DUBLIN — Analysis of commercially available coronavirus antibody tests shows a “broad range of performance,” with patients suffering “severe disease” after infection later showing a more “readily detectable antibody response” compared to milder cases.
The research, published in the journal PLOS Pathogen on Thursday, was funded by Britain’s Department of Health and carried out by a team from institutions including Kings College London and the University of Amsterdam.
The team assessed 10 antibody test kits by “using blood from patients admitted to hospital with Covid-19 throughout the peak of the epidemic in London.”
The test kits “all gave the best results when used 20 days or more” after illness.
While almost 32 million cases of the virus have been reported worldwide, according to official statistics collated by Johns Hopkins University, the true extent of its spread remains unknown due to uncounted asymptomatic carriers and variations in virus testing regimes across countries and over time.
Antibody tests supplement testing for the virus itself as they “can determine whether someone has had the virus in the past,” the researchers said.
The utility of antibody testing was however limited by what the researchers labelled an “incomplete knowledge of the immunology” of the virus.
Official antibody test results have varied widely across countries.
Research published in Russia in May suggested 14 per cent of people had been infected, while India in July found 16 per cent had antibodies. Spain and Ireland registered around 5 per cent and 2 per cent respectively by August.Show