US President-elect Joe Biden has set a goal of 100 million Covid vaccinations in his first 100 days in office.
Read MoreCovid-19 could be causing lung abnormalities still detectable more than three months after patients are infected, researchers suggest.
Millions of Indians have limited access to clean water, consume unhygienic food, breathe foul air and live in densely packed surroundings.
The analysis, which drew from hundreds of coronavirus cases in dozens of countries, found that some patients had symptoms for months after diagnosis.
Levels of protective antibodies in people wane "quite rapidly" after coronavirus infection, say researchers.
The UK is pushing ahead to be the first nation to carry out "human challenge" studies where up to 90 healthy people will be deliberately exposed to Covid.
The UK is pushing ahead to be the first nation to carry out "human challenge" studies where up to 90 healthy people will be deliberately exposed to Covid
Anti-viral drug remdesivir has little to no effect on Covid patients' chances of survival, a study from the World Health Organization (WHO) has found.
Johnson & Johnson has paused its Covid vaccine trial to investigate why one participant in the study fell ill.
Colds, flu and Covid-19 are caused by different viruses, but can have similar symptoms.