A GOP congressman spotted walking around Congress without a mask said "there's just no need" to wear one because of herd immunity

• Republican Congressman Ted Yoho was seen walking around Congress without a mask, CNN first reported.
• When questioned by a reporter about why he wasn't wearing a mask, Yoho cited herd immunity, responding, "There's just no need."
• However, early evidence shows that herd immunity may not apply to the coronavirus pandemic, and that no country has come close to testing for the antibody rates required for herd immunity.
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There's early evidence that relying on herd immunity won't work against the coronavirus. But that didn't stop one congressman from citing "herd immunity" as the reason he isn't wearing a mask in Congress.

Representative Ted Yoho, a Florida Republican, was seen walking around the House floor without a mask on Friday, CNN first reported. When asked why he wasn't wearing a mask despite CDC guidance to the contrary, he responded, "There's just no need."

Yoho, a former veterinarian, said that wearing a mask is not necessary because of "herd immunity." However, reports from Sweden, a country that used a herd-immunity approach to combat the virus, show that the strategy is less effective than many had hoped.

When the CNN reporter pointed out that there's no evidence that herd immunity applies in the case of coronavirus, Yoho responded, "Viruses do what viruses do."

The term "herd immunity" is from veterinary practice, originally used when dealing with animal illnesses in livestock herds. However, World Health Organization emergencies director Dr. Mike Ryan noted, "Humans are not herds." Ryan said that the economics of herd immunity rely on the belief that an individual animal doesn't matter when making the decision to allow a pathogen to spread throughout a herd.

Herd immunity is achieved when a large enough percentage of a population is immune to a pathogen so that it can't widely spread. For the coronavirus, that percentage is estimated to be between 50% and 70%. However, in New York City, one of the hardest-hit locales in America, only around 21% of people in a study tested positive for antibodies. Currently, no country is even close to reporting the antibody rate required for herd immunity.