Antibodies against the COVID-19 virus are not likely to last for long, according to the latest findings from British researchers seeking to establish the prospects of long term immunity.
Just 17% of patients maintained a potent antibody response three months after contracting the virus, according to research at King's College, London.
The researchers have been studying 90 patients and staff at Guy's and St Thomas' NHS Foundation Trust, according to media reports. They found that 60% showed a "potent" response at the height of their illness – but that antibody levels then fell by as much as 23 times in the subsequent months.
The study is awaiting peer review and publication. The findings echo those of a major study in Spain, reported last week, showing little evidence of "herd immunity" developing in the population of a country that suffered badly from the virus.
Researcher Dr Katie Doores said: “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 around."
The findings raise concerns about the long term impact of vaccines and other antibody treatments. A new antibody treatment was announced today by a pharmaceutical company.
Dr Doores said: “Infection tends to give you the best case scenario for an antibody response, so if your infection is giving you antibody levels that wane in two to three months, the vaccine will potentially do the same thing.
“People may need boosting and one shot might not be sufficient.”
Fellow researcher Professor Stuart Neil compared the findings with knowledge of the common coronaviruses that cause the common cold – and can reinfect frequently.
He said: "It looks like Sars-Cov-2, the virus that causes COVID-19, might be falling into that pattern as well.”
Virologist Professor Jonathan Heeney, from Cambridge University, said: “Most importantly, it puts another nail in the coffin of the dangerous concept of herd immunity.
“I cannot underscore how important it is that the public understands that getting infected by this virus is not a good thing. Some of the public, especially the youth, have become somewhat cavalier about getting infected, thinking that they would contribute to herd immunity. Not only will they place themselves at risk, and others, by getting infected, and losing immunity, they may even put themselves at greater risk of more severe lung disease if they get infected again in the years to come.”
Vaccine immunity blood test 
