Study indicates that 8% of athletes have persistent symptoms after contracting Covid-19

After analyzing 43 scientific articles that describe the impacts of Covid-19 on athletes, researchers from the University of São Paulo (USP) concluded that, although the disease is asymptomatic or mild in the vast majority of cases (94%), somewhere around 8 % of this population develops persistent symptoms, which can affect performance and even delay the return to training and competitions.

In all, data from 11,500 athletes were analyzed, including high-performance amateurs and professionals. The work was funded by Fapesp (projects 17/13552-2, 19/05616-6, 19/14819-8 and 20/04877-8) and the results were published on Friday (27/05) in the British Journal of Sports Medicine.

“We studied both the acute condition of the disease, seeking to assess the manifestations and severity, as well as the persistent symptoms, recorded after the virus had already been eliminated from the body. It is something a little more comprehensive than what is conventionally called Covid long”, explains Bruno Gualano, professor at the Faculty of Medicine (FM-USP) and research coordinator. “It is a true compendium on the subject, which can guide health professionals who work with this population.”

According to the article, 74% of athletes had symptoms in the acute phase, the most common being anosmia/ageusia (46.8%), fever/chills (38.6%), headache (38.3%), fatigue (37.5%) and cough (28%). Only 1.3% progressed to the severe form of the disease.

Gualano points out that the rate of severe cases is similar to that observed in the average population. The percentage of asymptomatic cases is more difficult to compare. “Many infected with mild symptoms go unnoticed in the general population. Among athletes, who undergo frequent evaluations, these cases tend to be more diagnosed”, he says.

In the researcher’s assessment, the most innovative findings of the research refer to what happens after the acute phase. Between 3.8% and 17% of athletes (confidence interval with a mean value of 8%) develop persistent symptoms, including anosmia/ageusia (30%), cough (16%), fatigue (9%) and chest pain (8%).

“We observed that 3% develop exercise intolerance. It’s not something serious, life-threatening, but in the sporting context it can be a problem. In the case of elite athletes, any difference in preparation can determine who gets on the podium, so much competition “, says Gualan.

custom protocols

The protocols adopted by sports confederations in general authorize the return to practice five days after the onset of symptoms caused by SARS-CoV-2. In Gualano’s assessment, however, the study shows that not all athletes will be able to resume training during this period.

“The ideal is for the athlete to undergo a careful evaluation and, in case of persistent symptoms, it may be necessary to modulate the load or even postpone the return until the situation is resolved”, he says.

Although previous studies have suggested that Covid-19 would increase the risk of myocarditis in this population, the review conducted by the FM-USP group did not confirm the hypothesis.

“In studies in which there was some type of control group, it was not possible to observe a causal relationship between the infection and the heart problem. One possibility is that the athletes already had myocarditis, which was only discovered because of the imaging tests performed after to Covid-19. However, the absence of evidence does not mean that this relationship does not exist. More studies should be done on this”, he says.

Gualano points out other gaps in this field of knowledge that still need to be filled by future research. One of them is the impact of the omicron and its subvariants on athletes, since most of the articles predate the emergence of new strains of SARS-CoV-2.

“Apparently, a smaller number of athletes have come to us with persistent symptoms, but we don’t know if it’s because of the variant, vaccination or previous immunity. We also don’t know the vaccine response to the subvariants of the omicron. context of the pandemic”, he argues.