The World Health Organization (WHO) considers the covid-19 pandemic to be moving at two very different speeds, with the disease impacting vaccinated and unvaccinated people.

On Thursday, the WHO said that in the case of vaccinated people, they may still be infected with the SARS-CoV-2 coronavirus but will have mostly more benign forms of the disease, while unvaccinated people are accounting for between 80% and 90% of serious infections, hospitalizations and deaths.

However, the director of the WHO's immunization department, Kate O'Brien, maintained in a press conference that "this should in no way be interpreted as a lack of effectiveness of the vaccines."

Thus, the WHO director revealed that "the greatest risk is for unvaccinated people, so there is a two-speed pandemic.

"As vaccination coverage increases, among the new cases there will be a higher proportion that correspond to vaccinated people. It's not surprising that as more people get vaccinated, we will see a higher number of infections," Kate O'Brien said during a presentation of the latest findings from the group advising WHO on immunization.

Meanwhile, as for the new covid-19 variant, Omicron, O'Brien said that this could create more pressure on vaccine stocks as well as change the plans of the richest countries, which have announced that they will donate their excess doses to the poorest countries and instead use them for booster vaccination of their populations.