The Brazilian city of Manaus has halted its vaccination drive against the novel coronavirus for at least 24 hours, CNN Brasil reported late Thursday, citing the city administration.

"Due to the small number of vaccine doses that the government of Amazonas state has passed on - 40,072 of 282,000 - the administration has had to revise the vaccination plan," the Manaus municipal administration was quoted as saying.

In addition Manaus, vaccinations were also suspended in Tupa in Sao Paulo state.

Meanwhile, a case of two sisters who were accused of having been vaccinated solely on the basis of family connections caused a stir in Manaus. They are the daughters of a well-known university director.

Politicians, entrepreneurs and civil servants were vaccinated in at least 11 Brazilian states and the capital district of Brasilia despite not belonging to the designated priority groups, the news site G1 reported.

Brazil is among the countries hit hardest by the coronavirus pandemic. Vaccinations only started there on Monday.

Manaus, the capital of Amazonas, recently registered the highest number of hospital stays in connection with Covid-19 since April 2020.

Supplies of oxygen are running out in clinics because they are treating so many Covid-19 patients.