Take your doubts about the 4th dose of the Covid vaccine

Now all people over the age of 18 in the city of São Paulo can now take the fourth dose of the Covid vaccine.

Here’s what you need to know before getting vaccinated.

Can I take the fourth dose (second booster dose)? If you are over 18 years old, yes. The reinforcement for this age group was released on Tuesday (9). According to the São Paulo City Hall, 911,701 people are eligible.

Are there any restrictions? Yup. You must have taken the third dose (first additional dose) at least four months ago.

Where can I get the vaccine? Vaccination takes place at UBSs (Basic Health Units), AMAs (Outpatient Medical Assistance), AMA/Integrated UBS, at Health Centers, at SAEs (Specialized Care Service) and at megaposts.

The list of stations can be found on the Vacina Sampa page.

The population can also check the availability of vaccines by manufacturer, as well as the status of vaccination queues at stations in real time through the De Olho na Fila platform.

What vaccines are available for fourth dose? All Covid vaccines approved in Brazil (Pfizer, AstraZeneca, Janssen and Coronavac) can be used for the fourth dose.

Although São Paulo is using Coronavac, the Ministry of Health indicates for booster doses only the immunizers from Pfizer, AstraZeneca and Janssen.

I’ve heard that there are expired vaccines being used. It is true? Not exactly. A few months ago, Anvisa unanimously approved the extension of the validity of some batches of AstraZeneca vaccine.

It is worth mentioning that this is not surprising. Specialists already evaluated that vaccines against Covid had real expiration dates greater than those initially stated on the package inserts. To give you an idea, some of these immunizers officially expired just over four months after manufacturing. Meanwhile, traditional vaccines have maturities that reach up to three years.

Due to the urgency for application in real life, manufacturers ended up putting shorter expiration dates, but it was expected that, with time, expiration dates would increase.

Does the fourth dose have a greater risk of causing serious adverse reactions? In general, there is no evidence to indicate risks of different or more severe reactions at the fourth dose. In fact, reactions tend to be rarer with each dose of the vaccine.

When using a heterologous regimen (ie a different vaccine than those used in other applications), there are chances of reactions, but generally mild.

Adverse reactions to Covid vaccines are mild, usually pain at the injection site, feverish sensation, malaise, body pain and flu-like symptoms. This normally lasts up to 24 hours or a maximum of two days.

Other people will not feel any reaction at all.

Other less usual reactions can also occur in a small percentage of people. According to the Pfizer package insert, for example, 0.1% to 1% of those immunized may have insomnia, intense physical fatigue, night sweats or hives.

Very rarely there are serious adverse effects. Such cases are monitored by health authorities, who verify whether such cases are, in fact, related to the vaccine taken.

When I get the Covid vaccine, can I get others at the same time? He can.

Initially, the Ministry of Health indicated an interval of 14 days between the application of the Covid vaccine and others. The objective of the measure was to evaluate, with real-life information, the safety profile of immunizers used on a large scale. With the real-life data pooled together, the gap was no longer necessary.

Still in 2021, the ministry declared that the break was no longer necessary.

“Giving multiple vaccines in just one visit increases the chances of having a
updated vaccination card allowing to increase vaccination coverage, protect the population against
vaccine-preventable diseases and optimize the use of public resources”, states the technical note related to the administration of several vaccines at the same time.

According to the ministry, the ideal is that each vaccine is applied to a different muscle group. But, if this is not possible, the applications must, at least, respect the distance of 2.5 cm between them.