TESTING TIME
Coronavirus antibody test is nearly ready
Prime Minister Boris Johnson announced on 24 March that the government had ordered 3.5 million antibody test kits, which are able to identify in 10 minutes whether someone has had the COVID-19 infection. The kits can be used at home, involving just a finger prick
to produce a blood sample that is then tested for immune cells specific to the coronavirus.
A positive result on the test would mean that a person had successfully fought off the
SARS-CoV-2 virus and would have some immunity against future infection – though for how long that immunity would last is still unknown. For some viruses, such as smallpox or polio, one instance of infection is enough to give a person lifetime immunity. Others, such as norovirus, result in immunity against re-infection for up to two years, and for common colds, the body’s immunity can fade after just months. The antibody tests bought by the government won’t detect a current infection, but they’ll look for a type of immune cell – an antibody – that the body creates to tackle new infections. An antibody is produced by the body as part of an immune response and is specific to fighting a particular pathogen. It is thought that, once a person with coronavirus antibodies has been identified, their blood plasma could be used as a treatment for others infected with the virus.
As soon as the antibody tests have been validated, it is likely that they will be distributed for use first by key workers, before being made available to the wider public. “[The tests] will tell us who among individuals in our NHS and other essential workforces are immune to the virus and, therefore, safe to return to their vital work,” said David Wraith, director of the Institute of Immunology and Immunotherapy at the University of Birmingham. Following that, the tests could be given to people who are particularly vulnerable, said Paul Hunter, a professor of health protection at the University of 'ast Anglia. If they were immune, they could relax the measures at which they are self-isolating. -nowing who is immune will help those people stop worrying whether or not they are putting themselves or their families at risk, Hunter said.
These tests will also be of use when a vaccine first becomes available, as it will
initially be in short supply. “An antibody test would allow the vaccine be used just for people who are not already immune,”
said Hunter.