Tropical Diseases Research Articles

Bacterial microbiota from the gut of Rhodnius ecuadoriensis, a vector of Chagas disease in Ecuador's Central Coast and Southern Andes.

Chagas disease is a neglected tropical disease caused by the parasite Trypanosoma cruzi that is transmitted mainly by the feces of infected Triatomines. In Ecuador the main vector is Rhodnius ecuadoriensis which is distributed in several provinces of the country. More than 40% of these insects in the wild have T. cruzi as part of their intestinal microbiota. For this reason, the objective of this research was to characterize the intestinal bacterial microbiota of R. ecuadoriensis. The methodology used was based on the DNA extraction of the intestinal contents from the wild collected insects (adults and nymphs V), as well as the insects maintained at the insectary of the CISeAL. Finally, the samples were analyzed by metagenomics extensions based on the different selected criteria. The intestinal microbiota of R. ecuadoriensis presented a marked divergence between laboratory-raised and wild collected insects. This difference was observed in all stages and was similar between insects from Loja and Manabí. A large loss of microbial symbionts was observed in laboratory-raised insects. This study is a crucial first step in investigating microbiota interactions and advancing new methodologies.

Breaking the silence of female genital schistosomiasis in Ghana's health system: A case of health workers within the FAST project.

Female Genital Schistosomiasis (FGS) remains a critical and yet neglected topics in Neglected Tropical Diseases (NTDs), significantly affecting the health of women and girls worldwide. Health workers' knowledge of FGS is vital to the prevention and management of the disease. This study adopted an implementation research approach to identify and address the existing knowledge gap regarding FGS among healthcare workers in Ghana. This study was a 3-year (2020-2022) implementation research applying a pragmatic uncontrolled quasi-experimental study design. The study involved a baseline assessment, FGS training intervention for health workers and student nurses, distribution of FGS educational materials, and an endline assessment. A mixed-method approach was applied to data collection involving health workers from two schistosomiasis endemic districts and across the country. NVIVO 12 and STATA 14 were used for qualitative and quantitative data analysis, respectively. Prior to the intervention, the level of awareness about FGS among health workers was less than 8%, and most participants only understood FGS as merely urogenital schistosomiasis in females. In response to this gap, an FGS education intervention in the form of training of health workers, student nurses alongside the distribution of FGS educational materials were carried out. The intervention enhanced health workers' awareness of FGS to more than 61%, encompassing an enhanced understanding of the disease's signs and symptoms to more than 60%, as well as its management strategies. However, access to praziquantel, the primary treatment, remained a significant challenge. The FGS intervention effectively raised healthcare workers' awareness and knowledge. Expanding training and improving praziquantel access are essential for optimal FGS management. A multi-faceted approach involving individuals, communities, and the healthcare system is necessary for comprehensive FGS prevention and control.

Diagnostic Accuracy of Five Molecular Assays for the Detection of Dengue Virus.

Background and Objectives: The steady spread of dengue virus (DENV) poses a profound public health threat worldwide. Reverse transcription real-time polymerase chain reaction (RT2-PCR) has been increasingly recognized as a reference method for the diagnosis of acute dengue infection. The goal of this study was to assess the diagnostic accuracy of five different RT2-PCR kits for the detection of DENV in a historically processed set of sera samples. Materials and Methods: In this retrospective study, 25 sera samples from routinely processed unique adult patients with a known DENV status (previously tested in both molecular and serological assays) were tested in parallel using four conventional (RealStar Dengue PCR Kit 3.0, Clonit'ngo Zika, Dengue & Chikungunya, BioPerfectus Zika Virus/Dengue Virus/Chikungunya Virus Real Time PCR Kit and Novaplex Tropical fever virus) and one sample-to-result (STANDARD M10 Arbovirus Panel) RT2-PCR assays. Additionally, an end-point dilution analysis was conducted in quintuplicate on six serial dilutions of an RNA preparation obtained from a culture-grown DENV serotype 1 strain for a total of 150 tests. Results: The overall accuracy of the evaluated tests ranged from 84% to 100%. In particular, the sensitivity of three conventional RT2-PCR assays (RealStar, Clonit'ngo and Novaplex) was 100% (95% CI: 79.6-100%), while it was lower (73.3%; 95% CI: 48.1-89.1%) for the BioPerfectus kit. The sample-to-result STANDARD M10 panel performed comparatively well, showing a sensitivity of 92.9% (95% CI: 68.5-98.7%). No false positive results were registered in any assay. The end-point dilution analysis suggested that the RealStar kit had the lowest limit of detection. Conclusions: Available RT2-PCR kits for the detection of DENV are highly specific and generally sensitive and, therefore, their implementation in diagnostic pathways is advisable.

Unveiling the Unconventional: Exploring Atypical Manifestations of Scrub Typhus

Scrub typhus is a rickettsial illness caused by Orientia tsutsugamushi. It is a common cause of undifferentiated febrile illness, especially in the Indian subcontinent, usually with multiorgan involvement, though central nervous involvement is rare. Here, we demonstrate a case of a young female who presented with fever, headache, vomiting, and seizures. Her examination was remarkable for generalized blanchable macular rash, opsoclonus–myoclonus along with neck rigidity and mild epigastric tenderness. Contrast-enhanced magnetic resonance imaging brain was suggestive of leptomeningitis. She also had mild pancreatitis, transaminitis, thrombocytopenia, and transaminitis. Given the ongoing tropical fever burden in Northern India, further workup was done and enzyme-linked immunosorbent assay anti-scrub typhus immunoglobulin M came as positive. Doxycycline along with supportive treatment was started, and all signs and symptoms improved gradually.

Advances in Leishmania Vaccines: Current Development and Future Prospects.

Leishmaniasis is a neglected tropical disease caused by parasites of the genus Leishmania. As approved human vaccines are not available, treatment and prevention rely heavily on toxic chemotherapeutic agents, which face increasing resistance problems. The development of effective vaccines against human leishmaniasis is of utmost importance for the control of the disease. Strategies that have been considered for this purpose range from whole-killed and attenuated parasites to recombinant proteins and DNA vaccines. The ideal vaccine must be safe and effective, ensuring lasting immunity through a robust IL-12-driven Th1 adaptive immune response. Despite some success and years of effort, human vaccine trials have encountered difficulties in conferring durable protection against Leishmania, a problem that may be attributed to the parasite's antigenic diversity and the intricate nature of the host's immune response. The aim of this review is to provide a thorough overview of recent advances in Leishmania vaccine development, ranging from initial trials to recent achievements, such as the ChAd63-KH DNA vaccine, which underscores the potential for effective control of leishmaniasis through continued research in this field.

Communities’ knowledge, perceptions and preventive practices on soil-transmitted helminthes in Jimma, Oromia, Ethiopia: Formative mixed study

Background Soil-transmitted helminthes (STH) infections are one of the most common neglected tropical diseases. It has become one of a significant public health problem programmatically aimed for prevention and control in Ethiopia. Limited evidence is available on communities’ knowledge, perceptions, and practices regarding STH particularly in rural settings of Jimma, Ethiopia. Methods A community-based cross-sectional study triangulated with the qualitative method was conducted. The survey included 732 sampled rural households. Linear regression was used to assess association between predictors of knowledge and preventive practices of STH; likewise logistic regression was used to identify the predictors of hand washing practice at critical times. Kruskal-Wallis and Mann-Whitney tests were done to test differences in median risk perception score by socio-demographic factors. Qualitative data were collected through 7 key informant interviews, 6 focus group discussions and 7 expert group discussions then transcribed verbatim. Then, the data were coded, categorized and thematized using the Atlas ti.7.1.4 software package. Results Almost all of the respondents (99.6%) had heard of STH. The prevalence of comprehensive knowledge, risk perception and preventive practices towards STH were 46.7%:(95%CI:43.2, 50.4), 55.2%: (95%CI:51.2,59) and 44.4%:(95%CI:40.8, 48.2) respectively. Likewise, the magnitude of knowledge and practice of hand washing at critical times were 42.5%: (95%CI: 38.7,45.9) and 43.9%: (95%CI: 40, 47.5) respectively. Risk perception and comprehensive knowledge towards STH varied significantly across districts and by respondents’ educational status. Ownership of improved latrine was associated to comprehensive knowledge of STH. The STH preventive practice that varied across districts was predicted by the overall and knowledge specific to washing hands at critical times. The practice of washing hands at critical times was significantly associated to knowledge of hand washing, owning improved latrine, and age from 15 to 34 year compared to >45 year. Moreover, qualitative findings were supportive of the findings. Conclusion Despite reported exposures to STH communication opportunities, the study found modest levels of knowledge, perceptions, and preventive practices related to STH among rural communities where the burden of STH was the programmatic concern. These levels of knowledge, perceptions, and practices varied across the districts. Educational and latrine status predicted overall knowledge, whereas knowledge specific to hand washing and overall knowledge were predictors of STH preventive practice. Furthermore, washing hands during critical times was moderately improved among the young-aged, ownership of improved latrine and knowledgeable on hand washing. This study underscores the need for locally tailored and contextualized community behavioral change interventions needs to be strengthened toward improved STH preventive practices.

Designing of a chimeric multiepitope vaccine against bancroftian lymphatic filariasis through immunoinformatics approaches

The filarial worms of Wuchereria bancrofti are the primary cause of lymphatic filariasis (LF), a mosquito-borne disease among the neglected tropical parasitic diseases. Considering the global endemic consequences of the disease, there is a need to develop a successful vaccine candidate against LF. Using advanced immunoinformatics approaches, we designed two multiepitope vaccines targeting W. bancrofti’s glutathione S-transferase and thioredoxin. Therefore, we predicted several MHC-1, MHC-2, and B-cell epitopes from these proteins and mapped two vaccine candidates (V1 and V2). The vaccines were subsequently employed for physicochemical analysis, structural prediction and validation, docking and normal mode analysis, codon optimization, and immune simulation. The selected MHC-1, MHC-2, and B-cell epitopes were antigenic without allergenicity or toxicity. The designed vaccines were expected to be soluble, stable proteins under physiological conditions. Compared to V2, V1’s secondary and tertiary structures were simultaneously favorable, with Ramachandran plot analysis revealing 95.6% residues in favored areas. Subsequently, the molecular docking analysis indicated that the V1 had a high binding affinity for the TLR-2, TLR-4 and TLR-5, as suggested by the docking scores of -1248.7, -1038.5 and -1562.8, respectively. The NMA of these complexes further indicated their structural flexibility. Molecular dynamics simulations of V1-TLR complexes revealed V1-TLR-4 as the most stable, with the lowest free energy and minimal fluctuations, indicating the strongest binding affinity. The results of the codon optimization showed high levels of expression, with a favorable CAI score (<1.0). A three-dose vaccination analysis showed significant and persistent immunological responses, including adaptive and innate immune responses. The findings emphasize the potential of the V1 against W. bancrofti, but further validation is required through in vitro, in vivo, and clinical trials.

Prevalence of schistosomiasis among school children at Esuekyir community in the Central Region of Ghana

Schistosomiasis, an endemic neglected tropical disease in areas with poor sanitation, causes physical and mental defects in both children and adults. Various strategies, especially drug administration for morbidity control, have been implemented to combat the disease in Ghana and globally. Despite these efforts, schistosomiasis remains prevalent in Ghana, negatively impacting children's academic performance, growth, and overall quality of life. This study aimed to determine the prevalence of schistosomiasis in school children at Esuekyir, a peri-urban community in Ghana. A cross-sectional study using simple random sampling technique to select participants and collect stool and urine samples from 246 school children in Esuekyir was adopted. Microscopy of urine and stool samples was performed involving urine sedimentation and stool formol-ether sedimentation techniques to analyse for parasite eggs. Questionnaires were developed to help detect risk factors that expose these children to the disease. The prevalence of urogenital schistosomiasis in children at Esuekyir was 15.45% while that of intestinal schistosomiasis was 6.957.0%. There was one case of co-infection of urogenital and intestinal schistosomiasis from a 13 year old primary student. Children in primary school had higher risks of infection due to their activities around the water body. There was a significant association between class groups and urogenital schistosomiasis (p-value = 0.042). The presence of schistosomiasis in school children highlights the importance of targeted interventions and public health initiatives in addressing this specific disease condition especially in primary school children. Findings from the research revealed a higher prevalence of urogenital schistosomiasis in the study population as compared to intestinal schistosomiasis.

Congenital transmission of Chagas disease: The role of newborn therapy on the disease’s dynamics

Chagas disease, also known as American trypanosomiasis, is caused by a protozoan blood-borne pathogen called Trypanosoma cruzi. The World Health Organization (WHO) has classified Chagas as one of 21 neglected tropical diseases present in the world and estimates that 6-7 million people are currently infected with Chagas. Congenital transmission of Chagas disease contributes to a significant amount of new infections, especially in endemic areas where 22.5% of new infections are due to congenital transmission. In this paper, we investigate congenital transmission’s impact on Chagas disease dynamics through a mathematical model. Specifically, we examine how treating a proportion of infants born to infected individuals impacts the progression and spread of Chagas disease. The influence of newborn therapy on the dynamics of the model is thoroughly investigated, both theoretically and numerically. The results illustrate the importance of treating a high proportion of newborns to reduce the number of infected cases of the disease. The findings show that the therapy given to newborns is necessary but not sufficient to curb the transmission of Chagas disease, and a comprehensive approach that includes vector and vertical transmission control strategies is essential for eradicating Chagas disease. We also observed that if vector transmission can be controlled, then at least 55% of the newborns need to be treated to eliminate the disease.

Socio-economic risk factors for intestinal helminthiases in selected endemic communities in Mindanao, the Philippines: a cross-sectional study

Abstract Background Parasitic neglected tropical diseases (NTDs) or ‘infectious diseases of poverty’ continue to affect the poorest communities in the world, including in the Philippines. Socio-economic conditions contribute to persisting endemicity of these infectious diseases. As such, examining these underlying factors may help identify gaps in implementation of control programs. This study aimed to determine the prevalence of schistosomiasis and soil-transmitted helminthiasis (STH) and investigate the role of socio-economic and risk factors in the persistence of these diseases in endemic communities in the Philippines. Methods This cross-sectional study involving a total of 1,152 individuals from 386 randomly-selected households was conducted in eight municipalities in Mindanao, the Philippines. Participants were asked to submit fecal samples which were processed using the Kato-Katz technique to check for intestinal helminthiases. Moreover, each household head participated in a questionnaire survey investigating household conditions and knowledge, attitude, and practices related to intestinal helminthiases. Associations between questionnaire responses and intestinal helminth infection were assessed. Results Results demonstrated an overall schistosomiasis prevalence of 5.7% and soil-transmitted helminthiasis prevalence of 18.8% in the study population. Further, the household questionnaire revealed high awareness of intestinal helminthiases, but lower understanding of routes of transmission. Potentially risky behaviors such as walking outside barefoot and bathing in rivers were common. There was a strong association between municipality and prevalence of helminth infection. Educational attainment and higher “practice” scores (relating to practices which are effective in controlling intestinal helminths) were inversely associated with soil-transmitted helminth infection. Conclusion Results of the study showed remaining high endemicity of intestinal helminthiases in the area despite ongoing control programs. Poor socio-economic conditions and low awareness about how intestinal helminthiases are transmitted may be among the factors hindering success of intestinal helminth control programs in the provinces of Agusan del Sur and Surigao del Norte. Addressing these sustainability gaps could contribute to the success of alleviating the burden of intestinal helminthiases in endemic areas.

Evaluation of Chemokines MIG and IP-10 as Immunological Biomarkers of Human Visceral Leishmaniasis: A Systematic Review.

Visceral leishmaniasis (VL) is a neglected tropical disease that is potentially fatal when untreated. Current diagnostic methods have limitations that contribute to ongoing transmission and poor prognosis. Thus, new tests are needed to provide quick, accurate diagnoses and evaluate clinical progression and treatment efficacy. The monokine induced by interferon-gamma (MIG) and interferon-gamma-inducible protein 10 (IP-10) has been associated with the host susceptibility to VL with potential diagnostic and prognostic purposes. We performed a systematic review using four search databases (Scopus, PubMed, Web of Science, and MEDLINE) to identify studies assessing MIG and IP-10 as potential biomarkers in patients with VL across various clinical conditions. A total of 13 studies were potentially eligible and included in this review. The articles, in general, reveal that the chemokines MIG and IP-10 are elevated in response to infection by Leishmania spp., acting on the host's resistance to the development of the disease. They are associated with asymptomatic conditions and after VL treatment, and this relationship can be observed in both immunocompetent and immunocompromised individuals. Consequently, these chemokines hold relevance in the diagnoses and appropriate management of individuals with VL.

Extracts and Terpenoids from Stevia Species as Potential Anthelmintics for Neglected Tropical Diseases Caused by Cestode Parasites.

Cestodes are etiological agents of neglected diseases such as echinococcosis and cysticercosis, which are major public health problems. Antiparasitic treatment relies on a small number of approved drugs, which are often only partially effective, poorly tolerated and require prolonged administration. Thus, the discovery of novel potential treatments is critical. The Stevia genus (Asteraceae) includes species that are recognized as a source of bioactive compounds, with many species associated with medicinal uses. In this study, the cestocidal activity of four South American Stevia species that previously showed antiprotozoal activity was analyzed using a motility assay on the laboratory cestode model, Mesocestoides vogae. The four Stevia extracts showed cestocidal activity, with S. alpina var. alpina as the most active. The sesquiterpene lactones estafietin and eupatoriopicrin were purified from S. alpina var. alpina and S. maimarensis, respectively, and tested on M. vogae. Estafietin showed cestocidal activity, inhibiting parasite viability in a dose-dependent manner, even from the first day of incubation. Consistent with the motility effects, the extract of S. alpina var. alpina and estafietin induced marked alterations in the morphology of the parasite. The results of this report show that Stevia species represent a source of new molecules with potential for the treatment of neglected tropical diseases caused by cestodes.

An immigrant with easy fatigability and eosinophila caused by hookworm (A neglected tropical disease)

An immigrant with easy fatigability and eosinophila caused by hookworm (A neglected tropical disease)

Neutralizing Nanobodies against Venoms from Naja haje Species Captured in North Africa.

Snakebite envenoming (SBE) remains a severely neglected public health issue, particularly affecting tropical and subtropical regions, with Africa experiencing an estimated 435,000 to 580,000 snakebites annually, leading to high morbidity and mortality rates, especially across Africa and Asia. Recognized as a Neglected Tropical Disease, SBE management is further complicated by the inadequate efficacy of current antivenom treatments. Of particular concern are cobras (Naja sp.), whose neurotoxins can induce rapid fatal respiratory paralysis. In this study, we investigate the potential of nanobodies as a promising next-generation of immunotherapeutics against cobra venoms. Through a dual strategy of the characterization of venom toxic fractions from cobras captured for the first time in Algeria and Tunisia biotopes, coupled with in vitro assays to evaluate their interactions with acetylcholine receptors, and subsequent immunization of dromedaries to produce specific nanobodies, we identified two lethal fractions, F5 and F6, from each venom, and selected five nanobodies with significant binding and neutralizing of 3DL50 (0.74 mg/kg). The combination of these nanobodies demonstrated a synergistic effect, reaching 100% neutralizing efficacy of 2DL50 lethal venom fraction (0.88 mg/kg) doses in mice. Additionally, our findings highlighted the complex mechanism of cobra venom action through the lethal synergism among its major toxins.

In vitro efficacy of aquaculture antimicrobials and genetic determinants of resistance in bacterial isolates from tropical aquaculture disease outbreaks.

Understanding the efficacy of antimicrobials against pathogens from clinical samples is critical for their responsible use. The manuscript presents in vitro efficacy and antimicrobial resistance (AMR) genes in seven species of fish pathogens from the disease outbreaks of Indian aquaculture against oxytetracycline, florfenicol, oxolinic acid, and enrofloxacin. In vitro efficacy was evaluated by minimum inhibitory concentration and minimum bactericidal concentration. The gene-specific PCR screened AMR genes against quinolones (qnrA, qnrB, and qnrS) and tetracyclines (tetM, tetS, tetA, tetC, tetB, tetD, tetE, tetH, tetJ, tetG, and tetY). The results showed that Aeromonas veronii (45%) showed the maximum resistance phenotype, followed by Streptococcus agalactiae (40%), Photobacterium damselae (15%), Vibrio parahaemolyticus (10%), and Vibrio vulnificus (5%). There was no resistance among Vibrio harveyi and Vibrio alginolyticus against the tested antimicrobials. The positive association between tetA, tetB, tetC, tetM, or a combination of these genes to oxytetracycline resistance and qnrS to quinolone resistance indicated their potential in surveillance studies. The prevalence of resistance phenotypes (16.43%) and evaluated AMR genes (2.65%) against aquaculture antimicrobials was low. The resistance phenotype pattern abundance was 0.143. All the isolates showed susceptibility to florfenicol. The results help with the appropriate drug selection against each species in aquaculture practices.

Transforming Healthcare in Africa: The Role of Artificial Intelligence in Combatting Infectious Diseases, Neglected Tropical Diseases, and Antimicrobial Resistance

This review article focuses on the role of Artificial Intelligence (AI) in transforming healthcare in Africa, specifically in combatting infectious diseases, Neglected Tropical Diseases (NTDs), and antimicrobial resistance. We provide a comprehensive overview of the significance of AI in the healthcare industry, highlighting its urgency and importance in addressing these specific health challenges in Africa. We begin by discussing the role of AI in infectious disease surveillance and outbreak detection. We explore how AI technology can be employed for real-time tracking and prediction of outbreaks, providing examples of successful AI applications in infectious disease surveillance within the African context. Next, we examine the potential of AI-enabled diagnosis and treatment for faster and more accurate diagnoses of infectious diseases and NTDs. We highlight specific examples of AI applications in diagnosing and treating these diseases in Africa, showcasing the potential of AI to improve clinical outcomes and save lives. Furthermore, we focus on how AI-driven drug discovery and development can expedite the search for new treatments for infectious diseases and combat antimicrobial resistance. We present examples of AI applications in drug discovery within the African context, illustrating the potential for AI to revolutionize the development of effective therapeutics. In addition, we delve into how AI-powered public health interventions can enhance the design and implementation of targeted interventions. We explore how AI can optimize resource allocation and facilitate data-driven decision-making processes, providing examples of AI applications in public health in Africa. Finally, we address the challenges and limitations of implementing AI in combatting infectious diseases, NTDs, and antimicrobial resistance in Africa. We discuss potential barriers and ethical concerns surrounding AI applications in healthcare, aiming to encourage informed and responsible utilization of AI technologies. Overall, this review emphasizes the importance and potential of AI in combatting infectious diseases, NTDs, and antimicrobial resistance in Africa. It positions AI as a catalyst for revolutionizing healthcare in the region, leading to more effective disease surveillance, diagnosis, treatment, drug discovery, and public health interventions.

Implications of drug resistance in leprosy: disease course, reactions and the use of novel drugs.

Leprosy remains a significant neglected tropical disease despite the goal of elimination having been achieved in various endemic nations over the past two decades. Reactional episodes complicate the disease course, resulting in deformities and disability. The main aim of treatment is to kill Mycobacterium leprae and decrease the bacterial load, which could help prevent further bacilli transmission. A major concern in breaking the chain of transmission and possibly for recurrent reactions is the roleof drug-resistant bacilli. Though some data is available on the background prevalence of drug resistance in leprosy, there is a paucity of studies that look for resistance specifically in leprosy reactions. Administration of long-term steroids or immunosuppressants for chronic and recurrent responses in the presence of drug resistance has the twin effect of perpetuating the multiplication of resistant bacilli and encouraging the dissemination of leprosy. The increasing trend of prescribing second-line drugs for leprosy or type 2 reactions without prior assessment of drug resistance can potentially precipitate a severe public health problem as this can promote the development of resistance to second-line drugs as well. A comprehensive multicenter study, including drug resistance surveillance testing in cases of reactions, is necessary, along with the current measures to stop the spread of leprosy. Here, we have detailed the history of drug resistance in leprosy, given pointers on when to suspect drug resistance, described the role of resistance in reactions, methods of resistance testing, and the management of resistant cases with second-line therapy.

Evaluating Antibiotic Misuse and Cost Analysis Among Hospitalized Dengue Virus-Infected Adults: Insights From a Retrospective Cohort Study.

Dengue is a prevalent cause of acute febrile illness, predominantly in Asia, where it necessitates supportive care without the need for antibiotics. This study aimed to evaluate antibiotic usage and analyze hospitalization costs among adults infected with the dengue virus. This retrospective cohort study was conducted at the Hospital for Tropical Diseases, Thailand, in 2022. Two independent reviewers assessed all adult cases with confirmed dengue from 2016 to 2021. Determinants of inappropriateness were analyzed using Poisson regression. The study included 249 participants with over half presenting with severe dengue or dengue with warning signs upon admission. The cumulative incidence of antibiotic use was 9.3% (95% CI, 8.23-10.47), predominantly involving empirical treatment strategies. Ceftriaxone and doxycycline were the most frequently prescribed antibiotics. Notably, patients who received empirical antibiotics showed no definite or presumed bacterial infections. Among those who received definite strategies, inappropriate durations, including both short treatments and the overuse of broad-spectrum antibiotics, were observed. A private ward admission was identified as a significant predictor of inappropriate use, with an incidence rate ratio of 4.15 (95% CI, 1.16-14.82) compared with intensive care unit admission. Direct medical costs did not differ significantly between appropriate and inappropriate uses. The incidence of antibiotic use among dengue cases was moderate; however, inappropriate use by indication was observed. Antimicrobial stewardship strategies should be encouraged, particularly in patients with dengue with warning signs admitted to a general or private ward. Direct medical costs between appropriate and inappropriate use were comparable.

Methodological assessment for efficient collection of Schistosoma mansoni environmental DNA and improved schistosomiasis surveillance in tropical wetlands

Schistosomiasis, caused by trematodes of genus Schistosoma, is among the most seriously neglected tropical diseases. Although rapid surveillance of risk areas for Schistosoma transmission is vital to control schistosomiasis, the habitat and infection status of this parasite are difficult to assess. Environmental DNA (eDNA) analysis, involving the detection of extra-organismal DNA in water samples, facilitates cost-efficient and sensitive biomonitoring of aquatic environments and is a promising tool to identify Schistosoma habitat and infection risk areas. However, in tropical wetlands, highly turbid water causes filter clogging, thereby decreasing the filtration volume and increasing the risk of false negatives. Therefore, in this study, we aimed to conduct laboratory experiments and field surveys in Lake Victoria, Mbita, to determine the appropriate filter pore size for S. mansoni eDNA collection in terms of particle size and filtration volume. In the laboratory experiment, aquarium water was sequentially filtered using different pore size filters. Targeting >3 µm size fraction was found to be sufficient to capture S. mansoni eDNA particles, regardless of their life cycle stage (egg, miracidia, and cercaria). In the field surveys, GF/D (2.7 µm nominal pore size) filter yielded 2.5-times the filtration volume obtained with a smaller pore size filter and pre-filtration methods under the same time constraints. Moreover, a site-occupancy model was applied to the field detection results to estimate S. mansoni eDNA occurrence and detection probabilities and assess the number of water samples and PCR replicates necessary for efficient eDNA detection. Overall, this study reveals an effective method for S. mansoni eDNA detection in turbid water, facilitating the rapid and sensitive monitoring of its distribution and cost-effective identification of schistosomiasis transmission risk areas.

Etiologies and Associated Factors Death Among People Living with the Human Immunodeficiency Virus (PLHIV) Hospitalized for Febrile Consciousness Disorders in the Infectious and Tropical Diseases Departmentof the Donka National Hospital, Guinea

Introduction: Central nervous system (CNS) damage is common duringhuman immunodeficiency virus (HIV) infectionand occur in cases of immunosuppression, which leads to altered consciousness. The objective of this work was to identify the etiologies and factors associated with the death ofPLHIVhospitalized for febrile consciousness disorders in the infectious and tropical diseases departmentfrom Donka National Hospital. Methodology: This was a retrospective study of descriptive and analytical type over five (5) years in the infectious and tropical diseases department of the Donka National Hospital. Included in this study werePLHIV under treatment antiretroviraL(ART)or not, aged over 15, hospitalized in the infectious diseases department of Donka National Hospital. for febrile consciousness disorders or those who developed it during the study period. The parameters studied were sociodemographic characteristics, clinical picture, clinical staging of HIV/Acquired Immuno-Deficiency Syndrome(AIDS) according tothe World Health Organization(WHO). Factors associated with deaths were searched from logistic regression in multivariate analysis and all variables with a value of P˂0.05 were considered statistically significant. Results: Two hundred and five out of five hundred and thirty-four (205/534) files ofPLHIV, hospitalized for febrile consciousness disorderswere sampled and enrolled for this studyi.e. a prevalence of 38.39%. The average age of the patients was 42.28 ± 12.54 years with a sex ratio of 0.97. Cerebral toxoplasmosis was the most common etiology.Severe immunosuppression was one of the factors statistically associated with death. Conclusion: Febrile consciousness disorders remain very common, with multiple etiologies inPLHIV. The CD4 count ≤ 200 cells/mm3, the depth of the coma and the absence of antiretroviral treatment were the factors associated with death.