Travel Medicine and Infectious Disease
○ Elsevier BV
Preprints posted in the last 90 days, ranked by how well they match Travel Medicine and Infectious Disease's content profile, based on 15 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Huang, L.; Zheng, Y.; Gu, S.; Li, Z.; Li, F.; Gu, W.; Hu, L.
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BackgroundBoth hemorrhagic fever with renal syndrome (HFRS) and scrub typhus (ST) are acute zoonotic infectious diseases. There is an overlap in their epidemiological characteristics and clinical manifestations, posing challenges for early differential diagnosis. This study aims to identify predictive factors for these two diseases to provide a basis for early diagnosis. Method/FindingsA retrospective analysis was conducted on the clinical data of patients diagnosed with HFRS and ST at the First Affiliated Hospital of Dali University. Logistic regression analysis was employed to explore independent risk factors for the early differential diagnosis of these two diseases, and a nomogram model was constructed based on these risk factors. The performance of the model was evaluated using the area under the receiver operating characteristic curve (AUC). The nomogram was utilized to visually present the predictive variables. Decision curve analysis (DCA) was performed to assess the clinical utility of the model. ResultsA total of 235 patients each with HFRS and ST were included in this study. After adjusting for confounding factors, the results of multivariate logistic regression analysis revealed that sex (male) (adjusted odds ratio [ajOR]: 2.093, 95% confidence interval [CI]: 1.107 - 3.957, P = 0.018), positive proteinuria (ajOR: 4.937, 95% CI: 2.427 - 10.042, P < 0.001), creatinine (CREA) (ajOR: 1.009, 95% CI: 1.003 - 1.015, P = 0.005), heart rate (ajOR: 0.981, 95% CI: 0.966 - 0.997, P = 0.018), and conjunctival congestion (ajOR: 16.167, 95% CI: 5.326 - 49.072, P < 0.001) were independent risk factors for differentiating HFRS from ST. The AUC of the model constructed based on these five independent risk factors was 0.856. ConclusionSex (male), positive proteinuria, elevated CREA, decreased heart rate, and conjunctival congestion are effective predictive factors.
Bautista, A.; Moreno, G. C.; Jerez, D.; Rojas, M. d. P. P.; Moreno, J.; Maldonado, L. Y.; Rodriguez, Y. M. E.; Sanabria, O.; Palacios, J.; Sotelo, J. C. R.; Duarte, M. C.; Sabogal, E.; Jimenez, K.; Duarte, C.
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Introduction: Bacterial meningitis (BM) is a common bacterial infection of the central nervous system, and its incidence in children varies by age, with the highest rates observed in infants younger than two months old. Objective: To describe the etiology, epidemiology, and clinical presentation of children under 5 years of age with BM at HOMI between 2016 to 2023. Materials and methods: Descriptive study of children under 5 years of age with suspected BM. Probable cases were those with CSF results consistent with BM. Confirmed cases had a positive CSF culture or blood culture for a bacterial pathogen or a positive molecular test for a bacterium in the CSF. Demographic variables, incidence of BM per year, mortality, and sequelae among survivors were analyzed. Results: A total of 527 suspected cases of BM were evaluated. Of these, 22.8% (120/527) were classified as probable cases and 13.1% (69/527) as confirmed cases. Children under 2 years of age accounted for 37.2% of probable cases and 78.2% of confirmed cases. Among confirmed cases, the most frequent symptoms were fever (98.3%), altered consciousness (39.1%), seizures (36.2%), and lethargy (27.5%). The mortality rate was 11.6% (8/69), and the mean hospital stay among patients with BM was 24.5 days. Streptococcus pneumoniae was identified in 26.1% of confirmed cases, with most isolates belonging to serotypes not included in PCV10. Haemophilus influenzae accounted for 17.4% of cases, of which 77.7% were serotype b. Neisseria meningitidis represented 10.1% of cases, and 60% of these were serogroup C. Other pathogens were identified in 49.1% of patients. Conclusion: Sentinel surveillance makes it possible to measure the impact of public health interventions and evaluate the impact of vaccines already used.
Nwofe, J. O.; Gbeyedobo, S. A.; Tarshi, M.; Ejiofor, Q. O.; Danson, P. W.; Aburke, A. B.; Onyebuchi, O. O.; Akyala, A. I.
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BackgroundDengue virus (DENV) is an increasingly recognized cause of febrile illness in sub-Saharan Africa, yet its epidemiology in Nigeria remains incompletely characterized due to fragmented surveillance and diagnostic variability. We conducted a systematic review and meta-analysis to estimate marker-specific seroprevalence and to evaluate geographic variation, seasonal patterns, and environmental risk factors associated with DENV infection in Nigeria between 2014 and 2024. MethodsFollowing PRISMA guidelines, we searched PubMed, Scopus, Web of Science, EMBASE, Google Scholar, and African Index Medicus for studies reporting laboratory-confirmed dengue infection in Nigeria. Random-effects meta-analysis was used to estimate pooled prevalence and pooled odds ratios (ORs) with 95% confidence intervals (CIs). Between-study heterogeneity was quantified using the I{superscript 2} statistic. Subgroup analyses explored variation by diagnostic marker and geographic region. ResultsThirty-three studies met inclusion criteria. The pooled random-effects IgM seroprevalence was 20.9% (95% CI: 13.0-30.1; I{superscript 2} = 98.6%), while pooled IgG seroprevalence was 19.9% (95% CI: 11.6-29.7; I{superscript 2} = 97.7%). NS1 antigen positivity was 8.9% (95% CI: 2.2-19.4), and PCR-confirmed infection was 7.0% (95% CI: 1.2-16.2; I{superscript 2} = 25.8%). Significant differences were observed across diagnostic markers (p = 0.0002). Regional subgroup analysis demonstrated statistically significant geographic variation for both IgM (p = 0.0179) and IgG (p = 0.0030), with highest pooled prevalence observed in the Southeast and lowest in the Southsouth region. Environmental and behavioral exposures were strongly associated with seropositivity, including proximity to refuse dumpsites (OR = 9.39, 95% CI: 7.44-11.84), non-use of mosquito nets (OR = 8.70, 95% CI: 5.73-13.21), malaria positivity (OR = 5.54, 95% CI: 3.84-7.98), and open household water storage (OR = 2.18, 95% CI: 1.65-2.89). All four DENV serotypes were identified across reporting studies. Transmission intensity increased during rainy seasons. ConclusionsDengue virus transmission in Nigeria is widespread and geographically heterogeneous, with evidence of both recent and cumulative exposure. Strong associations with modifiable environmental and household-level factors underscore the importance of integrated vector control and improved diagnostic capacity. Enhanced surveillance and climate-informed public health strategies are essential to mitigate future outbreak risk. Author SummaryDengue is a mosquito-borne viral infection that is increasing globally but remains underrecognized in much of sub-Saharan Africa. In Nigeria, many febrile illnesses are presumed to be malaria, which can obscure the contribution of dengue virus infection. In addition, limited surveillance systems and inconsistent diagnostic testing have made it difficult to determine the true extent of dengue transmission. To address this gap, we conducted a systematic review and meta-analysis of studies published between 2014 and 2024 to evaluate patterns of dengue exposure, geographic variation, and environmental risk factors in Nigeria. We found evidence of both recent infection (IgM antibodies) and past exposure (IgG antibodies) across multiple regions of the country. Transmission intensity varied geographically, with higher levels observed in some regions, particularly in the Southeast, and lower levels in the Southsouth. Infection risk increased during the rainy season, consistent with enhanced mosquito breeding conditions. Living near refuse dumpsites, storing water in open containers, not using mosquito nets, and having malaria were all associated with higher odds of dengue infection, highlighting the importance of household and environmental conditions in shaping transmission risk. All four dengue virus serotypes were identified, indicating sustained viral circulation. These findings demonstrate that dengue virus infection is widespread in Nigeria and influenced by modifiable environmental and behavioral factors. Improving diagnostic capacity, strengthening routine surveillance, and implementing targeted vector control strategies are essential to reduce transmission and improve outbreak preparedness.
Zhang, T.; Wei, Q.; Schmit, N.
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Incidence patterns of post-acute sequelae, characterised by persistence or delayed onset after the acute phase of an infection, are not well documented after infectious disease outbreaks. Nipah virus was first detected in the 1998-1999 Malaysia outbreak and remains a significant public health concern due to its high epidemic potential and recurrent outbreaks in South Asia. We conducted a systematic review on the prevalence, incidence, duration, and characteristics of post-acute sequelae in survivors of Nipah virus infection. We searched PubMed and Web of Science for studies published up to November 17, 2025. We included 8 articles, and extracted prevalence for 34 potential neurological, psychiatric or non-specific post-acute sequelae. The pooled prevalence of total residual neurological deficits was 24% (95% CI 9-49) among total survivors of Nipah infection, and 45% (95% CI 11-85) among the subset of survivors with acute Nipah encephalitis (5 articles). In the single controlled study, total residual neurological deficits, fatigue and daytime somnolence were significantly more prevalent in Nipah infection survivors than population-based controls. We estimated that 10% (95% CI 4-20) of Nipah infection survivors also experience late-onset or relapsing neurological symptoms after initial recovery. These findings demonstrate a substantial long-term disease burden following Nipah virus infection, which should be accounted for in mathematical modelling studies. However, the estimates are mainly based on data from the Malaysia/Singapore outbreak and may not be generalisable to the Bangladeshi and Indian setting, where current outbreaks occur and are caused by a different viral strain. Further limitations relate to subjective outcome assessment and heterogeneous populations of total Nipah infection survivors, which could have biased our estimates.
Wu, S.; Wang, J.; Ye, W.; Lin, Y.; Guo, Z.; Weng, Y.; Han, J.
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BackgroundDengue fever is a major neglected tropical disease with a rapidly rising global burden, and localized outbreaks are increasingly reported in southern subtropical China. Fujian Province, a coastal subtropical region with favorable ecological conditions for Aedes albopictus breeding and frequent cross-border exchanges with dengue-endemic areas, has had continuous local dengue cases for over a decade, raising concerns about the establishment of a stable natural endemic focus. Sustained local dengue transmission is defined by four core criteria, but no systematic assessment of these criteria has been conducted for Fujian using long-term multi-dimensional surveillance data. We aimed to evaluate whether a natural endemic focus for sustained local dengue transmission has been established in Fujian Province from 2014 to 2024 using four core evidence dimensions. MethodsWe extracted data on imported and locally acquired dengue cases in Fujian from 2014 to 2024 from Chinas National Notifiable Disease Reporting System (NNDRS). Serological surveillance for dengue IgG antibodies and virological surveillance for dengue virus in Aedes albopictus were conducted at seven sentinel sites. The study period was stratified into three phases based on the impact of COVID-19 non-pharmacological interventions: pre-pandemic (2014-2019), pandemic(2020-2022), and post-pandemic(2023-2024). Descriptive epidemiological analysis and data visualization were performed using R software (version 4.4.1), with t-tests for continuous variables and {chi}{superscript 2} tests for categorical variables. ResultsA total of 3,606 dengue cases were reported in Fujian during the study period, including 1,229 imported and 2,377 locally acquired cases. Key findings were as follows: (1) Temporal distribution: Local dengue transmission was completely interrupted during the 2020-2022 COVID-19 pandemic (0 local cases, only 26 imported cases), and resumed at a low level in 2023-2024 (160 local cases). (2) Serology: The overall population dengue IgG antibody positivity rate was 4.2% (66/15,736), with no statistically significant difference between pre-epidemic (3.8%, 30/7,835) and post-epidemic seasons (4.5%, 36/7,901; P=0.48), and no year with a positivity rate exceeding 10%. (3) Vector surveillance: Only one dengue virus-positive sample was detected among 385,000 Aedes albopictus mosquitoes collected during routine surveillance (Taijiang District, Fuzhou, October 2017), with no viral nucleic acid detected in all other samples. (4) Age distribution: The mean age of locally acquired cases (46.1{+/-}19.8 years) was significantly higher than that of imported cases (35.8{+/-}11.2 years, P<0.001), and local cases were concentrated in the middle-aged group (40-60 years) with no child-dominant pattern observed. ConclusionsFujian Province has not established a stable natural endemic focus for sustained local dengue transmission, and imported cases are the primary driver of local outbreaks in the region. Strengthened surveillance and early management of imported cases, integrated vector control targeting Aedes albopictus, and targeted public health education are critical and essential strategies to prevent the establishment of a dengue natural endemic focus in Fujian and other subtropical coastal regions with similar epidemiological characteristics. Author SummaryDengue fever is a rapidly spreading neglected tropical disease worldwide, and southern China faces persistent threats of local transmission due to favorable ecological conditions for mosquito breeding and frequent cross-border travel. Fujian Province, a subtropical coastal region in southeastern China, has reported annual local dengue cases for over a decade, raising public health concerns about the potential establishment of a stable natural endemic focus--where the virus circulates sustainably without relying on imported cases. To address this critical question, we conducted a comprehensive 11-year assessment (2014-2024) of dengue transmission in Fujian using four key evidence dimensions defined for identifying dengue endemic foci: the continuity of local cases independent of imported sources, population antibody levels, dengue virus detection in local mosquitoes (Aedes albopictus), and the age distribution of infected patients. We also leveraged the COVID-19 pandemic(2020-2022) as a unique natural experiment, during which strict travel restrictions drastically reduced imported dengue cases, to test whether local transmission could persist on its own. Our findings showed that local dengue transmission in Fujian completely stopped during the COVID-19 pandemic and only resumed when cross-border travel and imported cases recovered, confirming local transmission is entirely dependent on imported virus sources. Additionally, the local population had a very low dengue antibody positivity rate (4.2%), dengue virus was detected in only one mosquito sample over 11 years of surveillance, and local cases were concentrated in middle-aged adults (not children--the typical group affected in endemic areas). Together, these results confirm that Fujian Province has not established a stable natural endemic focus for dengue fever. While no endemic focus exists yet, Fujian remains at high risk of imported-driven local outbreaks due to its climate and cross-border exchanges. Our study highlights three critical strategies to prevent the future establishment of a dengue endemic focus in Fujian and other similar subtropical coastal regions: strengthening surveillance and early response for imported dengue cases, implementing targeted mosquito control measures during peak transmission seasons, and conducting public health education to raise awareness of dengue prevention. These evidence-based interventions are key to blocking the formation of sustained local dengue transmission and protecting regional population health.
Koulidiati, J.-L.; Zoma, R. L.; Nebie, E. I.; Soumaila, Y.; Neya, C. O.; Kiendrebeogo, J. A.; Debellut, F.
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Background: In Burkina Faso, typhoid fever remains a major public health concern, with a high incidence among children younger than 15 years of age. To address this burden, the country introduced typhoid conjugate vaccine in January 2025 through a national vaccination campaign reaching children aged 9 months to 14 years. This study aimed to estimate the cost of typhoid conjugate vaccine delivery during the national campaign and to identify the main cost drivers across different administrative levels. Methods: We conducted a cross-sectional, retrospective costing study using a microcosting approach from the government perspective. We collected data from fifty health facilities, eight health districts, five health regions, and the national level. Financial and economic costs were estimated for each level, excluding vaccine and syringe costs. All costs were converted to 2024 USD using the official exchange rate. Findings: Vaccinators administered a total of 10.5 million typhoid conjugate vaccine doses. The average financial cost per dose was $0.47 (95% CI: $0.39-$0.51), and the economic cost was $2.16 (95% CI: $1.71-$2.56). Human resources and per diem payments were the main contributors to costs. Costs varied by geography, delivery strategy, and security context, with higher costs observed in rural and conflict-affected areas. The mobile-temporary posts strategy had the highest economic cost per dose ($2.02; 95% CI: $1.64-$2.40), while the fixed strategy had the highest financial cost per dose ($0.41; 95% CI: ($0.32-$0.49). Conclusion: The financial cost per dose remained within Gavi, the Vaccine Alliance's operational support range. The observed cost variations highlight the need for targeted funding and enhanced logistical support to ensure equitable access, particularly in rural and insecure areas. This study provides evidence to inform future vaccination campaigns and supports decision-making for typhoid conjugate vaccine introduction in other countries in the region.
Salas-Lais, A.; Fernandes-Matano, L.; Torres-Flores, A.; Morales-Hernandez, M. L.; Lopez-Macias, C.; Martinez-Miguel, B.; Tepale-Segura, A.; Guerrero-Garcia, J. d. J.; Alvarado-Yaah, J. E.; Anguiano-Hernandez, Y. M.; Castro-Escamilla, O.; Zamudio-Chavez, O.; Herrera-Gomez, F. d. J.; Krug-Llamas, E.; Romero-Feregrino, R.; Santacruz-Tinoco, C. E.; Bonifaz, L. C.; Diaz-Jimenez, C.; Vargas-Garcia, A. M.; Munoz-Medina, J. E.; Santos-Carrillo, A. A.
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ObjectivesDespite the availability of effective vaccines, achieving the seroprevalence thresholds recommended by the World Health Organization (WHO) for eliminating measles, rubella, and mumps remains a public health challenge. MethodsA retrospective, cross-sectional serological survey was conducted, including 9,587 serum samples collected from 31 of the 32 federal entities of Mexico between September and December 2024. IgG antibody levels against measles, rubella, and mumps were quantified using chemiluminescent immunoassays. Seroprevalence was analyzed by age, sex, and geographic region. ResultsThe overall seroprevalence was 78.3% for measles, 88.6% for rubella, and 81.5% for mumps (p<0.05). Age-stratified analysis revealed significant gaps in immunity against measles and mumps, particularly in the 10-39-year-old group, in which seroprevalence dropped below 70%. In contrast, more consistent protection against rubella was observed across all age groups, although younger children showed lower antibody titers. Regional analysis indicated that only older adults reached the protective threshold against measles in all states. ConclusionsThis study demonstrates that current levels of seroprevalence in Mexico do not correspond to the vaccination coverage recommended by the WHO and highlights the urgent need to strengthen vaccination strategies, conduct catch-up campaigns, and carry out continuous seroepidemiological surveillance to maintain elimination goals.
Hossain, H.; Mohiuddin, A. S. M.; Islam, S.; Insan, M.; Ahmed, S.; Brishty, K. A.; Parvej, M.; Yadav, S. K.; Ahmed, S.; Das, S. R.; Rahman, M. M.; Rahman, M. M.; Paul, B.
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BackgroundAnimal bites represent a significant public health concern due to the risk of injuries and transmission of zoonotic diseases such as Rabies, particularly in low and lower- middle-income countries (LMICs). Understanding the epidemiological characteristics of animal bite incidents is essential for improving the prevention and control strategies. This study aimed to characterize the epidemiological patterns and characteristics of animal bite cases in Sylhet, Bangladesh. Methodology/Principal findingsWe conducted a retrospective analysis of 6,565 animal bite cases reported between January 1 and December 31, 2024, in Sylhet, Bangladesh. Data on demographic characteristics, type of biting animal, site of bite, and exposure category were collected and analyzed to determine associations using correlation analyses and chi-square tests. Among the victims, 3,917 (60%) were male and 2,648 (40%) were female and young adults aged 20-39 years comprised the largest group (39% of cases). The majority of cases (88.1%) originated from urban areas within Sylhet City Corporation. Cats were the leading cause of bites (56.6%), followed by dogs (35.0%) and monkeys (7.5%), suggesting a shift from the traditional dog-dominated pattern. The most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Most exposures were classified as World Health Organization (WHO) Category II (98.2%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. A significant declining temporal trend was observed for monkey bites (R = -0.59, p = 0.044), whereas cat and dog bite patterns remained relatively stable throughout the year. Significant associations were identified between bite site and age group, as well as between biting animal and demographic characteristics (p < 0.05). Conclusion/SignificanceThese findings highlight the epidemiological patterns of animal bites in Sylhet and emphasize the need for strengthened public awareness, surveillance, and preventive strategies to reduce animal bite incidents and associated zoonotic disease risks. SynnopsisO_LIA large-scale retrospective analysis of 6,565 animal bite cases revealed a cat-dominant bite pattern (56.6%), contrasting with the traditional dog-dominant paradigm in South Asia. C_LIO_LIYoung adults (20-39 years) and males (60%) were disproportionately affected, reflecting occupational and behavioral exposure risks. C_LIO_LIUrban residents (88.1%) accounted for the majority of cases, highlighting the growing public health burden of animal bites in rapidly urbanizing settings. C_LIO_LIThe most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. C_LIO_LICategory II exposures (98.2%) predominated, indicating a high burden of seemingly minor injuries that may be underestimated in rabies prevention strategies. C_LI
Zhong, S.; Wong, I. O. L.; Wu, P.; Cowling, B. J.
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BackgroundOlder adults face a disproportionately high risk of severe influenza, yet the standard inactivated vaccine (IIV) offers suboptimal protection in this population. This study evaluates the cost-effectiveness of replacing IIV with the recombinant influenza vaccine (RIV) for adults aged [≥]50, [≥]65, and [≥]80 years in Hong Kong. MethodsA decision tree model was used to compare RIV with IIV for adults aged [≥]50, [≥]65, and [≥]80 years in Hong Kong, from a societal perspective. Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were evaluated with the impact of parameter uncertainty on the results assessed via deterministic and probabilistic sensitivity analyses. ResultsFor adults [≥]50 years, RIV increased total costs by USD5.1 (HKD39.8) per person and gained 0.00012 QALYs (ICER: USD40,659 [HKD317,140] per QALY) compared to IIV. Among adults [≥]65 years, RIV cost USD6.0 (HKD46.8) more and gained 0.00021 QALYs (ICER: USD29,077 [HKD226,801] per QALY). For adults [≥]80 years, RIV cost USD3.2 (HKD25.0) more and gained 0.00015 QALYs (ICER: USD21,092 [HKD164,518] per QALY). ICERs were less than willingness-to-pay thresholds of one to three times Hong Kongs gross domestic product per capita. ConclusionsRIV is cost-effective compared with IIV for adults [≥]50, [≥]65, and [≥]80 years in Hong Kong, with the lowest ICER observed in individuals [≥]80 years.
Karichu, J. K.; Pennington, M.; Lander, K.; Smith, T. T.; Thornberg, A.
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Introduction Data on bloodstream infections (BSI) indicate a growth in incidence over time. This analysis utilised national data from England and the best available United States (US) evidence to predict BSI incidence over the years 2025 to 2029. The analysis utilised evidence on the cost-effectiveness of molecular rapid diagnostic tests (mRDT) to estimate the cost and mortality associated with BSI, and the potential for increased use of mRDT to save lives. Methods Data on BSI incidence by age group and sex for England in 2017 and the US (Minnesota) for 2003 to 2005 were combined with demographic projections over the years 2025 to 2029 to estimate the number of BSIs. Published costs and mortality associated with BSI, according to the method of identification of the pathogen, were used to estimate the lives saved and the cost impact of widespread use of mRDT in England and the US. Results BSI cases in England and the US are predicted to total 1.02 million and 6.24 million over the years 2025 to 2029, associated costs are GBP14.6 million and $221 million, respectively. Expanding the use of mRDT would save 2,219 and 7,554 lives in England and the US, respectively, over a 5-year period and would reduce healthcare expenditure in both countries. Conclusion There is a compelling argument to increase the uptake of mRDT to improve patient outcomes. This analysis demonstrates that expanded mRDT adoption can significantly reduce BSI burden, saving over 9,700 lives and decreasing healthcare expenditure in both countries.
Mac, V. V.; Wong, J. M.; Jones, E. S.; Biggerstaff, B. J.; Delorey, M.; Hitchings, M. D. T.; Madewell, Z. J.; Perez-Padilla, J.; Volkman, H. R.; Medina, F. A.; Munoz-Jordan, J.; Wakeman, B.; Wanga, V.; Drummond, A.; Joseph, J.; Gumbs, A.; Ellis, E. M.; Adams, L. E.
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ObjectiveTo estimate dengue virus (DENV) seroprevalence and assess parental vaccine perceptions among children in the US Virgin Islands (USVI). MethodsA cross-sectional serosurvey was conducted during April-May 2022 among 372 children aged 8-16 years from 15 schools across USVI. Past DENV infection was determined using a dengue IgG rapid diagnostic test. Data on demographics, dengue knowledge, and vaccine acceptance were collected from parents. Catalytic models estimated annual DENV force of infection (FOI) using seroprevalence and case data from 2010-2022. ResultsSeroprevalence among children aged 8-13 years was 47% (95% CI: 29%, 68%). FOI peaked during 2012-2013 outbreaks and remained low in other years. Only 17% of parents were aware of an approved dengue vaccine, and 25% reported they would vaccinate their child. ConclusionsNearly half of children had prior DENV infection. Despite this risk, parental awareness of dengue vaccination was low, underscoring gaps in detection, diagnosis, and preparedness for vaccine implementation. Policy ImplicationsThese data highlight the need for enhanced surveillance, public education, and targeted planning for dengue vaccine introduction in endemic US jurisdictions.
Halder, C. E.; Hasan, M. A.; Soma, E.; Charles Okello, J.; Rahman, M. M.; Das, P. P.; Prue, U. M.; Barasa, D. W.; Md, A.; Hosen, M. S.; Shagar, S. H.; CHONG, E. Y. C.; Paul, D.; Mowla, S. M. N.; Hoque, M.; Bhuiyan, A. T. M.; Hussain, M. F.
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Background: Dengue emerged as a new public health threat in the Rohingya refugee camps in Coxs Bazar, Bangladesh, in 2021 and expanded into large-scale upsurges in subsequent years. Evidence on dengue epidemiology and clinical presentation in protracted refugee settings remains limited, despite the need for stronger outbreak preparedness and case management in these contexts. Objectives: To describe the epidemiological, clinical, and diagnostic characteristics of the dengue upsurge among Rohingya refugees and surrounding host communities in Coxs Bazar, Bangladesh, and to identify predictors of inpatient admission and diagnostic positivity patterns. Methods: This retrospective observational study used anonymized surveillance data from the International Organization for Migration (IOM) dengue patient database. Rapid diagnostic test (RDT)-confirmed dengue cases identified across 36 IOM-supported health facilities in Ukhiya and Teknaf between 1 October 2021 and 31 December 2024 were included. Demographic, epidemiological, clinical, and laboratory variables were summarized using descriptive statistics. Weekly incidence was aggregated by epidemiological week and calendar year, and epidemic growth and decay phases were modelled using phase-specific Poisson regression. Multivariable logistic regression was used to identify predictors of inpatient admission and to examine associations between delay in presentation and RDT positivity patterns, adjusting for age and sex. Results: A total of 35,581 RDT-confirmed dengue cases were reported, of which 90.2% occurred among Rohingya refugees. The median age was 17 years (IQR 7-30), and 46.0% of cases were among children aged 0-14 years. Annual caseload increased from 1,011 in 2021 to 11,752 in 2022, 10,669 in 2023 and 12,149 in 2024, with seasonal peaks during the monsoon period and progressively later peaks and longer epidemic tails over time. Poisson models showed decreasing growth rates across years (r=0.449 in 2021 to r=0.091 in 2024) with increasing doubling times, while decay rates remained broadly comparable (halving time ~4.4-6.0 weeks). Overall, 8.0% of cases required inpatient admission, 1.3% were referred, and four deaths were reported (case fatality <0.1%). In multivariable analysis, inpatient admission was associated with older age ([≥]60 vs 0-14: aOR 2.31), delayed presentation (aOR 1.06 per day), refugee status (aOR 1.39), presence of any World Health Organization (WHO) warning sign (aOR 26.60), low systolic BP (aOR 2.84) and chronic co-morbidity (aOR 6.07). In addition, males had lower odds of admission than females (aOR 0.88). NS1 antigen alone was positive in 62.1% of cases, IgM alone in 33.6%, and dual positivity in 4.3%. Longer delay from symptom onset to presentation was strongly associated with IgM-only positivity compared with NS1-only positivity (adjusted models controlling for age and sex). Conclusion: Sustained dengue preparedness is required in Coxs Bazar, including strengthened surveillance, community-based early referral, targeted monitoring of high-risk groups, environmental vector control, and phase-appropriate use of NS1 and IgM/IgG diagnostics to reduce missed diagnoses and prevent progression to severe disease. These findings highlight the need for a policy shift from episodic outbreak response toward sustained dengue preparedness in humanitarian settings, including strengthened surveillance systems, integrated diagnostic strategies, community-based early referral, and coordinated vector control interventions.
Padhi, A.; Bera, J. H.; Rajyaguru, B.; Chauhan, J.; Rank, D.; Modasiya, I.; Bhalani, S.; Agarwal, A.
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BackgroundDengue virus infection remains a significant public health concern in India, with changing serotype dynamics influencing disease epidemiology. Understanding local serotype distribution and clinical characteristics is crucial for effective disease management and surveillance. ObjectivesTo determine the prevalence of dengue virus serotypes and analyze their clinical characteristics among NS1-positive patients at a tertiary-care hospital in Gujarat, India. MethodsA cross-sectional study was conducted on NS1-positive dengue patients admitted to AIIMS Rajkot from September 2023 to November 2024. Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed for serotype identification. Clinical and demographic data were collected and analyzed. ResultsNS1-positive patients (70) were confirmed by RT-PCR. DENV-2 was the predominant serotype (53 cases, 75.7%), followed by DENV-1 and DENV-3 (7 cases each, 10.0%), and DENV-4 (2 cases, 2.9%). One co-infection case (DENV-2 + DENV-3) (1.4%) was identified. The mean age was 27.7 {+/-} 14.4 years, with male predominance (58.6%). Young adults (19-35 years) were most affected (45.7%), followed by pediatric patients [≤]18 years (32.9%). Severe dengue occurred in only one case (1.4%), while hospitalization was required in 25 cases (35.7%). All patients presented with fever, chills, headache (50%), rashes (56%), and malaise (56%), being the most common associated symptoms. ConclusionsDENV-2 showed clear predominance in the Rajkot region during the study period, with low rates of severe disease. The significant pediatric and young adult involvement highlights the need for targeted prevention strategies. These findings contribute to the understanding of regional dengue epidemiology and support evidence-based surveillance and control measures.
Cheuyem, F. Z. L.; Achangwa, C.; Boukeng, L. B. K.; Tchamani, R.; Davies, J.; Malaka, C. N.; Mbarga, A. E.
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BackgroundAfrica continues to have a significant public health problem with mpox, where endemic transmission persists and overlaps with a high burden of other infectious diseases. Although their epidemiology and clinical impact are still poorly understood throughout the continent, coinfections with human immunodeficiency virus (HIV) and varicella-zoster virus (VZV) can affect the clinical picture, severity of the disease, and accuracy of the diagnosis. MethodsFollowing PRISMA criteria, we registered the protocol in PROSPERO (CRD420251133960) and carried out a methodical review and meta-analysis. Through searches of numerous electronic databases and grey literature up to February 27, 2025, observational studies documenting mpox coinfections with VZV and/or HIV and related clinical symptoms in Africa were searched. Pooled prevalence was calculated using random-effects models. Subgroup analyses and meta-regression were conducted to investigate heterogeneity across WHO regions, countries, study designs, settings and type of participants. ResultsA total of 27 studies carried out across African countries were included. The pooled prevalence of VZV-mpox coinfection was 10.23% (95% CI: 2.95-29.93), while HIV-mpox coinfection prevalence was 6.55% (95% CI: 2.36-16.90), both of which had significant heterogeneity. Coinfections were far more prevalent in hospital-based environments than in community-based research. The rash was nearly universal throughout all clades, but the clinical manifestations varied depending on the viral clade, with clades I and Ia linked to more severe systemic symptoms than clade II. DiscussionsHIV and VZV coinfections with mpox pose a major yet possibly underestimated burden in Africa and are linked to more severe clinical presentations, particularly in hospital environments. The necessity of including clinical, epidemiological, and genomic data into mpox monitoring systems is emphasized by the observed clinical differences between clades. Improving patient management and outbreak preparedness across the continent requires strengthening diagnostic capacity and routinely screening for coinfections.
Thuong, L. D. M.; Phan, L. T. M.; Dao, A. T.; Le, T. H.; Le, A. T.; Vo, T. T. T.; Dang, A. Q.; Do, L. T. T.; Pham, N. V.; Pham, H. T. C.; Nguyen, H. T. T.; Do, H. T.
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BackgroundRabies remains a cause of mortality in many low- and middle-income countries, with the majority of human infections resulting from dog-to-human transmission. The Integrated Bite Case Management (IBCM) model is a One Health approach that aims to strengthen rabies surveillance and response by linking the management of human bite cases with investigation of the implicated animals. This study aimed to evaluate the effectiveness of implementing IBCM in Quang Nam Province under existing resource conditions. Methodology/Principal FindingsA pre-post intervention study without a control group was conducted across the entire province. During the intervention period, 11,673 animal-bite cases were recorded; IBCM identified 75 animals suspected of having rabies, of which 40 tested positive for rabies virus by RT-PCR. Most of these animals were unvaccinated, free-roaming dogs. In communes where outbreaks were detected, the average number of registered dogs increased from 507 to 543 per commune, and vaccination coverage increased from 44.1% to 72.6% within 21 days. The average number of Post-exposure prophylaxis (PEP) courses administered per month increased from 349 to 971, the proportion of high-risk exposures increased from 9.3% to 11.9%, and the proportion of delayed PEP ([≥]10 days after exposure) rose slightly from 5.9% to 6.6%. At the same time, the proportion of staff with good knowledge of rabies diagnosis in animals increased substantially, from 9.1% to 55.6%. The main limitations included the pre-post design and loss to follow-up of some animals, which prevented laboratory testing. ConclusionThe implementation of IBCM within the existing health and veterinary systems substantially strengthened rabies surveillance and response in accordance with the One Health approach. IBCM was demonstrated to be feasible, resource-appropriate, and scalable, thereby contributing to progress toward the global goal of eliminating human deaths from dog-mediated rabies by 2030. Author summaryRabies is a preventable disease, yet it continues to cause deaths in many countries where dogs remain the primary reservoir and source of infection. In Vietnam, rabies surveillance remains largely separated between the human and animal health sectors. The IBCM model uses human bite cases as the "trigger point" for coordinated investigation of the implicated animals, risk assessment, and information sharing between the two sectors, thereby supporting both clinical decision-making and outbreak response. We implemented the IBCM model in Quang Nam Province and observed an increase in the number of rabid animals detected, a marked rise in dog vaccination coverage in outbreak-affected areas, and substantial improvement in the knowledge and capacity of both health and veterinary staff. Simply by strengthening collaboration and information sharing between the two sectors, the rabies surveillance system became more sensitive and effective. This represents a practical example of One Health approach in action.
Negretto Schrarstzhaupt, I.; Diaz-Quijano, F. A.
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BackgroundAlthough the impact of COVID-19 vaccination is widely documented in the general population, the evidence on its effectiveness in children under 5 years of age is still limited. In this context, the continuation of vaccination programs in this age group has been debated globally. Consequently, we estimated the effectiveness of the 3-dose series of BNT162b2 (Pfizer-BioNTech) in children aged 6 months to 4 years and the complete 2-dose series of CoronaVac (Sinovac) in children aged 3 to 4 in reducing the risk of hospitalizations due to COVID-19-attributed severe acute respiratory infection (SARI) in Brazil. MethodsWe conducted a retrospective cohort study in 24 Brazilian municipalities, using surveillance data. We evaluated vaccine effectiveness in reducing the incidence rate of COVID-19-attributed SARI hospitalizations from July 2023 to December 2024. Covariate adjustments, defined a priori based on a conceptual model represented by a directed acyclic graph (DAG), were implemented using random-effects Poisson regression models. We also analyzed alternative vaccination schedules and obtained age-specific estimates of effectiveness. ResultsThe cohort comprised 37.6 million person-months of follow-up and 1,384 COVID-19-attributed SARI hospitalizations, including 27 associated deaths. The 3-dose series of BNT162b2 vaccine had an effectiveness of 97% (IRR 0.03, 95%CI 0.01-0.10) in the group aged 6 months to 4 years, with no significant differences among age-specific estimates. No deaths occurred among children who completed the 3-dose series, whereas four deaths were observed among those with fewer doses. The effectiveness of CoronaVac was small and not statistically significant (IRR 0.96, 95%CI 0.57-1.62). However, no deaths were recorded among children who received any number of CoronaVac doses, and no COVID-19-attributed SARI hospitalizations were observed among those who received a third dose of this vaccine. ConclusionsThe 3-dose series of the mRNA vaccine (BNT162b2) had high and consistent effectiveness in protecting against severe COVID-19 in children aged 6 months to 4 years. These findings support the maintenance of routine COVID-19 vaccination in this age group.
Pantea, I.; Conlan, A. J. K.; Gaythorpe, K. A. M.
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Incidence of norovirus has strong seasonality in temperate and continental climates. Many studies have examined its association with climate variables, but evidence remains disparate. We address this gap by performing a systematic review to summarise and interpret the strength and directionality of associations between climate variables and norovirus incidence. Embase, Scopus, Web of Science and PubMed databases were screened for peer-reviewed studies on 2nd of December 2024. Articles were included if they described any climate or meteorological variable, in a categorical or numerical format, relative to a measurement of norovirus incidence risk in a human population, or prevalence or survivability outside the human host. Bias was assessed using a modified Critical Appraisal Skills Programme checklist. If dispersion of the effect in a human population was provided, the mean size was calculated using inverse variance weighting. The effect size outside the host was summarised as D-values, representing the time required to achieve a 90% reduction in the detected amount of virus. A total 139 studies were included. Predictors of risk were ambient and water temperature, relative and absolute humidity, anomalies of ambient temperature and precipitation, atmospheric and vapour pressure. High heterogeneity in direction and size of effects was observed due to regional differences in the factors driving norovirus seasonality and differences in outcome and exposure definitions. Our review suggests that the sensitivity of norovirus to individual climate variables is region and time specific, reflecting geographical differences in the relative importance of norovirus transmission via environmental pathways versus human-to-human contact. Plain Language SummaryNorovirus, a gastrointestinal virus, has a higher number of cases during specific months of the year. Regions with similar types of climate appear to have similar time periods when the increase in the number of infections occurs, which has been linked to norovirus case numbers being correlated to individual climate variables, such as temperature or rainfall. To understand how these associations compare globally and what are their potential explanations, we screened four major scientific databases, namely Embase, Scopus, Web of Science and PubMed. After the selection process, a total 139 peer-reviewed studies were included in this study. We found that ambient and water temperature, relative and absolute humidity, anomalies of ambient temperature and precipitation, atmospheric and vapour pressure were predictors of an increase in norovirus cases. However, the strength and direction of the relationships differed from region to region. A potential explanation is that geographies also differ in how important individual routes are for the transmission of norovirus, specifically via the environment as opposed to direct human-to-human contact, whereas climate is likely to have a greater influence on the former. Key pointsO_LIThe strength and direction of associations between climate variables and norovirus incidence varies by region and time period C_LIO_LIThe strength of associations vary across the transmission routes of norovirus, e.g., environmental versus human-to-human contact C_LIO_LIClimate variables impact norovirus survival and dissemination outside the host, which may inform models of environmental virus transmission C_LI
Biswas, R. S. R.; Moharar, T.; Karim, M. R.; Hasan, M. M.; Biswas, S. K.
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IntroductionDengue has been prevalent in a regular fashion in Bangladesh and Chattogram for the last 6-7 years and is showing some serotype twisting. So, the objectives of the present study were to explore the burden of dengue serotypes in Chattogram. MethodsIn this study, 223 Dengue RT-PCR positive patients were evaluated for serotyping. Gender and age group, along with cycle threshold (CT) values, were also collected. Data after collection were compiled, analyzed, and plotted in Microsoft Excel and GraphPad Prism 10.4. Ethical clearance was taken to conduct the study. ResultsAmong 223 patients analyzed, males and females were found near equal (113 and 110). Middle-aged patients were more than the extremes of age. The mean {+/-} SD of age was 33.55 {+/-} 13.67 years. Regarding serotype distributions, isolated Den 1, Den 2 and Den 3 were found 1.3%, 73.1% and 6.7%, respectively. Concurrent infections with multiple serotypes were observed in several patients, most notably the Den 2 and Den 3 combination, which accounted for 14.3% (n=32) of the cases. Other co-infections were less frequent: the Den 1 and Den 2 pairing appeared in 3.6% (n=8) of the cohort, while triple-serotype infections (Den 1, 2, and 3) and Den 3/Den 4 pairings were rare, each occurring in only 0.4% of patients. Statistical analysis of CT values revealed no significant sex-based differences for Den 2 and Den 3. However, significant variations in CT values were observed when comparing Den 1 against both Den 2 and Den 3 (p < 0.05). In contrast, the difference between Den 2 and Den 3 Ct values remained statistically insignificant. ConclusionIn the year 2025, Dengue serotypes 2 and 3 were found to be the most prevalent, both in isolated or in combinations and Den 1 and Den 4 were found minimum. Exposure to multiple serotypes and twisting from one serotype to another might influence the dengue outcome in future, which needs further exploration.
Garcia, M.-M.; Rodriguez, X.; Lopez, S. J.; Reyes Dorante, J. J.; Aldana, E. J.; Orduno, N. E.; Lugo, A.; Salazar, D.; Carvallo, N.; Rivas, Y.; Estofolete, C. F.; Nogueira, M. L.; Lezcano-Coba, C.; Galue, J.; Juarez, Y.; Donnelly, C. A.; Narciso Franco, J.; Carrera, J.-P.
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Background Venezuelan haemorrhagic fever (VHF), caused by Guanarito virus (GTOV), is a zoonotic disease endemic to the western plains of Venezuela. Despite decades of recognition, its epidemiology and clinical profile remain poorly characterised. Methodology We analysed individual level data from standardised case report forms submitted to the Venezuelan National Epidemiological Surveillance System between 2017 and 2024 for suspected VHF cases in Barinas, Apure, and Portuguesa. Demographic, clinical, and laboratory variables were examined to characterise temporal and geographical patterns and to define the clinical profile of VHF compared with endemic arboviral infections. Principal Findings Among 480 suspected cases, 72 (15.0%) were laboratory confirmed GTOV infections. Confirmed cases occurred predominantly in men engaged in agricultural or service related occupations, with the highest prevalence among individuals aged 46 to 90 years. A marked seasonal pattern was observed, with most cases occurring between September and January. The most frequently reported symptoms included headache, haemorrhage, sore throat, and diarrhoea. Compared with other endemic arboviral infections, GTOV was more strongly associated with headache, myalgia, sore throat, haemorrhage, and abdominal pain, delineating a distinct clinical phenotype relative to diseases caused by encephalitic alphaviruses, chikungunya virus, dengue virus, and Zika virus. The case fatality ratio among laboratory confirmed cases was 36.1% (95% CI: 25.1 to 48.3). GTOV infection was independently associated with mortality (adjusted relative risk [aRR] 3.66; 95% CI 2.28 to 5.87; p < 0.001), underscoring its substantial clinical severity. Conclusion GTOV remains endemically transmitted in western Venezuela, disproportionately affecting older men engaged in agricultural and service related occupations. Its seasonality and clinical phenotype, characterised by haemorrhage, sore throat, and gastrointestinal symptoms, highlight the need for clinical awareness and improved differential diagnosis, particularly in remote endemic settings with limited access to laboratory testing.
Cherkos, B.; Aderaw, Z.; Taye, D.; Handebo, S.
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BackgroundMeasles is a highly contagious infectious disease and a leading cause of childhood morbidity and mortality worldwide. In developing country like Ethiopia, effective immunization is a proven strategy for reducing measles related illness and deaths. However, measles second dose vaccination drop out has become a major public health concern. In a densely populated city such as Addis Ababa drop rate tends to be higher than the minimum acceptable threshold, leading to increased number of cases and recurrent outbreaks. Despite of this limited evidence exists on the determinants of second dose drop out and the problem is not well investigated, as a result this study will try to identify determinants of measles second dose vaccination dropout among children 24 - 35 months of age. ObjectivesTo identify determinants of measles second dose vaccination dropout among children 24 - 35 months of age Addis Ababa, Ethiopia in 2025. MethodCommunity based unmatched case control study was conducted in Addis Ababa from September 1/2024 to October /2025 with a total of 636 participants, consisting of 212 cases and 424 controls. Data were collected using structured Quesionariie and entered into EpiData 3.1 then StataSE 18 was used for detailed analysis including Descriptive statistics. Model fitness was checked using Hosmer-Lemeshow and multicollinearity were assessed using variance inflation factor. Furthermore, Bivariable and multivariable logistic regression analyses was employed and Adjusted odds ratio with 95% confidence intervals was used to identify significant variables. ResultsA total of 620 mothers/caregivers participants respond to the study, comprising 206 (97%) cases and 414(97.6%) controls, yielding a total response rate of 97.4%. In this study, waiting time longer than 30 minutes (AOR= 3.34, 95%CI: 1.86-5.9), Lack of counseling (AOR = 2.63, 95% CI: 1.60-4.30), Lack of reminders (AOR = 2.86, 95% CI: 1.89-4.30), Previous adverse event following immunization (AOR = 2.00, 95% CI: 1.39-3.00), postnatal care visit (AOR = 0.58, 95% CI: 0.40-0.85) and family size of greater than 3 (AOR = 1.96, 95% CI: 1.29-2.98) were significantly associated with measles second dose dropout. Conclusion and recommendationIn study shows measles second dose dropout is found to be associated with long waiting time, lack of counseling, lack of reminder, history of adverse event following immunization and postnatal visit. Which suggests Strengthening Immunization Counseling, reducing waiting time, establishing effective reminding system, integrating Immunization with postnatal services and promptly addressing concerns about adverse event following immunization can help reduce measles second dose dropout.