Taking vitamin B1 does not prevent mosquito bites

By Chang Tsung-chiu and Sherry Hsiao  /  Staff reporter, with staff writer

Wed, Sep 12, 2018 - Page 4

As the number of dengue fever cases rises, doctors in Changhua County have rejected online claims that taking vitamin B1 prevents mosquito bites.

A rumor has been circulating online that taking one or two 100mg tablets of vitamin B1 will cause a person to develop a scent that repels mosquitoes.

Vitamin B1 tablets only affect the smell of urine, and usually only for the first time a person urinates after taking the tablets, said Chien Chien-wen (錢建文), director of pediatric nephrology at Changhua Christian Children’s Hospital.

It is impossible for the body to maintain a scent that repels mosquitoes just by taking vitamin B1, he said.

The rumor is not backed by clinical observations, Chien said, adding that the ability to repel mosquitoes has nothing to do with taking vitamin B1 tablets.

Whether a person will be bitten by a mosquito has to do with body temperature, odor, sweat or the use of perfume, Changhua Hospital Infectious Disease Department doctor Chuang Chia-hui (莊佳慧) said, adding that people who sweat easily are more likely to attract mosquitoes.

Asian tiger mosquitoes and Aedes aegypti, also known as the yellow fever mosquito, are primary vectors of dengue fever, she said.

These types of mosquitoes most frequently appear around 9am and 5pm, so people should avoid visiting places with lots of mosquitoes during these times, she added.

There is no scientific evidence supporting the rumor that taking vitamin B1 tablets can repel mosquitoes, Changhua County Public Health Bureau Director Yeh Po-yen (葉彥伯) said, adding that the most direct and effective way to avoid mosquitoes is to eliminate them.

People should keep containers clean and avoid leaving water in them to eliminate mosquito breeding grounds, he said.