The risk of being contaminated with SARS-CoV-2, the virus that causes COVID-19, is considerably diminished for up to 10 months following the primary infection with the virus, in accordance to a study.
The analysis, revealed within the journal Lancet Healthy Longevity on Tuesday, checked out charges of COVID-19 infections between October lat years, and February this 12 months amongst over 2,000 care house residents and employees in England.
The researchers from the University College London (UCL) within the UK in contrast individuals who had proof of a earlier infection up to 10 months earlier, as decided by antibody testing, with those that had not been beforehand contaminated.
They discovered that residents with a earlier infection had been 85 % much less possible to be contaminated throughout this four-month interval than those that had by no means been contaminated.
Staff members with previous infection had been 60 % much less possible to be contaminated than those that had not had the infection earlier than.
The researchers mentioned this confirmed sturdy safety in each teams, however cautioned that the 2 percentages will not be immediately comparable.
This is as a result of the employees could have accessed testing outdoors the care house, main to constructive checks not being included within the study, they mentioned.
“It’s really good news that natural infection protects against reinfection in this time period. The risk of being infected twice appears to be very low,” mentioned study lead writer Maria Krutikov, from UCL Institute of Health Informatics.
“The fact that prior COVID-19 infection gives a high level of protection to care home residents is also reassuring, given past concerns that these individuals might have less robust immune responses associated with increasing age,” Ms. Krutikov mentioned.
For the study, 682 residents, with a median age of 86, and 1,429 employees in 100 care houses underwent antibody blood checks in June and July final 12 months following the primary wave of COVID-19.
About a 3rd examined constructive for antibodies, suggesting that they had beforehand been contaminated.
(*10*) then analysed the outcomes of individuals’ PCR checks, beginning roughly 90 days after the blood samples had been taken to make sure the checks didn’t decide up the preliminary infection.
PCR checks had been taken as soon as every week for employees, and as soon as a month for residents, with additional testing within the occasion of an outbreak.
Positive check outcomes had been solely included in the event that they had been greater than 90 days aside to make it possible for the identical infection was not included greater than as soon as.
The variety of employees and residents who had been reinfected between October and February was very small.
Based on the antibody check outcomes, out of the 634 individuals who had been beforehand contaminated, reinfections occurred in solely 4 residents and 10 members of employees.
Among the 1,477 individuals who had by no means been contaminated, constructive PCR checks occurred in 93 residents and 111 employees.
“This was a unique opportunity to look at the protective effect of natural infection in this cohort ahead of the roll-out of vaccination,” mentioned senior study writer Laura Shallcross, from UCL Institute of Health Informatics.
