Washington, Oct 29 (IANS): Only 27 per cent of parents in the US said they will vaccinate their kids between five to 11 years against Covid-19 "right away" once a jab is authorised for this age group, according to a new poll.

The survey of the Kaiser Family Foundation was conducted between October 14 to 24 among a nationally representative random digit dial telephone sample of 1,519 adults.

A third of parents said they will "wait and see" how the vaccine is working before having their 5-11 year olds vaccinated, while 30 per cent said they "definitely will not" get their younger kids inoculated, reports Xinhua news agency citing the poll released on Thursday as saying.

Parents' main concerns have to do with potential unknown long-term effects and serious side effects of the vaccine, including two-thirds who are concerned the vaccine may affect their kids' future fertility.

Advisors to the Food and Drug Administration (FDA) on Tuesday voted in favour of authorising the Pfizer-BioNTech vaccine for children aged five to 11.

The advisors said the benefits of the vaccine outweigh its risks for use in this age group.

Results from the Pfizer-BioNTech vaccine clinical trials show that it is safe and 90.7 per cent effective against symptomatic Covid-19 in children.

The FDA will consider formal authorisation of the vaccine based on its advisors' recommendation.

If authorised, it would be the first Covid-19 vaccine for younger children.