With Brazil still registering thousands of new coronavirus infections daily, politicians are keen to strike deals with vaccine makers to try to protect Brazilians from Covid-19.

On Wednesday, the governor of Brazil's most populous state, São Paulo, said he expects to start immunising the population with a Chinese-made coronavirus vaccine in December.

Joao Doria said five million doses of the Sinovac vaccine would be delivered next month. He added that he hopes the entire state could be vaccinated by the end of February.

Doria said there were encouraging signs that the Sinovac vaccine was safe, after it reached the third stage of tests with 50,000 volunteers in China. If the vaccine is approved by the Brazilian authorities it will then be rolled out across the country.

Brazil has recorded more than 4.6 million infections since the pandemic began, while on Wednesday the official death toll rose to 138,977.

There are around 40 different vaccines around the world in clinical trials, with research happening at breakneck speed. Most experts think a vaccine is likely to become widely available by mid-2021.