Background The prioritization of U.S. health care personnel for early receipt of messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19), allowed for the evaluation of the effectiveness of these new vaccines in a real-world setting. Methods We conducted a test-negative case–control study involving health care personnel across 25 U.S. states. Cases were defined on the basis of a positive polymerase-chain-reaction (PCR) or antigen-based test for SARS-CoV-2 and at least one Covid-19–like symptom. Controls were defined on the basis of a negative PCR test for SARS-CoV-2, regardless of symptoms, and were matched to cases according to the week of the test date and site. Using conditional logistic regression with adjustment for age, race and ethnic group, underlying conditions, and exposures to persons with Covid-19, we estimated vaccine effectiveness for partial vaccination (assessed 14 days after receipt of the first dose through 6 days after receipt of the second dose) and complete vaccination (assessed ≥7 days after receipt of the second dose). Results The study included 1482 case participants and 3449 control participants. Vaccine effectiveness for partial vaccination was 77.6% (95% confidence interval [CI], 70.9 to 82.7) with the BNT162b2 vaccine (Pfizer–BioNTech) and 88.9% (95% CI, 78.7 to 94.2) with the mRNA-1273 vaccine (Moderna); for complete vaccination, vaccine effectiveness was 88.8% (95% CI, 84.6 to 91.8) and 96.3% (95% CI, 91.3 to 98.4), respectively. Vaccine effectiveness was similar in subgroups defined according to age (<50 years or ≥50 years), race and ethnic group, presence of underlying conditions, and level of patient contact. Estimates of vaccine effectiveness were lower during weeks 9 through 14 than during weeks 3 through 8 after receipt of the second dose, but confidence intervals overlapped widely. Conclusions The BNT162b2 and mRNA-1273 vaccines were highly effective under real-world conditions in preventing symptomatic Covid-19 in health care personnel, including those at risk for severe Covid-19 and those in racial and ethnic groups that have been disproportionately affected by the pandemic. (Funded by the Centers for Disease Control and Prevention.)

On May 14, 2021, this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr).Throughout the COVID-19 pandemic, health care personnel (HCP) have been at high risk for exposure to SARS-CoV-2, the virus that causes COVID-19, through patient interactions and community exposure (1). The Advisory Committee on Immunization Practices recommended prioritization of HCP for COVID-19 vaccination to maintain provision of critical services and reduce spread of infection in health care settings (2). Early distribution of two mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) to HCP allowed assessment of the effectiveness of these vaccines in a real-world setting. A test-negative case-control study is underway to evaluate mRNA COVID-19 vaccine effectiveness (VE) against symptomatic illness among HCP at 33 U.S. sites across 25 U.S. states. Interim analyses indicated that the VE of a single dose (measured 14 days after the first dose through 6 days after the second dose) was 82% (95% confidence interval [CI] = 74%-87%), adjusted for age, race/ethnicity, and underlying medical conditions. The adjusted VE of 2 doses (measured ≥7 days after the second dose) was 94% (95% CI = 87%-97%). VE of partial (1-dose) and complete (2-dose) vaccination in this population is comparable to that reported from clinical trials and recent observational studies, supporting the effectiveness of mRNA COVID-19 vaccines against symptomatic disease in adults, with strong 2-dose protection.A test-negative design case-control study of mRNA COVID-19 VE is underway, with HCP being enrolled at 33 sites across 25 U.S. states; the planned interim analysis presented in this report includes data collected during January-March 2021.* A majority (75%) of enrolled HCP worked at acute care hospitals (including emergency departments), 25% worked in outpatient or specialty clinics, and <1% worked in long-term care facilities and urgent care * https://www.cdc.gov/vaccines/covid-19/downloads/hcp-early-phaseprotocol-508.pdf

ABSTRACT. Many human activities in Canada kill wild birds, yet the relative magnitude of mortality from different sources and the consequent effects on bird populations have not been systematically evaluated. We synthesize recent estimates of avian mortality in Canada from a range of industrial and other human activities, to provide context for the estimates from individual sources presented in this special feature. We assessed the geographic, seasonal, and taxonomic variation in the magnitude of national-scale mortality and in population-level effects on species or groups across Canada, by combining these estimates into a stochastic model of stage-specific mortality. The range of estimates of avian mortality from each source covers several orders of magnitude, and, numerically, landbirds were the most affected group. In total, we estimate that approximately 269 million birds and 2 million nests are destroyed annually in Canada, the equivalent of over 186 million breeding individuals. Combined, cat predation and collisions with windows, vehicles, and transmission lines caused > 95% of all mortality; the highest industrial causes of mortality were the electrical power and agriculture sectors. Other mortality sources such as fisheries bycatch can have important local or species-specific impacts, but are relatively small at a national scale. Mortality rates differed across species and families within major bird groups, highlighting that mortality is not simply proportional to abundance. We also found that mortality is not evenly spread across the country; the largest mortality sources are coincident with human population distribution, while industrial sources are concentrated in southern Ontario, Alberta, and southwestern British Columbia. Many species are therefore likely to be vulnerable to cumulative effects of multiple human-related impacts. This assessment also confirms the high uncertainty in estimating human-related avian mortality in terms of species involved, potential for population-level effects, and the cumulative effects of mortality across the landscape. Effort is still required to improve these estimates, and to guide conservation efforts to minimize direct mortality caused by human activities on Canada's wild bird populations. As avian mortality represents only a portion of the overall impact to avifauna, indirect effects such as habitat fragmentation and alteration, site avoidance, disturbance, and related issues must also be carefully considered.RÉSUMÉ. Au Canada, de nombreuses activités d'origine anthropique entraînent la mort d'oiseaux sauvages, mais l'ampleur relative de la mortalité selon les diverses sources et leurs conséquences sur les populations d'oiseaux n'ont pas été évaluées systématiquement. Nous avons compilé des estimations récentes de mortalité aviaire au Canada causée par des activités industrielles et d'autres origines anthropiques afin de mettre en contexte les estimations calculées pour chacune des sources de mortalité présentées dans ce numéro spécial. Nous avons évalué la var...

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, has infected more than 25 million Americans, leading to over 420,000 deaths. 1 The Centers for Disease Control and Prevention reports over 378,000 cases of COVID-19 in U.S. health care personnel (HCP) with 1,286 deaths. 2 By summer 2020, an estimated 4.6% of academic emergency department (ED)

Summary 0[ Many species of altricial birds hatch their young asynchronously within broods[ Although there are many potential bene_ts to parents\ hatching asynchrony reduces the growth and often the survival of last!hatched nestlings[ The consequences of hatching asynchrony on the growth\ size at~edging and survival of male and female nestlings of an Australian parrot\ the crimson rosella "Platycercus elegans# were examined[ 1[ Crimson rosella broods hatched over 0=4Ð6 days\ creating mass hierarchies where _rst!hatched chicks were up to seven times larger than last!hatched chicks[ Hatching asynchrony and mass hierarchies increased over the breeding season\ but were not strongly correlated with brood size[ 2[ Male chicks grew faster and were larger at~edging than females[ Growth rates did not di}er between hatching ranks[ Chicks of all ranks were of equal sizes at~edging\ but last!hatched male chicks had lower~edging mass in pairwise analyses[ Female mass at~edging did not decrease with hatching rank[ Chick growth rates and size or mass at~edging were not related to hatching asynchrony\ mass or size hierarchies in broods\ brood size\ laying date or year in mixed!model analyses[ 3[ Last!hatched chicks had the same post!~edging survival as other chicks\ however\ they were more likely to die during the nestling period[ Increased mortality of last! hatched nestlings occurred only at hatching and chicks had equal mortality rates over the remainder of the nestling period[ Early brood reduction was not associated with brood size or hatching asynchrony but increased over the breeding season\ and in broods with high hatching success[ 4[ Hatching asynchrony in rosellas\ unlike in most previous studies\ did not lead to poor growth and subsequent survival of last!hatched chicks[ This suggests that the costs of hatching asynchrony are low in this species and that selective feeding by parents may increase the growth and survival of last!hatched chicks[ 5[ Reduced growth and survival of later hatched chicks is not an inevitable conse! quence of asynchronous hatching^however\ the costs to parents of overcoming com! petitive interactions between chicks may be higher than the bene_ts in most species[ Key!words] growth rates\ hatching asynchrony\ parental allocation\ parrots\ Pla! tycercus elegans[ Journal of Animal Ecology "0888# 57\ 155Ð170