One is declining immunity, because “the protection conferred by an infection or a vaccine dose decreases in time,” he told AFP.
The other came down to the new subvariants BA.4 and particularly BA.5, which are spreading more quickly because they appear to be both more contagious and better able to escape immunity.
Olivier Schwartz, head of the virus and immunity unit at the Pasteur Institute in Paris, said BA.5 was “taking over” because it is 10 percent more contagious than BA.2.
“We are faced with a continuous evolution of the virus, which encounters people who already have antibodies — because they have been previously infected or vaccinated — and then must find a selective advantage to be able to sneak in,” he said.
“Based on limited data, there is no evidence of BA.4 and BA.5 being associated with increased infection severity compared to the circulating variants BA.1 and BA.2,” the European Centre for Disease Prevention and Control (ECDC) said last week.
But rising cases can result in increasing hospitalisations and deaths, the ECDC warned.
Could masks be making a comeback over summer? (Photo by OSCAR DEL POZO / AFP)
Alain Fischer, who coordinates France’s pandemic vaccine strategy, warned that the country’s hospitalisations had begun to rise, which would likely lead to more intensive care admissions and eventually more deaths.
However, in Germany, virologist Klaus Stohr told the ZDF channel that “nothing dramatic will happen in the intensive care units in hospitals”.
Return of the mask?
The ECDC called on European countries to “remain vigilant” by maintaining testing and surveillance systems.
“It is expected that additional booster doses will be needed for those groups most at risk of severe disease, in anticipation of future waves,” it added.
Faced with rising cases, last week Italy’s government chose to extend a requirement to wear medical grade FFP2 masks on public transport until September 30.
“I want to continue to recommend protecting yourself by getting a second booster shot,” said Italy’s Health Minister Roberto Speranza, who recently tested positive for Covid.
Fischer said France had “clearly insufficient vaccination rates” and that a second booster shot was needed.
Germany’s government is waiting on expert advice on June 30 to decide whether to reimpose mandatory mask-wearing rules indoors.
The chairman of the World Medical Association, German doctor Frank Ulrich Montgomery, has recommended a “toolbox” against the Covid wave that includes mask-wearing, vaccination and limiting the number of contacts.