This study examined whether coronavirus disease 2019 (COVID-19) infection experience enhances preventive behaviour (i.e., hand disinfection and mask-wearing), with risk perception acting as a mediating factor. The study included participants aged ≥18 years residing in Japan, enrolled in a 30-wave cohort study conducted from January 2020 to March 2024. Using propensity score matching, 135 pairs of participants with and without infection were extracted, adjusting for dread and unknown risk perception, preventive behaviours, sociopsychological variables, and individual attributes. Comparisons of risk perception and preventive behaviour were made between groups post-infection experience, and mediation analysis was conducted to test whether risk perception mediated the effect of infection experience on preventive behaviour. Following the infection experience, participants in the infection group reported significantly higher scores for one item of unknown risk perception and a greater proportion of mask-wearing. The indirect effect of infection experience on mask-wearing, mediated by the unknown risk perception item, was significant. COVID-19 infection experience increased perceptions of unknowable exposure, which in turn promoted mask-wearing behaviour. Incorporating insights from personal infection experiences into public health messaging may enhance risk perception and promote preventive behaviour among non-infected individuals, offering a novel approach to infection control at the population level.

Effectiveness of nirsevimab against respiratory syncytial virus (RSV) hospitalization during the 2024/2025 season in Spain was estimated using a test-negative design (TND) and hospital-based respiratory infections surveillance data. Children born between 1 April 2024 and 31 March 2025 and hospitalized with severe respiratory infection between the start of the 2024 immunization campaign (regionally variable, between 16 September and 1 October 2024) and 31 March 2025 were systematically RT-PCR RSV-tested within 10 days of symptom onset and classified as cases if positive or controls if negative. Nirsevimab effectiveness ((1 − odds ratio) × 100) was estimated using logistic regression, adjusted for admission week, age, sex, high-risk factors, and regional RSV hospitalization rate. We included 199 cases (68.8% immunized) and 360 controls (86.4% immunized). Overall effectiveness was 65.5% (95% confidence interval: 45.2 to 78.3). Effectiveness was similar among infants born before and after the campaign start (63.6% vs. 70.4%, respectively). We found an unexpected early decrease in effectiveness with increasing time since immunization and age, albeit with wide confidence intervals for some groups. Strong age–period–cohort effects and potential sources of bias were identified, highlighting the need to further explore methodological challenges of implementing the TND in the dynamic population of newborns.

Our study assessed the link between gastrointestinal (GI) infections in England and the Eat Out to Help Out scheme (EOHO), a government subsidy created to encourage people to eat out during COVID-19 pandemic (03–30 August 2020). We studied national laboratory data between January 2015 and December 2020. We used time series change point analysis to see if there were shifts in reported cases of specific GI infections (Campylobacter spp., Escherichia coli O157, and non-typhoidal Salmonella spp.) associated with the timing of the scheme. Our analysis uniquely applied the Pruned Exact Linear Time method, with generalized linear models to a national dataset of GI infections. This revealed increases in cases closely aligned to the timing of the easing of COVID-19 restrictions, prior to the introduction of the EOHO scheme. Our study showed the scheme had no measurable impact, as there was no significant change on reported cases. Substantial reductions in cases after the first lockdown, followed by an increase as restrictions were phased out, show the wider impact of COVID-19 control measures, for example, public information campaigns aimed at improving hand-hygiene. These findings highlight the complicated interactions between COVID-19 control measures, the public’s behaviour, and the spread of GI infections.

There is a positive association between bacteraemia with Streptococcus bovis–Streptococcus equinus complex (SBSEC) and colorectal cancer (CRC). However, the relationship between the timing of SBSEC bacteraemia and CRC is not well-established. Associations with other gastrointestinal cancers have also been suggested. Using national registries, we retrospectively examined the incidence of CRC and other gastrointestinal cancers after SBSEC-bacteraemia in Sweden 2010–2019, and analysed the timing, characteristics, and prognosis of diagnosed CRC. Individuals with SBSEC-bacteraemia were matched to randomly selected controls from the general population at a 1:10 ratio. Cox-regression determined CRC hazard ratios (HR). In total, 908 individuals with SBSEC-bacteraemia were identified and 9,080 controls, of whom 75/908 (8.3%) and 168/9080 (1.9%) respectively had previously diagnosed CRC (p < 0.01). During follow-up of individuals without previous CRC, CRC was diagnosed in 45/833 (5.4%) individuals with SBSEC and 114/8912 (1.3%) controls (p < 0.01). The HR of CRC diagnosis for SBSEC was 10.3 (95% CI 6.7–15.8) overall and 19.8 (95% CI 11.1–35.3) during the first year of follow-up. In conclusion, there was an increased incidence of CRC, and most were diagnosed within the first year. Neither the tumour location, −stage, or -grade of diagnosed CRC nor the rates of other gastrointestinal cancers differed significantly.

Syphilis has re-emerged as a public health threat during the 21st century, and updated knowledge of the epidemic and its drivers is needed to halt this worrying development. We present data on the incidence of syphilis in the south Swedish region Skåne from 2007 to 2022 to determine the burden of disease, changes in risk groups, as well as routes for testing. To get a picture of the burden of syphilis, both early (notifiable) syphilis and cases of non-notifiable (late) symptomatic syphilis were included in this register-based study. Mann–Kendall trend analysis (MK) was used to determine statistical significance over time. In all, 584 cases of syphilis were included in the study. The overall syphilis incidence in Skåne increased from 3.1 cases/100000 population in 2007 to 6.3 in 2022 (MK z-stat: 2.57; p = 0.010). The highest increase in absolute numbers was among men who have sex with men (MSM), from eight cases annually in 2007 to 62 in 2022, but also for heterosexually transmitted men and women, with under ten cases yearly from 2007 through 2019 to 22 cases in 2022. We also found that transmission within Sweden was common, indicating that local measures are needed to curb this epidemic.