Why do I need two Covid-19 boosters after one J&J vaccine?

The National Institute for Communicable Diseases (NICD) says booster shots of the Covid-19 vaccine are effective in improving protection against the virus.

To boost the country’s vaccination drive, the health department is rolling out the second booster dose for recipients of the J&J vaccine.  

Vaccine boosters are recommended to increase antibody levels and T-cell responses to SARS-CoV-2.

The NICD said laboratory testing has shown that high antibody levels are more effective at neutralising variants of SARS-CoV-2. 

“Therefore booster vaccines are helpful to improve protection from infection, especially during the fourth wave which was predominantly due to the Omicron variant,” said the NICD.

Those who have received their initial single dose of the J&J vaccine are eligible for their first booster after 60 days. 

They can also get a second booster, 90 days after the first. 

Boosters can be mixed, which means people can choose between the J&J and the Pfizer booster, said the department. 

“Both the first and second booster doses may be homologous or heterologous.

“You are now able to get a mixture of the J&J and Pfizer vaccines against Covid-19. You just have to be fully vaccinated with the one, then ask for the other as a booster, after either 60 or 90 days, depending on which you got first.”

The institute said common side effects include tiredness, body aches and pains, low-grade fever, and pain at the injection site. 

“People who have a booster vaccine may experience these common side effects more frequently. These side effects resolve completely within 24-48 hours.

“Occasionally, very rare side effects such as myocarditis may occur slightly more frequently after a second (or booster) vaccine. If you have experienced any side effects after your first vaccine, you should report the side effect on the MedSafety app and discuss the need for a booster with your healthcare provider,” said the NICD.