Does the Covid-19 vaccine weaken your immune system?

Experts have allayed fears the Covid-19 vaccine weakens the immune system, saying it is able to protect you against other infections and is gearing up to fight future Covid-19 infection.

Chief executive of the British Society for Immunology, Dr Doug Brown, told Reuters: “The Covid-19 vaccines do not weaken your immune system’s ability to respond to other infections so getting your jab will not make you more susceptible to colds or flu.

“After Covid-19 vaccination, your immune system is just as able to fight off cold or flu viruses, and it will be better prepared to protect you against Covid-19.”

Head of the infectious diseases department at the University of Pretoria, Prof Veronica Ueckermann, told the Sunday Times your body may experience side-effects after getting the vaccine. However, this is not because the immune system is weak but because it is responding to the viral infection.

The first jab in a two-dose treatment “activates your immune system and immune cells are trained to identify and get rid of SARS-CoV-2 [the virus that causes Covid-19] without actually exposing you to this virus,” said Prof Hannelie Meyer, head of the SA Vaccination and Immunisation Centre (Savic) at Sefako Makgatho Health Sciences University, and Prof Rose Burnett, a scientific adviser at Savic

“However, such protection is not optimal after the first dose, hence the need for a second.

“When you get the second dose of the vaccine, you already have ready-made antibodies and primed T-cells that respond robustly to the spike proteins produced by the cells that have taken up the vaccine, which explains why some people experience a strong reaction.”

There are several different Covid-19 vaccines available around the world, two of which are used in SA,

The vaccines use different technology to help your body create a protein found on the virus and develop antibodies against future infection.

The World Health Organisation said vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body. Newer vaccines contain the blueprint for producing antigens rather than the antigen itself.

“Regardless of whether the vaccine is made up of the antigen itself or the blueprint so that the body will produce the antigen, this weakened version will not cause the disease in the person receiving the vaccine, but it will prompt their immune system to respond much as it would have on its first reaction to the actual pathogen.”

To date, 37.1-million doses have been administered in SA , with 9.1-million Johnson & Johnson and 28-million Pfizer jabs given.

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