Photo: PHILIPPE LOPEZ / AFP / Getty Images
The World Health Organization (WHO) said that the review of the information and scientific data related to the duration of immunity offered by vaccines against covid-19 indicates that it lasts up to six months after receiving the second vaccination (or the single dose in the case of the Jenssen vaccine).
“We have reviewed the data out there and most show that immunity lasts for up to six months,” said the Director of the WHO Immunization Department, Kate O’Brien, at a press conference.
The group that advises WHO on immunization issues issued the conclusions of the data analysis it has carried out in the last two days, but noted that it is too early to comment on the new omicron variant and how it responds to vaccines.
The advisory group formally recommended countries to act flexibly when planning the next phases of their vaccination programs to contain the pandemic, which last week alone caused 4.1 million new confirmed infections and 52,000 deaths worldwide.
Combination of brands
That flexibility consists of be able to immunize people with the first dose of one vaccine and the second dose of another, which will allow countries that do not have vaccine stocks to face the problem of an unpredictable supply.
On the other hand, many countries have up to four vaccines in their immunization plans against covid and being able to combine them will prevent some of those stocks from expiring and being lostO’Brien commented.
Nevertheless, the experts consider that whenever possible the doses of the same product are given.
Vaccines that have been authorized by the WHO and most regulators that are considered an international reference they offer “robust protection for at least six months against severe forms of the disease, although a certain decrease (in efficacy) has been observed in severe cases, especially in older adults and people with underlying diseases ”, explained the president of the group, Alejandro Cravioto.
Over booster dose
For this reason, the instance of scientists indicated that it maintains its recommendation that booster doses are only offered to those vulnerable groups, as well as to healthcare workers, particularly if they received inactivated virus vaccines, which corresponds to the technology used in the vaccines of the Chinese pharmaceutical companies Sinovac and Sinopharm.
These vaccines, which are on the WHO emergency use list, have been widely administered in many developing countries, including Latin America.
Then, health personnel “must receive the reinforcement as soon as possible”Cravioto noted. Reserving the third doses to the highest risk groups would allow poor countries, where vaccination rates are very low, to receive the vaccines they need, the organization defends.
– FDA authorized boosters from Pfizer and BioNTech for 16 and 17 year olds
– The data indicates that Ómicron is mild, according to the director of the CDC
– Sinovac: PAHO requires a third dose of Chinese vaccine to consider fully vaccinated people over 60