Boosting the vaccine against covid increases protection and may contain high cases

Despite the increase in Kovid-19 cases, the refresher dose remains low. However, experts argue that additional doses can help reduce transmission of the new wave and strengthen the body’s defenses against the virus.

The InfoGripe bulletin, published on November 23 by the Oswaldo Cruz Foundation (Fiocruz), pointed to an increase in serious Covid-19 patient cases. In addition, omicron sub-variants that can increase transmission, such as BN.1 and BQ.1, have been identified across the country.

The emergence of new strains is linked to increased circulation of the virus, according to Carla Kobayashi, an infection specialist at Sírio-Libanês Hospital. “The more people infected, the greater the likelihood of mutations and variants,” she said in an interview with She. Technology World🇧🇷

Kobayashi says booster vaccines can help control the new wave by reducing transmission. But the total number of people vaccinated with the booster scheme remains low, according to data released by the Ministry of Health this month: There are only 37.8 million people vaccinated with the second booster dose, compared to the nearly 168 million who received either two doses or a single dose. dose. .

Why booster vaccines may contain covid-19

Vaccines protect against threats by activating the body’s defenses. As Ingrid Cotta, an infection specialist from Beneficência Portuguesa de São Paulo (BP), explains, the immune system creates antibodies to fight the disease-causing agent after contact with the vaccine.

A memory is created that helps the body protect itself in case of contact with the virus not only now but also in the future. “This will trigger a faster and more robust response,” says Cotta.

However, vaccine-induced immunity tends to decline some time after vaccination, in a natural antibody process. According to Cotta, this is where additional doses come into play: as a “reminder” of immunological memory, it prepares the body to fight the threat again.

A survey by Fiocruz Minas showed the effectiveness of the vaccine in protecting against Covid-19. According to the study, only 17% of those vaccinated with CoronaVac developed antibodies against omicron within 30 days of the second dose. With the addition of Pfizer, this number increased to 77%. Fiocruz points out that it is more effective because it is a different vaccine than the one used in the first doses.

The additional dose also helps protect against variants of the virus, its mutations as it becomes more resistant. The new strains can evade the immune defense created by the first vaccine, and the booster helps keep antibodies active as well as avoiding severe forms of covid-19.

Cotta claims this already occurs in other illnesses, such as the flu. According to the infection expert, the Brazilian flu vaccine is based on the strain that circulates in Europe and can be brought here.

As with the flu, vaccines for different variants of Covid-19 should emerge, such as the Pfizer vaccine approved by Anvisa last Tuesday (22). The new vaccine, not yet implemented in the country, is an updated version that protects against omicron and its sub-variants.

Although the new campaign has not started, experts recommend that the booster program should be complemented with existing vaccines and maintenance measures should be continued to prevent the spread of the virus. Avoiding piles, wearing a mask, and sanitizing your hands are still recommended.

Following the increase in cases, municipalities and states decided to roll back mandatory preventive measures, such as the use of masks on public transport.

Infection expert Ingrid Cotta remembers that while life has already returned to normal, the pandemic is not over yet, as the World Health Organization (WHO) has warned. According to him, the scenario shows that vaccination campaigns against covid-19 will continue with no end in sight.