If someone had COVID-19, when should they get vaccinated?

Worldwide, more than450 million doses of vaccines for COVID-19. In most countries, priority access is being given to frontline healthcare workers, as well as older adults. Israel leads the immunization campaign, although it also asks its citizens not to let their guard down and continue with hygiene and physical distancing measures. In Ecuador, more than 140,000 people have been vaccinated, according to government data.

As COVID-19 is a new disease, many aspects about it are still unknown. For example, scientists are still wondering how long the antibodies the body generates to fight infection, or the role played by T cells -apparently longer lasting than antibodies-, to destroy SARS-CoV-2. Regarding the vaccines, which were developed in record time, their effectiveness is still being analyzed.

At the beginning of the global health emergency, some specialists expected that those who already had COVID-19 would automatically be immunized for life against the infection. However, as the months passed, it was found that some patients can become infected again. Hence, organisms such asWorld Health Organization (WHO)They have asked not to relax and continue wearing masks, apply hand washing as well as physical distancing, or avoid crowds.

Apart from reinfections, the problem of variants arises. Since it emerged in late 2019 in China, SARS-CoV-2 - like all viruses - has mutated, giving rise to new variants and strains. In this way, in the last months of 2020, the appearance of new variants was reported in the United Kingdom, South Africa and Brazil. Apparently these variations are more contagious and lethal than the original coronavirus that emerged in the Asian nation. This situation tests the effectiveness of vaccines, although some pharmaceutical companies have advanced that their products are effective for immunization.

Time to get vaccinated

CurrentlyIt is recommended that people who have already had COVID-19 wait up to six months to get the vaccine, so that more people - especially at risk - who do not have antibodies against the virus can be in better condition if they become infected. However, the spread of new variants could change this plan.

According to a group of immunization experts that advises the WHO, the initial plan can be continued if the place where those who had the disease live does not circulate any of the variants of the original coronavirus, otherwise they should not wait, details the agencyEfe.

“We recommend as an act of solidarity in the face of the vaccine shortage situation to wait six months (to get vaccinated) if a person has been infected, butIn countries where variants of concern circulate, it is recommended not to wait"said the president of the team of scientists, Alejandro Cravioto.

He explained that in those places those who have had COVID-19 should not wait more than one or two weeks to be vaccinated if they have the possibility.

This position is based on situations that have been observed, such as that of the Manaus region in Brazil, where the circulation of a variant has caused aconsiderable number of reinfections, he recalled.

The group of experts indicated that in these contexts “there is no need to wait” because the vaccine can boost immunity and offer some protection against any of the most worrying variants, which are the ones that were first identified in Brazil, the United Kingdom and South Africa.

The US Centers for Disease Control and Prevention (CDC) also recommends getting vaccinated “whether you have had COVID-19 or not.” It suggests, in any case, that if the patient received treatment for COVID-19 with monoclonal antibodies or convalescent plasma, wait 90 days to get vaccinated.

Epidemiologist Francisco Andino suggests that every patient who has overcome COVID-19 should consult their doctor before receiving the vaccine. "In any case, if someone wants to get vaccinated and has had COVID, the first thing they would have to do is analyze (with their doctor) how their immune response to COVID is," he pointed out.

A single dose

Andino also indicated that patients who have overcome COVID-19 could even only receive a single dose of the vaccine, in cases where it is a two-dose vaccine.

According to research led by scientists at the Icahn School of Medicine at Mount Sinai in New York, a person who has previously had COVID-19 and who receives a single dose of the Pfizer or Moderna vaccine is equally or better protected than someone who has never had the disease and has received two doses.

The team examined blood samples from 110 people, 67 of whom had not previously been infected and another 43 who had. All participants received thePfizer or Moderna vaccine, both based on new RNA (messenger ribonucleic acid) technology.

The scientists observed that participants who had already contracted the coronavirus before receiving the first dose “rapidly developed uniform and high antibody titers days after vaccination.”

These “titers” refer to the concentration in the blood.

The scientists took several samples from the participants and observed that in the days following the first vaccine, the antibody levels of those who had previously had the infection were 10 to 45 times higher than in those who had not had it.

When both groups received their second dose, antibody levels among those previously infected were stillsix times higher than those who had not been infected before.

But “increasing antibody titers were not observed in COVID-19 survivors who received the second dose of the vaccine,” the scientists wrote, noting that thisbooster dose was shown to be of limited benefit for previously infected people. (YO)