Antibody tests work but not on those under the age of 40

TESTS to determine if someone has recovered from coronavirus may not be useful because younger people do not produce sufficient quantities of antibodies to be detected, early research suggests.

It was hoped that the tests could help kick-start the economy by allowing those who are immune out of lockdown. But supplies from China have so far failed to pass sensitivity and specificity tests.

Prof Karol Sikora, a private oncologist who validated a kit using samples from staff at his clinics, found the results came back negative for under-40s who had recovered from the virus.

He said: “I think the antibody tests do work, but young people just don’t seem to have the antibodies, which suggests they are using other mechanisms to fight off the virus.

“We’re not picking it up in young people, so politicians may not be able to issue certificates of immunity.”

Prof Sikora, who is also Dean of Medicine at the University of Buckingham, believes that young people may fight off the disease using “natural killer cells” which “gobble up” the virus so antibodies are never needed.

“I don’t think it will be a good tool for unleashing lockdown,” he added.

He has written to the Government with his findings and is awaiting a response.

Meanwhile, a team at Fudan University

‘We’re not picking up antibodies in the young so we may not be able to issue certificates of immunity’

in China also found that recovered virus patients in the 60 to 85 age group displayed more than three times the amount of antibodies as people in the 15-39 age group.

The findings are in line with suspicions that the virus could be deadlier to older people because it triggers an extreme immune response.

Their research was based on the analysis of 175 blood samples from patients discharged from the Shanghai Public Health Clinical Centre.