LONDON: A coronavirus vaccine is 鈥渦nlikely鈥� to ever completely eradicate the virus, and the disease may never disappear, the British government鈥檚 chief scientific adviser has warned.

鈥淚 think it鈥檚 unlikely that we鈥檒l end up with a truly sterilizing vaccine that completely stops infection. It鈥檚 likely that this disease will circulate and be endemic,鈥� Sir Patrick Vallance told a UK government committee.

The medical definition of endemic describes a disease that is constantly present in the population, much like seasonal flu.

鈥淢y assessment 鈥� and I think that鈥檚 the view of many people 鈥� is that鈥檚 the likely outcome,鈥� Vallance said.

鈥淐learly as management becomes better, as you get vaccination that will decrease the chance of infection and the severity of the disease 鈥� or whatever the profile of the vaccines are 鈥� this then starts to look more like annual flu than anything else, and that may be the direction we end up going in.鈥�

He said the only disease to have ever been completely eradicated is smallpox. Vallance also warned that a working vaccine is unlikely to be ready until next spring at least 鈥� still far faster than the approximate five-year development time of previous vaccines.

There are now a number of vaccines undergoing late-stage human trials in the US, the UK, China and elsewhere.

But a growing body of research suggests that a COVID-19 vaccine is unlikely to provide long-term protection against the virus, and may require annual inoculations.