“The primary reason [for this increase] is that some individuals who were infected with Covid before have experienced a decline in their immunity against the virus over time,” Peng said, adding that the virus would continue to cause minor waves of infection.
The rise of new variant EG.5 is driving up infections and raising concerns. The WHO classified it as a “variant of interest” last week.
Disease control authorities in the city of Foshan in Guangdong said on Wednesday that the EG.5 variant was gaining dominance among the strains in the city.
The EG.5 variant was first detected in February. It is a descendant of the Omicron variant XBB.1.9.2 and has a mutation that helps it evade antibodies developed by the immune system in response to earlier variants and vaccines.
Globally, there has been a steady increase in the proportion of EG.5 infections. By mid-July, the global prevalence of EG.5 had reached 17.4 per cent. It was a notable rise from about a month earlier when the global prevalence of EG.5 was just 7.6 per cent. It became the dominant variant in the United States this week.
As of August 7, a total of 7,354 sequences of Omicron EG.5 from 51 countries had been submitted to GISAID, an international viral genome database. The largest portion, or 30.6 per cent, was submitted from China.