How to differentiate flu from Covid? How to protect yourself from BQ.1? Doubts about the rise in Covid cases

The growth of Covid cases in Brazil is already starting to be reflected in the increase in hospitalizations in ICU beds in the state of São Paulo and in the explosion of the positivity rate of tests in the private network, from 3% at the beginning of October to more from 23% by November 4th (an increase of 524%).

Allied to this, the arrival of a subvariant of the omicron, BQ.1, something that was expected by specialists, has caused concern, especially for its greater ability to escape antibodies.

Some measures, however, remain the same, such as the use of masks to prevent transmission, isolation for at least 5 to 7 days in case of a Covid diagnosis and updating with the most recent booster dose – at least for people. who took the last dose of the vaccine more than four months ago.

Here are some recommendations on how to prevent the transmission of the coronavirus and what to do to protect yourself from the new subvariants of the omicron.

How to differentiate flu and covid symptoms? According to experts, the differentiation of flu and Covid symptoms is not clear, especially in vaccinated people. In general, the most common symptoms of infection with the omicron variant of coronavirus (including subvariants) are sore throat, headache, runny nose, and fatigue (tiredness).

At a time of high cases, the chance of a flu infection being caused by an omicron is greater, but it is not possible to rule out other respiratory viruses, such as influenza. “In an ideal scenario, there would also be a test for influenza in the public network, but the offer is very scarce. Taking the test when you have flu symptoms to rule out whether or not it’s Covid is the first step”, says infectologist and professor at Unicamp, Raquel Stucchi.

I’m vaccinated with three or four doses for Covid. Can I get infected by the Omicron BQ.1 subvariant? Yup. Although they guarantee protection against severe and moderate cases, protection against infection is lower and people vaccinated with three or more doses can contract the coronavirus, says the clinical director of Fleury, Celso Granato.

“Some studies show that the added protection of a booster from the updated Omicron vaccines is slightly greater for mild infections. It will be important in the future that inhaled or nasal spray vaccines are given as they act to block the virus in your gateway, which are the airways”, he says.

Will getting a booster now protect me against the new strains of the virus? It depends. While Covid vaccines still in use offer good protection against severe cases and hospitalizations, even that protection tends to wane over time, around six to four months. Protection against infections, which is already naturally lower, is further reduced over time.

It is not yet possible to know, however, if a new vaccine against the micron in all people will offer lasting protection or if the ideal is to give annual boosters, as with the flu immunization.

The fall in the protection rate in vaccines against the coronavirus is relatively shorter than with other immunizers, recalls the infectious disease specialist and president of the immunization department of the Brazilian Society of Pediatrics, Marco Aurélio Sáfadi.

In this sense, older people with comorbidities who have not received a booster for a long time may benefit from a new dose, even if it is not yet updated to the new strains.

Should I wear a mask to avoid infection? Risk assessment today, with the withdrawal of public health protection measures, becomes individual, experts say. Despite this, the state government of São Paulo issued an alert this Thursday (10) about the high number of ICU admissions due to Covid in the state and highlighted the recommendation for the use of masks in places of high risk of transmission of the virus, such as hospitals, pharmacies, public transport, among others.

Faced with the much more transmissible omicron variant, it is important to consider reinforcing the masks to prevent infection — studies show that masks of the PFF2 or N95 type are more recommended to block their entry.

Considering hospital environments with a high incidence of sick people, doctors and specialists recommend using them if it is necessary to seek medical attention.

In general, Covid vaccines were developed to protect especially against hospitalization and death, but they do not have the power to fully contain the contagion itself. Thus, even vaccinated people can contract the virus and become sick, so it is important to continue wearing masks if you have contact with infected people or in situations of high risk of transmission.

In the collective sense, if all people in a closed environment are wearing masks, the chance of transmitting the virus is reduced by up to 70%, according to an article published in the journal Aerosol Science and Technology.

Does the effectiveness of vaccines decrease over time? What changes with the omicron variant? The studies carried out so far show that two doses of vaccines, against the omicron, have reduced efficacy.

According to a survey by the CDC (Centers for Disease Control and Prevention of the United States), the effectiveness of the booster dose drops after four months. Even with the drop, protection remains high, around 78%, says the agency.

A survey carried out in the United Kingdom pointed out that, in the context of the omicron, the booster dose provides 20 times greater protection for hospitalization and death compared to individuals with only two doses. The age cut was above 50 years.

When will the fifth dose be available? So far, the Ministry of Health, under Jair Bolsonaro (PL), says that the vaccination strategy for next year, as well as the number of doses used, is undefined.

The government plan of President-elect Luiz Inácio Lula da Silva (PT) also does not mention a vaccination strategy with a fifth booster dose for 2023.