Dr. Boarhead’s Summary of Global Updates on the 2019 Novel Coronavirus: 13th December 2020
1.
Nature Biomedical Engineering
:
Scientists reported an amplification-free nucleic acid immunoassay, implemented on a lateral flow strip, for the fluorescence detection of SARS-CoV-2 RNA in less than one hour. In a multi-hospital randomized double-blind trial involving 734 samples (593 throat swabs and 141 sputum) provided by 670 individuals, the assay achieved sensitivities of 100% and specificities of 99% for both types of samples.
<3 Dec.>
[key info]
Lateral flow testing is rapid and accurate.
https://www.nature.com/articles/s41551-020-00655-z
2.
Lancet
:
From 24 Mar. to 29 Sep., a total of 2,873,726 users living in England signed up to use the COVID Symptom Study app, of whom 2,842,732 (98.9%) provided valid age information and daily assessments. These users provided a total of 120,192,306 daily reports of their symptoms and recorded the results of 169,682 invited swab tests. On 28 Sep., an incidence of 15,841 daily cases, a prevalence of 0.53%, and an R(t) of 1.17 were estimated.
<3 Dec.>
[key info]
Self-reported data from an application can provide disease surveillance.
https://www.thelancet.com/journals/lanpub/article/PIIS2468-2667(20)30269-3/fulltext
3.
Nature Microbiology
:
An orally efficacious ribonucleoside analogue inhibitor of influenza viruses, MK-4482/EIDD-2801, was repurposed for use against SARS-CoV-2 and is currently in phase 2/3 clinical trials. Its efficacy to mitigate SARS-CoV-2 infection and block transmission was tested in the ferret model. Therapeutic treatment of infected animals with MK-4482/EIDD-2801 twice a day significantly reduced the SARS-CoV-2 load in the upper respiratory tract and completely suppressed spread to untreated contact animals.
<3 Dec.>
[key info]
MK-4482/EIDD-2801 may be a promising countermeasure against SARS-CoV-2.
https://www.nature.com/articles/s41564-020-00835-2
4.
Nature
:
In a study assessing the humoral and cellular immunity against SARS-CoV-2, researchers found that adoptive transfer of purified IgG from convalescent macaques protected naïve recipient rhesus macaques against SARS-CoV-2 challenge in a dose-dependent fashion. Depletion of CD8+ T cells in convalescent animals partially abrogated the protective efficacy of natural immunity against SARS-CoV-2 re-challenge, suggesting the importance of cellular immunity in the context of waning or sub-protective antibody titers.
<4 Dec.>
[key info]
Cellular immune responses may also contribute to protection if antibody responses are suboptimal.
https://www.nature.com/articles/s41586-020-03041-6
5.
Science Translational Medicine
:
Acute humoral responses to SARS-CoV-2 were measured in 159 patients, including the frequency of antibody-secreting cells and the presence of SARS-CoV-2-specific neutralizing antibodies in the serum, saliva, and broncho-alveolar fluid. In the early phase, IgA contributed to virus neutralization to a greater extent than IgG. Specific IgA serum concentrations decreased notably one month after symptom onset, but neutralizing IgA remained detectable in saliva for 49–73 days after symptom onset.
<7 Dec.>
[key info]
IgA dominates the early neutralizing antibody response to SARS-CoV-2.
https://stm.sciencemag.org/content/early/2020/12/04/scitranslmed.abd2223
6.
Journal of the American Medical Association
:
In England, a study accessing the risk of stillbirths during the COVID-19 pandemic has shown that between 1 Apr. and 30 Jun., there were 543 stillbirths, compared with 565 stillbirths for the same period in 2019. Within individual regions, the rate of stillbirth deliveries was not significantly higher in the lockdown period.
<7 Dec.>
[key info]
The pandemic did not cause more stillbirths in England.
https://jamanetwork.com/journals/jama/fullarticle/2774088
7.
Lancet
:
Countries have restricted international arrivals to delay the spread of SARS-CoV-2. In May, imported cases were likely to have accounted for a high proportion of total incidence in many countries, contributing more than 10% of total incidence in 102 of 136 countries when assuming no reduction in travel volumes and in 74 countries when assuming estimated travel volumes. Imported cases in Sep. would have accounted for no more than 10% of total incidence in 106 of 162 countries and less than 1% in 21 countries when assuming no reductions in travel volumes.
<7 Dec.>
[key info]
Restricted international arrivals may not result in reduced cases.
https://www.thelancet.com/journals/lanpub/article/PIIS2468-2667(20)30263-2/fulltext
8.
Lancet
:
11,636 participants were included in an interim primary efficacy analysis of the ChAdOx1 nCoV-19 vaccine. In participants who received two standard doses, vaccine efficacy was 62.1%, and in participants who received a low dose followed by a standard dose, efficacy was 90.0%. Overall vaccine efficacy across both groups was 70.4%. 21 days after the first dose, there were ten hospitalized cases, all in the control arm. Two were classified as severe COVID-19, and one of them died later.
<8 Dec.>
[key info]
ChAdOx1 nCoV-19 has an acceptable safety profile and has been found efficacious against COVID-19.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32661-1/fulltext
9.
New England Journal of Medicine
:
43,448 participants underwent randomization and received injections, 21,720 with BNT162b2 and 21,728 with the placebo. There were 8 cases with symptom onset at least 7 days after the second dose among participants assigned to receive BNT162b2 and 162 cases among those assigned to the placebo. Among 10 cases of severe COVID-19 with symptom onset after the first dose, only 1 was a BNT162b2 recipient.
<10 Dec.>
[key info]
BNT162b2 proves to be safe and effective.
https://www.nejm.org/doi/full/10.1056/NEJMoa2034577?query=featured_coronavirus
This is issue fifty
, edited on the basis of information from the official websites including but not limited to those of
The World Health Organization,
The European Centre for Disease Prevention and Control,
The Centers for Disease Control and Prevention of the United States of America, &
The Center for Infectious Disease Research and Policy of the University of Minnesota
and from the forums of FluTrackers.com.
This issue is edited by Alex Sun, Fred Wong, Dorothy Fang, and Dora Zhang under the supervision of Dr. Jason Chu and Conch Zhang.
2020 © The Chung Kwong Wui
