IJID Regions

Background/Aims: In medical practice, the rising prevalence of infections in kidney transplant recipients (KTRs) is a notable concern. However, understanding the incidence and risk factors associated with infections in KTRs remains limited. This study aims to assess the incidence and factors associated infection among KTRs. Additionally, we also investigate the median time of each infection among KTRs. Methods: A retrospective cohort study was conducted from 1 January 2018- 31 December 2022 at Thailand's tertiary hospital. We performed univariable and multivariable logistic regression analyses to identify potential risk factors related infection and investigated for the incidence and median time of each infection among KTRs. Results: A total of 179 participants were included in this study. Our findings reveal the kidney from living donor was protective factor for infection among KTRs (aOR 0.063, 95% CI 0.005-0.792; p = 0.032). Urinary tract infections (UTIs)showed as the predominant pathogenic manifestation among KTRs (43%). The median time of UTIs, cytomegalovirus (CMV) infection and pneumocystis pneumonia (PCP) were 16, 57 and 94.5 days, respectively. Conclusions: Our study establishes that receiving a kidney from a living donor is a protective factor against post-kidney transplant infections. Particularly urinary tract infections were most common of infection. Monitoring urinary tract infections post-transplantation is recommended. Moreover, awareness of UTI, CMV infection and PCP should be concerned during 2-3 months after transplantation. However, due to a small sample size; we recommend to increase the number of particular participants in further investigations.

Globally, Hepatitis C Virus (HCV) infection is a leading cause of chronic liver disease and remains a significant public health threat in Ghana. However, there is a paucity of data on the prevalence and awareness of HCV among market sellers and informal workers in Ghana. This study sought to determine the prevalence and awareness of HCV among this population. This was a cross-sectional study conducted among 397 sellers and workers at Kejetia market from December 2024 to January 2025. HCV was diagnosed using the One Test Hepatitis C Virus Test Strip (Qingdao Hightop) for the qualitative detection of HCV antibodies. Data were analysed using SPSS version 26 and GraphPad Prism version 8.0. A p < 0.05 was considered statistically significant for awareness of HCV. The prevalence of HCV in this study was 4 (1.0%). Awareness of HCV was low at 112 (28.2%). Residence (p=0.021) and age group (p=0.040) were significantly associated with HCV awareness. Age 41-50 years was almost three times more likely to be aware of Hepatitis C infection compared to [&le;] 30 years. Although the prevalence of HCV was low, awareness of the infection was also limited; this highlights the need for public health authorities to implement targeted HCV education programs in major markets to effectively reach informal sector workers who are often overlooked by conventional campaigns.

Background and Aims: Hepatitis B virus (HBV) infection remains a significant global public health concern, particularly in developing countries, where it poses a major challenge to safe blood transfusion services. Blood donors represent an important subset of the population for assessing HBV prevalence, as transfusions are a key route for transmission. This study aimed to determine the seroprevalence of HBV infection among blood donors at Methodist Hospital, Wenchi, Ghana. Methods: A retrospective analysis was conducted using data from the blood bank at Methodist Hospital, Wenchi from January 2022 to December 2023 and analyzed using SPSS version 25. Results: The overall HBV seroprevalence among blood donors was 6.8%, with a higher infection rate among females (16.7%) compared to males (6.3%). The highest seroprevalence (9.4%) occurred in donors aged 30 to 39 years and voluntary donors showed a higher infection rate (8.2%) than non-voluntary donors (6.5%). Among blood groups, individuals with blood groups A and B exhibited the highest infection rates (8.5%). Factors such as age (AOR: 2.62, 95% CI: 1.10 to 5.32, p-value =0.023), gender (AOR: 2.10, 95% CI: 1.05 to 4.35, p-value= 0.004) and Rhesus status (AOR: 1.68, 95% CI: 1.08 to 3.35, p-value= 0.031) were significantly associated with HBV infection. Conclusion: The study revealed a significant HBV seroprevalence of 6.8% among blood donors, classifying the region as medium-endemic per WHO guidelines. The findings underscore the urgent need for enhanced HBV screening, rigorous blood safety measures and targeted public health interventions including vaccination and education campaigns to mitigate the transmission risk. Keywords: Hepatitis B virus, Blood donors, Seroprevalence, Seropositive, Ghana

Purpose: Childhood immunisation witnessed reduced coverage and delays globally during the Covid19 pandemic. This study aimed to identify gaps in routine childhood immunisation in southern India and the effect of the pandemic in censused rural and tribal populations. Methods: This study was conducted between August and September 2021 in a hard-to-reach tribal block (Jawadhu Hills) and rural (Timiri) block in Tamil Nadu. The proportion of full immunisation coverage (FIC), age-appropriate coverage and vaccination delays were calculated in the pre-pandemic (prior to March 2020) and pandemic (lockdown) period. Results: Among 2746 children (aged <30 months, with immunisation cards available) surveyed in these populations, overall FIC among children between 12-23 months of age was 50.8% (95%CI: 46.6-55.0) in Jawadhu and 83.7%; (81.1-86.2) in Timiri. In Jawadhu, coverage of oral polio vaccine3 (OPV3) decreased from 78.3% (73.4-82.6) pre-pandemic to 70.0% (66.6-73.2) during the pandemic; inactivated polio vaccine2 (IPV2) from 76.9% (72.1-81.2) to 69.1% (65.5-72.4); Pentavalent3 from 78.0% (73.1-82.4) to 70.2% (66.8-73.5); and Measles containing vaccine1 (MCV1) from 74.6% (67.6-80.8) to 56.7% (53.3-60.1). In Timiri, only MCV1 coverage decreased from 92.9% (88.7-95.9) to 85.4% (83.3-87.3). Factors associated with not receiving MCV1 included due date of vaccination falling during the pandemic lock downs, higher birth order, younger and less educated parents, and residing in the tribal block. Conclusion: This study highlighted differences in routine childhood immunisation vaccine coverage and impact of the pandemic in a geographically remote tribal block in contrast to a more accessible, rural block. Resilient health systems are essential to ensure sustainability in gains in vaccination coverage, especially in remote areas, and should be part of pandemic preparedness.

ABSTRACT Background: Coronavirus disease 2019 (COVID19), caused by severe acute respiratory syndrome coronavirus 2, spreads rapidly and can cause severe acute respiratory failure; advanced age, chronic disease, and other comorbidities increase the risk of severe infection. By early 2022, more than 477 million cases and 6.11 million deaths had been reported globally. This study assessed the association between ABO blood group and severity of COVID-19 pneumonia among patients admitted to Eka Kotebe General Hospital, Addis Ababa, Ethiopia. Methods: A hospital-based cross-sectional study was conducted using systematic random sampling; data were abstracted from patient records, and severity was modeled using ordinal logistic regression, with multicollinearity and the proportional odds assumption checked via the variance inflation factor and test of parallel lines, and model fit assessed by likelihood ratio chi-square and goodness of fit tests. Results: Of 355 patients included (100% response rate), 54.9% were male and 31.0% were older than 61 years (median age, 48 years; interquartile range, 33-65). Overall, 10.14% were asymptomatic, 24.79% had mild/moderate disease, 60.56% had severe disease, and 4.51% had critical disease. Pregnancy and presence of complications were significantly associated with severity (adjusted odds ratio, 0.15 [95% CI, 0.04-0.57] and 14.96 [95% CI, 4.14-54.01], respectively); ABO blood group showed no association with severity. Conclusion: These findings demonstrate a substantial association between COVID-19 severity and complications and pregnancy, but not ABO blood group.

Background: Hepatitis E virus (HEV) is highly endemic in several African countries with high mortality rate among pregnant women. The prevalence of HEV in Niger among pregnant women is unknown. We hereby aim to report the prevalence and risk factors of HEV among pregnant women in Niamey, Niger. Methods: Blood samples were collected from pregnant women attending antenatal consultation in three selected Health centers in Niamey. Data were collected for socio demographic characteristics using a structured questionnaire. Samples were tested using ELISA and qRT-PCR for anti- HEV IgM and RNA detection respectively. HEV associated risk factors were determined using multivariate logistic regression models. Results: A total of 491 pregnant women were enrolled with mean age of 26.5 years. The prevalence of anti-HEV IgM antibodies was 17.1%, while HEV RNA was detected in 3.46% of participants, indicating recent and active HEV infection. Anti-HEV IgM seropositivity was more frequent among women aged 26-30 years and those in the third trimester of pregnancy. Gravidity was significantly associated with HEV RNA positivity (p = 0.032). In multivariable analysis, the use of well water was independently associated with HEV infection (aOR = 75.70; 95% CI: 1.23-4643.20; p = 0.039). Conclusion: In view of the high seroprevalence of HEV among pregnant women, preventive measures including hygiene sensitization should be prioritized. Further studies should be conducted to assess the real impact of HEV infection on maternal and fetal health.

Abstract Background: Rising global temperatures are intensifying exposure to extreme heat, yet access to air conditioning (AC) remains unequal which leaves vulnerable populations without protection against the heat. Household survey data on AC ownership is scarce in low- and middle-income countries limiting the ability to identify areas of cooling gaps. Methods: In this study, we develop a geospatial machine learning framework that integrates household data from the Demographic and Health Surveys (DHS) program with high resolution climatic, socioeconomic and demographic covariates to generate a 5km resolution prediction of AC ownership across low- and middle-income countries in Africa and Asia for the year 2023. Results: The resulting map reveals strong spatial inequalities with high predicted prevalence in wealthier and urban regions, and near zero prevalence across much of Central and West Africa and rural areas. These patterns reflect the adaptation cooling gap where those most exposed to extreme heat are least able to adapt through access to cooling. Conclusion: By producing the first continental-scale, high resolution map of AC ownership, this study lays the foundation for designing and targeting equitable cooling strategies, support heat-health planning particularly in communities most affected and informing sustainable energy policy.

Background: ALECT2 is the third most common cause of renal amyloidosis in the United States, with a strong predilection for Hispanic patients in the Southwest. (PMID:24522497) Despite its regional prevalence, the data on the trajectory of kidney function decline and post-transplant outcomes remain poorly characterized. Methods: This is a retrospective study of patients diagnosed with ALECT2 by kidney biopsy at UNM from January 2014 to April 2024. Pre- and post-biopsy eGFR trajectories and post-transplant allograft function were analyzed. Results: 12 patients had pre-biopsy data available, with the mean age at diagnosis 64 SD 12.0 years, 8(67%) were females, and 8 identified as Hispanic. Mean eGFR at diagnosis was 31 (SD 29) indicating advanced kidney disease with 67% diagnosed as CKD stage 4 or 5. Concomitant kidney pathology was identified in 50% with diabetic nephropathy being present in 2/3 of those. A significant change in the eGFR trajectory identified at the time of biopsy through change point analysis [Figures A,C,D] Among four patients who underwent kidney transplantation, allograft eGFR remained stable over more than 60 months of follow-up [Figure D] Conclusion: In this cohort of predominantly Hispanic patients, ALECT2 amyloidosis presented with advanced CKD and accelerated loss of kidney function, which prompted a biopsy that detected the disease. Post- transplant allograft function was well maintained, supporting kidney transplantation as a viable treatment strategy for ALECT2-associated kidney disease.

Respiratory infections remain a relevant global health concern nowadays. The rapid dissemination and high mutational ratio of some pathogens, amid human demographic drivers, increases their pandemic potential. On the other hand, some bacterial infections have re-emerged with new resistant variants, supporting the need of updated or more potent vaccines. The development of nasal vaccines, with the capacity to efficiently induce immune response at the respiratory tract and systemic compartments, constitutes an appealing strategy to tackle respiratory infections, including tuberculosis. In this work, two synthetic compounds, the ODN-39M and the peptide LALF32-51, are evaluated as nasal vaccine adjuvants for the Ag85B antigen from Mycobacterium tuberculosis. The capacity of such adjuvants to enhance the immune response at systemic and mucosal compartments following intranasal immunization was assessed in Balb/C mice. The ODN-39M was able to potentiate the immune response, showing preferentially a Th1 pattern. The vaccine preparation containing this CpG adjuvant plus Ag85B induces potent cell-mediated and high IgA specific antibody response in lungs, along with systemic immunity. A preliminary study of the interaction between the ODN-39M with the NALT immune cells shows the early recruitment of lymphoid cells, and the increase of CD69 activation marker, mainly in B and dendritic cells. Although further studies should be done to reach a deeper understanding of NALT functioning, including the development of local innate response, the current data enrich the scarce reports focused on this compartment and support the use of the ODN-39M as a potent and potentially safe adjuvant option for future nasal vaccines.

Background Non-alcoholic fatty liver disease (NAFLD) has become a common metabolic disorder in paediatric age groups and is a major contributor to the burden of health economics. However, there is a lack of comprehensive data on the prevalence of this condition among children. Methods English language literature published from inception until April 2025 was searched from the electronic databases, i.e., PubMed/Medline, Scopus, Embase, and CINAHL. Original data published in any form that reported NAFLD prevalence among children and/or adolescents in India were included. The subgroup analysis of prevalence was done based on the risk category, i.e., average risk group and high risk group (obesity or overweight, metabolic syndrome, etc.). The prevalence estimates were pooled using the random-effects model. Results A total of 11 studies (six in high-risk populations and 5 in the average-risk general population) comprising data from 3512 individuals were found eligible and were included. The overall pooled estimate of NAFLD prevalence among the children and adolescents was 35.4% (95% CI: 19.7% to 52.9%) with very high heterogeneity(I2=99.0%). The pooled prevalence of NAFLD among average/low risk children and adolescents was 10.7% (95%CI: 5.2% to 20.5%) with high heterogeneity across the studies (I2= 96.6%, p=0.001) whereas the pooled prevalence of NAFLD in high risk overweight/obese children and adolescents was found to be 59.7% (95% CI:55.2% to 64.1%) with moderate heterogeneity across the studies (I2=50.90%; H2=2.04; Q (5) = 10.03; p=0.07) Conclusion This systematic review demonstrates that non-alcoholic fatty liver disease (NAFLD) poses a growing health concern among Indian children and adolescents, as 1 out of 3 children/adolescents is suffering from it, with a disproportionately high burden observed in those who are overweight or obese.

Introduction Hepatitis E virus (HEV) in pregnancy is associated with high maternal and perinatal morbidity and mortality. The safety and efficacy of the recombinant protein HEV vaccine (HEV239, Hecolin) have been established in non-pregnant adult populations but there is limited information among pregnant women. This trial has two co-primary objectives: 1) to assess pregnancy-related and/or serious safety events among pregnant women between 14 and 34 weeks of gestation receiving two Hecolin doses four weeks apart compared to placebo recipients, and 2) to determine immune non-inferiority of pregnant recipients of two Hecolin doses four weeks apart compared to non-pregnant women. Methods and Analysis This is a multi-site, randomized, observer-blinded, placebo-controlled vaccine safety and immunogenicity trial in pregnant women and non-pregnant women of reproductive age in Karachi, Pakistan. A total of 2,358 healthy women will be enrolled, including 2,208 pregnant women between 14 and 34 weeks of gestation, who will be randomized in a 1:1 ratio (stratified by gestational age, 14-27 and 28-34 weeks) to receive either Hecolin or a normal saline placebo in two doses administered 1 month apart during pregnancy and a third dose administered postpartum, approximately 5 months after the second dose. A third arm of 150 non-pregnant women aged 16-45 years will receive Hecolin on 0, 1, and 6 months. The co-primary outcomes will be (i) the proportion of pregnancy-related AESIs and SAEs in pregnant participants from the first dose until the end of study follow-up, compared with placebo, and (ii) the geometric mean concentration (GMC) of anti-HEV IgG at four weeks after the second dose, comparing pregnant vaccine recipients with non-pregnant vaccine recipients (non-inferiority margin of 0.67 for the GMC ratio). Immunogenicity will be evaluated in a pre-specified subset of 300 participants receiving Hecolin, including 150 pregnant participants and 150 non-pregnant participants. Secondary outcomes will include maternal, neonatal, and infant safety outcomes, as well as immunogenicity according to the number of Hecolin doses received and the trimester of vaccination. Ethics and Dissemination The trial was approved by the National Bioethics Committee (NBC) of Pakistan (Reference number: 4-87/NBC-910), the institutional Ethics Review Committee (ERC) of the Aga Khan University (Reference number: 8298), and the Institutional Review Board (IRB) of the International Vaccine Institute (IVI) (Reference number: 2022-007). All participants will provide written informed consent in accordance with Good Clinical Practice. The results will be submitted to World Health Organization (WHO) Strategic Advisory Group of Experts in Immunization (SAGE), and disseminated through conference presentations, and peer-reviewed publications.

Hydroclimate whiplash, defined as the rapid transition between unusually wet and dry conditions, is expected to intensify under climate change, yet its population health impacts remain largely unknown. Here we quantified the association between hydroclimate whiplash and mortality across the contiguous United States from 2003 to 2023 using monthly county-level mortality records, standardized precipitation evapotranspiration index data, and two-stage time-series models. We identified overall and direction-specific dry-to-wet and wet-to-dry whiplash events at seasonal and sub-annual timescales and across 5-, 10-, and 20-year recurrence intervals. More severe whiplash events were associated with higher all-cause mortality risk; 5-, 10-, and 20-year sub-annual overall whiplash events increased mortality risk over five months by 3.4%, 4.5%, and 5.7%, respectively. Elevated risks were observed across cause-specific mortality outcomes, with the strongest association for infectious diseases. We estimated that 103,471 deaths were attributable to overall whiplash during the study period. These findings identify hydroclimate whiplash as an emerging climate-related public health threat and suggest that adaptation strategies focused on single hazards may underestimate the health burden of rapid, sequential hydroclimatic extremes.

There is currently no clinical data for the effectiveness of the only licensed Ebola virus disease vaccine (Ervebo) against Bundibugyo virus disease. A number of studies have shown immune cross-reactivity with Bundibugyo virus after Ervebo vaccination. However, antibody recognition of Bundibugyo is around 2.8-fold lower than recognition of Ebola virus. Here, we aimed to infer how a 2.8-fold drop in immune recognition may affect Ervebo protection against Bundibugyo virus disease based on analysis of data on Ervebo immunogenicity and protection from Ebola virus disease. This work has three main components. Firstly, we analysed the timing of vaccine protection in the Ervebo pivotal ring vaccination clinical trial. Secondly, we performed a systematic review and meta-analysis of antibody responses to Ebola virus after Ervebo vaccination over time. Thirdly, we combined these data with previously reported data on the cross-reactivity to Bundibugyo virus to infer protection of Ervebo against Bundibugyo virus disease. We find that the clinical trial data for Ervebo supports vaccine protection beginning earlier than 10 days after vaccination. Secondly, binding antibody levels against Ebola virus on day 28 post vaccination (peak responses) were on average 12.9-fold (95% confidence interval, CI: 6.4 - 26.0) higher than on day 7, 6.3-fold (95% CI: 3.7 -10.8) higher than on day 10, and 2.5-fold (95% CI: 1.4 - 4.4) higher than on day 14 (neutralising antibodies showed similar results). Finally, we consider the scenarios where antibody levels to Ebola virus at day 7 or 10 are putative protective thresholds against Ebola virus disease, and we assume these thresholds also apply for Bundibugyo virus disease. Then, with a 2.8-fold reduction of responses to Bundibugyo compared to Ebola virus, we predict antibody responses to Bundibugyo virus after Ervebo vaccination are likely above these putative protective thresholds.

Background In adults, cold-attributable mortality exceeds heat-attributable mortality roughly 17-fold. Child-specific evidence has begun to emerge only recently - a nationwide Brazilian case-crossover study located the minimum mortality temperature (MMT) for under-five deaths, and a 56-country survey-based analysis linked monthly temperature anomalies to under-five mortality - but no multi-country, climate-zone-resolved estimate of the childhood respiratory-infection MMT exists, and whether temperature variability is independently associated with childhood respiratory mortality at the global scale is unknown. We quantified both. Methods We combined Global Burden of Disease 2023 mortality estimates, lower respiratory infection (LRI) deaths at ages 0-19 years and asthma deaths at ages 0-24 years, 171 countries, 1990-2023 - with 0.5 deg monthly land temperature and diurnal temperature range (DTR) fields from C-LSAT/C-LDTR (1901-2023). Four exposure dimensions (annual mean, DTR, seasonal amplitude, interannual variability) entered two-way fixed-effects models with Driscoll-Kraay standard errors. A quadratic term in mean temperature located the MMT, with percentile confidence intervals from a 300-replication country-cluster bootstrap. Future-exposure leads, country-level detrending, and permutation tests assessed contemporaneous causality, applied to both the linear coefficients and the quadratic term generating the MMT; national pneumococcal conjugate vaccine (PCV3) coverage and ambient PM2.5 exposure series were added as time-varying mechanistic covariates. Results The childhood LRI MMT was 17.1 C (95% CI 14.7-19.8), the 36th percentile of the annual-temperature distribution; zone estimates were 24.7 C in tropical and 15.8 C in subtropical countries, with weak temperate and no subarctic identification. The quadratic term underpinning the MMT, however, failed both falsification checks - future temperatures reproduced the U-shape and country-level detrending erased it - so these MMT values describe a trend-level geographic pattern of the annual construct rather than a contemporaneous dose-response. Interannual temperature variability was positively associated with LRI (+0.278, 95% CI 0.102-0.454; p = 0.002) and asthma mortality (+0.836, 95% CI 0.447-1.226; p = 2.6 x 10^-5) per 1 C, but future-exposure models returned nearly identical significant coefficients and detrending erased significance, supporting only a trend-level association; adjustment for national PCV3 coverage and PM2.5 exposure left these estimates essentially unchanged. Annual mean temperature was likewise inversely associated with both outcomes at the trend level; DTR and seasonal amplitude showed no independent within-country effects. Conclusions This study provides the first multi-country, climate-zone-resolved geography of the optimal temperature for childhood respiratory survival, spanning 171 countries; because the underlying quadratic association is trend-level, the estimates are directional. The observed variability-mortality associations are trend-level signals rather than contemporaneous causal evidence; daily-scale, child-specific designs are required to determine whether short-term thermal variability affects paediatric respiratory mortality.

Background Childhood respiratory mortality in China has fallen by over 90% in three decades alongside sustained national warming, yet national long-run evidence on temperature and child respiratory mortality is lacking. Methods We linked Global Burden of Disease (GBD) 2021 mortality estimates for China - lower respiratory infections (LRI), ages 0-19, and asthma, ages 0-24, 1990-2021 - with C-LSAT 0.5 deg gridded temperature data (1990-2019), aggregated nationally and to five climate zones. Four annual indicators (mean temperature, diurnal temperature range, seasonal amplitude, interannual variability) entered regressions of log mortality rates with Newey-West standard errors. A bootstrapped (500 resamples) quadratic model probed the minimum mortality temperature (MMT), with PM2.5-adjusted analyses and future-exposure, permutation, and detrended falsification tests. Results LRI deaths fell by 96.3% (330,194 in 1990 to 12,098 in 2021; 95% uncertainty interval 9,669-14,891) and asthma deaths by 94.9% (3,287 to 167), while mean temperature rose 0.364 deg C per decade and diurnal temperature range narrowed 0.092 deg C per decade. Baseline coefficients were large (mean temperature -1.696, SE 0.174; diurnal temperature range +2.408, SE 0.336; seasonal amplitude -0.162, SE 0.082; interannual variability +2.924, SE 1.514, per 1 deg C in log rate), but the future-exposure test failed and detrending nullified every coefficient: the associations are trend-level, and short-cycle causal effects are not identifiable. Nor was the national MMT identifiable - observed temperature support spans only 6.66-8.13 deg C, and the nominal turning point of 35.84 deg C is an extrapolation artifact (quadratic term p = 0.963). Within the observed range, warming and declining mortality moved in the same direction. Conclusions The 96% decline in childhood respiratory mortality cannot be attributed to warming. China sits on the low-temperature side of the optimum, and the marginal direction of future warming requires stronger designs to establish. The falsification framework offers a discipline for climate-health inference in China.

Coccidioidomycosis (Valley fever) is a soilborne mycosis endemic to the US Southwest whose incidence has increased markedly in recent decades. Environmental conditions are thought to influence the soil-dwelling lifecycle of Coccidioides; however, most prior studies have relied on above-ground meteorological conditions - primarily precipitation and air temperature (AT) - with few examining subsurface soil moisture (SM) and soil temperature (ST), which may more directly influence the fungal lifecycle. No study of coccidioidomycosis, or any other environment-sensitive soilborne mycosis, has examined how deeper-layer soil conditions relate to disease incidence, despite the prevailing soil-sterilisation hypothesis implicating deeper soil as a potential fungal refugium. Furthermore, nonlinear exposure-lag-response relationships for key dust-dispersion exposures - including PM10, a potential proxy for airborne spore concentration, and wind speed - remain uncharacterised. We aimed to estimate and compare the associations between coccidioidomycosis incidence and environmental exposures across multiple above- and below-ground layers, and to evaluate their independent and combined predictive performance. This ecological time-series study analysed 185,486 reported cases of coccidioidomycosis in Arizona's hyperendemic tri-county region (Maricopa, Pima, and Pinal) during 1997-2024. We developed a mechanism-informed multilayer environmental framework comprising one dust-dispersion layer (PM10, wind speed) and four soil-climate layers - meteorological (precipitation, AT), topsoil (0-10 cm), midsoil (10-40 cm), and deepsoil (40-100 cm) SM and ST. We fitted distributed lag non-linear models (DLNMs) with season-specific interaction terms to estimate exposure-lag-response associations between each environmental layer and coccidioidomycosis incidence. We then developed a two-stage stacked ensemble machine learning framework to assess each layer's independent predictive performance (stage 1) and integrate them into a unified forecast (stage 2), which was evaluated using a strictly held-out test period. At concurrent lags (1-3 months prior to reporting), coccidioidomycosis incidence was primarily associated with dustier, windier, and drier conditions, cooler air temperatures, and warmer topsoil. For each IQR increase, PM10 showed the most consistent concurrent associations, with significant positive incidence rate ratios (IRRs) across all four incidence seasons at lags 1-2 (ranging from 1.04 [95% CI 1.00-1.08] to 1.37 [1.26-1.48]). Across lags 1-36 months, all four soil-climate layers exhibited nonlinear, non-monotonic, and season-dependent associations with coccidioidomycosis incidence, characterised by alternating wet-dry and cool-warm oscillations. Topsoil displayed the most frequent significant associations, with moisture-temperature signals attenuating progressively from topsoil through midsoil to deepsoil. A depth-dependent lag structure was observed for both moisture and temperature, in which significant positive IRRs emerged at progressively shorter lags with increasing soil depth, accompanied by vertical divergence across depths at the same lag windows. For example, for fall incidence, positive moisture IRRs appeared at precipitation lag 15 (1.10 [1.00-1.21]), topsoil SM lag 9 (1.22 [1.15-1.30]), midsoil SM lags 8-9 (up to 1.23 [1.11-1.37]), and deepsoil SM lags 4-5 (up to 1.08 [1.01-1.16]); at these same lags, deepsoil SM was positively associated with incidence whereas topsoil SM and precipitation remained negatively associated. During the held-out test period (2021-2024), the multilayer ensemble generally captured seasonal and interannual variation well, including the timing and approximate magnitude of most peaks, outperforming all single-layer models. Although individual layers had slightly lower test RMSEs, their test gap ratios were substantially higher (0.27-0.67 vs 0.00), indicating that the ensemble generalised far more reliably. All five environmental layers contributed to the final ensemble forecast; the dust-dispersion and topsoil layers received the highest importance, with PM10 ranked as the most important predictor group. The best-performing of four pipeline configurations relied solely on environmental inputs available within one week, enabling the model to function as a near-real-time nowcast. This study provides the first evidence linking multilayer environmental exposures to coccidioidomycosis incidence across both temporal and vertical dimensions, offering new quantitative support for the prevailing soil-sterilisation and grow-and-blow hypotheses and demonstrating that a multilayer framework could improve both mechanistic understanding and predictive performance. The framework could be generalised to other endemic settings and readily extended with new data and methods to inform surveillance and public health preparedness. These findings support incorporating multilayer lagged environmental exposures into both effect estimation and forecasting systems to better prepare endemic regions for anticipated warming, drying, and increasingly variable climatic conditions.

Background Italy experiences a substantial heat-related mortality burden, but evidence on cause-specific mortality across its heterogeneous climatic settings remains limited. We aimed to quantify cause-specific mortality attributable to summer heat in Italy at national and ecological region levels and to map its distribution across municipalities. Methods We analysed daily deaths classified by underlying cause in eight ICD-10 groups among individuals aged 18-64 years and 65 years or older across 7,864 municipalities during June-August, 2004-2023. Mortality data were linked to area-weighted ERA5-Land daily maximum temperature. Nonlinear temperature-mortality associations were estimated with Bayesian hierarchical Poisson models, fitted separately for each cause, age group, and ecological region, with municipality-level attributable fractions. Findings High temperatures were associated with mortality from a broad range of causes, particularly among individuals aged 65 years or older. Among the study population, heat-attributable fractions were highest for nervous system diseases (14.93%, 95% credible interval 14.22-15.69) and mental and behavioural disorders (14.47%, 13.55-15.39). Circulatory diseases accounted for the largest absolute burden, with 85,524 heat-attributable deaths (82,762-88,271) across the summers of the 20 years considered. Interpretation The mortality burden associated with summer heat in Italy extended well beyond circulatory and respiratory diseases, highlighting the relevance of a broader range of health outcomes. These findings support heat-health strategies that account for cause-specific and geographical differences in heat-related risk, with greater consideration of neurological and mental health outcomes alongside established cardiorespiratory risks. Funding NextGenerationEU (CUP: B53C23002660006); Imperial College Research Fellowship; NIHR Imperial Biomedical Research Center (BRC: NIHR203323).

Background: Dengue virus (DENV) and Chikungunya virus (CHIKV) are important mosquito-borne arboviruses with expanding global distributions. Although recurrent outbreaks have occurred in the Horn of Africa since the early 2000s, their epidemiology and burden remain poorly characterized. This systematic review and meta-analysis estimated the prevalence of DENV and CHIKV, their distribution by country, diagnostic methods, circulating DENV serotypes, and mosquito vectors. Methods: Following PRISMA guidelines, PubMed, Web of Science, Scopus, SpringerLink, Nature Portfolio, and Google Scholar were searched for studies published up to October 2025. Eligible studies reported DENV and/or CHIKV infections in humans or mosquitoes in Kenya, Ethiopia, or Somalia. Random-effects meta-analyses were performed, with subgroup analyses by country, population, setting, and diagnostic method. Results: Of 3,351 records, 65 studies met the inclusion criteria, most from Kenya (63.1%), followed by Ethiopia (30.8%) and Somalia (6.1%). Pooled DENV prevalence was 20% for IgG, 10% for IgM, 6% for NS1, and 4% by PCR. Corresponding CHIKV prevalence was 5% for IgG, 8% for IgM, and 4% by PCR. Significant differences between countries were observed for DENV NS1 (p<0.0001) and PCR-confirmed infections (p=0.01). DENV prevalence was highest in the general population (16%) compared with febrile patients (6%) and mosquito vectors (1%) (p=0.033), whereas CHIKV prevalence was highest in rural settings (15%) (p=0.0002). All four DENV serotypes circulated in Kenya and Ethiopia, while DENV-2 and DENV-3 were reported in Somalia. Aedes aegypti was the predominant vector, reported in 92.3% of vector studies. Conclusions: DENV and CHIKV are important and likely underrecognized arboviral threats to global public health and in the Horn of Africa, with evidence of ongoing transmission and widespread exposure. Strengthened surveillance, diagnostic capacity, vector control, and regional collaboration are needed to mitigate their growing public health impact.

Background: Meningitis remains a major cause of global morbidity and mortality. We aimed to quantify the association between vaccine introduction and meningitis-related disability-adjusted life year (DALY) rates globally and across high-burden regions from 2000 to 2023. Methods: We conducted a longitudinal panel study of 188 countries using health metrics from the Global Burden of Disease study and WHO vaccine data. We estimated associations using two-way fixed effects regression models, adjusting for GDP and healthcare access. Analyses were stratified by baseline burden and included the African meningitis belt. Findings: Globally, meningitis DALY rates declined by 4.97% per year (p<0.0001). Introduction of the Hib vaccine was associated with a 6.7% reduction in DALY rates, and PCV with a 4.8% reduction. In high-burden countries, both vaccines were associated with larger reductions (~10%), while no significant effects were detected in low-burden settings. In the African meningitis belt, PCV introduction was associated with a substantial 16.8% reduction in DALY rates (p<0.0001). No significant global association was observed for meningococcal vaccines. Interpretation: Global declines in meningitis burden are strongly associated with Hib and PCV scale-up, with the greatest benefits in high-burden settings. These findings support prioritized vaccine deployment in endemic regions to maximize public health impact. However, the presence of pre-treatment trends for Hib suggests these estimates represent vaccine-associated population-level changes rather than strictly causal effects.

Background Hepatitis B virus (HBV) is a global health concern and the leading cause of chronic liver disease, including liver cirrhosis and hepatocellular carcinoma. The Uganda Ministry of health recommends screening of HBV for all pregnant mothers during antenatal care (ANC). However, limited literature exists regarding couple testing and outcomes, particularly in Northern Uganda. Objective We determined HBV seroprevalence and associated factors among pregnant women and their partner attending ANC clinic of Gulu Regional Referral hospital (GRRH), Gulu, Uganda. Methods Between 1st December 2023 and 28th February 2024, a hospital-based, cross-sectional study was conducted among eligible pregnant women and their male partners attending ANC of GRRH, Gulu, Uganda. Following systematic random sampling, pretested questionnaire was administered by an interviewer. Blood samples were collected for HBV surface antigen (HBsAg) rapid test, which was performed according to manufacturers instructions. Qualitative data was analysed using logistic regression in STATA version 15 SE. P<0.05 was considered statistically significant. Results A total of 242 couple pairs were enrolled. Overall, 8.3% (n=40) participants were seropositive for HBsAg; Male partners [M] (10.7%, n=26) and pregnant women [F] (5.8%, n=14). Sero-concordance (M negative [-ve] and F [-ve]; 83.5%, n=202), (M positive [+ve] and F [+ve]; 4.1%, n=10) and sero-discordance (M +ve and F -ve; 8.7%, n=21), (M -ve and F +ve; 3.7%, n=9). Factors associated with positive HBsAg were, being male (adjusted odds ratio [aOR]: 2.45, 95% Confidence Interval [CI], 1.15 - 5.21, p=0.02), daily alcohol consumption (aOR: 4.73, 95% CI: 1.40 -16.04, p=0.01), and no prior vaccination against HBV (aOR: 12.01, 95% CI: 4.07 - 35.65, p<0.001). Conclusion There is a high HBsAg seropositivity rate, particularly among male partners of pregnant women. There is an urgent need to have couples who come for ANC to be screened for HBV and to strengthen and sensitise young people for premarital HBV screening.