Why do people get the flu vaccine even though it has a lot of mercury?

"The multi-dose flu shot does contain a preservative called thimerosal, which breaks down into 49% ethylmercury and used to prevent bacterial contamination of the vaccine container. Ethylmercury, is processed differently by the body than methylmercury, the neurotoxin that can build up in the body and is found in fish. (Keep in mind the difference a letter can make in chemistry: methanol is anti-freeze while ethanol is a Chardonnay.) Ethylmercury is made of larger molecules that cannot enter the brain and exits the body within a week."