How Do Booster Doses Of Covid-19 Vaccine Work?


Covid-19: On Tuesday (16), the Ministry of Health announced the release of booster doses of the vaccine against covid-19, a disease caused by the SARS-CoV-2 coronavirus, for all people over 18 in Brazil.

The additional dose can be received five months after the end of the first vaccination cycle (with the second dose of an immunizer). Until then, only a few groups received the boost: older people, people with compromised immune systems and health professionals. The five-month break is now valid for all groups.

According to the ministry, the new guidance is based on scientific research that indicates a drop in the immune response from the fifth month after the second dose. The phenomenon was expected by scientists, and it happens with other types of vaccine as well.

With the additional dose, studies show, protection against the disease grows—becoming greater than the protection obtained by the initial two doses.

Some states, such as São Paulo, have already started to apply the reinforcement.

The additional dose is seen with excitement by some experts, as it could increase protection and prevent a new wave of covid-19 in the country if distributed in time. Other infectious diseases, however, claim that government efforts should be focused on expanding the number of Brazilians fully vaccinated before expanding booster doses.

Countries in Europe, which are experiencing a high in cases of the disease, are already betting on the reinforcement to fight a new wave of covid. The United States extended the reinforcement to the entire adult population on Friday (19).

The Ministry of Health should also publish guidelines on boosting for those who took the Janssen vaccine (single dose) in the coming days.

How long will we need the masks?

It will take some time before the population can be safe to go everywhere without masks. A simple and non-invasive preventive measure, the use of a mask against respiratory infections has been supported by several scientific studies conducted over at least a century. This week, our columnist Bernardo Almeida, infectious disease physician and chief medical officer of health tech Hilab, further explained the use of this protection and why we still need it.