Covid: diarrhea, vomiting... The new symptoms of the BQ.1.1 variant

"We discover a little bit every day with this pandemic," says Antoine Flahault, director of the Institute of Global Health at the Faculty of Medicine in Geneva, Switzerland. For several days, the Covid virus has taken a new form among patients. In addition to the traditional cold, and the fever which causes fatigue, patients are now suffering from digestive disorders.

"In one afternoon, I had three patients in my office who complained of stomach aches before realizing that they were positive for Covid", says Jérôme Marty, president of the Union union. French for a free medicine (Ufml) general practitioner in Haute-Garonne.

Diarrhea, vomiting, stomach aches, these new symptoms are due to the new BQ.1.1 variant. This cousin of Omicron appeared a few weeks ago thanks to a sub-lineage of the variant, and now attacks the intestinal mucous membranes. “The virus is still mutating as much and this new variant could attack gastric tissue. This is due to the modification of the structure of the virus”, explains Yannick Simonin, virologist and lecturer at the University of Montpellier.

"It's not totally new, reassures Antoine Flahault, at the start of the epidemic in 2020, some patients had digestive disorders". But Omicron and the BA.4 and BA.5 variants, which had become the majority, had reinforced the symptoms of coughing, loss of smell and fatigue. “Today, some data suggest that with BQ1.1, stomach aches would become the main symptom,” says Yannick Simonin. “Some patients still have ENT disorders but it is marginal”, observes the general practitioner.

If these new symptoms do not worry the doctor, they could cause a major problem in monitoring the epidemic. As winter arrives, and the circulation of viruses will increase due to the drop in temperatures, doctors fear a confusion with gastroenteritis. With similar symptoms, patients will have less of a reflex to get tested for Covid, thinking they have simple gastro. "We must remain vigilant," says Jérôme Marty. "The perception of this disease will perhaps become problematic in the monitoring of the epidemic", indicates Yannick Simonin.

“Many people are already going under the radar without being tested, underlines Antoine Flahault. The risk is that people wait for the arrival of respiratory syndromes such as cough to be tested and therefore that they lower their vigilance in barrier gestures ". According to the researcher, this phenomenon of confusion could favor the multiplication of the virus.

Especially since the cases in Europe and especially in France are increasing. According to the Cov variant monitoring site Spectrum, BQ1.1 represented 6% of new Covid cases detected in France at the end of September. Ile-de-France is even at 11% of the cases detected.

An increase perceived by Jérôme Marty in his cabinet. “I see more and more patients with these symptoms,” he says. "It may become important in the coming weeks." For his part, Yannick Simonin assures "that the BQ1.1 tends to increase. This is the first time in several weeks that a sub-variant has increased to this point. It must be monitored".

On the other hand, no concern for the doctor as for the treatment of these new symptoms, "the patients must take the drugs which one usually takes in the event of digestive disorders", indicates Jérôme Marty.

For him, barrier gestures and wearing a mask remain the most effective weapon to avoid contamination, even with this new variant. “This variant is always transmitted by aerosol routes”, abounds Antoine Flahault, “and we know that ventilation and wearing a mask are very effective means of avoiding contamination”.

And the new "bivalent" vaccines aimed at protecting Omicron, BA.4 and BA.5 variants which are currently being administered in the new vaccination campaign started on October 1, may represent a hope for combating this variant. “Vaccines increase immunity. And all of them are effective against severe forms,” recalls the expert.

"Until now, vaccines inhibit variants, also recognizes Yannick Simonin. For this variant, we have no escape signals that would show that we can have serious forms despite vaccination, it's encouraging “, he rejoices.

On the hospitalization side, it is still the question mark, "finally, we have little perspective on this variant", indicates Yannick Simonin. "We do not yet know whether BQ.1. causes more hospitalizations or not", also concedes Jérôme Marty. Just like its transmission speed, "perhaps it is even more contagious than Omicron, we don't know," summarizes Antoine Flahault. The coming weeks should bring answers to researchers and doctors.