In Vitro Activity of Allium cepa Organosulfur Derivatives against Canine Multidrug-Resistant Strains of Staphylococcus spp. and Enterobacteriaceae

BACKGROUND

The increase of multi-resistant bacteria, especially Staphylococcus spp. and Enterobacteriaceae, constitutes a challenge in veterinary medicine. The rapid growth of resistance is outpacing antibiotic discovery. Innovative strategies are needed, including the use of natural products like Allium species (Allium sativum L. and Allium cepa L.), which have been used empirically for centuries to treat infectious diseases in humans and farm and aquaculture animals due to their antibacterial properties.

METHODS

This study aimed to evaluate the in vitro activity of two Allium-derived compounds, propyl propane thiosulfinate (PTS) and propyl propane thiosulfonate (PTSO), against multi-resistant Staphylococcus spp. (n = 30) and Enterobacteriaceae (n = 26) isolated from dogs referred to a veterinary teaching hospital in Madrid.

RESULTS AND DISCUSSION

The results indicated the in vitro efficacy of PTSO/PTS against the tested bacterial strains, and 56.7% of Staphylococcus pseudintermedius and 53.8% of Enterobacteriaceae showed sensitivity to PTS and PTSO compared with classic antibiotics. In addition, 50% of S. pseudintermedius strains resistant to erythromycin, ibofloxacin, difloxacin and orbifloxacin and 50% of Enterobacteriaceae strains resistant to tetracycline and doxycycline were sensitive to PTS and PTSO. Although studies are needed to verify their efficacy in vivo, the combined use of PTS and PTSO exhibits promise in enhancing bacterial sensitivity against S. pseudintermedius and Enterobacteriaceae infections, providing a first insight into the potential of both compounds in veterinary practice.

Spatio-Temporal Cluster Detection of Dengue, Chikungunya, and Zika Viruses' Infection in Rio de Janeiro State from 2010 to 2019

Dengue (DENV), chikungunya (CHIKV), and Zika (ZIKV) virus infections are widespread throughout the Rio de Janeiro state. The co-circulation of these emergent arboviruses constitutes a serious public health problem, resulting in outbreaks that can spatially and temporally overlap. Environmental conditions favor the presence, maintenance, and expansion of Aedes aegypti, the primary vector of these urban arboviruses. This study assessed the detection of clusters of urban arboviruses in the Rio de Janeiro state from 2010 to 2019. Notified cases of dengue, chikungunya, and Zika were grouped by year according to the onset of symptoms and their municipality of residence. The study period recorded the highest number of dengue epidemics in the state along with the simultaneous circulation of chikungunya and Zika viruses. The analyzes showed that the central municipalities of the metropolitan regions were associated with higher risk areas. Central municipalities in metropolitan regions were the first most likely clusters for dengue and Zika, and the second most likely cluster for chikungunya. Furthermore, the northwest and north regions were comprised clusters with the highest relative risk for the three arboviruses, underscoring the impact of these arboviruses in less densely populated regions of Brazil. The identification of high-risk areas over time highlights the need for effective control measures, targeted prevention and control interventions for these urban arboviral diseases.

Epidemiology of the colonization and acquisition of methicillin-resistant staphylococci and vancomycin-resistant enterococci in dogs hospitalized in a clinic veterinary hospital in Spain

Antibiotic resistance is one of the biggest threats to human and animal health. Methicillin-resistant Staphylococcus spp. (MRS) and vancomycin-resistant Enterococcus spp. (VRE) are of increasing importance in hospital and/or nosocomial infections and represent a potential risk of transmission to humans from infected or colonized companion animals. Studies on the risk factors associated with colonization by multiresistant bacteria in animals are scarce. The present study aimed to estimate the prevalence and incidence of MRS and VRE in canine patients hospitalized in a veterinary hospital and to identify the risk factors for its acquisition and persistence. Nasal and perianal swabs were obtained from 72 dogs. Antimicrobial susceptibility assays and molecular detection of mecA and van genes were performed. A prevalence of 13.9% and incidence of 26.5% was observed in dogs colonized by MRS at hospital admission and release, respectively, higher values than those described in most veterinary studies. Thirty-five Staphylococcus isolates had mecA gene and showed higher resistance levels to most of the antimicrobials evaluated. Previous and concomitant use of antibiotics and corticosteroids has been associated with an increase in MRS colonization. The use of antibiotics in other animals living with the canine patients has also been identified as an associated factor, suggesting cross transmission. The presence of van-resistant genes from Enterococcus spp. was not detected. Pets should be considered possible vehicles of transmission and reservoirs for MRS bacteria and veterinary hospitals should be considered high-risk environments for the occurrence and spread of nosocomial infections and resistant bacteria.

A populational-based birth cohort study in a low-income urban area in Rio de Janeiro, Brazil: implementation and description of the characteristics of the study

A comprehensive cohort study including an entomological surveillance component can contribute to our knowledge of clinical aspects and transmission patterns of arbovirosis. This article describes the implementation of a populational-based birth cohort study that included an entomological surveillance component, and its associated challenges in a low-income community of Rio de Janeiro, Brazil. The participants were recruited in two periods: from 2012 to 2014, and from 2015 to 2017. The children had scheduled pediatric consultations and in case of fever. Epidemiological, clinical data and biological samples were collected at pediatric visits. Active febrile surveillance was performed by telephone calls, social networking, message apps, and household visits. A total of 387 newborns and 332 new children were included during the first and second recruitment periods, respectively. By July 2017, there were 451 children on follow-up. During the study, 2,759 pediatric visits were performed: 1,783 asymptomatic and 976 febrile/rash consultations. The number of febrile or rash consultations increased 3.5-fold after the use of media tools for surveillance. No temporal pattern, seasonality or peak of febrile cases was observed during the study period. A total of 10,105 adult mosquitoes (including 3,523 Aedes spp. and 6,582 Culex quinquefasciatus) and 46,047 Aedes eggs were collected from households, schools, and key sites. Although challenging, this structured sentinel populational-based birth cohort is relevant to the knowledge of risks and awareness of emerging pathogens.

Dispersion and oviposition of Aedes albopictus in a Brazilian slum: Initial evidence of Asian tiger mosquito domiciliation in urban environments

Aedes albopictus, originally considered as a secondary vector for arbovirus transmission, especially in areas where this species co-exist with Aedes aegypti, has been described in most regions of the world. Dispersion and domiciliation of Ae. albopictus in a complex of densely urbanized slums in Rio de Janeiro, Southeastern Brazil, was evidenced. In this study, we tested the hypotheses that 1) Ae. albopictus distribution in urban slums is negatively related to distance from vegetation, and 2) these vectors have taken on a domestic life style with a portion of the population feeding, ovipositing, and resting indoors. To do this, we developed an integrated surveillance proposal, aiming to detect the presence and abundance of Aedes mosquitoes. The study, based on a febrile syndrome surveillance system in a cohort of infants living in the slum complex, was performed on a weekly basis between February 2014 and April 2017. A total of 8,418 adult mosquitoes (3,052 Ae. aegypti, 44 Ae. albopictus, 16 Ae. scapularis, 4 Ae. fluviatilis and 5,302 Culex quinquefasciatus) were collected by direct aspiration and 46,047 Aedes spp. eggs were collected by oviposition traps. The Asian tiger mosquito, Ae. albopictus, was aspirated in its adult form (n = 44), and immature forms of this species (n = 12) were identified from the eggs collected by the ovitraps. In most collection sites, co-occurrence of Ae. aegypti and Ae. albopictus was observed. Key-sites, such as junkyards, thrift stores, factories, tire repair shops and garages, had the higher abundance of Ae. albopictus, followed by schools and households. We collected Ae. albopictus at up to 400 meters to the nearest vegetation cover. The log transformed (n+1) number of females Ae. albopictus captured at each collection point was inversely related to the distance to the nearest vegetation border. These results show that Ae. albopictus, a competent vector for important arboviruses and more commonly found in areas with higher vegetation coverage, is present and spread in neglected and densely urbanized areas, being collected at a long distance from the typical encounter areas for this species. Besides, as Ae. albopictus can easily move between sylvatic and urban environment, the entomological monitoring of Ae. albopictus should be an integral part of mosquito surveillance and control. Finally, key-sites, characterized by high human influx and presence of potential Aedes breeding sites, should be included in entomological monitoring.

Epidemiological study of hemotropic mycoplasmas (hemoplasmas) in cats from central Spain

Background

Hemotropic mycoplasmas (hemoplasmas) have been found infecting cats worldwide. However, studies about feline hemoplasma infections in Spain are scarce. Therefore, the purpose of the research was to evaluate the prevalence of feline hemotropic mycoplasmas and to characterize risk factors and clinical findings associated with these infections in a cat population from the Madrid area, Spain.

Methods

Polymerase chain reaction (PCR) was employed to detect Mycoplasma haemofelis (Mhf), “Candidatus Mycoplasma haemominutum” (CMhm) and “Candidatus Mycoplasma turicensis” (CMt) in blood samples from 456 client-owned and 138 stray cats from Madrid. In order to assess associations between these hemoplasma infections and epidemiological parameters, data regarding signalment, environment, prophylaxis measures, retrovirus status, clinical signs and laboratory findings were compiled, whenever possible.

Results

DNA of feline hemoplasmas was detected from the blood of 63 out of 594 cats (10.6%), with a prevalence of 3.7% (22/594) for Mhf, 8.1% (48/594) for CMhm and 0.5% (3/594) for CMt. Stray cats had statistically higher prevalences of feline hemoplasmas (15.9%) and, specifically, of Mhf (8.7%) than client-owned cats (9 and 2.2%, respectively). A total of seven cats (1.17%) were co-infected with “Candidatus M. haemominutum” and M. haemofelis, two (0.33%) with “Candidatus M. haemominutum” and “Candidatus M. turicensis” and another one (0.17%) with M. haemofelis and Candidatus “M. turicensis”. Male gender, collection of blood during warm months and FeLV/FIV positivity status were associated with hemotropic mycoplasma infection in cats from Madrid. Additionally, within the group of client-owned cats, hemoplasma infection was associated with adult age, outdoor access, and the existence of low haematocrit, erythrocyte count and haemoglobin concentration values.

Conclusions

To our knowledge, this is the first epidemiological survey of feline hemoplasmas performed in central Spain (Madrid). Our study confirms that “Ca. Mycoplasma haemominutum”, Mycoplasma haemofelis and “Ca. Mycoplasma turicensis” are infecting client-owned and stray cats in this region of Spain, “Ca. Mycoplasma haemominutum” being the most prevalent species. More studies are necessary to help understand the role of the natural infection by these species of hemoplasma in cats.

Early Evidence for Zika Virus Circulation among Aedes aegypti Mosquitoes, Rio de Janeiro, Brazil

During 2014-2016, we conducted mosquito-based Zika virus surveillance in Rio de Janeiro, Brazil. Results suggest that Zika virus was probably introduced into the area during May-November 2013 via multiple in-country sources. Furthermore, our results strengthen the hypothesis that Zika virus in the Americas originated in Brazil during October 2012-May 2013.

Molecular detection of Hepatozoon spp. and Cytauxzoon sp. in domestic and stray cats from Madrid, Spain

Background

Different species of apicomplexan protozoans of the genera Hepatozoon and Cytauxzoon can infect domestic cats, but their epidemiology and clinical relevance are not fully understood. The aim of this study was to assess the molecular prevalence of Hepatozoon spp. and Cytauxzoon spp. and to identify associated risk factors and clinical and laboratory abnormalities in a population of cats from Madrid, Spain.

Methods

Six hundred and forty-four client-owned and stray cats from Madrid, Spain, were included in this study. DNA samples were analyzed by two polymerase chain reaction (PCR) tests to detect a partial sequence of the 18S rRNA gene of Hepatozoon spp. and Cytauxzoon spp. In order to evaluate possible associations between infection by these protozoans and epidemiological or clinical parameters, data were collected related to: the season of sample collection, age, gender, spayed/neutered status, breed, living area, lifestyle, outdoor access, contact with other animals, prey on wild animals, history of tick or flea infestation, travel history, ectoparasiticide treatment, previous blood transfusion, previous tetracycline administration in the last 60 days, Feline Leukemia virus (FeLV) and Feline Immunodeficiency virus (FIV) status, positivity to other vector-borne diseases, the presence or absence of clinical signs and hematological or biochemical alterations.

Results

DNA of Hepatozoon spp. and Cytauxzoon sp. was amplified from the blood of 10 (1.6%) and 8 (1.2%) cats, respectively. Previous treatment with tetracyclines in the last 60 days, previous administration of blood transfusion, a decrease in haematocrit and an increase in creatinine were associated with Hepatozoon spp. infection. Cytauxzoon sp. infection was more frequent in samples collected during the winter months and in cats living in rural areas. This infection was associated with a FIV-positive status. Some of the cats that were positive for Hepatozoon spp. or Cytauxzoon sp. had been exposed to other vector-borne pathogens, such as Ehrlichia canis and Bartonella henselae.

Conclusions

Our results indicate that cats from Madrid, central Spain, are infected with Hepatozoon spp. and Cytauxzoon sp., although with a low prevalence. Further studies are needed to determine the virulence of these agents in Spanish cats.

Feeding behaviour of Culicoides spp. (Diptera: Ceratopogonidae) on cattle and sheep in northeast Germany

BACKGROUND

Culicoides spp. play an important role in the transmission of several vector-borne pathogens such as Bluetongue and Schmallenberg virus in Europe. To better understand the biology of local Culicoides species, a study divided into three parts was performed in northeast Germany to elucidate the feeding activity patterns (study A), preferential landing and feeding sites (study B) and host feeding preferences (study C) of Culicoides spp. using cattle and sheep as baits.

METHODS

In study A, the activity of Culicoides spp. was monitored over a 72 h period by collecting insects at regular intervals from the interior of drop traps with cattle or sheep standing inside. In study B, Culicoides spp. were directly aspirated from the coat and fleece of cattle and sheep during the peak activity period of Culicoides. In study C, Culicoides spp. were collected using drop traps with either cattle or sheep standing inside and located 10 m apart.

RESULTS

In study A, 3,545 Culicoides midges belonging to 13 species were collected, peak activity was observed at sunset. In study B, 2,024 Culicoides midges were collected. A significantly higher number of midges was collected from the belly and flank of cattle in comparison to their head region. In study C, 3,710 Culicoides midges were collected; 3,077 (83%) originated from cattle and 633 (17%) from sheep. Nearly half (46.7%) of the midges collected from cattle were engorged, significantly more than the number of engorged midges collected from sheep (7.5%). Culicoides from the Obsoletus complex (C. obsoletus and C. scoticus) were the most common Culicoides species encountered, followed by C. punctatus. Other species identified were C. dewulfi, C. chiopterus, C. pulicaris, C. lupicaris, C. pallidicornis, C. subfascipennis, C. achrayi, C. stigma, C. griseidorsum and C. subfagineus, the last two species are reported for the first time in Germany. Engorged C. chiopterus were collected in relatively high numbers from sheep, suggesting that this species may have a preference for sheep.

CONCLUSIONS

An insight into the feeding behaviour of local Culicoides species under field conditions in northeast Germany was obtained, with implications for the implementation of control measures and midge-borne disease risk analysis.

Vector-borne diseases in client-owned and stray cats from Madrid, Spain

The role of various vector-borne pathogens as a cause of disease in cats has not been clearly determined. The current study evaluated risk factors, clinical and laboratory abnormalities associated with Ehrlichia spp., Anaplasma spp., Neorickettsia spp., Leishmania spp., and Bartonella spp. infection or exposure in 680 client-owned and stray cats from Madrid, Spain. Our results indicate that a large portion (35.1%) of the cat population of Madrid, Spain, is exposed to at least one of the five vector-borne pathogens tested. We found seroreactivity to Bartonella henselae in 23.8%, to Ehrlichia canis in 9.9%, to Anaplasma phagocytophilum in 8.4%, to Leishmania infantum in 3.7%, and to Neorickettsia risticii in 1% of the feline study population. About 9.9% of cats had antibody reactivity to more than one agent. L. infantum DNA was amplified from four cats (0.6%), B. henselae DNA from one cat (0.15%), and B. clarridgeiae DNA from another cat (0.15%).