With inputs from Dr Monica Vasudev

Florona, first case of double infection of Covid-19 and influenza

A case of “florona”, a double infection of Covid-19 and influenza at the same time has been reported in a pregnant woman who delivered a child at a hospital in Israel this week, in the 38th week of her pregnancy. This is the first such case in the world. According to reports, the woman was unvaccinated and has mild symptoms. Israel has recently approved the fourth booster dose for the vulnerable population in view of the Omicron cases... (Source: Wion, Dec. 31, 2021)

J&J Covid-19 booster dose improves protection against hospitalization

Preliminary results of the Sisonke 2 Study in South African health care workers show that a booster dose of the J&J Covid-19 vaccine, given 6-9 months after the initial single vaccination increased vaccine effectiveness against hospitalization from 63% to 84% and then 85%, 0-13 days, 14-27 days, and 1-2 months after the booster dose. The trial was conducted in November and December but participants were enrolled before the advent of the current Omicron wave in South Africa. The yet to be peer reviewed study is published on the preprint server medRxiv… (Source: medRxiv, Dec. 29, 2021)

SARS-CoV-2 can remain in the body for months

According to a preprint study (currently under review for publication in the journal Nature) by the National Institutes of Health, SARS-CoV-2 causes systemic infection as it is found to be is extensively distributed in the body, even among patients who died with asymptomatic to mild infection. Autopsies done on 44 Covid-19 patients showed viral RNA in multiple anatomic sites, including the heart and brain, for up to 230 days following the onset of symptoms… (Source: In Review, Dec. 20, 2021)

CDC reduces quarantine and isolation duration 

The CDC has reduced the isolation and quarantine duration for the public. People with Cvido-19 should isolate for 5 days and if they are asymptomatic or their symptoms are resolving (without fever for 24 hours), follow that by 5 days of wearing a mask when around others to minimize the risk of infecting people they encounter.

Unvaccinated persons or those who received their second mRNA dose six months back (or more than 2 months after the J&J vaccine) and are not yet boosted, should quarantine for 5 days followed by strict mask use for an additional 5 days. Alternatively, if a 5-day quarantine is not feasible, it is imperative that an exposed person wear a well-fitting mask at all times when around others for 10 days after exposure. Those who are boosted don’t need to quarantine after an exposure, but should wear a mask for 10 days after the exposure … (Source: CDC, Dec. 27, 2021)

T cell-mediated immunity may protect from Omicron

Results of a preprint study demonstrate that regardless of the large number of mutations in the new Omicron variant and its immune escape from neutralizing antibodies, the majority of T cell response, induced by vaccination or natural infection, cross-recognises the variant. Researchers examined unvaccinated convalescent COVID-19 patients including persons who had taken the Pfizer-BioNTech and the Johnson and Johnson vaccines. They concluded that “well-preserved T cell immunity to Omicron is likely to contribute to protection from severe Covid-19”…(Source: medRxiv, Dec. 28, 2021).

British data shows that booster protection may decline in 10 weeks

Data from Britain shows that booster protection against symptomatic Covid-19 due to the Omicron variant may decrease within 10 weeks. Among persons who received AstraZeneca as the primary vaccination, the Pfizer booster was 35% effective after 10 weeks, while the effectiveness of Moderna was 45%. Persons who had taken Pfizer vaccine initially followed by Pfizer booster saw a decline in vaccine effectiveness to 45% from 70%, after 10 weeks. Those who received an initial two-dose series of the Pfizer vaccine and then a Moderna booster seemed to have 75% effectiveness up to 9 weeks … (Source: Medscape, Dec. 27, 2021)