The 1st year of the COVID-19 epidemic in Estonia: an interrupted time series of population based nationwide cross-sectional studies.

BackgroundDecisions about the continued need for control measures and the effect of introducing COVID-19 vaccinations rely on accurate and population-based data on SARS-CoV-2 positivity and risk factors for testing positive. MethodsIn this interrupted time series of population-based nationwide cross-sectional studies, data from nasopharyngeal testing and questionnaires were used to estimate the SARS-CoV-2 RNA prevalence and factors associated with test positivity over the 1st year of the COVID-19 epidemic. The study is registered with the ISRCTN Registry, ISRCTN10182320. ResultsBetween April 23, 2020 and February 2, 2021, results were available from 34,915 individuals and 27,870 samples from 11 consecutive studies. The percentage of people testing positive for SARS-CoV-2 decreased from 0.27% (95% CI 0.10% - 0.59%) in April to 0.04% (95% CI 0.00% - 0.22%) by the end of May and remained very low (0.01%, 95% CI 0.00% - 0.17%) until the end of August, followed by an increase since November (0.37%, 95% CI 0.18% - 0.68%) that escalated to 2.69% (95% CI 2.08% - 2.69%) in January 2021. In addition to substantial change in time, an increasing number of household members (for one additional OR 1.15, 95% CI 1.02-1.29), reporting current symptoms of COVID-19 (OR 2.21, 95% CI 1.59-3.09), and completing questionnaire in the Russian language (OR 1.85, 95% CI 1.15-2.99) were associated with increased odds for SARS-CoV-2 RNA positivity. ConclusionsSARS-CoV-2 population prevalence needs to be carefully monitored as vaccine programmes are rolled out in order to inform containment decisions. Strengths and limitations of this studyO_LIOur study relies upon nation-wide and population-based data on SARS-CoV-2 prevalence, and presents changes in prevalence over the whole 1st year of the Covid-19 epidemic. C_LIO_LIOur analysis of SARS-CoV-2 infection risk factors is not limited to notification or health care-based case data. C_LIO_LISelection bias may have been introduced as a result of low response rate. The direction of bias is unclear, but most likely operates rather uniformly over the period of observation, though this presents less of a threat to the SARS-CoV-2 prevalence trend analysis. C_LIO_LIOur data could be used to adequately project the future course of the SARS-CoV-2 epidemic and the effect of control measures. C_LI

Genome-wide association meta-analysis of fish and EPA+DHA consumption in 17 US and European cohorts.

BACKGROUND: Regular fish and omega-3 consumption may have several health benefits and are recommended by major dietary guidelines. Yet, their intakes remain remarkably variable both within and across populations, which could partly owe to genetic influences. OBJECTIVE: To identify common genetic variants that influence fish and dietary eicosapentaenoic acid plus docosahexaenoic acid (EPA+DHA) consumption. DESIGN: We conducted genome-wide association (GWA) meta-analysis of fish (n = 86,467) and EPA+DHA (n = 62,265) consumption in 17 cohorts of European descent from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium Nutrition Working Group. Results from cohort-specific GWA analyses (additive model) for fish and EPA+DHA consumption were adjusted for age, sex, energy intake, and population stratification, and meta-analyzed separately using fixed-effect meta-analysis with inverse variance weights (METAL software). Additionally, heritability was estimated in 2 cohorts. RESULTS: Heritability estimates for fish and EPA+DHA consumption ranged from 0.13-0.24 and 0.12-0.22, respectively. A significant GWA for fish intake was observed for rs9502823 on chromosome 6: each copy of the minor allele (FreqA = 0.015) was associated with 0.029 servings/day (~1 serving/month) lower fish consumption (P = 1.96x10-8). No significant association was observed for EPA+DHA, although rs7206790 in the obesity-associated FTO gene was among top hits (P = 8.18x10-7). Post-hoc calculations demonstrated 95% statistical power to detect a genetic variant associated with effect size of 0.05% for fish and 0.08% for EPA+DHA. CONCLUSIONS: These novel findings suggest that non-genetic personal and environmental factors are principal determinants of the remarkable variation in fish consumption, representing modifiable targets for increasing intakes among all individuals. Genes underlying the signal at rs72838923 and mechanisms for the association warrant further investigation.