New Delhi, Oct 15 (PTI) Healthy people might have to wait till 2022 to get COVID-19 vaccine as health workers and those with a higher risk of contracting the infection will be prioritised, the World Health Organization (WHO) said.

Addressing an online question and answer session, WHO's chief scientist Soumya Swaminathan said there would be at least one effective vaccine by 2021 but it would be available "only in limited quantities".

"Most people agree, it's starting with healthcare workers, and frontline workers, but even there, you need to define which of them are at highest risk, and then the elderly, and so on," Swaminathan said on prioritising who gets the vaccine first.

"There will be a lot of guidance coming out, but I think an average person, a healthy young person might have to wait until 2022 to get a vaccine," she said.

She said no one has produced these vaccines in the volumes that are going to be needed.

"So in 2021 we will have vaccines but they will be in limited quantities so we worked on a framework that how the countries will prioritise on whom to give those vaccines," she said.

"People tend to think that on the first of January or the first of April, I'm going to get the vaccine, and then things will be back to normal.It's not going to work like that," Swaminathan added.

Union Health Minister Harsh Vardhan said on Tuesday said that India is expected to have a COVID-19 vaccine from more than one source by early next year and the government is formulating distribution strategies for the immunisation of people across the country.

He had also said the Centre estimates to receive and utilise 40-50 crore doses of a COVID-19 vaccine, covering 20-25 crore people, by July next year.

On Sunday, the minister said considering the large population size of India, one vaccine or vaccine manufacturer will not be able to fulfil the requirements of vaccinating the entire country and added that the government is open to assessing the feasibility of introducing several COVID-19 vaccines in the country in accordance with their availability.