18 August 2021

• Public health experts from the US Department of Health and Human Services issue a statement supporting the need for booster shots, due to waning immunity, the rise of the more transmissible Delta variant, and concerns that protection against severe COVID-19, hospitalization and death could diminish in the coming months – especially for people vaccinated at the beginning of 2021. The statement included information on a plan to start offering boosters in Q3 2021 for people vaccinated eight months ago, included healthcare providers, nursing home residents and other senior citizens. Source

• A pre-print study is released on vaccine effectiveness against new SARS-CoV-2 infections in the UK, based on data from the Office for National Statistics COVID-19 Infection Survey, which used on results from pre-scheduled PCR testing. Researchers looked at 384,543 PCR results during the Alpha-dominant period (1 December to 16 May) and 358,983 PCR results during the Delta-dominant period (17 May to 1 August). They found that vaccine efficacy was high during the Alpha-dominant period, but when Delta became dominant, the AstraZeneca vaccine was significantly less effective than the Pfizer/BioNTech vaccine – although effectiveness of the Pfizer/BioNTech vaccine waned rapidly, becoming similar to AstraZeneca’s after 4-5 months. Peak viral loads among fully vaccinated people infected with the  Delta variant  were similar to those among unvaccinated people, leading the authors to note that this “…further argues for vaccinating as many of the population as possible, since those not vaccinated may not be protected by as substantial reductions in transmission among the immunized population as seen other infections, making herd immunity likely unachievable for emerging variants and requiring efforts to protect individuals themselves.” Source

• The US CDC publishes a report on the effectiveness of the Pfizer/BioNTech and Moderna coronavirus vaccines among nursing home residents before and during circulation of the Delta variant. During the pre-Delta era (1 March to 9 May), an analysis of 17,407 weekly reports from 3,862 facilities found that full vaccination was 74.4 percent effective. From 10 May – 20 June, an analysis of 33,160 weekly reports from 11,581 facilities found that vaccine effectiveness dropped to 67.5 percent. From 21 June to 1 August, an analysis using 85,593 weekly reports from 14,917 facilities found that effectiveness dropped to 53.1percent. Of the 6.879 cases of COVID-19 reported from 1 March until 1 August, 2,113 (30.7 percent) occurred among unvaccinated nursing home residents; the remaining cases were among those fully vaccinated with Pfizer/BioNTech (37.8 percent, or 2,603) or Moderna (18.9 percent, or 1,302) and the remaining 12 percent were among residents with “other” vaccination status. Overall, vaccine efficacy was similar. The authors noted that they could not differentiate between the effects of waning immunity and the Delta variant, particularly because widespread circulation of the Delta variant occurred at six months after vaccine introduction. The authors noted the need for multiprong prevention strategies for nursing home residents (infection control, testing and vaccination of staff members, residents and visitors, and suggested that an additional dose of vaccine could be considered for residents of nursing homes and long-term care facilities. Source 

• The US CDC publishes a report on the sustained effectiveness of coronavirus vaccines from Pfizer/BioNTech and Moderna against hospitalization for COVID-19 from March to July of 2021, based on data from 3.089 people. For 2-12 weeks after vaccination, mRNA vaccines were 86 percent effective at preventing hospitalization from COVID-19, and 84 percent effective at 12-24 weeks (although their effectiveness at preventing hospitalization dropped to 63 percent among people with immunocompromising conditions). The authors noted that vaccination should be offered to all eligible people. Source

• WHO reports that fake versions of Covishield – the AstraZeneca vaccine produced by India’s Serum Institute – have been seized in Africa and India. Source 

• Pope Francis has joined religious leaders from Muslim, African American and Orthodox Jewish communities to urge coronavirus vaccination in a video, saying that is “an “an act of love.” Source

• As the Delta variant continues to surge across Japan, the government extended the state of emergency covering Tokyo and five other areas from 31 August to to 12 September and expanded it to include seven more prefectures. Restaurants and bars are asked to shut, and those that do not serve alcohol are asked to close at 8 p.m. under the threat of possible fines. But large portions of the public have become unwilling to stay home, and many bars and restaurants are not complying, because they fear that they will be unable to reopen. In response, Prime Minister Yoshihide Suga announced that the government will prepare additional subsidies of 300 billion yen ($2.7 billion) to help struggling businesses. Source

• In Israel, where 78 percent of residents are fully vaccinated, the Delta variant is causing a surge of COVID-19 cases, including among early vaccine recipients – elderly people, who may have weakened immune systems. In June, the country removed preventive measures including indoor masking; the government has been slow to respond to rising cases in June and July and is now hoping that booster shots will curb the spread of the virus. Source         

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