Immunity to Covid-19 in recovered patients may only last a few months, according to new research.
In what is believed to be the first longitudinal study of its kind, researchers at King’s College London looked into the immune response of 90 patients and healthcare workers at Guy’s and St Thomas’ NHS Trust.
While the analysis revealed a ‘potent’ level of antibodies in 60% of participants at the peak of their battle with coronavirus, sequential blood tests showed that only 17% retained that same level of potency three months later.
According to the research, which has not yet been peer-reviewed, immunity antibodies decrease significantly in the three months following infection, suggesting patients could be susceptible to reinfection year after year – similar to the common cold.
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Researchers looked into the immune response of 90 patients and healthcare workers
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Lead author Dr Katie Doores told the Guardian: ‘People are producing a reasonable antibody response to the virus, but it’s waning over a short period of time and depending on how high your peak is, that determines how long the antibodies are staying.’
The research indicated that antibodies rose higher and lasted longer among patients with severe cases.
That may be because they have more virus and produce more antibodies to fight off the infection.
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The study indicated that antibodies rose higher and lasted longer among patients with severe cases
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The research also indicated that patients could be susceptible to reinfection year after year
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The results would appear to undermine any idea of pursuing ‘herd immunity’. They would also have implications for the development of a vaccine as any protection offered may similarly wane in two to three months, meaning one shot may not be enough.
Dr Doores said infection is typically the best-case scenario to trigger an antibody response and if infection gives you antibodies which diminish in two to three months, ‘the vaccine will potentially do the same thing’.
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Experts say the virus which causes Covid-19 may be falling into the same group as the other coronaviruses currently in circulation, including the common cold
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There are currently four other types of coronavirus in circulation among the human population – including the common cold.
Professor Stuart Neil, who co-authored the study, told the Guardian that ‘one thing we know about these coronaviruses is that people can get reinfected fairly often’.
He added: ‘What that must mean is that the protective immunity people generate doesn’t last very long. It looks like Sars-Cov-2, the virus that causes Covid-19, might be falling into that pattern as well.’
