How accurate are Antibody tests?

Antibody tests have not proved to be as reliable.

Health Secretary Matt Hancock said that 15 of the most promising antibody tests had been tested, but none was good enough.

Prof John Newton, who is overseeing testing, told The Times that tests bought from China had been able to identify antibodies in patients who had been seriously ill with coronavirus, but didn't pick up the milder cases.

Antibody (Serology) blood test which looking at immune response specifically to the virus. Looks for both short term (IgM) and long-term (IgG) antibodies. May not show up as positive in the first few days of having the illness so if tested too early you may get a false result. Most tests are accurate after day 7 of having symptoms. The IgG antibody is likely to remain positive for at least a few months.

Why is testing important?

There are two main reasons for testing people – to diagnose them individually, and to work out how far the virus has spread.

Having this second piece of information could help the health service plan for extra demand, including on intensive care units.

Testing could also inform decisions around social distancing measures. For example, if large numbers of people were found to have already been infected, then a lockdown might become less necessary.

And not testing more widely means many people might be self-isolating for no reason, including NHS workers.

Can I get tested?

Testing is not yet available for most people. At the moment, most tests are reserved for seriously ill patients in hospital. It means the majority of people who have symptoms can't find out if they are currently infected with coronavirus.

Source: https://www.bbc.co.uk/news/health-51943612