BRUSSELS — Belgium will use the 443,000 doses of AstraZeneca COVID-19 vaccine the country will receive over the course of February to vaccinate people under the age of 55.

Regulators in the country of 11.5 million inhabitants have advised against the use of the AstraZeneca vaccine for older people due a lack of data about its efficacy, so Belgium’s vaccination task force has reshaped its strategy.

It decided that the doses will go in priority to health care workers under 55 as well as residents and staff in collective care institutions in that age group. Sabine Stordeur, who co-chairs the task force, said on Tuesday that people from high-risk groups with underlying conditions and police officers working in the field will also be offered AstraZeneca injections.

People over 55 will continue to receive the two other vaccines approved in the EU, Pfizer/BioNtech and Moderna.

Infection numbers have reached a plateau in Belgium, with new daily cases between 2,000 and 2,500, while coronavirus-related deaths are decreasing. So far, some 336,300 Belgium’s residents have received a first vaccine dose.