The antibiotic trimethoprim acts as a folate antagonist. Since trophoblasts are very sensitive to drugs that interfere with the folic acid cycle and thereby inhibit DNA synthesis, use of trimethoprim during the first trimester could be associated with miscarriage. A nationwide cohort study including all women in Denmark with a registered pregnancy between 1997 and 2005 was conducted. We used nationwide registers to identify all women giving birth, having a record of miscarriage or induced abortion. Data on exposure to trimethoprim were obtained from the National Prescription Register. Cox proportional hazard regression analysis with exposure to trimethoprim as a time-dependent variable was used to estimate the risk of miscarriage. The adjusted hazard ratio of having a miscarriage after exposure to trimethoprim in the first trimester compared to non-exposure was 2·04 (95% confidence interval 1·43–2·91). Our results indicate that trimethoprim exposure in the first trimester is associated with a doubling of the hazard of miscarriage.

Incidence of various diseases can increase following a flood. We aimed to identify professionals in Copenhagen who became ill after contact with 2 July 2011 floodwater/sediment and determine risks and protective factors associated with illness. We conducted a cohort study of employees engaged in post-flood management activities. Participants completed a questionnaire collecting information about demographics, floodwater/sediment exposure, compliance with standard precautions, and symptoms of illness. Overall, 257 professionals participated, with 56 (22%) cases. Risk of illness was associated with not washing hands after floodwater/sediment contact [relative risk (RR) 2·45], exposure to floodwater at work and home (RR 2·35), smoking (RR 1·92), direct contact with floodwater (RR 1·86), and eating/drinking when in contact with floodwater (RR 1·77). Professionals need to follow standard precautions when in contact with floodwater/sediment, especially proper hand hygiene after personal protective equipment use and before eating/drinking and smoking.

Meningococcal meningitis is a major public health problem in the African Belt. Despite the obvious seasonality of epidemics, the factors driving them are still poorly understood. Here, we provide a first attempt to predict epidemics at the spatio-temporal scale required for in-year response, using a purely empirical approach. District-level weekly incidence rates for Niger (1986–2007) were discretized into latent, alert and epidemic states according to pre-specified epidemiological thresholds. We modelled the probabilities of transition between states, accounting for seasonality and spatio-temporal dependence. One-week-ahead predictions for entering the epidemic state were generated with specificity and negative predictive value >99%, sensitivity and positive predictive value >72%. On the annual scale, we predict the first entry of a district into the epidemic state with sensitivity 65·0%, positive predictive value 49·0%, and an average time gained of 4·6 weeks. These results could inform decisions on preparatory actions.

Abortion and stillbirth are important reproductive disorders in the dairy industry and are often caused by infectious agents. This study investigated whether bovine viral diarrhoea virus (BVDV), Brucella spp., and Neospora caninum are associated with abortion and/or stillbirth in dairy cattle in Ethiopia. Dairy cattle from 99 farms were categorized as cases (n = 134) or controls (n = 268) according to reproductive data. Blood samples were screened for antibodies for these infectious agents. The overall proportion of cattle that were seropositive for BVDV, Brucella spp., and N. caninum was 11·7%, 3·2%, and 17·2%, respectively. Seropositivity for BVDV and Brucella spp. was similar for cases and controls, but significantly more cases were seropositive for N. caninum (29·8%) than controls (10·8%). This is the first report demonstrating N. caninum is common in dairy cattle in Ethiopia, and is probably a greater impediment to reproductive success in Ethiopian dairy farms than either BVDV or Brucella spp.

The objective of this study was to determine the optimal number of respiratory samples per outbreak to be tested for institutional respiratory outbreaks in Ontario. We reviewed respiratory samples tested for respiratory viruses by multiplex PCR as part of outbreak investigations. We documented outbreaks that were positive for any respiratory viruses and for influenza alone. At least one virus was detected in 1454 (85·2%) outbreaks. The ability to detect influenza or any respiratory virus increased as the number of samples tested increased. When analysed by chronological order of when samples were received at the laboratory, percent positivity of outbreaks testing positive for any respiratory virus including influenza increased with the number of samples tested up to the ninth sample, with minimal benefit beyond the fourth sample tested. Testing up to four respiratory samples per outbreak was sufficient to detect viral organisms and resulted in significant savings for outbreak investigations.