The director of the US National Institute of Allergy and Infectious Diseases and chief medical adviser to US President Joe Biden, Dr Anthony Fauci, has said that the optimistic turn in COVID-19 cases, hospitalisations and deaths could end in another spike in infections, but the US could still prevent that spike with higher vaccination rates, CNN reported on Monday.

Dr Fauci was quoted as telling Fox News: "If we don't do very well in that regard, there's always the danger that there will be enough circulating virus that you can have a stalling of the diminishing of the number of cases, and when that happens, as we've seen in the past with other waves that we've been through, there's the danger of resurgence."

"COVID-19 numbers are getting better. But where they go from here will depend on vaccinations," Fauci said.

According to data from Johns Hopkins University, although cases still remain high in the US, with an average of about 85,000 new infections a day as of 17 October 2021, they are down by more than 8,000 from the prior week.

Also, COVID-19 deaths are down an average of more than 200 a day from the start of the month.

However, progress in the numbers is still threatened, by the low rates of vaccination.

As of 17 October 2021, 57% of the total population was fully vaccinated against the virus, according to the US Centres for Disease Control and Prevention.

Dr Fauci has said a vast majority will need to be vaccinated, although health experts do not know exactly what proportion of the population needs to be protected to control the spread of the virus.