Although the vaccine against COVID-19 is not yet available to the majority of the population, we would like to answer some of the most frequently-asked questions according to current evidence and knowledge.
Is the vaccine safe?
As is the case with other medication, approval of all vaccines against COVID-19, its effectiveness, safety and quality have been guaranteed through clinical trials and a rigorous evaluation by the European Medicines Agency. Clinical trials of vaccines against COVID-19 were conducted in accordance with the standard procedures for testing any vaccine.
Tens of thousands of volunteers were vaccinated and compared with the identical number of volunteers that were not vaccinated to identify any adverse effects. The period of time during which the people that had received the vaccine were monitored after taking the second dose of the vaccine exceeded eight weeks. This is the period during which common adverse effects might appear after taking a vaccine. No adverse or severe effects were observed that might jeopardise the safety of the vaccines.
As with any medicine, trials cannot, however, exclude very rare adverse effects, which might only be detectable when a vaccine is given to millions of people.
IS THE VACCINE EFFECTIVE?
So far, there is one vaccine approved by the European Commission: the Comirnaty vaccine (from BioNTech/Pfizer). The main clinical trial that supported the authorisation to place this vaccine on the market involved a total of about 44,000 people and demonstrated that the vaccine has a 95% effectiveness.
This trial demonstrated that Comirnaty was effective in preventing COVID-19 in people over 16 years of age. It also demonstrated about 95% effectiveness in people at risk for severe COVID-19 disease, including those with asthma, chronic lung disease, diabetes, high blood pressure or body mass index ≥ 30 kg/m2.
WILL THE VACCINE PROTECT ME?
Yes. Being vaccinated against COVID-19 allows us to protect ourselves individually from the disease and its complications, as well as contributing to the protection of public health, through group immunity.
Although very effective, vaccines do not completely prevent the risk of infection. However, the few people who were vaccinated and have been infected have generally developed mild forms of COVID-19.
WHAT ARE THE SIDE EFFECTS OF THE VACCINE?
As with any other medication, the vaccine against COVID-19 can also have adverse reactions. Most of them are mild and short-term and not everyone will experience them.
All vaccines stimulate our defences, which can cause mild and short-lived side effects. Some individuals vaccinated against COVID-19 in the clinical trials reported having felt: pain with the injection; fatigue; headache; muscular aches; joint pain and fever.
These effects usually disappear after 24 to 48 hours. Although fever is not uncommon for 2-3 days, a high temperature is rare and may indicate that you in fact are infected with COVID-19 or another infection. Symptoms after vaccination usually last less than a week.
Article submitted by the HPA Saúde Group