EPIDEMIOLOGY AND INFECTION

Trends in asthma exacerbations in children before, during and after the COVID-19 pandemic
Stadhouders L, Hoogteijling E, Duijts L and Lebon A
Editorial for epidemiology and infection, special issue on post-COVID condition
Saydah S
Adherence to oral zinc supplementation in the management of acute diarrhoeal disease among under-5 children: A systematic review and meta-analysis
Pradhan SK, Pati S, Sethy P, Dhusiya HR, Panda A, Pandit D, Kshatri JS, Kanungo S and Pati S
Zinc supplementation is a critical adjunct therapy for managing acute childhood diarrhoea, particularly in low-income countries (LICs) and lower middle-income countries (LMICs). However, adherence to the recommended zinc regimen remains a major challenge, limiting its effectiveness in real-world settings. This systematic review and meta-analysis aimed to estimate the pooled adherence rates to zinc supplementation for diarrhoea in children under 5 and identify key determinants of adherence. A comprehensive search of PubMed, Embase, Scopus, Google Scholar, ProQuest, and CINAHL was conducted between 2000 and 2024. A total of 10 observational studies were included, with pooled adherence of 63.45% (95% CI: 51.62-75.28) for 10 days regimen and 34.58% (95% CI: 7.08-62.09) for 14 days regimen, along with high heterogeneity. Sensitivity analysis confirmed robustness of these estimates. Key factors associated with adherence included caregiver education, provider counselling, medication acceptability, and economic constraints related to caregiver buying capacity. Doi plot asymmetry suggested possible publication bias for 10 and 14 days regimen. Overall, adherence to zinc therapy remains sub-optimal, particularly for 14 days regimen compared to 10 days regimen. Targeted interventions addressing behavioural, provider, and formulation related barriers are urgently needed to optimize zinc adherence and improve diarrhoea outcomes globally.
Risk factors associated with Candidemia: A single-centre retrospective case-control study
Kaya A, Eser F, Hasanoglu I, Kayaaslan B, Bozkurt A, Tezer Tekce AY, Dinc B, Kirca F and Guner HR
has emerged as a major nosocomial pathogen due to multidrug resistance (MDR), outbreak potential, and high mortality in critically ill patients. Identifying risk factors for candidemia is essential for prevention and infection control. In this single-centre, retrospective case-control study, we analysed adults with candidemia (n = 52) and matched controls (n = 104) hospitalized between February 2019 and October 2024. Matching was based on hospital unit and blood culture timing. Clinical and epidemiological variables were compared, and multivariate logistic regression identified independent risk factors. Antifungal susceptibility and 14- and 28-day all-cause mortality were evaluated as secondary outcomes. Independent risk factors included recent hospitalization (odds ratio (OR): 7.93), prolonged hospital stay (OR: 1.01), prior broad-spectrum antibiotic use (OR: 46.20), central venous catheter (CVC) (OR: 3.88), sepsis (OR: 9.43), and high Candida Colonization Index (OR: 14.10). All-cause mortality at 14 and 28 days was 30.8% and 46.2%, respectively. Fluconazole resistance was 96%, while 8.7% of isolates were pandrug resistant. candidemia represents a serious clinical challenge with substantial mortality and modifiable risk factors. Strengthening antimicrobial stewardship, colonization surveillance, and early recognition in high-risk patients may reduce its impact.
Spatio-temporal clustering and meteorological factors influencing HFRS incidence in mainland China, 2004-2021
Jiang H, Wu L, Wei J and Rao H
In this study, HFRS data were obtained from China CDC and ECDC, while monthly meteorological data and GDP were extracted from the National Bureau of Statistics of China website. Descriptive epidemiology, time series decomposition, and spatial autocorrelation analyses were employed to evaluate HFRS incidence patterns. A spatial panel data model was used to estimate the effects of meteorological and socio-economic variables on HFRS incidence. The average annual incidence rate of HFRS was 0.90/100000 in China, compared to 29.3/100000 in Finland. The incidence level in China was comparable to that in Belgium and the EU/EEA (excluding the UK), the high-incidence age group was 45-64 years, which was similar to Finland and the EU/EEA. HFRS in China exhibited marked seasonality. Three north-eastern provinces, Shaanxi, Shandong, and Jiangxi reported higher incidence rates. After adjusting for spatial individual effects and spatial autocorrelation, HFRS incidence was negatively associated with precipitation during the same period, per capita GDP showed no significant effect on HFRS incidence. Continued surveillance and prevention of HFRS remain necessary in China, particularly in Shaanxi. Additional disease prevention and control efforts should be directed towards individuals aged 45-64 years during the high-risk period from October to December.
Modeling the Influences of Climate Conditions on Measles Transmission in China - ERRATUM
Wang P, Chen J, Zhang W, Wang Y and Yang W
Waning in influenza vaccine effectiveness against influenza A(H1N1)pdm09-associated hospitalization in children in 2012/13
Chua H, Tsang TKL, Lee SL, Chan ELY, Kwan MYW, Wong JSC, Peiris M, Sullivan SG and Cowling BJ
Risk factors for Coagulase-negative Staphylococcal Surgical Site Infections
Nguyen C, Brown A, Lew A, Pettit N and Baccile R
Evaluating Google Trends as a Proxy for Symptom Incidence: Insights from the Winter COVID Infection Study in England 2023/24
Asplin P, Fyles M, Kennedy J, Ward T and Mellor J
Increased detection of Shiga toxin-producing (STEC) O26: Environmental exposures and clinical outcomes, England, 2014-2023
Findlater L, Quinn O, Douglas A, Sawyer C, Hall VJ, Jenkins C and Balasegaram S
In England, Shiga toxin-producing (STEC) serogroup O26 has recently emerged as a public health concern, despite fewer than half of diagnostic laboratories in England having the capability to detect non-O157 STEC. STEC O26 cases frequently report exposure to farms or nurseries. We describe the epidemiology of STEC O26 and examine evidence for a relationship between O26 and exposure to these settings. We analysed national surveillance data describing laboratory-confirmed STEC cases and public health incidents over the past 10 years to explore the incidence, clinical outcomes, and association with farms and nurseries for STEC O26 cases compared to STEC O157 and other serogroups. Between 2014 and 2023, the proportion of STEC notifications which were STEC O26 increased from 2% (19/956) to 12% (234/1946). After adjusting for age, we found no difference in the likelihood of farm or nursery attendance between O26 and O157 cases but a significantly higher risk of HUS in O26 (adjusted risk ratio 3.13 (2.18-4.51)). We demonstrate that STEC O26 is associated with the same risk of farm or nursery attendance as other STEC serogroups but a higher risk of severe morbidity. Our findings reinforce the need for improved surveillance of non-O157 STEC.
Tracking the Evolutionary Footprint of Mpox in West Africa: Phylogenetic and Clade Analysis
Oladipo EK, Adeyemo SF, Ogunniran JA, Popoola PO, Alabi VA and Opanike J
Social determinants and community-level risk factors in CA-MRSA transmission among disadvantaged populations in North America: A scoping review
Dembski SC, Giedroyc C, Karol N, Misra T and Guthrie JL
Community-acquired methicillin-resistant (CA-MRSA) is a significant public health concern, disproportionately affecting socioeconomically disadvantaged populations, including individuals experiencing poverty, homelessness, incarceration, and injection drug use. This scoping review synthesizes existing literature on factors influencing CA-MRSA occurrence and community transmission in these populations. A comprehensive search of PubMed, MEDLINE, and Scopus for studies published between January 2000 and February 2024 identified 3,223 articles, of which 40 met the inclusion criteria. Findings indicate that the CA-MRSA burden remains high, with community transmission influenced by factors, such as limited access to hygiene resources, structural barriers to care, and social network dynamics. Surveillance and intervention strategies remain largely healthcare-focused, with limited data on community-level transmission and risk. This review highlights the urgent need for targeted public health interventions and the adoption of expanded, innovative surveillance methods, such as genomic epidemiology, to better track and mitigate CA-MRSA transmission in vulnerable populations. As antibiotic resistance continues to rise, future research should prioritize longitudinal studies and community-based surveillance to develop effective, population-specific infection prevention, and control strategies.
Rift Valley fever seroprevalence in ruminants in Dhobley town, Lower Juba region, Somalia, in 2021
Hassan-Kadle AA, Osman AM, Yusuf AA, Shair MA, Hassan OA, Maluleke R, Van Schalkwyk A, Romito M, Lubisi A, Ibrahim AM and Vieira RFC
This study assesses the seroprevalence of Rift Valley fever (RVF) in ruminants in Dhobley, Somalia, following a 2021 outbreak in Kenya. Among 142 ruminants sampled, 4.9% were seropositive for RVF virus (RVFV) antibody, with IgM antibodies (1.4%) indicating recent exposure, though no cases were RT-PCR-positive. Unregulated livestock movement and limited surveillance pose significant risks for future outbreaks, underscoring the need for enhanced surveillance systems and One Health strategies.
Risk factors and diagnostic indicators for congenital syphilis: a Nationwide retrospective survey
Shimizu H, Furuichi M, Takeuchi N, Ito K, Funaki T, Ito Y, Mori M, Moriuchi H, Yamagishi T and Shinjoh M
This nationwide retrospective study in Japan aimed to identify risk factors and diagnostic indicators for congenital syphilis (CS) and improve diagnostic accuracy. Data were collected from 230 pregnant women diagnosed with syphilis and their infants between 2015 and 2024. Of these, 49 infants were diagnosed with definite or highly probable CS, while 73 infants with excluded CS served as the control group. Multivariable logistic regression analysis revealed two significant risk factors for CS: maternal treatment not completed more than 4 weeks before delivery (odds ratio [OR]: 7.20; 95% confidence interval [CI]: 1.38-37.56; p = 0.02) and elevated total IgM levels in the infant (>20 mg/dL) (OR: 65.31; 95% CI: 4.53-941.39; p = 0.002). When using infant rapid plasma reagin (RPR) ≥1 as a diagnostic indicator, sensitivity was 93.8% (n = 48). In contrast, the infant-to-mother RPR ratio ≥1 showed a lower sensitivity of 34.3%, with fewer cases available for analysis (n = 35) due to limited maternal data. These findings indicate that delayed maternal treatment and high total IgM levels in the infant are significant risk factors, while the infant's RPR titre serves as a useful diagnostic indicator for CS.
ESBL-producing gut colonisation and subsequent health-care associated bacteraemia in preterm newborns: a descriptive cohort with nested case-control study
Benboubker M, Oumokhtar B, Oukachou D, Elfakir S, Belchkar S, Rossi M, Massik A, Yahyaoui G, Moutaouakkil K and Hmami F
This descriptive and exploratory observational case series examined intestinal colonisation and subsequent bacteraemia due to ESBL-producing (ESBL-) in preterm neonates in Morocco. Prospective bacteriological cultures and antibiotic susceptibility testing were supported by phenotypic methods, including Brilliance ESBL Agar and the NG-Test CARBA-5 assay, for the rapid detection of ESBL and carbapenemase producers. Molecular analysis using PCR was also undertaken to identify specific resistance genes. A total of 567 rectal swabs were collected from 339 preterm neonates, yielding 293 isolates. ESBL-producing strains were identified in 53.6% of the neonates (182/339). Detected resistance genes included SHV (26.3%), CTX-M-1 (42.8%), TEM (30.2%), OXA-48 (50.0%), NDM(15.3%), and VIM (4.9%). Principal risk factors for colonisation were low birth weight (OR 1.69), very preterm birth (OR 6.24), enteral tube feeding (OR 2.02), and prolonged use of third-generation cephalosporins (OR 1.26). Among the neonates studied, 32 (9.4%) developed healthcare-associated bacteraemia, with 56.2% of these cases preceded by intestinal colonisation with ESBL- Clinically, severe respiratory distress and alveolar haemorrhage were strongly associated with increased mortality (aRR = 29.32 and 4.45, respectively). The findings highlight the clinical importance of early screening to guide infection control and antimicrobial stewardship in neonatal intensive care settings.
Risk factors for acute gastrointestinal illness in a Canadian population-based linkage cohort
Gilding AJ, Young I, Grant LE and Harris MA
Acute gastrointestinal illness (AGI) remains a significant public health issue and differences in risk based on a comprehensive set of sociodemographic characteristics remain poorly understood. Thus, this retrospective cohort study was conducted to identify the risk of incurring an AGI-related emergency department (ED) visit or inpatient hospitalization based on various sociodemographic factors. Linked respondents of Canadian Community Health Survey cycles 2.1, 3.1, and 2007-2015 were followed from their interview date until 31 December 2017, using the National Ambulatory Care Reporting System (NACRS) and the Discharge Abstract Database (DAD) to capture emergency ED visits and hospitalizations due to AGI, respectively. Effects of identified potential risk factors for the incidence of AGI-related ED visits or hospitalizations were estimated Cox proportional hazards regression to generate hazard ratios (HRs) with 95% confidence intervals (CIs). A total of 190,700 respondents were linked to NACRS and 470,700 were linked to DAD. Six per cent of respondents visited an ED and 2% were hospitalized for AGI. Fully-adjusted estimates revealed that high-risk groups with the strongest effects were people with poor self-perceived health (ED visits: HR 1.47 (95% CI 1.40-1.54), hospitalizations: HR 1.92 (95% CI 1.82-2.02)), and people living with at least one chronic condition (ED visits: HR 1.54 (95% CI 1.47-1.61), hospitalizations: HR 1.65 (95% CI 1.57-1.73)). This study identified risk factors for requiring hospital care for AGI in the Canadian context. Additional research is needed to investigate mechanisms for differential exposure to pathogens by sociodemographic characteristics that might lead to increased risks of AGI.
Mask wearing by COVID-19 index cases reduces SARS-CoV-2 transmission to household contacts
Godoy P, Pardos J, García Cenoz M, Parrón I, Martínez-Baz I, Ferras J, Rius C, Godoy S, Toledo D, Sanz I, Follia N, Miret C, Alsedà M, Plans-Rubió P, Carol M, Bes N, Sala MR, Caylà J, Muñoz-Almagro C, Castilla J, Domínguez A and
The objective of this study was to evaluate the impact on SARS-CoV-2 transmission prevention of mask wearing by index cases and their household contacts. A prospective study of SARS-CoV-2 transmission to household contacts aged ≥18 years was conducted between May 2022 and February 2024 in Spain. Contacts underwent a rapid antigen test on day zero and a real-time polymerase chain reaction test 7 days later if results were negative. The dependent variable was SARS-CoV-2 infection in contacts. Index case and contact mask use effects were estimated using the adjusted odds ratio (aOR) and its 95% confidence interval (CI). Studied were 230 household contacts, mean (standard deviation) age 53.3 (16.6) years, and 47.8% (110/230) women. Following index case diagnosis, 36.1% of contacts (83/230) used a mask, and 54.3% (125/230) were exposed to a mask-wearing index case. Infection incidence in contacts was 45.2% (104/230) and was lower in contacts exposed to mask-wearing index cases (36.0% vs. 56.2%;  < 0.002). The logistic regression model indicated a protective effect for contacts of both index case mask use (aOR = 0.31; 95% CI: 0.15-0.65) and vaccination (aOR = 0.24; 95% CI: 0.08-0.77). Index case mask use reduced SARS-CoV-2 transmission to contacts, while mask effectiveness was not observed for contacts.
Endemic potential of Chagas disease in the U.S. southwest: updated surveillance of infected Triatomines from the U.S.-Mexico border region
Farani PSG, Fritz A, Faier Pereira A, da Silva Ferreira M, de Melo Viana S, Crews C and Maldonado RA
, the etiological agent of Chagas disease, is a vector-borne parasite traditionally associated with sylvatic environments. We investigated the prevalence of in triatomines collected from El Paso County, Texas, and southern New Mexico. Specimens were morphologically identified as and subjected to quantitative PCR for parasite detection. Molecular sequencing of satellite and microsatellite DNA targets was performed to confirm species identity and assess strain lineage. Infected vectors were collected from both sylvatic and urban locations, including Franklin Mountains State Park and residential areas in El Paso (TX) and Las Cruces (NM). Of the 26 triatomines tested, 88.5% were positive for , representing a significant increase compared to a previous regional study, which reported an infection rate of 63.3%. The high prevalence of -infected , particularly in urban and peri-urban areas of El Paso and Las Cruces, underscores the increasing public health significance of Chagas disease along the U.S.-Mexico border. These findings highlight the urgent need for sustained vector surveillance, advanced molecular characterization, and focused public health interventions to reduce transmission risks and raise clinical awareness in affected regions.
COVIDmeter - a questionnaire-based symptom monitoring system for the surveillance of COVID-19 in Denmark, 2020-2023
Munch PK, Hansen CH, Møller FT, Nørgaard SK, Iversen AT, Helmuth IG and Ethelberg S
Early in the COVID-19 pandemic, Denmark launched COVIDmeter, a national participatory surveillance platform collecting real-time, self-reported symptoms from a community cohort, aimed to support early signal detection of COVID-like illness. This study describes the community cohort, the reported symptoms among persons testing positive and evaluates COVIDmeter's performance in detecting trends compared to other established surveillance indicators. A total of 143000 individuals registered as participants, of whom 98% completed at least one weekly questionnaire, resulting in approximately 5.8 million responses over the period from March 2020 to March 2023. Of those who tested positive, the most commonly reported symptoms overall were headache, fatigue, muscle or body aches, cough and fever. Trends in COVID-like illness followed similar patterns to other indicators, with COVID-like illness peaks often preceding increases in incidence and hospital admissions, suggesting early detection potential. The study demonstrated that participatory surveillance can serve as an early detection tool for tracking infection trends, particularly in the early stages of a pandemic. While subject to limitations such as selection bias and self-reporting inaccuracies and participatory symptom surveillance proved to be a rapid, scalable and cost-effective complement to traditional surveillance independent of virus testing, this highlights its relevance for future pandemic preparedness.
Evidence of very low hepatitis B virus prevalence in children and adolescents in Germany: National cross-sectional study, 2014-2017
Gillesberg Lassen S, Poethko-Müller C, Schlaud M, Slanina H, Schüttler CG, Stark K, Bremer V, Harder T and Dudareva S
Attaining the target of <0.1% HBsAg positives in children aged <5 years in vaccinated populations by 2030 is a WHO indicator of hepatitis B elimination. We aimed to calculate the prevalence of HBsAg- and anti-HBc-positive children and adolescents in the low-prevalence country of Germany. In total, 3567 children and adolescents aged 3-17 years participated in a national population based cross-sectional study. Data were collected between 2014 and 2017 using questionnaires and health examinations, including blood samples. Applying a weighted analysis to account for survey design and participant characteristics, we calculated the HBsAg and anti-HBc prevalence and described them by anti-HBs positivity. In total, 3007 participants had all three sero-markers measured. None were found HBsAg and anti-HBc positive. Seven (0.3%, 95% CI: 0.1-0.8) were anti-HBc positive and HBsAg negative; six were also anti-HBs positive. All anti-HBc-positive participants were aged ≥7 years and three had no migration background. Four anti-HBc-positive participants had known vaccination status; three had been vaccinated according to national recommendations. This very low hepatitis B virus sero-prevalence among children and adolescents indicates that Germany is reaching some hepatitis B virus elimination targets. We recommend maintaining preventive measures, in particular a high vaccination coverage, in order to reach hepatitis B elimination.
Text message surveillance for rapid outbreak detection: a novel public health approach
Franklin N, Hope K, Glass K and Kirk M
In large public health jurisdictions, only a small proportion of people infected with are interviewed due to resource constraints. As such, sources of illness are rarely found, and preventative action not implemented. We trialled alternative methods to contact notified salmonellosis cases to collect information on exposures and risks, focusing particularly on the feasibility of SMS (short message service)-based surveillance. Over five-years period we sequentially mailed letters, sent online surveys, and then text messages. The SMS approach was designed to assess the efficiency of a two-way personalized messaging model in gathering actionable public health data. The personalized SMS-follow-up model demonstrated the highest success: 56% of cases responded, enabling the identification and intervention of 10 distinct point-source outbreaks of SMS-based surveillance offers a novel, efficient, and acceptable method for collecting critical food exposure data in cases. In settings where resources are constrained, SMS can complement traditional case follow-up methods, enhancing both the timeliness and effectiveness of outbreak detection. Integrating this follow-up with routine clinical care could further enhance the acceptance and success of this method. This study highlights the promise of SMS in streamlining surveillance efforts and warrants further exploration for application to other infectious diseases.