Febrile illness diagnostics and the malaria-industrial complex: a socio-environmental perspective

COVID-19 in patients presenting with malaria-like symptoms at a primary healthcare facility in Accra, Ghana

BACKGROUND

Malaria is a common and severe public health problem in Ghana and largely responsible for febrile symptoms presented at health facilities in the country. Other infectious diseases, including COVID-19, may mimic malaria due to their shared non-specific symptoms such as fever and headache thus leading to misdiagnosis. This study therefore investigated COVID-19 among patients presenting with malaria-like symptoms at Korle-Bu Polyclinic, Accra, Ghana.

METHODS

This study enrolled 300 patients presenting with malaria-like symptoms aged ≥18yrs. After consent was obtained from study patients, two to three millilitres of whole blood, nasopharyngeal and oropharyngeal swab samples, were collected for screening of Plasmodium falciparum using malaria rapid diagnostic test, microscopy and nested PCR, and SARS-CoV-2 using SARS-CoV-2 antigen test and Real-time PCR, respectively. The plasma and whole blood were also used for COVID-19 antibody testing and full blood counts using hematological analyser. SARS-CoV-2 whole genome sequencing was performed using MinIon sequencing.

RESULTS

The prevalence of malaria by microscopy, RDT and nested PCR were 2.3%, 2.3% and 2.7% respectively. The detection of SARS-CoV-2 by COVID-19 Rapid Antigen Test and Real-time PCR were 8.7% and 20% respectively. The Delta variant was reported in 23 of 25 SARS-CoV-2 positives with CT values below 30. Headache was the most common symptom presented by study participants (95%). Comorbidities reported were hypertension, asthma and diabetes. One hundred and thirteen (37.8%) of the study participants had prior exposure to SARS CoV-2 and (34/51) 66.7% of Astrazeneca vaccinated patients had no IgG antibody.

CONCLUSION

It may be difficult to use clinical characteristics to distinguish between patients with COVID-19 having malaria-like symptoms. Detection of IgM using RDTs may be useful in predicting CT values for SARS-CoV-2 real-time PCR and therefore transmission.

Increasing prevalence of malaria and acute dengue virus coinfection in Africa: a meta-analysis and meta-regression of cross-sectional studies

BACKGROUND

Malaria and dengue fever are the leading causes of acute, undifferentiated febrile illness. In Africa, misdiagnosis of dengue fever as malaria is a common scenario. Through a systematic review of the published literature, this study seeks to estimate the prevalence of dengue and malaria coinfection among acute undifferentiated febrile diseases in Africa.

METHODS

Relevant publications were systematically searched in the PubMed, Cochrane Library, and Google Scholar until May 19, 2023. A random-effects meta-analysis and meta-regression were used to summarize and examine the prevalence estimates.

RESULTS

Twenty-two studies with 22,803 acute undifferentiated febrile patients from 10 countries in Africa were included. The meta-analysis findings revealed a pooled prevalence of malaria and dengue coinfection of 4.2%, with Central Africa having the highest rate (4.7%), followed by East Africa (2.7%) and West Africa (1.6%). Continent-wide, Plasmodium falciparum and acute dengue virus coinfection prevalence increased significantly from 0.9% during 2008-2013 to 3.8% during 2014-2017 and to 5.5% during 2018-2021 (p = 0.0414).

CONCLUSION

There was a high and increasing prevalence of malaria and acute dengue virus coinfection in Africa. Healthcare workers should bear in mind the possibility of dengue infection as a differential diagnosis for acute febrile illness, as well as the possibility of coexisting malaria and dengue in endemic areas. In addition, high-quality multicentre studies are required to verify the above conclusions. Protocol registration number: CRD42022311301.

Metagenomic surveillance uncovers diverse and novel viral taxa in febrile patients from Nigeria

Effective infectious disease surveillance in high-risk regions is critical for clinical care and pandemic preemption; however, few clinical diagnostics are available for the wide range of potential human pathogens. Here, we conduct unbiased metagenomic sequencing of 593 samples from febrile Nigerian patients collected in three settings: i) population-level surveillance of individuals presenting with symptoms consistent with Lassa Fever (LF); ii) real-time investigations of outbreaks with suspected infectious etiologies; and iii) undiagnosed clinically challenging cases. We identify 13 distinct viruses, including the second and third documented cases of human blood-associated dicistrovirus, and a highly divergent, unclassified dicistrovirus that we name human blood-associated dicistrovirus 2. We show that pegivirus C is a common co-infection in individuals with LF and is associated with lower Lassa viral loads and favorable outcomes. We help uncover the causes of three outbreaks as yellow fever virus, monkeypox virus, and a noninfectious cause, the latter ultimately determined to be pesticide poisoning. We demonstrate that a local, Nigerian-driven metagenomics response to complex public health scenarios generates accurate, real-time differential diagnoses, yielding insights that inform policy.

Malaria and typhoid fever among patients presenting with febrile illnesses in Ga West Municipality, Ghana

BACKGROUND

Clinicians in areas where malaria and typhoid fever are co-endemic often treat infected patients irrationally, which may lead to the emergence of drug resistance and extra cost to patients. This study determined the proportion of febrile conditions attributable to either malaria and/or typhoid fever and the susceptibility patterns of Salmonella spp. isolates to commonly used antimicrobial agents in Ghana.

METHODS

One hundred and fifty-seven (157) febrile patients attending the Ga West Municipal Hospital, Ghana, from February to May 2017 were sampled. Blood samples were collected for cultivation of pathogenic bacteria and the susceptibility of the Salmonella isolates to antimicrobial agents was performed using the Kirby-Bauer disk diffusion method with antibiotic discs on Müller Hinton agar plates. For each sample, conventional Widal test for the detection of Salmonella spp was done as well as blood film preparation for detection of Plasmodium spp. Data on the socio-demographic and clinical characteristics of the study participants were collected using an android technology software kobo-collect by interview.

RESULTS

Of the total number of patients aged 2-37 years (median age = 6 years, IQR 3-11), 82 (52.2%) were females. The proportion of febrile patients with falciparum malaria was 57/157 (36.3%), while Salmonella typhi O and H antigens were detected in 23/157 (14.6%) of the samples. The detection rate of Salmonella spp in febrile patients was 10/157 (6.4%). Malaria and typhoid fever coinfection using Widal test and blood culture was 9 (5.7%) and 3 (1.9%), respectively. The isolates were highly susceptible to cefotaxime, ceftriaxone, ciprofloxacin, and amikacin but resistant to ampicillin, tetracycline, co-trimoxazole, gentamicin, cefuroxime, chloramphenicol, and meropenem.

CONCLUSION

Plasmodium falciparum and Salmonella spp coinfections were only up to 1.9%, while malaria and typhoid fever, individually, were responsible for 36.3% and 6.4%, respectively. Treatment of febrile conditions must be based on laboratory findings in order not to expose patients to unnecessary side effects of antibiotics and reduce the emergence and spread of drug resistance against antibiotics.

Adherence to 14-day radical cure for Plasmodium vivax malaria in Papua, Indonesia: a mixed-methods study

BACKGROUND

Reducing the risk of recurrent Plasmodium vivax malaria is critical for malaria control and elimination. Primaquine (PQ) is the only widely available drug against P. vivax dormant liver stages, but is recommended as a 14-day regimen, which can undermine adherence to a complete course of treatment.

METHODS

This is a mixed-methods study to assess socio-cultural factors influencing adherence to a 14-day PQ regimen in a 3-arm, treatment effectiveness trial in Papua, Indonesia. The qualitative strand, consisting of interviews and participant observation was triangulated with a quantitative strand in which trial participants were surveyed using a questionnaire.

RESULTS

Trial participants differentiated between two types of malaria: tersiana and tropika, equivalent to P. vivax and Plasmodium falciparum infection, respectively. The perceived severity of both types was similar with 44.0% (267/607) perceiving tersiana vs. 45.1% (274/607) perceiving tropika as more severe. There was no perceived differentiation whether malaria episodes were due to a new infection or relapse; and 71.3% (433/607) acknowledged the possibility of recurrence. Participants were familiar with malaria symptoms and delaying health facility visit by 1-2 days was perceived to increase the likelihood of a positive test. Prior to health facility visits, symptoms were treated with leftover drugs kept at home (40.4%; 245/607) or bought over the counter (17.0%; 103/607). Malaria was considered to be cured with 'blue drugs' (referring to dihydroartemisinin-piperaquine). Conversely, 'brown drugs,' referring to PQ, were not considered malaria medication and instead were perceived as supplements. Adherence to malaria treatment was 71.2% (131/184), in the supervised arm, 56.9% (91/160) in the unsupervised arm and 62.4% (164/263) in the control arm; p = 0.019. Adherence was 47.5% (47/99) among highland Papuans, 51.7% (76/147) among lowland Papuans, and 72.9% (263/361) among non-Papuans; p < 0.001.

CONCLUSION

Adherence to malaria treatment was a socio-culturally embedded process during which patients (re-)evaluated the characteristics of the medicines in relation to the course of the illness, their past experiences with illness, and the perceived benefits of the treatment. Structural barriers that hinder the process of patient adherence are crucial to consider in the development and rollout of effective malaria treatment policies.

Spatiotemporal overlapping of dengue, chikungunya, and malaria infections in children in Kenya

Malaria, chikungunya virus (CHIKV), and dengue virus (DENV) are endemic causes of fever among children in Kenya. The risks of infection are multifactorial and may be influenced by built and social environments. The high resolution overlapping of these diseases and factors affecting their spatial heterogeneity has not been investigated in Kenya. From 2014-2018, we prospectively followed a cohort of children from four communities in both coastal and western Kenya. Overall, 9.8% were CHIKV seropositive, 5.5% were DENV seropositive, and 39.1% were malaria positive (3521 children tested). The spatial analysis identified hot-spots for all three diseases in each site and in multiple years. The results of the model showed that the risk of exposure was linked to demographics with common factors for the three diseases including the presence of litter, crowded households, and higher wealth in these communities. These insights are of high importance to improve surveillance and targeted control of mosquito-borne diseases in Kenya.

Arbovirus Epidemiology: The Mystery of Unnoticed Epidemics in Ghana, West Africa

It is evident that all the countries surrounding Ghana have experienced epidemics of key arboviruses of medical importance, such as the recent dengue fever epidemic in Burkina Faso. Therefore, Ghana is considered a ripe zone for epidemics of arboviruses, mainly dengue. Surprisingly, Ghana never experienced the propounded deadly dengue epidemic. Indeed, it is mysterious because the mosquito vectors capable of transmitting the dengue virus, such as Aedes aegypti, were identified in Ghana through entomological investigations. Additionally, cases may be missed, as the diagnostic and surveillance capacities of the country are weak. Therefore, we review the arbovirus situation and outline probable reasons for the epidemic mystery in the country. Most of the recorded cases of arbovirus infections were usually investigated via serology by detecting IgM and IgG immunoglobulins in clinical samples, which is indicative of prior exposure but not an active case. This led to the identification of yellow fever virus and dengue virus as the main circulating arboviruses among the Ghanaian population. However, major yellow fever epidemics were reported for over a decade. It is important to note that the reviewed arboviruses were not frequently detected in the vectors. The data highlight the necessity of strengthening the diagnostics and the need for continuous arbovirus and vector surveillance to provide an early warning system for future arbovirus epidemics.

Antimicrobial Stewardship in Tropical Infectious Diseases: Focusing on Dengue and Malaria

Acute undifferentiated febrile illness (AUFI) is the presenting symptom of various tropical and infectious diseases. Viral infection is generally the most common cause of AUFI, accounting for 8–11.8% of cases; thus, antibiotics might be unnecessary. Dengue and malaria are common tropical infectious diseases requiring effective supportive treatment and antimalarial agents, respectively. The uncertainty of early diagnosis results in widespread empirical antimicrobial treatment in high -income as well as in low-and middle-income countries. Although rapid diagnostic tests (RDTs) have been shown to limit antibiotic prescriptions in dengue and malaria, we observed a wide range of antibiotic prescriptions for 13–92.7% of cases in previous literature, particularly in RDT-negative malaria cases. Given several RDT limitations, antimicrobial stewardship (AMS) appears to be an effective strategy for controlling unnecessary antibiotic use and antimicrobial resistance (AMR) prevention. This program should be endorsed by a multidisciplinary team in tropical diseases to control collateral damage of inappropriate antimicrobial use. Empirical antibiotic treatment should be administered based on clinical judgement, microbiological evidence, and local epidemiological data. Rapid termination of antibiotic therapy, including disease control or elimination, is the mainstay of AMS in tropical diseases. Local and international sectors should implement an AMS programme to reduce AMR in the Tropics.

When Local Trade-Offs between SDGs Turn Out to Be Wealth-Dependent: Interaction between Expanding Rice Cultivation and Eradicating Malaria in Rwanda

Interactions between SDGs are increasingly mapped and mediating factors that determine whether existing synergies or trade-offs can be identified. However, if and how the wealth status of the concerned population shapes whether SDG interaction constitutes a vicious or virtuous circle is largely overlooked. This article focuses on interaction between SDG2 (nutrition) and SDG3 (health), in particular, the relationship between rice production intensification and the fight against malaria, and thus the role of wealth in explaining the trade-off. This study employed a large-scale survey of rural households (n = 3968) in eastern Rwanda, conducted at a time when a rapid expansion of rice fields co-existed with a strong resurgence of malaria. Logistic regression shows that rice-cultivating households faced significant higher malaria risk, as proxied by fever incidence, confirming the negative externality of agricultural intensification on public health through offering a habitat for vector-borne diseases. Even though rice-cultivating households tend to be higher up the local wealth distribution than those outside the rice sector, its distributional effects are generally biased against the poor. Poorer households outside the rice sector hardly share in the benefits from increased rice production but suffer the consequences in terms of increased malaria risk. The case thus draws attention to the importance of using a distributional lens when analyzing interaction between SDGs locally.

Uncovering the Burden of Dengue in Africa: Considerations on Magnitude, Misdiagnosis, and Ancestry

Dengue is a re-emerging neglected disease of major public health importance. This review highlights important considerations for dengue disease in Africa, including epidemiology and underestimation of disease burden in African countries, issues with malaria misdiagnosis and co-infections, and potential evidence of genetic protection from severe dengue disease in populations of African descent. The findings indicate that dengue virus prevalence in African countries and populations may be more widespread than reported data suggests, and that the Aedes mosquito vectors appear to be increasing in dissemination and number. Changes in climate, population, and plastic pollution are expected to worsen the dengue situation in Africa. Dengue misdiagnosis is also a problem in Africa, especially due to the typical non-specific clinical presentation of dengue leading to misdiagnosis as malaria. Finally, research suggests that a protective genetic component against severe dengue exists in African descent populations, but further studies should be conducted to strengthen this association in various populations, taking into consideration socioeconomic factors that may contribute to these findings. The main takeaway is that Africa should not be overlooked when it comes to dengue, and more attention and resources should be devoted to this disease in Africa.

Clinical presentations, diagnostics, treatments and treatment costs of children and adults with febrile illness in a tertiary referral hospital in south-eastern Guinea: A retrospective longitudinal cohort study

Background

Febrile illness is frequent among patients in the tropics. It is caused by a wide variety of common diseases such as malaria or gastrointestinal infections but also by less common but highly contagious pathogens with epidemic potential. This study describes the clinical features of adult and paediatric patients with febrile illness in in the largest tertiary referral hospital in south-eastern Guinea, a region at high risk for viral haemorrhagic fever outbreaks. The study further compares their diagnostic characteristics, treatments and outcomes with non-febrile patients in order to contribute to the local epidemiology of febrile illness.

Methods

We used retrospective data collection to record demographic and clinical data of all incoming patients during a study period of three months. For the follow-up study of inpatients, we retrospectively reviewed patient charts for diagnostic characteristics, diagnoses and outcomes.

Results

Of the 4317 incoming patients during the study period, 9.5% had a febrile illness. The most used diagnostic measures to identify causative agents in febrile patients were point-of-care tests and most treatments relied on antibiotics. Most common discharge diagnoses for febrile inpatients were malaria (9.6% adults, 56.7% children), salmonella gastroenteritis/typhoid (10.6% adults, 7.8% children) and respiratory infection/pneumonia (5.3% adults, 18.7% children). Inpatient mortality for children was significantly higher in febrile than non-febrile children (18.5% vs. 5.1%, p<0.001) and considerably higher in febrile than non-febrile adults (29.8% vs. 25.0%, p = 0.404).

Conclusions

Malaria, respiratory infection and gastroenteritis are considered the main causes for febrile illness. The wide reliance on rapid diagnostic tests to diagnose febrile patients not only risks to over- or under-diagnose certain diseases but also leaves the possibility of highly infectious diseases in febrile patients unexplored. Furthermore, the heavy reliance on antibiotics risks to cause antimicrobial resistance. High mortality rates in febrile patients, especially children, should be of concern to public health authorities.

Trends in fever case management for febrile inpatients in a low malaria incidence setting of Tanzania

OBJECTIVES

In 2010, WHO published guidelines emphasising parasitological confirmation of malaria before treatment. We present data on changes in fever case management in a low malaria transmission setting of northern Tanzania after 2010.

METHODS

We compared diagnoses, treatments and outcomes from two hospital-based prospective cohort studies, Cohort 1 (2011-2014) and Cohort 2 (2016-2019), that enrolled febrile children and adults. All participants underwent quality-assured malaria blood smear-microscopy. Participants who were malaria smear-microscopy negative but received a diagnosis of malaria or received an antimalarial were categorised as malaria over-diagnosis and over-treatment, respectively.

RESULTS

We analysed data from 2098 participants. The median (IQR) age was 27 (3-43) years and 1047 (50.0%) were female. Malaria was detected in 23 (2.3%) participants in Cohort 1 and 42 (3.8%) in Cohort 2 (p = 0.059). Malaria over-diagnosis occurred in 334 (35.0%) participants in Cohort 1 and 190 (17.7%) in Cohort 2 (p < 0.001). Malaria over-treatment occurred in 528 (55.1%) participants in Cohort 1 and 196 (18.3%) in Cohort 2 (p < 0.001). There were 30 (3.1%) deaths in Cohort 1 and 60 (5.4%) in Cohort 2 (p = 0.007). All deaths occurred among smear-negative participants.

CONCLUSION

We observed a substantial decline in malaria over-diagnosis and over-treatment among febrile inpatients in northern Tanzania between two time periods after 2010. Despite changes, some smear-negative participants were still diagnosed and treated for malaria. Our results highlight the need for continued monitoring of fever case management across different malaria epidemiological settings in sub-Saharan Africa.

Screening for tick-borne and tick-associated viruses in ticks collected in Ghana

Ticks are blood-sucking arthropods that transmit many pathogens, including arboviruses. Arboviruses transmitted by ticks are generally referred to as tick-borne viruses (TBVs). TBVs are known to cause diseases in humans, pets, and livestock. There is, however, very limited information on the occurrence and distribution of TBVs in sub-Saharan Africa. This study was designed to determine the presence and distribution of ticks infesting dogs and cattle in Ghana, as well as to identify the tick-borne or tick-associated viruses they harbour. A more diverse population of ticks was found to infest cattle (three genera) relative to those infesting dogs (one genus). Six phleboviruses and an orthonairovirus were detected in tick pools screened by RT-PCR. Subsequent sequence analysis revealed two distinct phleboviruses and the previously reported Odaw virus in ticks collected from dogs and a virus (16GH-T27) most closely related to four unclassified phleboviruses in ticks collected from cattle. The virus 16GH-T27 was considered a strain of Balambala tick virus (BTV) and named BTV strain 16GH-T27. Next-generation sequencing analysis of the BTV-positive tick pool detected only the L and S segments. Phylogenetic analysis revealed that BTV clustered with viruses previously defined as M-segment-deficient phleboviruses. The orthonairovirus detected in ticks collected from cattle was confirmed to be the medically important Dugbe virus. Furthermore, we discuss the importance of understanding the presence and distribution of ticks and TBVs in disease prevention and mitigation and the implications for public health. Our findings contribute to the knowledge pool on TBVs and tick-associated viruses.

Challenge of diagnosing acute infections in poor resource settings in Africa

Frequent disease outbreaks and acute infections occur in rural and low-income urban areas of Africa, with many health systems unprepared to diagnose and control diseases that are recurrent, endemic or have extended their geographic zone. In this review, we focus on acute infections that can be characterized by sudden onset, rapid progression, severe symptoms and poor prognosis. Consequently, these infections require early diagnosis and intervention. While effective vaccines have been developed against some of these diseases, lack of compliance and accessibility, and the need for repeated or multiple vaccinations mean large populations can remain vulnerable to infection. It follows that there is a need for enhancement of national surveillance and diagnostic capacity to avert morbidity and mortality from acute infections. We discuss the limitations of traditional diagnostic methods and explore the relative merits and applicability of protein-, carbohydrate- and nucleic acid-based rapid diagnostic tests that have been trialled for some infectious diseases. We also discuss the utility and limitations of antibody-based serological diagnostics and explore how systems biology approaches can better inform diagnosis. Lastly, given the complexity and high cost associated with after-service support of emerging technologies, we propose that, for resource-limited settings in Africa, multiplex point-of-care diagnostic tools be tailor-made to detect both recurrent acute infections and endemic infections.

Mosquito-Associated Viruses and Their Related Mosquitoes in West Africa

Mosquito-associated viruses (MAVs), including mosquito-specific viruses (MSVs) and mosquito-borne (arbo)viruses (MBVs), are an increasing public, veterinary, and global health concern, and West Africa is projected to be the next front for arboviral diseases. As in-depth knowledge of the ecologies of both western African MAVs and related mosquitoes is still limited, we review available and comprehensive data on their diversity, abundance, and distribution. Data on MAVs’ occurrence and related mosquitoes were extracted from peer-reviewed publications. Data on MSVs, and mosquito and vertebrate host ranges are sparse. However, more data are available on MBVs (i.e., dengue, yellow fever, chikungunya, Zika, and Rift Valley fever viruses), detected in wild and domestic animals, and humans, with infections more concentrated in urban areas and areas affected by strong anthropogenic changes. Aedes aegypti, Culex quinquefasciatus, and Aedes albopictus are incriminated as key arbovirus vectors. These findings outline MAV, related mosquitoes, key knowledge gaps, and future research areas. Additionally, these data highlight the need to increase our understanding of MAVs and their impact on host mosquito ecology, to improve our knowledge of arbovirus transmission, and to develop specific strategies and capacities for arboviral disease surveillance, diagnostic, prevention, control, and outbreak responses in West Africa.

Comparative performance study of three Ebola rapid diagnostic tests in Guinea

Background

The 2014/15 Ebola outbreak in West Africa resulted in 11,000 deaths and massive strain on local health systems, and the ongoing outbreak in Democratic Republic of Congo has afflicted more than 3000 people. Accurate, rapid Ebola diagnostics suitable for field deployment would enable prompt identification and effective response to future outbreaks, yet remain largely unavailable. The purpose of this study was to assess the accuracy of three novel rapid diagnostic tests (RDTs): an Ebola, an Ebola-Malaria, and a Fever Panel test that includes Ebola, all from a single manufacturer.

Methods

We evaluated the three RDTs in 109 Ebola-positive and 96 Ebola-negative stored serum samples collected during the outbreak in Guinea in 2014/15, and tested by real-time polymerase chain reaction (RT-PCR). Sensitivity, specificity, and overall percent agreement were calculated for each RDT using RT-PCR as a reference standard, stratified by Ct value ranges.

Results

All tests performed with high accuracy on samples with low Ct value (high viral load). The Fever Panel test performed with the highest accuracy, with a sensitivity of 89.9% and specificity of 90.6%. The Ebola and Ebola-Malaria tests performed comparably to each other: sensitivity was 77.1 and 78% respectively, and specificity was 91.7% for the Ebola test and 95.8% for the Ebola-Malaria test.

Conclusions

This study evaluated the accuracy of three novel rapid diagnostic tests for Ebola. The tests may have significant public health relevance, particularly the Fever Panel test, which detects seven pathogens including Ebola. Given limitations to the study resulting from uncertain sample quality, further evaluation is warranted. All tests performed with highest accuracy on samples with low Ct value (high viral load), and the data presented here suggests that these RDTs may be useful for point-of-care diagnosis of cases in the context of an outbreak. Restrictions to their use in non-severe Ebola cases or for longitudinal monitoring, when viral loads are lower, may be appropriate. Highlighting the challenge in developing and evaluating Ebola RDTs, there were concerns regarding sample integrity and reference testing, and there is a need for additional research to validate these assays.

Effect of a free healthcare policy on health services utilisation for non-malarial febrile illness by children under five years in Burkina Faso: an interrupted time series analysis

OBJECTIVE

To assess the effect of a free healthcare policy for children under five years old implemented in Burkina Faso since April 2016, on the use of health care of non-malarial febrile illnesses (NMFI).

METHODS

To assess the immediate and long-term effect of the free healthcare policy in place, we conducted an interrupted time series analysis of routinely collected data on febrile illnesses from three urban primary health centres of Ouagadougou between 1 January 2015 and 31 December 2016.

RESULTS

Of the 39 046 febrile cases reported in the study period, 17 017 NMFI were included in the study. Compared to the period before the intervention, we observed an immediate, non-statistically significant increase of 7% in the number of NMFI (IRR = 1.07; 95% CI = 0.75, 1.51). Compared to the trend that would have been expected in absence of the intervention, the results showed a small but sustained increase of 6% in the trend of monthly number of NMFI during the intervention period (IRR = 1.06; 95%CI = 1.01, 1.12).

CONCLUSION

Our study highlighted an increase in the uptake of healthcare services, specifically for NMFI by children under five years of age, after the implementation of a free care policy. This analysis contributes to informing decision makers on the need to strengthen the capacities of healthcare centres and to anticipate the challenges of the sustainability of this policy.

Water insecurity and urban poverty in the Global South: Implications for health and human biology

OBJECTIVES

Over half of the world's population (4 billion people) experience severe water scarcity at least one month per year, while half a billion people experience severe water scarcity throughout the year. Despite progress from national and global interventions, a staggering proportion of the Global South remains water insecure. Rapid urban growth and associated demographic changes, climate change, and governance failure have also fostered the growth and expansion of urban informal settlements and slums where widespread poverty and environmental hazards exacerbate the impact of water insecurity on health. This article reflects on the interactions between water insecurity and urban poverty in the Global South across four categories of health outcomes: gastrointestinal diseases, mosquito-borne diseases, injuries, and mental illness. These examples highlight the mechanisms through which urban poverty exacerbates the adverse health effects of water insecurity.

METHODS

The four selected health outcomes were chosen a priori to represent two communicable conditions with well-developed literatures, and two noncommunicable conditions with newer literatures that have emerged over the last decade. We conducted a narrative literature review of scholarly and gray literature appearing between January 2000 and April 2019 using several online scholarly databases.

RESULTS

Gastrointestinal diseases, mosquito-borne diseases, injuries, and mental illness all exemplified the relationship between water insecurity and urban poverty through human biological pathways. For each of the four health categories, we identified frontiers for human biology research contributions to the water-poverty-health nexus.

CONCLUSIONS

We discuss our findings in the context of three crosscutting themes that merit innovative research approaches: stressor interactions and trade-offs, exposure thresholds, and intervention efficacy. We reiterate that the global burden of disease associated with water insecurity cannot be addressed in isolation from efforts to alleviate extreme poverty.

Phylogeography and invasion history of Aedes aegypti, the Dengue and Zika mosquito vector in Cape Verde islands (West Africa)

Aedes-borne arboviruses have spread globally with outbreaks of vast impact on human populations and health systems. The West African archipelago of Cape Verde had its first outbreak of Dengue in 2009, at the time the largest recorded in Africa, and was one of the few African countries affected by the Zika virus epidemic. Aedes aegypti was the mosquito vector involved in both outbreaks. We performed a phylogeographic and population genetics study of A. aegypti in Cape Verde in order to infer the geographic origin and evolutionary history of this mosquito. These results are discussed with respect to the implications for vector control and prevention of future outbreaks. Mosquitoes captured before and after the Dengue outbreak on the islands of Santiago, Brava, and Fogo were analyzed with two mitochondrial genes COI and ND4, 14 microsatellite loci and five kdr mutations. Genetic variability was comparable to other African populations. Our results suggest that A. aegypti invaded Cape Verde at the beginning of the Holocene from West Africa. Given the historic importance of Cape Verde in the transatlantic trade of the 16th-17th centuries, a possible contribution to the genetic pool of the founding populations in the New World cannot be fully discarded. However, contemporary gene flow with the Americas is likely to be infrequent. No kdr mutations associated with pyrethroid resistance were detected. The implications for vector control and prevention of future outbreaks are discussed.

Quantifying the incidence of severe-febrile-illness hospital admissions in sub-Saharan Africa

Severe-febrile-illness (SFI) is a common cause of morbidity and mortality across sub-Saharan Africa (SSA). The burden of SFI in SSA is currently unknown and its estimation is fraught with challenges. This is due to a lack of diagnostic capacity for SFI in SSA, and thus a dearth of baseline data on the underlying etiology of SFI cases and scant SFI-specific causative-agent prevalence data. To highlight the public health significance of SFI in SSA, we developed a Bayesian model to quantify the incidence of SFI hospital admissions in SSA. Our estimates indicate a mean population-weighted SFI-inpatient-admission incidence rate of 18.4 (6.8–31.1, 68% CrI) per 1000 people for the year 2014, across all ages within areas of SSA with stable Plasmodium falciparum transmission. We further estimated a total of 16,200,337 (5,993,249–27,321,779, 68% CrI) SFI hospital admissions. This analysis reveals the significant burden of SFI in hospitals in SSA, but also highlights the paucity of pathogen-specific prevalence and incidence data for SFI in SSA. Future improvements in pathogen-specific diagnostics for causative agents of SFI will increase the abundance of SFI-specific prevalence and incidence data, aid future estimations of SFI burden, and enable clinicians to identify SFI-specific pathogens, administer appropriate treatment and management, and facilitate appropriate antibiotic use.

Detection of Dengue viruses among febrile patients in Lagos, Nigeria and phylogenetics of circulating Dengue serotypes in Africa

Dengue fever, a mosquito borne viral disease, is caused by Dengue virus. This virus and its vector is endemic in most tropical countries including Nigeria. Dengue presents with febrile symptoms and is a major cause of morbidity and mortality in affected countries. The infection presently has no licensed drugs and vaccine is only available for previously exposed individuals. Despite the endemicity of Dengue in Nigeria, very few studies have identified circulating Dengue genotypes in the country. There is also sparse information on the occurrence, distribution and temporal patterns of circulating dengue virus serotypes as well as genotypes in Africa. This situation creates barriers to effective control of the infection in the continent. This study identified Dengue serotypes and genotypes among febrile patients in two health centers in Lagos, Nigeria. Phylogenetic analysis of Dengue sequences previously collected from African countries and submitted to GenBank database from 1944 till date was also performed. One hundred and thirty febrile persons were recruited for the study between April and August 2018. Eleven (8.5%) persons were Dengue virus positive. Dengue virus serotypes 1 (genotype I) and 3 (genotype I) were identified as actively circulating in Lagos, Nigeria. DENV 1 genotype V, DENV 2 cosmopolitan genotype and DENV 3 genotype III has over the years been the predominant circulating Dengue strains in Africa. Relative genotypic stability of circulating Dengue serotypes in Africa occurred over the past five decades. This may be due to limited investigations on circulating Dengue serotypes among asymptomatic individuals in the region as most studies focused on disease outbreaks and imported cases. There is the need to describe circulating Dengue genotypes in northern Africa, southern Africa as well as among asymptomatic individuals in other parts of Africa as this will provide further information on the diversity of Dengue genotypes circulating in the region.

Detection of Dengue Virus among Children with Suspected Malaria, Accra, Ghana

We report new molecular evidence of locally acquired dengue virus infections in Ghana. We detected dengue viral RNA among children with suspected malaria by using a multipathogen real-time PCR. Subsequent sequence analysis revealed a close relationship with dengue virus serotype 2, which was implicated in a 2016 outbreak in Burkina Faso.

Plasmodium falciparum malaria cases detected for prompt treatment by rapid diagnostic tests in the Ho Teaching Hospital of the Volta Region of Ghana

Background

Prompt diagnosis and effective treatment of malaria cases with efficacious drugs is an important strategy in the management and control of malaria in endemic populations. As part of a study investigating the factors modulating the development of Plasmodium falciparum gametocytes in the human host, we assessed the rate of RDT positivity of patients in different departments of the Ho Teaching Hospital and the relation with age and anaemia.

Materials and methods

Eight-hundred and ten individuals attending clinic at various departments within the Ho Teaching Hospital were screened for malaria antigenaemia using RDT as a point-of-entry investigation. RDT positive individuals were immediately treated for malaria whereas RDT negative individuals were treated for other ailments. Haematological analyses were performed for 69 of these patients and the relationship between RDT results and haemoglobin levels were investigated.

Results

The overall RDT positivity rate was 19.8% (160/810) of all individuals screened. There was no significant difference in the haemoglobin levels of RDT-positive and RDT-negative individuals (p value = 0.272). The highest number of attendees screened was children in the paediatric outpatient department and paediatric ward, 62% (507/810), with RDT positivity rate of 17% (91/507). We found the highest RDT positivity rate of 51% (19/37) in the male medical ward.

Conclusions

This study shows that RDT is a useful tool in promoting prompt diagnosis and management of malaria and though children form a majority of hospital attendees and malaria infections, the frequency of malaria detection may be higher in adults as compared to children.

Low cost, low tech SNP genotyping tools for resource-limited areas: Plague in Madagascar as a model

BACKGROUND

Genetic analysis of pathogenic organisms is a useful tool for linking human cases together and/or to potential environmental sources. The resulting data can also provide information on evolutionary patterns within a targeted species and phenotypic traits. However, the instruments often used to generate genotyping data, such as single nucleotide polymorphisms (SNPs), can be expensive and sometimes require advanced technologies to implement. This places many genotyping tools out of reach for laboratories that do not specialize in genetic studies and/or lack the requisite financial and technological resources. To address this issue, we developed a low cost and low tech genotyping system, termed agarose-MAMA, which combines traditional PCR and agarose gel electrophoresis to target phylogenetically informative SNPs.

METHODOLOGY/PRINCIPAL FINDINGS

To demonstrate the utility of this approach for generating genotype data in a resource-constrained area (Madagascar), we designed an agarose-MAMA system targeting previously characterized SNPs within Yersinia pestis, the causative agent of plague. We then used this system to genetically type pathogenic strains of Y. pestis in a Malagasy laboratory not specialized in genetic studies, the Institut Pasteur de Madagascar (IPM). We conducted rigorous assay performance validations to assess potential variation introduced by differing research facilities, reagents, and personnel and found no difference in SNP genotyping results. These agarose-MAMA PCR assays are currently employed as an investigative tool at IPM, providing Malagasy researchers a means to improve the value of their plague epidemiological investigations by linking outbreaks to potential sources through genetic characterization of isolates and to improve understanding of disease ecology that may contribute to a long-term control effort.

CONCLUSIONS

The success of our study demonstrates that the SNP-based genotyping capacity of laboratories in developing countries can be expanded with manageable financial cost for resource constraint laboratories. This is a practical formula that reduces resource-driven limitations to genetic research and promises to advance global collective knowledge of infectious diseases emanating from resource limited regions of the world.