Who will be tested for antibodies – and are we going to get immunity passports?
Q. The health service is to start testing people next month for antibodies to see if they have had the coronavirus. Will that result in people with antibodies getting immunity passports? A. No. Screening involves a blood test for antibodies to find who has had the coronavirus and recovered.
Two or three weeks after the infection takes place, the immune system builds antibody responses against the virus, which can be detected by a lab test. The aim is to get a better measure of the true rate of infection here.
The idea of immunity passports – certificates people would get on the assumption they would be immune to reinfection – was first mooted in Germany.
But that seems to have been parked for now because it is too early to say if someone is protected against reinfection.
Q. Will these blood tests be made available to everyone? A. They will be directed at a few thousand people at first, from a county with high prevalence and one with low prevalence which are representative of the wider population in categories such as age and gender.
There are more than 23,400 laboratory confirmed cases of the virus here to date but the real numbers of people infected are likely to be higher. Prof Philip Nolan of Maynooth University estimates it could be slightly more than double that figure.
Q. Other countries are also doing this antibody testing. What have they found?
A. Results from antibody tests in Gangelt, in the Heinsberg district of Germany, suggest the outbreak is much greater than official figures show.
The preliminary results suggest 15pc of Gangelt, with a population of 13,000, had the virus at some stage. Antibody testing in New York city, which was badly hit, suggested the true rate of infection was as high as 21.2pc. Some 17pc of people in London and 5pc of the population in the rest of England tested positive for coronavirus antibodies, UK Health Secretary Matt Hancock said yesterday.
Some scientists here have speculated around 6pc of the population may have had the infection because so many had little or no symptoms.
Q. When will people who have developed antibodies know if they are protected from reinfection?
A. There are a lot of studies under way across the world looking at this. Obviously, if a substantial number of the population knew they would have immunity for a year or even two it would be a major boost for healthcare staff and the wider workforce. The World Health Organisation (WHO), however, says there is no evidence yet that people who have recovered from coronavirus and have antibodies are protected against a second infection.
The WHO said relying on antibodies at this stage of the pandemic could increase the risk of spreading the virus.
The Health Protection Surveillance Centre here states that a person may be immune from reinfection for the first few months.
Q. Will the information which is gathered from antibody testing here be of value in exiting lockdown? A. If it is found that a high percentage of the population here has been infected, it may allow for more risks to be taken. More is learned about the virus and there may be more clarity about who is immune. New revelations about the virus in relation to symptoms, its transmission and impact on victims emerge every week.
Q. Sweden is controversially aiming for herd immunity – is it working?
A. Herd immunity involves a level of the disease of around 80pc in the population to stop the spread of the virus. It has no lockdown and it’s too early to say if it will work. The price is the highest death rate in Europe.