

OBJECTIVE

This work aimed to investigate the presence of enzootic circulation of ZIKV in New World Primates from three Brazilian states: São Paulo, Paraíba, and Paraná.

METHODS

We analyzed 100 non-human primate samples collected in 2018 and 2020 from free-ranging and captive environments from São Paulo (six municipalities belonging to Sorocaba region), Paraíba (João Pessoa municipality), and Paraná (Foz do Iguaçu municipality) using reverse transcriptase quantitative polymerase reaction (RT-qPCR) assays, indirect enzyme-linked immunosorbent assay (ELISA), and plaque reduction neutralization test (PRNT).

FINDINGS

All samples (n = 141) tested negative for the presence of ZIKV genome from tissue and blood samples. In addition, all sera (n = 58) from Foz do Iguaçu' non-human primates (NHPs) were negative in serological assays.

MAIN CONCLUSION

No evidence of ZIKV circulation (molecular and serological) was found in neotropical primates. In addition, the absence of antibodies against ZIKV suggests the absence of previous viral exposure of NHPs from Foz do Iguaçu-PR.

Unveiling of brain transcriptome of masked palm civet (Paguma larvata) with chronic infection of Toxoplasma gondii

BACKGROUND

The aim of this study was to gain an understanding of the transcriptomic changes that occur in a wild species when infected with Toxoplasma gondii. The masked palm civet, an artifically domesticated animal, was used as the model of a wild species. Transcriptome analysis was used to study alterations in gene expression in the domesticated masked palm civet after chronic infection with T. gondii.

METHODS

Masked palm civets were infected with 10⁵ T. gondii cysts and their brain tissue collected after 4 months of infection. RNA sequencing (RNA-Seq) was used to gain insight into the spectrum of genes that were differentially expressed due to infection. Quantitative reverse-transcription PCR (qRT-PCR) was also used to validate the level of expression of a set of differentially expressed genes (DEGs) obtained by sequencing.

RESULTS

DEGs were screened from the sequencing results and analyzed. A total of 2808 DEGs were detected, of which 860 were upregulated and 1948 were downregulated. RNA-Seq results were confirmed by qRT-PCR. DEGs were mainly enriched in cellular process and metabolic process based on gene ontology enrichment analysis. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that transcriptional changes in the brain of infected masked palm civets evolved over the course of infection and that DEGs were mainly enriched in the signal transduction, immune system processes, transport and catabolic pathways. Finally, 10 essential driving genes were identified from the immune signaling pathway.

CONCLUSIONS

This study revealed novel host genes which may provide target genes for the development of new therapeutics and detection methods for T. gondii infection in wild animals.

Emergence dynamics of adult Culicoides biting midges at two farms in south-east England

Background

Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of livestock arboviruses that cause diseases with significant economic, social and welfare impacts. Within temperate regions, livestock movement during arbovirus outbreaks can be facilitated by declaring a ‘seasonal vector-free period’ (SVFP) during winter when adult Culicoides are not active. In this study we carry out long-term monitoring of Culicoides adult emergence from larval development habitats at two farms in the UK to validate current definitions of the SVFP and to provide novel bionomic data for known vector species.

Methods

Standard emergence traps were used to collect emerging adult Culicoides from dung heaps at two cattle farms in the south-east of England from June to November 2016 and March 2017 to May 2018. Culicoides were morphologically identified to species or complex level and count data were analysed using a simple population dynamic model for pre-adult Culicoides that included meteorological components.

Results

More than 96,000 Culicoides were identified from 267 emergence trapping events across 2 years, revealing clear evidence of bivoltinism from peaks of male populations of Culicoidesobsoletus emerging from dung heaps. This pattern was also reflected in the emergence of adult female Obsoletus complex populations, which dominated the collections (64.4% of total catch) and emerged throughout the adult active period. Adult male C. obsoletus were observed emerging earlier than females (protandry) and emergence of both sexes occurred throughout the year. Culicoides chiopterus and Culicoides scoticus were also identified in spring emergence collections, providing the first evidence for the overwintering of larvae in dung heaps for these species.

Conclusions

This study demonstrates continual and highly variable rates of emergence of Culicoides throughout the year. A lack of evidence for mass emergence in spring along with the ability to observe male generations highlights the need for complementary surveillance techniques in addition to light-trap data when investigating seasonality and phenology. Evidence was found of other vector species, C. chiopterus and C. scoticus, utilising cattle dung heaps as an overwintering habitat, further highlighting the importance of these habitats on farms.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05370-z.

Molecular Survey and Genetic Characterization of Anaplasma marginale in Ticks Collected from Livestock Hosts in Pakistan

Simple Summary

Ticks transmit different disease-causing agents to humans and animals. Pakistan is an agricultural country, the rural economy mainly relies on livestock farming, and tick infestation is a severe constraint to its livelihood. The genus Anaplasma comprises obligate Gram-negative intracellular bacteria multiplying within the host cells and can be transmitted to humans and animals through the tick vector. The current study aimed to molecularly characterize the Anaplasma spp. in hard ticks infesting livestock in different districts of Khyber Pakhtunkhwa, Pakistan. The present study reported nine species of hard ticks infesting different hosts. The most prevalent tick life stage was adult females, followed by nymphs and adult males. In the phylogenetic tree, 16S rDNA sequences of Anaplasma spp. clustered with sequences of A. marginale. The hard ticks act as a carrier for the transmission of A. marginale. Further extensive country-wide research is required to explore the diverse tick species and the associated pathogens in Pakistan.

Abstract

Ticks transmit pathogens to animals and humans more often than any other arthropod vector. The rural economy of Pakistan mainly depends on livestock farming, and tick infestations cause severe problems in this sector. The present study aimed to molecularly characterize the Anaplasma spp. in hard ticks collected from six districts of Khyber Pakhtunkhwa, Pakistan. Ticks were collected from various livestock hosts, including cattle breeds (Holstein-Friesian, Jersey, Sahiwal, and Achai), Asian water buffaloes, sheep, and goats from March 2018 to February 2019. Collected ticks were morphologically identified and subjected to molecular screening of Anaplasma spp. by amplifying 16S rDNA sequences. Six hundred seventy-six ticks were collected from infested hosts (224/350, 64%). Among the nine morphologically identified tick species, the highest occurrence was noted for Rhipicephalus microplus (254, 37.6%), followed by Hyalomma anatolicum (136, 20.1%), Rhipicephalus haemaphysaloides (119, 17.6%), Rhipicephalus turanicus (116, 17.1%), Haemaphysalis montgomeryi (14, 2.1%), Hyalomma dromedarii (11, 1.6%), Haemaphysalis bispinosa (10, 1.5%), Hyalomma scupense (8, 1.2%), and Haemaphysalis kashmirensis (8, 1.2%). The occurrence of tick females was highest (260, 38.5%), followed by nymphs (246, 36.4%) and males (170, 25.1%). Overall, the highest occurrence of ticks was recorded in the Peshawar district (239, 35.3%), followed by Mardan (183, 27.1%), Charsadda (110, 16.3%), Swat (52, 7.7%), Shangla (48, 7.1%), and Chitral (44, 6.5%). Among these ticks, Anaplasma marginale was detected in R. microplus, R. turanicus, and R. haemaphysaloides. The 16S rDNA sequences showed high identity (98–100%) with A. marginale reported from Australia, China, Japan, Pakistan, Thailand, Uganda, and the USA. In phylogenetic analysis, the sequence of A. marginale clustered with the same species reported from Australia, China, Pakistan, Thailand, Uruguay, and the USA. Further molecular work regarding the diversity of tick species and associated pathogens is essential across the country.

Alterations in the jejunal microbiota and fecal metabolite profiles of rabbits infected with Eimeria intestinalis

Background

Rabbit coccidiosis is a major disease caused by various Eimeria species and causes enormous economic losses to the rabbit industry. Coccidia infection has a wide impact on the gut microbiota and intestinal biochemical equilibrium. In the present study, we established a model of Eimeria intestinalis infection in rabbits to evaluate the jejunal microbiota and fecal metabolite profiles.

Methods

Rabbits in the infected group were orally inoculated with 3 × 10³E. intestinalis oocysts. On the eighth day of infection, jejunal contents and feces were collected for 16S rRNA gene sequencing and liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis, respectively. Jejunum tissues were harvested for hematoxylin and eosin (H&E), periodic acid-Schiff (PAS), and immunohistochemistry (IHC) staining.

Results

Histopathological analysis showed that the whole jejunum was parasitized by E. intestinalis in a range of life cycle stages, and PAS staining showed that E. intestinalis infection caused extensive loss of goblet cells. IHC staining revealed that TNF-α expression was higher in the E. intestinalis infection group. Moreover, both the jejunal microbiota and metabolites significantly altered after E. intestinalis infection. At the genus level, the abundances of Escherichia and Enterococcus significantly increased in the infected group compared with the control group, while those of Oscillospira, Ruminococcus, Bacteroides, Akkermansia, Coprococcus, and Sarcina significantly decreased. In addition, 20 metabolites and two metabolic pathways were altered after E. intestinalis infection, and the major disrupted metabolic pathway was lipid metabolism.

Conclusions

Eimeria intestinalis infection induced intestinal inflammation and destroyed the intestinal homeostasis at the parasitized sites, leading to significant changes in the gut microbiota and subsequent corresponding changes in metabolites.

Graphical Abstract

Natural products from Photorhabdus and Xenorhabdus: mechanisms and impacts

Insects and fungal pathogens pose constant problems to public health and agriculture, especially in resource-limited parts of the world; and the use of chemical pesticides continues to be the main methods for the control of these organisms. Photorhabdus spp. and Xenorhabdus spp., (Fam; Morganellaceae), enteric symbionts of Steinernema, and Heterorhabditis nematodes are naturally found in soil on all continents, except Antarctic, and on many islands throughout the world. These bacteria produce diverse secondary metabolites that have important biological and ecological functions. Secondary metabolites include non-ribosomal peptides, polyketides, and/or hybrid natural products that are synthesized using polyketide synthetase (PRS), non-ribosomal peptide synthetase (NRPS), or similar enzymes and are sources of new pesticide/drug compounds and/or can serve as lead molecules for the design and synthesize of new alternatives that could replace current ones. This review addresses the effects of these bacterial symbionts on insect pests, fungal phytopathogens, and animal pathogens and discusses the substances, mechanisms, and impacts on agriculture and public health. KEY POINTS: • Insects and fungi are a constant menace to agricultural and public health. • Chemical-based control results in resistance development. • Photorhabdus and Xenorhabdus are compelling sources of biopesticides.

Genetic and morphological identification of filarial worm from Iberian hare in Portugal

The Iberian hare (Lepus granatensis) is an endemic species of the Iberian Peninsula and the only hare species found in Portugal, although also being present in some areas of Spain. The reduction of wild hare populations due to several ecological and sanitary factors, has been raising growing concerns in the recent years. Despite different helminth species were already described in Iberian hares in Portugal, to this date, no filarial worms have been identified in this species. Furthermore, only a few studies on lagomorphs' onchocercid worms are available, referring to other hosts species of hares and/or rabbits. In this study, we describe the presence of filarial worms in the blood vessels of two adult Iberian hares collected in 2019 in continental Portugal. Morphology and sequencing data from the 12S rRNA, coxI, 18S rRNA, myoHC, hsp70 and rbp1 genes, showed that the filaroid species were genetically related with Micipsella numidica. However, the extension of the genetic differences found with M. numidica suggests that the filaroids specimens under study belong to a new species, that we provisionally named Micipsella iberica n. sp.. The body location of this putative new parasite species and its physiological implications indicate that it may constitute a potential menace to the already fragile Iberian hare justifying, therefore, further investigation regarding the morphological characterization, prevalence and real clinical impact of this new parasite in hares.

First insights into the microbiome of Tunisian Hyalomma ticks gained through next-generation sequencing with a special focus on H. scupense

Ticks are one of the most important vectors of several pathogens affecting humans and animals. In addition to pathogens, ticks carry diverse microbiota of symbiotic and commensal microorganisms. In this study, we have investigated the first Tunisian insight into the microbial composition of the most dominant Hyalomma species infesting Tunisian cattle and explored the relative contribution of tick sex, life stage, and species to the diversity, richness and bacterial species of tick microbiome. In this regard, next generation sequencing for the 16S rRNA (V3-V4 region) of tick bacterial microbiota and metagenomic analysis were established. The analysis of the bacterial diversity reveals that H. marginatum and H. excavatum have greater diversity than H. scupense. Furthermore, microbial diversity and composition vary according to the tick’s life stage and sex in the specific case of H. scupense. The endosymbionts Francisella, Midichloria mitochondrii, and Rickettsia were shown to be the most prevalent in Hyalomma spp. Rickettsia, Francisella, Ehrlichia, and Erwinia are the most common zoonotic bacteria found in Hyalomma ticks. Accordingly, Hyalomma ticks could represent potential vectors for these zoonotic bacterial agents.

Multiple long-range host shifts of major Wolbachia supergroups infecting arthropods

Wolbachia is a genus of intracellular bacterial endosymbionts found in 20–66% of all insect species and a range of other invertebrates. It is classified as a single species, Wolbachia pipientis, divided into supergroups A to U, with supergroups A and B infecting arthropods exclusively. Wolbachia is transmitted mainly via vertical transmission through female oocytes, but can also be transmitted across different taxa by host shift (HS): the direct transmission of Wolbachia cells between organisms without involving vertically transmitted gametic cells. To assess the HS contribution, we recovered 50 orthologous genes from over 1000 Wolbachia genomes, reconstructed their phylogeny and calculated gene similarity. Of 15 supergroup A Wolbachia lineages, 10 have similarities ranging from 95 to 99.9%, while their hosts’ similarities are around 60 to 80%. For supergroup B, four out of eight lineages, which infect diverse and distantly-related organisms such as Acari, Hemiptera and Diptera, showed similarities from 93 to 97%. These results show that Wolbachia genomes have a much higher similarity when compared to their hosts’ genes, which is a major indicator of HS. Our comparative genomic analysis suggests that, at least for supergroups A and B, HS is more frequent than expected, occurring even between distantly-related species.

Meteorological and climatic variables predict the phenology of Ixodes ricinus nymph activity in France, accounting for habitat heterogeneity

Ixodes ricinus ticks (Acari: Ixodidae) are the most important vector for Lyme borreliosis in Europe. As climate change might affect their distributions and activities, this study aimed to determine the effects of environmental factors, i.e., meteorological, bioclimatic, and habitat characteristics on host-seeking (questing) activity of I. ricinus nymphs, an important stage in disease transmissions, across diverse climatic types in France over 8 years. Questing activity was observed using a repeated removal sampling with a cloth-dragging technique in 11 sampling sites from 7 tick observatories from 2014 to 2021 at approximately 1-month intervals, involving 631 sampling campaigns. Three phenological patterns were observed, potentially following a climatic gradient. The mixed-effects negative binomial regression revealed that observed nymph counts were driven by different interval-average meteorological variables, including 1-month moving average temperature, previous 3-to-6-month moving average temperature, and 6-month moving average minimum relative humidity. The interaction effects indicated that the phenology in colder climates peaked differently from that of warmer climates. Also, land cover characteristics that support the highest baseline abundance were moderate forest fragmentation with transition borders with agricultural areas. Finally, our model could potentially be used to predict seasonal human-tick exposure risks in France that could contribute to mitigating Lyme borreliosis risk.

Use of preventive measures and serological screening tools for Leishmania infantum infection in dogs from Europe

Background

There are several screening tools for detecting Leishmania infantum infection in dogs and various preventive measures to protect against it. Some studies have investigated them, but not many have described their current use. The aim of this study was to investigate which preventive measures and serological screening tools for L. infantum infection were employed from 2012 to 2018 in dogs from different endemic European countries.

Methods

A set of electronic datasheets was completed for each dog from several veterinary centres. Classification of preventive measures included: (1) repellents, (2) vaccines and (3) immunomodulators. Classification of serological tests included the: (1) direct agglutination test (DAT), (2) enzyme-linked immunosorbent assay (ELISA), (3) indirect immunofluorescence (IFI), (4) rapid tests and (5) other assays. Dogs were also classified depending on their risk of exposure and living area.

Results

Information from 3762 dogs was gathered. Preventive measures were applied in 91.5% of dogs and the most frequently used were repellents (86.2%) followed by vaccines (39.8%) and Leisguard^® (15.3%). The different types of repellents (collar and spot-on) were used similarly. A combination of a vaccine and repellents was preferred in the high-risk group while the low-risk preferred a combination of Leisguard^® and a repellent (Chi-square test: X² = 88.41, df = 10, P < 0.001). Furthermore, all preventive measures were similarly used through the years except for repellents, which were predicted to have a small increase of use each year. Regarding serological screening tools, the most used were rapid and ELISA tests. Rapid tests, ELISA tests and DAT were used similarly through the years, but a significant change was found in the use of IFI and other assays whose use decreased a little each year.

Conclusions

Repellents were the preferred measure, while vaccines and Leisguard^® were second-line options. Some dogs were not treated by any measures, which highlights the need for dog owner education. Moreover, there seems to be a preference for rapid tests in the clinical setting to detect specific L. infantum antibodies while ELISA or IFI are less often employed. This underlines an increasing problem, as qualitative rapid tests have a variable diagnostic performance limiting the adequate diagnosis of seropositive dogs in endemic areas.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05251-5.

Molecular survey of Babesia parasites in Kenya: first detailed report on occurrence of Babesia bovis in cattle

BACKGROUND

Among protozoan parasites in the genus Babesia, Babesia bigemina is endemic and widespread in the East African region while the status of the more pathogenic Babesia bovis remains unclear despite the presence of the tick vector, Rhipicephalus microplus, which transmits both species. Recent studies have confirmed the occurrence of R. microplus in coastal Kenya, and although B. bovis DNA has previously been detected in cattle blood in Kenya, no surveillance has been done to establish its prevalence. This study therefore investigated the occurrence of B. bovis in cattle in Kwale County, Kenya, where R. microplus is present in large numbers.

METHODS

A species-specific multiplex TaqMan real-time PCR assay targeting two Babesia bovis genes, 18S ribosomal RNA and mitochondrially-encoded cytochrome b and B. bigemina cytochrome b gene was used to screen 506 cattle blood DNA samples collected from Kwale County for presence of Babesia parasite DNA. A sub-set of 29 B. bovis real-time PCR-positive samples were further amplified using a B. bovis-specific spherical body protein-4 (SBP-4) nested PCR and the resulting products sequenced to confirm the presence of B. bovis.

RESULTS

A total of 131 animals (25.8%) were found to have bovine babesiosis based on real-time PCR. Twenty-four SBP4 nucleotide sequences obtained matched to B. bovis with a similarity of 97-100%. Of 131 infected animals, 87 (17.2%) were positive for B. bovis while 70 (13.8%) had B. bigemina and 26 (5.1%) were observed to be co-infected with both Babesia species. A total of 61 animals (12.1%) were found to be infected with B. bovis parasites only, while 44 animals (8.7%) had B. bigemina only. Babesia bovis and B. bigemina infections were detected in the three Kwale sub-counties.

CONCLUSION

These findings reveal high prevalence of pathogenic B. bovis in a Kenyan area cutting across a busy transboundary livestock trade route with neighbouring Tanzania. The Babesia multiplex real-time PCR assay used in this study is specific and can detect and differentiate the two Babesia species and should be used for routine B. bovis surveillance to monitor the spread and establishment of the pathogen in other African countries where B. bigemina is endemic. Moreover, these findings highlight the threat of fatal babesiosis caused by B. bovis, whose endemic status is yet to be established. GRAPHICAL ABTRACT.

A barcoding pipeline for mosquito surveillance in Nepal, a biodiverse dengue-endemic country

Background

Vector-borne diseases are on the rise on a global scale, which is anticipated to further accelerate because of anthropogenic climate change. Resource-limited regions are especially hard hit by this increment with the currently implemented surveillance programs being inadequate for the observed expansion of potential vector species. Cost-effective methods that can be easily implemented in resource-limited settings, e.g. under field conditions, are thus urgently needed to function as an early warning system for vector-borne disease epidemics. Our aim was to enhance entomological capacity in Nepal, a country with endemicity of numerous vector-borne diseases and with frequent outbreaks of dengue fever.

Methods

We used a field barcoding pipeline based on DNA nanopore sequencing (Oxford Nanopore Technologies) and verified its use for different mosquito life stages and storage methods. We furthermore hosted an online workshop to facilitate knowledge transfer to Nepalese scientific experts from different disciplines.

Results

The use of the barcoding pipeline could be verified for adult mosquitos and eggs, as well as for homogenized samples, dried specimens, samples that were stored in ethanol and frozen tissue. The transfer of knowledge was successful, as reflected by feedback from the participants and their wish to implement the method.

Conclusions

Cost effective strategies are urgently needed to assess the likelihood of disease outbreaks. We were able to show that field sequencing provides a solution that is cost-effective, undemanding in its implementation and easy to learn. The knowledge transfer to Nepalese scientific experts from different disciplines provides an opportunity for sustainable implementation of low-cost portable sequencing solutions in Nepal.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05255-1.

Protozoan and Rickettsial Pathogens in Ticks Collected from Infested Cattle from Turkey

Diseases caused by tick-transmitted pathogens including bacteria, viruses, and protozoa are of veterinary and medical importance, especially in tropical and subtropical regions including Turkey. Hence, molecular surveillance of tick-borne diseases will improve the understanding of their distribution towards effective control. This study aimed to investigate the presence and perform molecular characterization of Babesia sp., Theileria sp., Anaplasma sp., Ehrlichia sp., and Rickettsia sp. in tick species collected from cattle in five provinces of Turkey. A total of 277 adult ticks (males and females) were collected. After microscopic identification, tick pools were generated according to tick species, host animal, and sampling sites prior to DNA extraction. Molecular identification of the tick species was conducted through PCR assays. Out of 90 DNA pools, 57.8% (52/90) were detected to harbor at least 1 pathogen. The most frequently-detected pathogens were Babesia bovis, with a minimum detection rate of 7.9%, followed by Ehrlichia sp. (7.2%), Theileria annulata (5.8%), Coxiella sp. (3.3%), Anaplasma marginale (2.5%), Rickettsia sp. (2.5%), and B. occultans (0.7%). Rickettsia sp. identified in this study include Candidatus Rickettsia barbariae, R. aeschlimannii, and Rickettsia sp. Chad. All sequences obtained from this study showed 99.05−100% nucleotide identity with those deposited in GenBank (query cover range: 89−100%). This is the first molecular detection of Rickettsia sp. Chad, a variant of Astrakhan fever rickettsia, in Turkey. Results from this survey provide a reference for the distribution of ticks and tick-borne pathogens in cattle and expand the knowledge of tick-borne diseases in Turkey.

Association between densities of adult and immature stages of Aedes aegypti mosquitoes in space and time: implications for vector surveillance

BACKGROUND

Mosquito control is currently the main tool available to contain the spread of several arboviruses in Brazil. We have evaluated the association between entomological surveys of female adult Aedes aegypti and the Breteau index (BI) in space and time in a hyperendemic area, and compared the human resources costs required to measure each of these indicators.

METHODS

Entomological surveys were conducted between 2016 and 2019 in Vila Toninho, a neighborhood in the city of São José do Rio Preto, Brazil. Monthly records of collected mosquito specimens were made and then grouped by season.

RESULTS

Our findings showed that adult and immature mosquitoes are more related in time than in space, possibly due to differences in their habitats or in climate variables. Bayesian temporal modeling revealed that an increase in 1 standard deviation in the BI was associated with a 27% increase in the number of adult female mosquitoes when adjusted for climatic conditions. The cost of entomological surveys of adult mosquitoes was found to be 83% lower than the cost of determining the BI when covering the same geographic area.

CONCLUSIONS

For fine-scale assessments, a simple measure of adult Ae. aegypti abundance may be more realistic than aquatic indicators, but the adult indices are not necessarily the only reliable measure. Surveying adult female mosquitoes has significant potential for optimizing vector control strategies because, unlike the BI, this tool provides an effective indicator for micro-areas within an urban region. It should be noted that the results of the present study may be due to specific features of of the study area, and future studies should analyze whether the patterns found in the study neighborhood are also found in other regions.