12/18—Does Contact Tracing Work? Quasi-Experimental Evidence from an Excel Error
Does Contact Tracing Work? Quasi-Experimental Evidence from an Excel Error in England
[Preprint.] This paper exploits quasi-random variation in COVID-19 contact tracing. Between September 25 and October 2, 2020, a total of 15,841 COVID-19 cases in England (around 15 to 20% of all cases) were not immediately referred to the contact tracing system due to a data processing error. We show that more affected areas subsequently experienced a drastic rise in new COVID-19 infections and deaths alongside an increase in the positivity rate and the number of test performed, as well as a decline in the performance of the contact tracing system. Conservative estimates suggest that the failure of timely contact tracing due to the data glitch is associated with more than 125,000 additional infections and over 1,500 additional COVID-19-related deaths.
Remembering seasonal coronaviruses
SARS-CoV-2 has differential effects according to age, with symptomatic and severe infections mostly occurring in older adults. One possible explanation for this variation is that children and younger adults have more preexisting immunity against seasonal human coronaviruses (HCoVs) that cross-react with SARS-CoV-2, providing protection from severe and even symptomatic SARS-CoV-2 infection.
Persistence of IgG response to SARS-CoV-2
Little is known about the duration and protective capacity of the humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In studies from Iceland and the USA, antibodies against SARS-CoV-2 did not decline within 4 months after diagnosis. However, other studies have reported rapid waning of antibodies within 3–4 months. Since April 22, 2020, we have been following up a representative cohort of 850 health-care workers from 17 Belgian hospitals. Based on data currently available, a rapid decline of SARS-CoV-2 IgG seropositivity or neutralising capacity has not been seen.
Roman Catholic Diocese of Brooklyn v. Cuomo — The Supreme Court and Pandemic Controls
On November 25, 2020, as Americans prepared to celebrate Thanksgiving during a pandemic, the U.S. Supreme Court, by a 5-to-4 vote, undermined states’ ability to control that pandemic. In Roman Catholic Diocese of Brooklyn v. Cuomo,1 the Court temporarily enjoined limits on in-person religious worship imposed by New York Governor Andrew Cuomo.
Reduced mortality in New Zealand during the COVID-19 pandemic
We compared weekly death rates from 2015 to 2020. Reported weekly all-cause mortality in 2020 was similar to mortality in 2015–19 until week 17 (ie, the fifth week of public health measures) when mortality fell below historical rates, a trend which is still evident at week 42. There were a total of 25 deaths from COVID-19 from the start of the pandemic in New Zealand to week 42. As the costs and benefits of strict public health measures are debated, New Zealand's low all-cause mortality during this period is a striking observation.
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