UAE: Recovered Covid patients may have immunity for 9 months

Dr Anthony Thomas, pathologist and director of Prime Healthcare Group’s diagnostic division, said that from the data they had gathered in the last nine months from Covid patients, the level and strength of antibodies vary from one person to another.

“We noticed that in some Covid patients, antibodies remained active for up to nine months after the infection, while in some, antibodies lasted for six to eight months. There were some exceptions and rare cases of re-infection of Covid-19, but then again the severity of the symptoms was much less compared to the previous time.”

Chances of re-infection were found in people with low immunity; those on treatment for chronic diseases like cancer; or taking immune suppressants for a disease, Dr Thomas said. “Even the elderly can be at a higher risk of getting infected again.”

A new study from the UK Biobank reveals similar results and states that people who have recovered from Covid-19 most likely have high levels of antibodies for six months or more. It also provides reassurance that reinfection soon after recovery should be rare. Under the research conducted across a segment of Covid patients in Britain, it was found that from among the 1,700 people who tested positive for a previous Covid-19 infection, 99 per cent had antibodies that lasted for three months and 88 per cent still had antibodies after six months.

At another UAE facility, internal medicine specialist Dr Mukesh Kumar Shewak also affirmed that Covid antibodies are seen to last for up to eight months.

“It all depends on the severity of the Covid-19 infection, if you have severe symptoms of the virus then the antibodies produced will be stronger and will last longer. Chances for re-infection as per the studies done here in the UAE show that are less than one per cent,” said Dr Shewak, who worked at the Covid ward of Canadian Specialist Hospital.

How antibodies work

Antibodies act one’s first line of defence against a virus. Here’s how they work as explained by Dr Anthony Thomas:

“When one contracts Covid, there are two types of antigens — that are the structural protein of the virus that enter our bodies. Our body then starts producing antibodies to fight it. The three kinds of antbodies produced by our body are – IgM, IgA and IgG.

“The IgM antibodies develop by fifth to seventh day after getting infected and it lasts only few days. The next type of antibodies that take over are IgA, which are mostly restricted to our mucosal system — oral, nasal, pharanx — where they form a protective cover and lasts for 10 to 15 days, after which the third and the strongest antibodies called IgG take over. This next wave of IgG antibodies develops after a longer time and lasts for months together that provides us long standing immunity.”

saman@khaleejtimes.com