A possible limitation is that mostly young children were studied.
Over half were aged <6 years, and 8 of the 12 children (67%) with long COVID were aged <3 years. As such, it may not be representative of all children.
Other studies have reported a longer duration of symptoms.
However, the proportion of children with long COVID in this study (8%) is consistent with data reported by the Office for National Statistics in the UK.
In the ONS data, 7-8% of children and adolescents reported symptoms lasting at least 12 weeks.
This article contains a number of inaccuracies, @liammannix. The results of the REACT-1 study in England (and many others) are indisputable: children are frequently infected with SARS-CoV-2.
Anyone who says otherwise at this point is either ignorant, or has an agenda.
Study of 25,661 UK healthcare workers (including 8,278 with past COVID-19), showing past infection offers 84% protection against reinfection (93% for symptomatic disease) over 1-7 months. The emergence of the UK variant didn’t make reinfection more likely. thelancet.com/journals/lance…
During the study, participants had a PCR test every 2 weeks, and an antibody test every 4 weeks, so we can be reasonably sure the majority of cases would have been detected.
There were 1,704 infections in people who hadn’t previously had COVID-19 (of which 17% were asymptomatic), and 2 probable and 153 possible reinfections (1.9%), of which 49% were asymptomatic.
Study of the Pfizer-BNT vaccine in 100 nursing home residents (64 with past COVID-19) & 15 healthcare workers.
A good antibody response was detected in 97% with past COVID-19, 93% of healthcare workers, but only 61% of residents who’d never been infected. academic.oup.com/cid/advance-ar…
A similar pattern was found with regard to cellular immunity.
A good response was found in 97% of residents with past COVID-19, and in 87% of healthcare workers, but only 48% of residents who’d never been infected.
This study was done 4 weeks after the first vaccine dose.
It’s unclear if the results indicate that older people may take longer to have a good response to the vaccine, or if it is less effective in older people.
If the latter, attaining herd immunity becomes more important.
(1/12) The Brazilian #COVID19 variant is up to 2 times more transmissible, more likely to cause serious illness in young people, and may evade immunity.
Worryingly, it’s starting to spread rapidly in British Columbia, Canada. 🇨🇦
A thread summarising the latest evidence. 🧵
(2/12) Previous research suggested the variant was 40 to 120% more transmissible, and may be able to reinfect people more easily.
Mortality appeared 10 to 80% higher, although it was unclear if this reflected hospitals being overwhelmed with cases.
However, vaccines have better efficacy against severe disease than mild-to-moderate disease.
It’s therefore likely that efficacy against severe disease will be largely preserved, but we may see reduced protection with regard to transmission.
There is also the potential for reinfections to be more common with this variant, particularly for people who had only very mild COVID-19, and did not develop much in the way of neutralising antibodies.
➡️ 91% (95% CI 89-93%) efficacy against symptomatic infection.
➡️ 100% (88-100%) efficacy against severe disease as per the CDC definition (based on 32 cases); 95% (71-99%) efficacy as per FDA definition (22 cases, 1 in vaccine group).
Additionally, Pfizer also reported data from South Africa, in which 800 people received the vaccine.
Nine cases were detected in the placebo group, 6 of which were the South African variant.
No cases were detected in the vaccine group.
This provides tentative evidence that the Pfizer vaccine may be effective against the South African variant, although the confidence interval is wide (53-100%).