Booster shots are not enough to end the pandemic, says WHO

Fighting the Covid-19 pandemic with booster doses of current vaccines is not a viable strategy, warned this Tuesday (11) experts from the WHO (World Health Organization), who called for vaccines that better prevent transmission.

“A vaccination strategy based on repeated boosters of the first vaccines is unlikely to be appropriate or feasible,” the expert group charged with overseeing coronavirus vaccines said in a statement.

In addition, these experts consider “that vaccines against Covid-19 of high impact in terms of transmission and prevention of infection, in addition to preventing serious forms of illness and death, are necessary and must be developed”.

This would limit the impact of Covid in terms of health, but also “the need for rigorous and large-scale sanitary and social measures”, they argue.

“While we await the availability of such vaccines, and as the Sars-CoV-2 virus evolves, it may be necessary to update the composition of current anti-Covid vaccines in order to ensure that [elas] continue to provide WHO-recommended levels of protection against infection and disease” caused by variants, including the micron.

Just over six weeks after its identification in South Africa, data from several countries converge on two points: the Ômicron – which falls into the WHO’s category of variants of concern – is transmitted much faster than the previously dominant variant, the delta, and appears to cause less severe forms of the disease.

“However, there is a need to obtain more data on the effectiveness of vaccines, in particular with regard to hospitalizations, severe forms of the disease and deaths”, note the WHO experts.

Important point: it is not known whether this apparently lower severity is due to the intrinsic characteristics of the variant, or whether it is related to the fact that it affects populations already partially immunized by the vaccine or by a previous infection.

Still, the onomicron is advancing rapidly in many countries and cases are doubling every two or three days, something unheard of in previous variants.

Mutations in the omicron appear to allow it to reduce antibody immunity to the virus. Consequence: it can probably contaminate a large number of vaccinees and reinfect people previously infected with the virus.

WHO experts are calling for changes to the composition of vaccines to ensure they protect more against disease and continue to meet criteria set by the organization, including protection against severe forms of Covid.

In particular, they call for vaccines “to be based on strains . . . close to circulating variants.”

Experts also consider it important that “vaccine manufacturers take short-term steps to develop and test immunizations against dominant variants and share this data” with the WHO.

The organization wants to end the pandemic this year. For this, all countries would need to vaccinate 70% of their population by mid-2022.

But this goal is still far from being achieved. Globally, more than 8 billion doses of anti-Covid vaccines have been administered in at least 219 countries or territories, according to a count made by AFP from official sources.