Social, demographic and behavioural determinants of SARS-CoV-2 infection: a case-control study carried out during mass community testing of asymptomatic individuals in South Wales, December 2020.

Between 21 November and 22 December 2020, a SARS-CoV-2 community testing pilot took place in the South Wales Valleys. We conducted a case-control study in adults taking part in the pilot using an anonymous online questionnaire. Social, demographic and behavioural factors were compared in people with a positive lateral flow test (cases) and a sample of negatives (controls). A total of 199 cases and 2621 controls completed a questionnaire (response rates: 27.1 and 37.6% respectively). Following adjustment, cases were more likely to work in the hospitality sector (aOR 3.39, 95% CI 1.43-8.03), social care (aOR 2.63, 1.22-5.67) or healthcare (aOR 2.31, 1.29-4.13), live with someone self-isolating due to contact with a case (aOR 3.07, 2.03-4.62), visit a pub (aOR 2.87, 1.11-7.37) and smoke or vape (aOR 1.54, 1.02-2.32). In this community, and at this point in the epidemic, reducing transmission from a household contact who is self-isolating would have the biggest public health impact (population-attributable fraction: 0.2). As restrictions on social mixing are relaxed, hospitality venues will become of greater public health importance, and those working in this sector should be adequately protected. Smoking or vaping may be an important modifiable risk factor.

Risk factors for outbreaks of COVID-19 in care homes following hospital discharge: A national cohort analysis.

BACKGROUND: The population of adult residential care homes has been shown to have high morbidity and mortality in relation to COVID-19. METHODS: We examined 3115 hospital discharges to a national cohort of 1068 adult care homes and subsequent outbreaks of COVID-19 occurring between 22 February and 27 June 2020. A Cox proportional hazards regression model was used to assess the impact of time-dependent exposure to hospital discharge on incidence of the first known outbreak, over a window of 7-21 days after discharge, and adjusted for care home characteristics, including size and type of provision. RESULTS: A total of 330 homes experienced an outbreak, and 544 homes received a discharge over the study period. Exposure to hospital discharge was not associated with a significant increase in the risk of a new outbreak (hazard ratio 1.15, 95% CI 0.89, 1.47, P = .29) after adjusting for care home characteristics. Care home size was the most significant predictor. Hazard ratios (95% CI) in comparison with homes of <10 residents were as follows: 3.40 (1.99, 5.80) for 10-24 residents; 8.25 (4.93, 13.81) for 25-49 residents; and 17.35 (9.65, 31.19) for 50+ residents. When stratified for care home size, the outbreak rates were similar for periods when homes were exposed to a hospital discharge, in comparison with periods when homes were unexposed. CONCLUSION: Our analyses showed that large homes were at considerably greater risk of outbreaks throughout the epidemic, and after adjusting for care home size, a discharge from hospital was not associated with a significant increase in risk.

Outbreak of mumps in a school setting, United Kingdom, 2013.

Effective protection against mumps can be achieved through 2 doses of the measles-mumps-rubella (MMR) vaccine. However, outbreaks of mumps have recently been described among populations with high vaccination coverage, including 2 doses of MMR. Here we describe an outbreak at a school in the East of England, UK. The school was attended by 540 pupils aged 10-19 years and had 170 staff. In total, 28 cases of mumps (24 pupils and 4 staff) were identified during 10 January to 16 March 2013. Vaccination status was known in 25 of the cases, and among these 21 (84.0%) had a documented history of 2 doses of MMR while the remaining had a history of one dose (2/25 cases, 8.0%) or no doses (2/25, 8.0%) of MMR. An outbreak control team recommended that MMR vaccine should be offered to all pupils whose parents consented to it, regardless of previous vaccination status. Additional MMR vaccines were administered to 103 pupils, including 76 (73.8%) third doses of MMR. Offering an additional dose of MMR appeared to be acceptable to parents, and we found it feasible to administer the intervention in a timely manner with resources from the local Public Health Centre (Primary Care Trust). An additional dose of MMR to all individuals at risk can be considered as an acceptable control measure for mumps outbreaks in schools even if the vaccination coverage is high. However, further evidence on the effectiveness, acceptability, and safety of this intervention is needed.

Acute hepatitis A in an elderly patient after care worker travel to high endemicity country.

Hepatitis A virus (HAV) is considered one of the most important vaccine-preventable diseases in travelers. HAV spreads from person to person via the fecal-oral route and gives rise to an estimated 1.4 million cases worldwide each year. In developing countries with poor sanitary conditions people tend to be infected during childhood and have few symptoms, whereas in developed countries with good sanitary conditions fewer people develop immunity during childhood. This leads to susceptible populations of adults, who are also more prone to severe complications. Here we describe two confirmed cases of hepatitis A associated with a nursing home. The index case was a care worker who had recently traveled to a high-endemicity country, and the second case was a resident at the nursing home where the index case worked. Both cases had an identical genotype IIIA strain, consistent with a transmission event. Current policy does not include a requirement for hepatitis A vaccine in care workers who travel to high endemicity countries despite the fact that infected care workers can potentially spread the disease to elderly patients and other groups at risk of severe complications from HAV infection. We suggest that employers should consider hepatitis A vaccine upon employment; particularly in care workers who plan to visit areas where HAV is known to be endemic.

Seasonal influenza risk in hospital healthcare workers is more strongly associated with household than occupational exposures: results from a prospective cohort study in Berlin, Germany, 2006/07.

BACKGROUND: Influenza immunisation for healthcare workers is encouraged to protect their often vulnerable patients but also due to a perceived higher risk for influenza. We aimed to compare the risk of influenza infection in healthcare workers in acute hospital care with that in non-healthcare workers over the same season. METHODS: We conducted a prospective, multicentre cohort study during the 2006/07 influenza season in Berlin, Germany. Recruited participants gave serum samples before and after the season, and completed questionnaires to determine their relevant exposures and possible confounding factors. The main outcome measure was serologically confirmed influenza infection (SCII), defined as a fourfold or greater rise in haemagglutination inhibition antibody titres to a circulating strain of influenza (with post-season titre at least 1:40).Weekly mobile phone text messages were used to prompt participants to report respiratory illnesses during the influenza season. A logistic regression model was used to assess the influence of potential risk factors. RESULTS: We recruited 250 hospital healthcare workers (mean age 35.7 years) and 486 non-healthcare workers (mean age 39.2 years) from administrative centres, blood donors and colleges.Overall SCII attack rate was 10.6%. Being a healthcare worker was not a risk factor for SCII (relative risk 1.1, p = 0.70). The final multivariate model had three significant factors: living with children (odds ratio [OR] 3.7, p = 0.005), immunization (OR 0.50, p = 0.02), and--among persons living in households without children--ownership of a car (OR 3.0, p = 0.02). Living with three or more children (OR 13.8, p < 0.01) was a greater risk than living with one or two children (OR 5.3, p = 0.02). 30% of participants with SCII reported no respiratory illness. Healthcare workers were at slightly higher risk of reporting any respiratory infection than controls (adjusted OR 1.3, p = 0.04, n = 850). CONCLUSIONS: Our results suggest that healthcare workers in hospitals do not have a higher risk of influenza than non-healthcare workers, although their risk of any respiratory infection is slightly raised. Household contacts seem to be more important than exposure to patients. Car ownership is a surprise finding which needs further exploration. Asymptomatic infections are common, accounting for around a third of serologically confirmed infections.

Bacterial populations in the vaginas of healthy adolescent women.

Given that the microbiota of the healthy vagina plays an important role in the maintenance of health, it follows that an understanding of its composition and development may offer insights into the etiology and prevention of disease. In contrast to previous studies, this study exclusively investigated the structure and composition of adolescent vaginal bacterial communities. In this report, the vaginal bacterial communities of 90 menarcheal adolescents, ages 13-18y, were characterized using terminal restriction fragment length polymorphisms (T-RFLP) of 16S rRNA genes. Further characterization involved cluster analysis of the T-RFLP data to identify the number of different kinds of microbial communities found among the adolescents sampled, and phylogenetic analysis of 16S rRNA gene sequences cloned from samples representative of each cluster. We report the identification of four major clusters that accounted for 96.7% of the cohort. In general, these clusters could be divided into those dominated by Lactobacillus spp. and those dominated by a variety of lactic acid producing, anaerobic bacterial types such as Atopobium vaginae and Streptococcus spp. The compositional and structural similarity of the vaginal microbiota of menarcheal adolescents and adults suggests that the vaginal microbiota does not change significantly after the onset of menarche.