People who generate antibodies after being infected with COVID-19 are likely to be immune from the virus for up to half a year, a new study has confirmed.
Scientists from the University of Michigan examined more than 100 participants who had been infected with the coronavirus for up to six months after they first tested positive with the disease.
Most of the participants only suffered with minor symptoms, such as headaches, temperature chills and changes to taste and smell. However, three had severe COVID-19 and were admitted to hospital to receive medical treatment.
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Apart from one individual, each participant had antibodies in their system at their check-up examination and spike and nucleocapsid antibodies were found in 90% of the group.
Senior author Dr Professor Charles Schuler said: “Previously, there was a lot of concern that only those with severe COVID-19 produced strong antibody responses to infection.
“We’re showing that people with mild bouts of COVID-19 did really well after their infection, made antibodies, and kept them.”
Participants in the trial were made up of healthcare professionals and other individuals who have been frequently exposed to COVID-19.
Throughout the initial stages of the assessment, no participants who generated antibodies were re-infected, whereas re-infection occurred in 15 people who did not produce antibodies.
The team of academics also discovered that the antibodies’ capability to counteract the virus did not substantially alter between the two visits, which were three months and six months after the initial infection.
Researcher Dr James Baker said: “While some studies have suggested antibodies against COVID-19 wane over time, these findings provide strong prospective evidence for longer-term immunity for those who produce an immune response to mild infection.
“To our knowledge, this is the first prospective study that demonstrates such a risk reduction for clinical reinfection in this specific type of population.”
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Previous analysis has identified that individuals who have not been double jabbed are up to two times more at risk of being infected with COVID-19 again.
“These results are encouraging for those who have already run the gauntlet of COVID-19 infection, however, I do not recommend citing this study as a reason not to be vaccinated for those never previously infected,” said Dr Professor Schuler.
He added: “Vaccination decreases infectiousness, the risk of hospitalisation and deaths from COVID-19, without having the actual infection.
“Achieving natural immunity by deferring vaccination in favour of infection is not worth going through the discomfort, risk to yourself and risk to others.”
The entire research study can now be accessed in the journal ‘Microbiology Spectrum’.