Gloria Copeland, wife of televangelist Kenneth Copeland, said Jesus has already beaten the flu so Christians shouldn't be getting it anymore.
In the video she said: "Listen partner, we don't have a flu season... we've already had our shot, he bore our sicknesses and carried our diseases.
"By his stripes we were healed."
The Charity Commission told The Independent it will question Kenneth Copeland Ministries (KCM) as its Europe ministry is registered charity headquartered in Bath, Somerset. The ministry also published the video on its UK website.
A Charity Commission spokeswoman told The Independent: "Trustees must ensure that their charity only carries out activities within their charitable objectives and must ensure they protect the reputation of their charity.
"The commission will be contacting the Kenneth Copeland Ministries regarding material posted on the charity's website to determine whether there is a regulatory role for the commission."
The latest report by Public Health England showed seasonal flu levels remain high but are continuing to stabilise across the UK. So far 215 people have died in the UK this flu season.
Christian Medical Fellowship told Premier Copeland's advice against getting the flu vaccine is poor and has "no Biblical backing".
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