12/16—USA averaging 2,430 deaths per day (1 death every 36 seconds)

COVID-19 updates from the Johns Hopkins Center for Health Security
[Situation report.] The US reported a new single-day record for daily incidence on December 11, with more than 244,000 new cases. In terms of mortality, the US is averaging 2,430 deaths per day, which corresponds to 1 US death every 36 seconds.

Epidemiological and cohort study finds no association between COVID-19 and Guillain-Barré syndrome
The epidemiology of GBS cases reported to the UK National Immunoglobulin Database was studied from 2016 to 2019 and compared to cases reported during the COVID-19 pandemic. GBS incidence has fallen during the pandemic.

COVID-19 vaccine and Guillain-Barré syndrome: let’s not leap to associations
Why does GBS rear its head in the context of the SARS-Cov-2 pandemic and vaccination programmes? To understand this, we need to revisit the 1976/77 USA/New Jersey/76 vaccination programme that brought GBS to world-wide attention. The vaccine was associated with a spike in cases of GBS with an initial relative risk of 7.6 (95% CI 6.7–8.6) in the 6 weeks following vaccination. Any vaccine-related increase in GBS following modern influenza vaccines has been tiny, with the consensus of many robust studies being about one additional case per million vaccinations. The world is about to vaccinate at least 1 billion people. Within a population of 1 billion people, one would expect about 17 000 cases of GBS to occur sporadically per annum, of which 1962 would occur in any 6-week period. It is therefore inevitable that many thousands of sporadic cases of GBS caused by other factors will appear temporally associated with COVID-19 vaccination. But, as any statistician can confirm, this cannot be considered causal.

Household Transmission of SARS-CoV-2: A Systematic Review and Meta-analysis
A total of 54 relevant studies with 77 758 participants reporting household secondary transmission were identified. Estimated household secondary attack rate was 16.6% (95% CI, 14.0%-19.3%). Household secondary attack rates were increased from symptomatic index cases (18.0%; 95% CI, 14.2%-22.1%) than from asymptomatic index cases (0.7%; 95% CI, 0%-4.9%), to adult contacts (28.3%; 95% CI, 20.2%-37.1%) than to child contacts (16.8%; 95% CI, 12.3%-21.7%), to spouses (37.8%; 95% CI, 25.8%-50.5%) than to other family contacts (17.8%; 95% CI, 11.7%-24.8%), and in households with 1 contact (41.5%; 95% CI, 31.7%-51.7%) than in households with 3 or more contacts (22.8%; 95% CI, 13.6%-33.5%).

Inferring the effectiveness of government interventions against COVID-19
We gathered chronological data on the implementation of NPIs for several European, and other, countries between January and the end of May 2020. We estimate the effectiveness of NPIs, ranging from limiting gathering sizes, business closures, and closure of educational institutions to stay-at-home orders. Closing all educational institutions, limiting gatherings to 10 people or less, and closing face-to-face businesses each reduced transmission considerably. The additional effect of stay-at-home orders was comparatively small.

Fig. 2 NPI effectiveness under default model settings. Posterior percentage reductions in Rt with median, 50% and 95% prediction intervals shown. Prediction intervals reflect many sources of uncertainty, including NPI effectiveness varying by country and uncertainty in epidemiological parameters. A negative 1% reduction refers to a 1% increase in Rt. “Schools and universities closed” shows the joint effect of closing both schools and universities in conjunction; the individual effect of closing just one will be smaller (see text). Cumulative effects are shown for hierarchical NPIs (gathering bans and business closures) i.e., the result for “Most nonessential businesses closed” shows the cumulative effect of two NPIs with separate parameters and symbols—closing some (high-risk) businesses, and additionally closing most remaining (non-high-risk, but nonessential) businesses given that some businesses are already closed.

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