Flu Is Transmitted Before Symptoms Appear, According to New Study
” …people [may possibly) pass on flu to others before they know they’re infected, making it very difficult to contain epidemics….”
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According to a study conducted in London, you may be contagious with the flu before you have flu symptoms. This might explain how quickly the flu can spread. The study was actually an animal study conducted with ferrets which mimic human biological responses in a number of ways. Since it was an animal study with a relatively small number of subjects and was also based on specific flu strains, we need not jump to the conclusion that this result necessarily applies to humans.