Experts are now warning of the risk of Covid-19 infection even after the vaccine has been administered. The Centers for Disease Control and Prevention noted that during trials, the vaccines were shown to be only about 95% effective — meaning that some vaccinated people were still infected.

In line with recent reports, The Centers for Disease Control and Prevention opined that a very viable reason for the ineffectiveness of vaccines is the delay in building immunity.

 The two authorized coronavirus vaccines both require two doses, given several weeks apart, to train the body’s immune system and because it takes time for vaccines to build up immunity, if a vaccinated person is exposed to coronavirus right after, there won’t be time for the body to develop its defences.

Researchers also claim that protection provided by vaccines can fade over time, and some vaccines require top-up shots years later.

There is also the possibility that the novel coronavirus might mutate in a way that makes the vaccines less effective. Influenza virus strains mutate constantly and that’s one reason people need fresh flu vaccines every year.

However, doctors hope coronavirus won’t mutate as the flu does. In the case that it happens, the technology used to make the new coronavirus vaccines is designed to be easily adapted. It should take far less time to update the Moderna and Pfizer vaccines than it takes to make new flu vaccines.

In addition, health officials are cautioning people not to dump the face masks and social distancing behaviour just because they’ve been vaccinated.

This is because even people who are immune to the virus might be exposed to it and transmit it to others.