Tropical Medicine and Infectious Disease

17 pages, 3418 KiB

Open AccessArticle

Malaria Mortality in Brazil: Age–Period–Cohort Effects, Sociodemographic Factors, and Sustainable Development Indicators

by Mariusa Fernandes de Farias, Eric Renato Lima Figueiredo, Raimundo Nelson Souza da Silva, Deizyane dos Reis Galhardo, Cleide Laranjeira da Silva, Evelyn Myelle Farias Moreira, Yury Souza de Azevedo, Emilly Cassia Soares Furtado, Janielly Reis Castelhano, João Simão de Melo-Neto and Fabiana de Campos Gomes

Trop. Med. Infect. Dis. 2025, 10(2), 41; https://doi.org/10.3390/tropicalmed10020041 - 31 Jan 2025

Abstract

Introduction: Human malaria is a zoonosis considered a serious global public health problem caused by five species of protozoa of the genus Plasmodium spp., which are transmitted by mosquito vectors belonging to the genus Anopheles spp. Objective: To verify whether there is a [...] Read more.

Introduction: Human malaria is a zoonosis considered a serious global public health problem caused by five species of protozoa of the genus Plasmodium spp., which are transmitted by mosquito vectors belonging to the genus Anopheles spp. Objective: To verify whether there is a relationship between the age-standardized malaria mortality rate in Brazil and age–period–cohort effect variables, sociodemographic differences, and indicators of sustainable development. Methods: Data on malaria mortality in Brazil from 2000 to 2022 were analyzed using sociodemographic factors such as ethnicity, region of residence, and sustainable development indicators. Results: Statistical data demonstrated that from 2000 to 2022, there was a reduction in malaria mortality; the 0–4 years age group was more susceptible to death, and the infection affected more men, Indigenous people, and residents of the North Region. Environmental factors such as CO₂ emissions and sanitation predict mortality in specific regions. The North and Northeast Regions had higher mortality rates. In the North, low CO₂ emissions, deforestation, weak urban sanitation, a lower GDP, and a higher Gini index were related to high mortality; the latter was also a factor in high rates of deforestation and solid waste collection in the Central West and Northeast Regions. The number of consultations and professionals was a predictive factor for high rates in the three regions mentioned. The Southeast Region had the lowest mortality rate and lowest health expenditure, while the Northeast and Midwest Regions had the highest expenditure in this sector. Conclusions: This study can contribute to the direction of public policy due to the specificities of each region in Brazil. Full article

(This article belongs to the Special Issue Recent Progress in Mosquito-Borne Diseases)

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9 pages, 638 KiB

Open AccessArticle

Utility of VIDAS^® Dengue Diagnostic Assays to Differentiate Primary and Secondary Dengue Infection: A Cross-Sectional Study in a Military Hospital from Colombia

by Andrés E. Prieto-Torres, Leidy J. Medina-Lozano, Juan David Ramírez-Ávila and Álvaro A. Faccini-Martínez

Trop. Med. Infect. Dis. 2025, 10(2), 40; https://doi.org/10.3390/tropicalmed10020040 - 29 Jan 2025

Abstract

This study aimed to assess the diagnostic utility of VIDAS^® DENGUE NS1 Ag and anti-DENV IgM and IgG assays in parallel for an early and accurate diagnosis and classification of dengue virus (DENV) infection. For this retrospective cross-sectional study, 190 patients with [...] Read more.

This study aimed to assess the diagnostic utility of VIDAS^® DENGUE NS1 Ag and anti-DENV IgM and IgG assays in parallel for an early and accurate diagnosis and classification of dengue virus (DENV) infection. For this retrospective cross-sectional study, 190 patients with suspected dengue were tested using VIDAS^® NS1, IgM, and IgG assays, requested in parallel, regardless of symptom onset timing, and classified into primary and secondary infections. Results were analyzed to determine diagnostic accuracy and correlation with disease severity. Parallel testing effectively differentiated between primary and secondary DENV infection. Secondary dengue cases with warning signs showed significantly elevated IgG levels (p = 0.026). Notably, NS1-negative (possible secondary cases) had higher IgM and IgG levels than NS1-positive cases (p < 0.01), suggesting that NS1 negativity might indicate an amplified immune response. In conclusion, VIDAS^® Dengue diagnostic assays not only enhance the diagnostic accuracy of dengue infection but also offer valuable insights into serological patterns, especially in secondary cases. These assays could be used not only to confirm diagnosis but also to stratify patients by risk, particularly in cases of secondary dengue, where IgG levels might indicate a higher risk for severe outcomes. Full article

(This article belongs to the Section Infectious Diseases)

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13 pages, 1384 KiB

Open AccessArticle

Intensive Therapeutic Plasma Exchange—New Approach to Treat and Rescue Patients with Severe Form of Yellow Fever

by Yeh-Li Ho, Youko Nukui, Paula Ribeiro Villaça, Erica Okazaki, Nelson Hidekazu Tatsui, Lucas Chaves Netto, Daniel Joelsons, Tania Rubia Flores da Rocha, Fernanda de Mello Malta, João Renato Rebello Pinho, Aluisio Augusto Cotrim Segurado and Vanderson Rocha

Trop. Med. Infect. Dis. 2025, 10(2), 39; https://doi.org/10.3390/tropicalmed10020039 - 29 Jan 2025

Abstract

Background: Severe yellow fever (YF) can result in acute liver failure (ALF) and high mortality. The role of therapeutic plasma exchange (TPE) in managing YF-ALF remains unclear. This study evaluated the impact of TPE strategies in severe YF. Methods: This observational case-series study [...] Read more.

Background: Severe yellow fever (YF) can result in acute liver failure (ALF) and high mortality. The role of therapeutic plasma exchange (TPE) in managing YF-ALF remains unclear. This study evaluated the impact of TPE strategies in severe YF. Methods: This observational case-series study evaluated three groups of patients classified according to treatment: G1 (standard intensive care support [ICS]), G2 (ICS + high-volume-TPE [HV-TPE]), and G3 (ICS + intensive TPE). HV-TPE was performed during 3 consecutive days with extra sessions of one plasma-volume, if necessary, whereas intensive TPE consisted of one plasma volume/session performed twice daily, with additional fresh frozen plasma infusion. Hemostatic agents, including tranexamic acid, platelets, and cryoprecipitate, were administered as needed. TPE was de-escalated based on clinical and laboratory parameters. The primary outcome was mortality. Results: Sixty-six patients were included (G1: 41, G2: 11, G3: 14). Groups had similar baseline characteristics. Mortality was significantly lower in G3 (14%) compared to G2 (82%) and G1 (85%) (p < 0.001). Additionally, G3 patients showed a higher frequency of undetectable YF viral load. Conclusions: Intensive TPE is a feasible and effective intervention for severe YF, achieving an 84% reduction in mortality. The limitations of our results are the small sample size, observational and single-center study. Further studies are warranted to elucidate intensive TPE’s role in YF management. Full article

(This article belongs to the Section Vector-Borne Diseases)

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16 pages, 930 KiB

Open AccessArticle

Biting Hour and Host Seeking Behavior of Aedes Species in Urban Settings, Metema District, Northwest Ethiopia

by Wondmeneh Jemberie, Sisay Dugassa and Abebe Animut

Trop. Med. Infect. Dis. 2025, 10(2), 38; https://doi.org/10.3390/tropicalmed10020038 - 28 Jan 2025

Abstract

Background: Aedes species transmit arboviral diseases, such as dengue, chikungunya, yellow fever, and Zika. The diseases cause severe sickness, mortality, and economic losses. This study describes the biting hour and host-seeking behavior of Ae. aegypti and Ae. vittatus in three towns. Recently, chikungunya [...] Read more.

Background: Aedes species transmit arboviral diseases, such as dengue, chikungunya, yellow fever, and Zika. The diseases cause severe sickness, mortality, and economic losses. This study describes the biting hour and host-seeking behavior of Ae. aegypti and Ae. vittatus in three towns. Recently, chikungunya and dengue infections were reported in the study sites. Methods: Biting hour and host-seeking behaviors of Ae. aegypti and Ae. vittatus were studied from June to September 2023, in Genda-Wuha, Kokit, and Metema-Yohannes towns, Metema district, Northwest Ethiopia. CDC-LT traps were set running indoors and outdoors for 24 h closer to humans sleeping inside unimpregnated mosquito nets. At the same time, CDC-LT traps were set running overnight closer to domestic animals’ shelters located within a 50-m radius of the main residence. Mosquitoes trapped in CDC-LT were collected every hour. The study was conducted four times in each town during the wet season. A chi-square test was employed to examine biting hour and host-seeking behavior. Results: Aedes aegypti was observed to be highly exophilic and active during the daylight hours. Aedes aegypti exhibited a peak biting rate between 07:00 and 08:00 with the biting rate of 4.5/person/hour followed by from 17:00 pm to 18:00 pm with the biting rate of 3.75/person/hour. The hourly biting rate of Ae. aegypti differed significantly. Its peak indoor biting rate was from 19:00 to 20:00 with the rate of 2.00 bites/person/hour followed by from 08:00 to 09:00 with the rate of 1.50 bites/person/hour and the biting rates differed significantly across the hours (F = 240.046; p = 0.001). Aedes vittatus also exhibited a biting rate similar to that of Ae. aegypti. Both Ae. aegypti and Ae. vittatus were abundantly collected from nearby human sleeping arrangements than from the shelters of cattle, sheep, goats, and donkeys. The highest proportions of Ae. aegypti (91.21%) and Ae. vittatus (89.87%) were unfed. Conclusions: Aedes aegypti and Ae. vittatus exhibited peak biting rates during morning and early night hours that aligned with the active daily routine practices of the local community. This could potentially expose the inhabitants to viral diseases transmitted by Ae. aegypti and Ae. vittatus. Full article

(This article belongs to the Special Issue Mosquito-Borne Diseases: Intervention Strategies Used to Control Mosquito Populations and Reduce Disease Transmission)

11 pages, 2214 KiB

Open AccessCase Report

Central Nervous System Infection by Free-Living Nematode Cephalobus cubaensis in a Human Host in Africa

by Charlotte Sriruttan-Nel, Chelline Cairns, Shareen Boughan, Bhavani Moodley, Lisa Ming Sun, Wai Yin Chan, Arshad Ismail, Absalom Mwazha, Praniel Bennimahadeo, Nithendra Manickchund, Mthabisi Moyo, Thabani Nkwanyana, Mpumelelo Z. Msimang, Ahmed Essa, John Frean and Mahomed-Yunus Moosa

Trop. Med. Infect. Dis. 2025, 10(2), 37; https://doi.org/10.3390/tropicalmed10020037 - 28 Jan 2025

Abstract

Background: Human central nervous system infections due to free-living nematodes, although extremely rare, are usually fatal. Immunodeficiency has not been a feature of most of these cases, unlike the situation pertaining to disseminated Strongyloides stercoralis infection. Case report: An elderly immunocompetent man presented [...] Read more.

Background: Human central nervous system infections due to free-living nematodes, although extremely rare, are usually fatal. Immunodeficiency has not been a feature of most of these cases, unlike the situation pertaining to disseminated Strongyloides stercoralis infection. Case report: An elderly immunocompetent man presented with a history of tinnitus and otalgia, progressing to central nervous system involvement with confusion, weakness, and other neurological signs. Examination revealed a unilateral external auditory canal soft tissue mass and radiological evidence of ipsilateral temporal bone destruction and brain parenchymal disease. A biopsy of the ear canal mass revealed the presence of an unidentified nematode species, and treatment with anthelminthics was started. The patient’s clinical condition deteriorated and he died shortly after admission to the intensive care unit. The immediate cause of death was bronchopneumonia. During the autopsy, an extensive involvement of the right middle cranial fossa was found, with destruction of the squamous and petrous parts of the temporal bone. Results: We identified adult, larval, and egg stages of a free-living nematode in the antemortem external auditory canal tissue mass and the post-mortem brain samples. Polymerase chain reaction assays, with Sanger and whole-genome sequencing, identified Cephalobus cubaensis. This is a free-living species not previously known to be pathogenic to humans, although nematodes of the same genus have caused mastitis in horses. Conclusions: Microscopic appearance and the invasive behaviour of the pathogen evoked a putative diagnosis of Halicephalobus gingivalis, the most frequently reported free-living nematode infecting humans. However, this nematode’s size and anatomical features, and the clinical presentation and duration of illness, prompted the consideration of an alternative species. We speculate that an initial bacterial otitis externa provided the opportunity for colonization by the nematode from an environmental source and subsequent invasion. Full article

(This article belongs to the Section Infectious Diseases)

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9 pages, 1676 KiB

Open AccessArticle

HPV-51 or HPV-52 Infection Could Impair Sperm Quality in Infertile Patients: A Preliminary Study on Our Experience from North-Western Italy

by Claudia Omes, Mariangela Rienzi, Roberta Rossini, Manuela Piccinino and Rossella Elena Nappi

Trop. Med. Infect. Dis. 2025, 10(2), 36; https://doi.org/10.3390/tropicalmed10020036 - 28 Jan 2025

Abstract

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections in all genders worldwide. Its association with male infertility is deeply investigated, although there are conflicting data on the role of the virus in the impairment of semen quality and [...] Read more.

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections in all genders worldwide. Its association with male infertility is deeply investigated, although there are conflicting data on the role of the virus in the impairment of semen quality and reduced reproductive outcomes. In this study, we considered 335 semen samples of males (age: 37.63 ± 6.02 years) belonging to infertile couples who did not conceive a pregnancy after 12 months of unprotected intercourse. Residual semen samples, after routine sperm analysis, were used to amplify and type viral DNA. Positive or negative HPV semen samples were compared. In total, 42.51% (139/327) were positive for at least one HPV genotype, and in 54.68% (76/139), positivity was due to a high-risk (HR) genotype. The most prevalent was HPV-16 (16.55%) followed by HPV-52 (10.07%) and HPV-51 (7.91%). Overall, no significant differences emerged in terms of sperm concentration, sperm motility, and morphology between the two groups. However, a considerable reduction in sperm motility was found in the presence of HPV-51 or HPV-52. These data point to the importance of HPV screening in semen analysis to evaluate patients that might have a higher risk of infertility according to the type of HPV genotype. Full article

(This article belongs to the Special Issue Molecular Epidemiology of Human Papillomavirus Infection)

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11 pages, 1228 KiB

Open AccessBrief Report

Wide Variation of Aedes albopictus Genotypes First Introduced into Canary Islands Assessed by rDNA Internal Transcribed Spacer Region and mtDNA cox1 Sequencing and Cloning

by Alejandra De Elías-Escribano, Irene Serafín-Pérez, Patricio Artigas, Carolina Fernández-Serafín, Sara Rodríguez-Camacho, Beatriz Yanes-Manrique, Víctor González-Alonso, Santiago Mas-Coma, Jacob Lorenzo-Morales and María Dolores Bargues

Trop. Med. Infect. Dis. 2025, 10(2), 35; https://doi.org/10.3390/tropicalmed10020035 - 27 Jan 2025

Abstract

Aedes albopictus, one of the most rapidly spreading invasive mosquito species, has expanded from Asia to establish populations on every continent except Antarctica, showcasing exceptional adaptability, particularly in island environments. This study provides the first molecular characterization of Ae. albopictus in the [...] Read more.

Aedes albopictus, one of the most rapidly spreading invasive mosquito species, has expanded from Asia to establish populations on every continent except Antarctica, showcasing exceptional adaptability, particularly in island environments. This study provides the first molecular characterization of Ae. albopictus in the Canary Islands, Spain. Genotyping was conducted using rDNA 5.8S-ITS2 and mtDNA cox1 sequencing, with haplotype analysis and phylogenetic network assessment. Among 49 sequences, 28 distinct 5.8S-ITS2 haplotypes were identified, with individual specimens containing 5 to 17 haplotypes (mean, 10.6). Most haplotypes (26/28; 92.85%) were unique to Tenerife, while only two (7.14%) were shared with other regions. H1 was the most frequent haplotype, shared with Valencia and China, while H2, a short-length haplotype, was shared with Mallorca. For cox1, only two haplotypes were detected: cox1-H1, reported in Europe, China, and Brazil, and a novel haplotype, cox1-H28. This genetic diversity suggests the species’ potential capacity to colonize new environments. The findings provide a foundation for further research in the Canary Islands and globally, particularly in regions with high tourism and arbovirus risks, emphasizing the importance of ongoing surveillance and genetic studies to understand the dynamics and public health impacts of invasive mosquito species. Full article

(This article belongs to the Special Issue Mosquito-Borne Diseases: Intervention Strategies Used to Control Mosquito Populations and Reduce Disease Transmission)

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12 pages, 657 KiB

Open AccessArticle

Epidemiological Dynamics and Trends of Dengue Outbreaks in Sao Tome and Principe: A Comprehensive Retrospective Analysis (2022–2024)

by Sousa Lazaro, Vilfrido Santana Gil, Ivando Carvalho Viegas de Ceita, Isaulina Neto Viegas Barreto, Eula Carvalho Batista Sousa Maquengo, Andreza Batista de Sousa, Bakissy da Costa Pina, Tieble Traore, Alimuddin Zumla and John Otokoye Otshudiema

Trop. Med. Infect. Dis. 2025, 10(2), 34; https://doi.org/10.3390/tropicalmed10020034 - 24 Jan 2025

Abstract

Background: Dengue has emerged as a significant public health concern in Sao Tome and Principe, with the first documented outbreak occurring between 2022 and 2024. This study examined the epidemiological patterns, environmental determinants, and demographic characteristics of dengue transmission during this period. Methods: [...] Read more.

Background: Dengue has emerged as a significant public health concern in Sao Tome and Principe, with the first documented outbreak occurring between 2022 and 2024. This study examined the epidemiological patterns, environmental determinants, and demographic characteristics of dengue transmission during this period. Methods: We conducted a comprehensive retrospective analysis of laboratory-confirmed dengue cases using national surveillance data, clinical records, and environmental monitoring data. Statistical analyses included demographic profiling, temporal trend assessment, and environmental correlation studies using multiple regression modeling. Results: Among 1264 laboratory-confirmed cases, we observed distinct age-specific vulnerability patterns, with the highest incidence rate in the 70–79 age group (829.6 per 100,000) despite most cases occurring in younger adults. Rainfall emerged as the strongest predictor of dengue transmission (r = 0.96, p < 0.001), explaining 92% of case variance in the regression model. Case distribution showed marked temporal variation, with 91.9% of cases reported in 2022, coinciding with exceptional rainfall (3205 mm). The overall case fatality rate was 0.71% (95% CI: 0.33–1.35), with significant quarterly variations. Geographical analysis revealed concentration in the Água Grande district (68.2% of cases). Conclusions: This first comprehensive analysis of dengue in Sao Tome and Principe demonstrates the crucial role of rainfall in disease transmission and reveals important age-specific vulnerability patterns. These findings provide an evidence base for developing targeted interventions, particularly during high-rainfall periods, and suggest the need for age-stratified clinical protocols in similar island settings. Full article

(This article belongs to the Special Issue Emerging and Re-emerging Infectious Diseases: Global and Local Burden, Surveillance, and Response Strategies)

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10 pages, 215 KiB

Open AccessArticle

Comparison of AccuPower Diarrhea V1&V2 RT-PCR to a Chromatographic Immunoassay for Detecting Viral Pathogens from Human Diarrheal Stool Specimens

by Luka Katic, Boris Mihaljevic, Marijo Pirija, Ivana Goic-Barisic, Marija Tonkic and Anita Novak

Trop. Med. Infect. Dis. 2025, 10(2), 33; https://doi.org/10.3390/tropicalmed10020033 - 24 Jan 2025

Abstract

Viruses are a frequent cause of self-limited diarrhea, with more severe outcomes in immunocompromised patients. This study aimed to compare the performance of Real-Time RT-PCR to chromatographic immunoassays (CIAs) for detecting the major gastrointestinal viruses in human stool. This study was conducted at [...] Read more.

Viruses are a frequent cause of self-limited diarrhea, with more severe outcomes in immunocompromised patients. This study aimed to compare the performance of Real-Time RT-PCR to chromatographic immunoassays (CIAs) for detecting the major gastrointestinal viruses in human stool. This study was conducted at the University Hospital of Split, Croatia, from October 2023 to May 2024. Stool samples were simultaneously analyzed with CIA (Acro Biotech Rotavirus and Adenovirus Combo Rapid Test Cassette, USA and JusChek Norovirus Rapid Test Cassette, China) and Real-Time RT-PCR (AccuPower Diarrhea V1&V2 Real-Time RT-PCR, Bioneer, Republic of Korea), according to the manufacturers’ instructions. Positive percent agreement (PPA), negative percent agreement (NPA), and overall percent agreement (OPA) were calculated. For norovirus, CIA had a low PPA (25%), indicating that it missed 75% of norovirus-positive cases identified by RT-PCR. Adenovirus detection by CIA showed poor agreement with RT-PCR (PPA 0%; NPA 100%). Rotavirus detection presented a relatively better performance with CIA (PPA 90.9% and OPA 84.13%). However, the presence of false positives (15.8%) highlights the need for confirmatory RT-PCR testing. One specimen was sapovirus-RT-PCR-positive, marking the first documented case from human specimens in Croatia. Although CIA provided rapid results, limitations regarding reliability highlight the value of RT-PCR, particularly in the case of ambiguous clinical cases with negative antigenic test results and newly emerged viruses. A two-step diagnostic approach, with initial CIA screening followed by confirmatory RT-PCR, could balance cost-effectiveness with diagnostic accuracy. Full article

(This article belongs to the Special Issue The Epidemiology, Diagnosis and Treatment of Foodborne and Waterborne Diseases)

14 pages, 1266 KiB

Open AccessSystematic Review

Molecular Detection of Mycobacterium leprae and the Process of Infection and Illness in Contacts of Leprosy Patients: A Systematic Review

by Sarah Lamas Vidal, Lavínia Cássia Ferreira Batista, Daniele dos Santos Lages, Bruna Eduarda Bortolomai, Isabela de Caux Bueno, Eyleen Nabyla Alvarenga Niitsuma, Nathan Guilherme de Oliveira, Ida Maria Foschiani Dias Baptista and Francisco Carlos Félix Lana

Trop. Med. Infect. Dis. 2025, 10(2), 32; https://doi.org/10.3390/tropicalmed10020032 - 23 Jan 2025

Abstract

Various techniques have been used for the molecular identification of Mycobacterium leprae (M. leprae). The aim of this review was to identify the relationship between the molecular presence of M. leprae and the process of infection and/or illness of contact of [...] Read more.

Various techniques have been used for the molecular identification of Mycobacterium leprae (M. leprae). The aim of this review was to identify the relationship between the molecular presence of M. leprae and the process of infection and/or illness of contact of leprosy cases. A systematic review was carried out by searching the Medical Literature Analysis and Retrieval System Online (MEDLINE), Cochrane Library, Embase, Scopus, Web of Science and the Latin American and Caribbean Health Sciences Literature (LILACS) databases in January 2024. The studies were selected by two pairs of reviewers. Observational cross-sectional, case–control and cohort studies were included. A descriptive synthesis of the results by category was carried out. A total of 443 studies were identified, and 36 were included in the review. Twelve molecular targets were tested to identify the presence of the bacillus. A relationship was established between the identification of M. leprae DNA and factors related to the index case, housing characteristics, living conditions, epidemiology and anti-PGL-1 serology. None of the studies identified evaluated the molecular viability of M. leprae among contacts. The detection of M. leprae DNA alone does not necessarily predict the development of infection or clinical illness among contacts. Full article

(This article belongs to the Special Issue Towards Zero Leprosy: Epidemiology and Prevention Strategy)

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13 pages, 3990 KiB

Open AccessArticle

Transcriptome Analysis of Culex pipiens quinquefasciatus Larvae Exposed to a Semi-Lethal Dose of Vermistatin

by Junhui Chen, Zhiyong Xu, Feiying Yang, Jian Yang, Wendong Kuang, Jianghuai Li, Guodong Niu, Jun Li, Yaqi Wang and Liang Jin

Trop. Med. Infect. Dis. 2025, 10(2), 31; https://doi.org/10.3390/tropicalmed10020031 - 22 Jan 2025

Abstract

Culex pipiens quinquefasciatus is a notorious vector transmitting severe diseases such as Zika virus and West Nile virus to humans worldwide. Vermistatin is a type of funicon-like compound and was first isolated from Penicillin vermiculatum in the 1970s. Vermistatin has shown promising activity [...] Read more.

Culex pipiens quinquefasciatus is a notorious vector transmitting severe diseases such as Zika virus and West Nile virus to humans worldwide. Vermistatin is a type of funicon-like compound and was first isolated from Penicillin vermiculatum in the 1970s. Vermistatin has shown promising activity against Cx. p. quinquefasciatus larvae in our previous research. Here, we conducted a transcriptomic analysis of Cx. p. quinquefasciatus larvae treated with a median lethal concentration of 28.13 mg/L vermistatin. Differential expression analysis identified 1055 vermistatin-responsive genes, with 477 downregulated and 578 upregulated. Gene Ontology annotation and enrichment analysis revealed the metabolic process to be the most significantly affected biological process, the membrane to be the most significantly affected cellular component, and catalytic activity to be the most significantly affected molecular function. Kyoto Encyclopedia of Genes and Genomes pathway analysis classified the differential expression genes into six major categories, with metabolism and organismal systems being the most enriched. Fifty-five pathways were significantly enriched, with the hematopoietic cell lineage, renin–angiotensin system, cholesterol metabolism, and peroxisome proliferator-activated receptor signaling pathways among the top altered pathways. Furthermore, 32 potential detoxification-related genes were differentially expressed, with 3 cytochrome P450s, 2 ABC transporters, and 1 UGT induced by vermistatin. This study provides insights into the molecular mechanisms of vermistatin’s action against Cx. p. quinquefasciatus larvae, highlighting potential targets for novel mosquito control strategies. Full article

(This article belongs to the Special Issue Insecticide Resistance and Vector Control)

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11 pages, 222 KiB

Open AccessBrief Report

A Retrospective Study of Clinical Biomarkers of Severe Dengue in a Tertiary Hospital in Johor Bahru, Malaysia

by Si Yin Kok, Ruth Elizabeth Abraham, Shareen Nisha Jauhar Ali, Wei Xuan Tuang and Edmund Liang Chai Ong

Trop. Med. Infect. Dis. 2025, 10(2), 30; https://doi.org/10.3390/tropicalmed10020030 - 21 Jan 2025

Abstract

Management of severe dengue remains a clinical challenge. This retrospective study evaluated clinical features and laboratory biomarkers associated with severe dengue at Hospital Sultanah Aminah Johor Bahru from 1 January 2022 to 31 March 2023. Records of 99 patients, categorized into ICU (51) [...] Read more.

Management of severe dengue remains a clinical challenge. This retrospective study evaluated clinical features and laboratory biomarkers associated with severe dengue at Hospital Sultanah Aminah Johor Bahru from 1 January 2022 to 31 March 2023. Records of 99 patients, categorized into ICU (51) and non-ICU (48) groups, were identified and analyzed using SPSS version 28.0. Sociodemographic details, clinical features and laboratory biomarkers were collected. Patients aged 50 and older, those with obesity, and those with pre-existing comorbidities were significantly more likely to be admitted to the ICU. The four most common warning signs in both cohorts were lethargy/restlessness/confusion, abdominal pain, persistent vomiting, and diarrhea. Fever, or history of fever, and thrombocytopenia were the two most common severe dengue criteria present in both cohorts. ICU patients exhibited more signs of plasma leakage and abnormal laboratory findings, including normal white cell count, hypoalbuminemia, hyperbilirubinemia, and elevated creatine kinase. In contrast, leukopenia and normal albumin, bilirubin, and creatine kinase levels were more common in non-ICU patients. Hyponatremia and raised lactate dehydrogenase were seen in both groups. This study highlighted key differences and similarities in clinical features and laboratory biomarkers between ICU and non-ICU patients, emphasizing the need for further research to develop a comprehensive risk assessment tool for predicting severe dengue that resulted in ICU admission. Full article

(This article belongs to the Section Neglected and Emerging Tropical Diseases)

30 pages, 1878 KiB

Open AccessReview

Schistosomiasis in the Philippines: A Comprehensive Review of Epidemiology and Current Control

by Emmanuel John Tabilin, Darren J. Gray, Mario A. Jiz, Mary Lorraine Mationg, Marianette Inobaya, Eleonor Avenido-Cervantes, Megumi Sato, Marcello Otake Sato, Yasuhito Sako, Yi Mu, Hong You, Matthew Kelly, Pengfei Cai and Catherine A. Gordon

Trop. Med. Infect. Dis. 2025, 10(2), 29; https://doi.org/10.3390/tropicalmed10020029 - 21 Jan 2025

Abstract

Schistosomiasis japonica is an infectious parasitic disease caused by infection with the blood fluke Schistosoma japonicum, which is endemic in China, small pockets of Indonesia, and the Philippines. Of the three countries, the prevalence of infection is the highest in the Philippines, [...] Read more.

Schistosomiasis japonica is an infectious parasitic disease caused by infection with the blood fluke Schistosoma japonicum, which is endemic in China, small pockets of Indonesia, and the Philippines. Of the three countries, the prevalence of infection is the highest in the Philippines, despite decades of mass drug administration (MDA). As a zoonosis with 46 potential mammalian definitive hosts and a snail intermediate host, the control and eventual elimination of S. japonicum requires management of these animal hosts in addition to new interventions for the human hosts, including health education and water, sanitation, and hygiene (WASH) infrastructure. In this review we examine the status and epidemiology of S. japonicum in the Philippines with an overview of the current control program there and what needs to be accomplished in the future to control and eliminate this disease in the country. Full article

(This article belongs to the Section Infectious Diseases)

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13 pages, 1532 KiB

Open AccessArticle

Innovations in TB Screening and Preventive Therapy Services for PLHIV in Yogyakarta City, Indonesia

by Dani Catrianiningsih, Guardian Yoki Sanjaya, Geoff Chan, Betty Weri Yolanda Nababan, Rina Triasih, Desthi Diah Intani and Endang Sri Rahayu

Trop. Med. Infect. Dis. 2025, 10(1), 28; https://doi.org/10.3390/tropicalmed10010028 - 20 Jan 2025

Abstract

Tuberculosis preventive therapy (TPT) for people living with HIV (PLHIV) has been recommended by Indonesia’s National TB Program since 2014 but has seen limited implementation. This study describes TB screening and TPT initiation from 2019 to 2022 among eight healthcare facilities supported by [...] Read more.

Tuberculosis preventive therapy (TPT) for people living with HIV (PLHIV) has been recommended by Indonesia’s National TB Program since 2014 but has seen limited implementation. This study describes TB screening and TPT initiation from 2019 to 2022 among eight healthcare facilities supported by the Zero TB Yogyakarta (ZTB) project. ZTB assigned a dedicated nurse to assist with active TB screening among PLHIV and recommended the immediate initiation of TPT as an innovation implemented. Data were obtained from the national HIV program reporting system, routinely reported by ART clinics from 2019 to 2022. We conducted a descriptive analysis, comparing the pre-intervention and intervention periods. During the intervention, there was a significant increase in PLHIV visits to healthcare facilities where TPT eligibility was assessed. At health centers, TB screening coverage for PLHIV decreased toward the end of the baseline period but recovered during the intervention. The number of PLHIV starting TPT also rose during the intervention. While the direct impact of ZTB is difficult to measure, the changes observed indicate progress in integrating TB/HIV services and enhancing TB prevention among PLHIV. Ongoing support, training, and supervision of healthcare facilities are crucial for improving TB screening and TPT provision. Full article

(This article belongs to the Special Issue Implementing TB Elimination Approaches in Indonesia: Operational Research on Case Finding, Treatment and Prevention of TB in Yogyakarta and Timika)

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11 pages, 433 KiB

Open AccessArticle

Estimation and Characterization of Dengue Serotypes in Patients Presenting with Dengue Fever at Makkah Hospitals

by Sami Melebari, Abdul Hafiz, Hatim A. Natto, Mohamed Osman Elamin, Naif A. Jalal, Ashwaq Hakim, Safiah Rushan, Othman Fallatah, Kamal Alzabeedi, Feras Malibari, Hutaf Mashat, Aisha Alsaadi, Amani Alhakam, Anoud Hadidi, Ghazi Saad Alkhaldi, Ahmed Alkhyami, Ali Alqarni, Abdulaziz Alzahrani, Mohammed Alghamdi, Abdullah Siddiqi, Abdullah Alasmari, Rowaida Bakri, Saleh Alqahtani, Juman M. Al-Bajaly and Asim Khogeer Show full author list Hide full author list

Trop. Med. Infect. Dis. 2025, 10(1), 27; https://doi.org/10.3390/tropicalmed10010027 - 20 Jan 2025

Abstract

Dengue fever is caused by four common serotypes of the dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4). Patients infected with one serotype may develop lifelong serotype-specific protective immunity. However, they remain susceptible to reinfection with the other serotypes, often increasing the risk of [...] Read more.

Dengue fever is caused by four common serotypes of the dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4). Patients infected with one serotype may develop lifelong serotype-specific protective immunity. However, they remain susceptible to reinfection with the other serotypes, often increasing the risk of severe forms of dengue. This cross-sectional study investigates the prevalence of the four dengue serotypes in patients who presented with dengue fever at Makkah hospitals between April 2023 and May 2024. Data were collected from the medical records of the Regional Laboratory in Makkah, Saudi Arabia. The 238 positive dengue samples included 185 samples (77.73%) from male patients. The average age of the patients was 37.65 years (SD = 15.05). Dengue type 2 was the most common serotype, followed by type 1, type 3, and type 4. Most of the dengue patients were Saudi nationals, followed by Egyptians. There were 11 dengue-positive samples that were not diagnosed with any of the four dengue serotypes. Since Makkah receives numerous international travelers, these samples might contain novel dengue serotypes circulating in different parts of the world. This study underscores the need for the continuous monitoring of dengue serotypes to predict potential outbreaks and mitigate the risk of severe dengue in susceptible populations. Full article

(This article belongs to the Special Issue Beyond Borders—Tackling Neglected Tropical Viral Diseases)

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16 pages, 329 KiB

Open AccessReview

Risk of Colonization with Multidrug-Resistant Gram-Negative Bacteria Among Travellers and Migrants: A Narrative Review

by Diogo Mendes Pedro, Daniela Santos, Maria Meneses, Fátima Gonçalves, Gonçalo Jantarada Domingos and Cátia Caneiras

Trop. Med. Infect. Dis. 2025, 10(1), 26; https://doi.org/10.3390/tropicalmed10010026 - 18 Jan 2025

Abstract

Globalization in the 21st century has posed several challenges. In particular, the spread of multidrug-resistant bacterial strains, especially Gram-negative bacteria, which are prevalent in certain regions of the world, is one of the most critical issues. This raises concerns about the risks associated [...] Read more.

Globalization in the 21st century has posed several challenges. In particular, the spread of multidrug-resistant bacterial strains, especially Gram-negative bacteria, which are prevalent in certain regions of the world, is one of the most critical issues. This raises concerns about the risks associated with the booming tourism industry and migratory flows. In fact, even transient colonization with multidrug-resistant strains can present significant challenges to individual, family, and public health. Understanding the epidemiology and mechanisms of resistance, associated risk factors and prevention policies is therefore essential to ensure that strategies are in place to limit the global spread of high-risk bacterial clones and thereby protect public health. Full article

(This article belongs to the Section Travel Medicine)

18 pages, 1183 KiB

Open AccessReview

The Global Challenge of Campylobacter: Antimicrobial Resistance and Emerging Intervention Strategies

by Zubeiru Bukari, Toyin Emmanuel, Jude Woodward, Richard Ferguson, Martha Ezughara, Nikhil Darga and Bruno Silvester Lopes

Trop. Med. Infect. Dis. 2025, 10(1), 25; https://doi.org/10.3390/tropicalmed10010025 - 16 Jan 2025

Abstract

Antimicrobial resistance (AMR) in Campylobacter species, particularly C. jejuni and C. coli, poses a significant public health threat. These bacteria, which are commonly found in livestock, poultry, companion animals, and wildlife, are the leading causes of foodborne illnesses, often transmitted through contaminated [...] Read more.

Antimicrobial resistance (AMR) in Campylobacter species, particularly C. jejuni and C. coli, poses a significant public health threat. These bacteria, which are commonly found in livestock, poultry, companion animals, and wildlife, are the leading causes of foodborne illnesses, often transmitted through contaminated poultry. Extensive exposure to antibiotics in human and veterinary medicine creates selection pressure, driving resistance through mechanisms such as point mutations, horizontal gene transfer, and efflux pumps. Resistance to fluoroquinolones, macrolides, and tetracyclines complicates treatment and increases the risk of severe infections. Drug-resistant Campylobacter is transmitted to humans via contaminated food, water, and direct contact with animals, highlighting its zoonotic potential. Addressing this challenge requires effective interventions. Pre-harvest strategies like biosecurity and immune-based methods reduce bacterial loads on farms, while post-harvest measures, including carcass decontamination and freezing, limit contamination. Emerging approaches, such as bacteriocins and natural antimicrobials, offer chemical-free alternatives. Integrated, multidisciplinary interventions across the food chain are essential to mitigate AMR transmission and enhance food safety. Sustainable agricultural practices, antimicrobial stewardship, and innovative solutions are critical to curbing Campylobacter resistance and protecting global public health. Our review examines the dynamics of antimicrobial resistance in Campylobacter and presents current strategies to mitigate Campylobacter-related AMR, offering valuable insights for antimicrobial control in the poultry industry. Full article

(This article belongs to the Special Issue The Epidemiology, Diagnosis and Treatment of Foodborne and Waterborne Diseases)

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14 pages, 1206 KiB

Open AccessArticle

Biological and Social Predictors of HIV-1 RNA Viral Suppression in ART Treated PWLH in Sub-Saharan Africa

by Sindhuri Gandla, Raja Nakka, Ruhul Ali Khan, Eliezer Bose and Musie Ghebremichael

Trop. Med. Infect. Dis. 2025, 10(1), 24; https://doi.org/10.3390/tropicalmed10010024 - 16 Jan 2025

Abstract

HIV remains a significant health issue, especially in sub-Saharan Africa. There are 39 million people living with HIV (PLWH) globally. Treatment with ART improves patient outcomes by suppressing the HIV RNA viral load. However, not all patients treated with ART suppress the HIV [...] Read more.

HIV remains a significant health issue, especially in sub-Saharan Africa. There are 39 million people living with HIV (PLWH) globally. Treatment with ART improves patient outcomes by suppressing the HIV RNA viral load. However, not all patients treated with ART suppress the HIV RNA viral load. This research paper explores the potential predictors of VL suppression in ART-treated PLWH. We used retrospective data from the 4820 ART-treated participants enrolled through population-based surveys conducted in Zambia and Malawi. We applied several machine learning (ML) classifiers and used the top classifiers to identify the predictors of VL suppression. The age of participants ranged from 15 to 64 years, with a majority being females. The predictive performance of the various ML classifiers ranged from 64% to 92%. In our data from both countries, the logistic classifier was among the top classifiers and was as follows: Malawi (AUC = 0.9255) and Zambia (AUC = 0.8095). Thus, logistic regression was used to identify the predictors of viral suppression. Our findings indicated that besides ART treatment status, older age, higher CD4 T-cell count, and longer duration of ART were identified as significant predictors of viral suppression. Though not statistically significant, ART initiation 12 months or more before the survey, urban residence, and wealth index were also associated with VL suppression. Our findings indicate that HIV prevention programs in the region should integrate education on early ART initiation and adherence in PLWH. Full article

(This article belongs to the Special Issue HIV Testing, Prevention and Care Interventions)

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15 pages, 622 KiB

Open AccessArticle

Laboratory Comparison of Rapid Antigen Diagnostic Tests for Lymphatic Filariasis: STANDARD Q Filariasis Antigen Test (QFAT) Versus Bioline Filariasis Test Strip (FTS)

by Patricia M. Graves, Jessica L. Scott, Alvaro Berg Soto, Antin Y. N. Widi, Maxine Whittaker, Colleen L. Lau and Kimberly Y. Won

Trop. Med. Infect. Dis. 2025, 10(1), 23; https://doi.org/10.3390/tropicalmed10010023 - 14 Jan 2025

Abstract

Accurate rapid diagnostic tests (RDTs) are needed to diagnose lymphatic filariasis (LF) in global elimination programmes. We evaluated the performance of the new STANDARD Q Filariasis Antigen Test (QFAT) against the Bioline Filariasis Test Strip (FTS) for detecting W. bancrofti antigen (Ag) in [...] Read more.

Accurate rapid diagnostic tests (RDTs) are needed to diagnose lymphatic filariasis (LF) in global elimination programmes. We evaluated the performance of the new STANDARD Q Filariasis Antigen Test (QFAT) against the Bioline Filariasis Test Strip (FTS) for detecting W. bancrofti antigen (Ag) in laboratory conditions, using serum (n = 195) and plasma (n = 189) from LF-endemic areas (Samoa, American Samoa and Myanmar) and Australian negative controls (n = 46). The prior Ag status of endemic samples (54.9% Ag-positive) was determined by rapid test (ICT or FTS) or Og4C3 ELISA. The proportion of samples testing positive at 10 min was similar for QFAT (44.8%) and FTS (41.3%). Concordance between tests was 93.5% (kappa 0.87, n = 417) at 10 min, and it increased to 98.8% (kappa 0.98) at 24 h. The sensitivities of QFAT and FTS at 10 min compared to the prior results were 92% (95% CI 88.0–96.0) and 86% (95% CI 80.0–90.0), respectively, and they increased to 97% and 99% at 24 h. Specificity was 98% for QFAT and 99% for FTS at 10 min. Both tests showed evidence of cross-reaction with Dirofilaria repens and Onchocerca lupi but not with Acanthochilonema reconditum or Cercopithifilaria bainae. Under laboratory conditions, QFAT is a suitable alternative RDT to FTS. Full article

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