HEALTH experts in York are calling on the Government to offer antibody tests more widely rather than to just those testing positive.

YorkTest, the home-to-laboratory test specialist, has analysed the first study of Covid-19 antibody levels using home testing kits, and say the results support an argument for more people to be tested.

The trial included people who have received a single dose, those who have had two and people who have had Covid-19 and not been vaccinated.

It found that those who have had Covid-19 and recovered have more antibodies than those who have only had one jab, but far less than two jabs.

Those who have had two doses of a vaccine experienced a 4,500 per cent average increase in antibody levels compared to people who have only had a single dose.

Participants who have recovered from Covid-19, but not been vaccinated, had higher levels of antibodies on average than those who have only received a single vaccine.

Dr Gill Hart, scientific director at YorkTest, said the results from the 'relatively small trial' were conclusive.

"Put simply, the most important thing for public health is to ensure that as many people as possible have two vaccinations."

However, she cautioned: “Although results of our initial trials show that immunity is reaching its highest point three to six months after a second vaccine dose, there is some suggestion that antibody levels may start to decrease from that point.

“Our study is ongoing and the Government has already announced plans to provide antibody tests to those testing positive following a PCR test.

"However, our results show there’s an argument for antibody testing to be rolled out more widely. People need to be mindful of their own antibody levels so they can make informed decisions about their day-to-day lives.

"Granted, we have heard that a booster programme is coming but we still don’t know when that will be and who will be included.

“Our trial continues and we have now entered the crucial phase where we start monitoring antibody levels six-nine months after a second vaccine dose.”

The British Medical Journal has defined a high level of Covid-19 antibody protection asbeing over 250 U/ml.

The YorkTest trial found that after one vaccine dose, average antibody levels were 24 U/ml, and after two doses, levels were 1,084 U/ml, among people who had not had Covid-19.

For those who had recovered from Covid-19 but not been vaccinated, average antibody levels were 95 U/ml.

The average level of antibodies to Covid-19 was 997 U/ml, up to 100 days after the second vaccine dose, which increases by 25 per cent to about 1,242 U/ml between 100 and 171 days.

This, together with data showing reducing antibodies, suggests peak protection three to six months after receiving a second vaccine.

From limited initial trial data, those people who have both had Covid-19 and are also double vaccinated recorded the highest levels of antibody protection, over 2,500 U/ml.