Flu Medicine Helps Spread Virus
January 22, 2014

Flu Medicines May Actually Help Spread The Virus

[ Watch the Video: Can OTC Meds Contribute To The Spread Of Flu? ]

Brett Smith for redOrbit.com - Your Universe Online

If you’re one of the unlucky individuals to experience flu season first-hand, you may want to skip the flu medications altogether, as a new research review published in the Proceedings of the Royal Society B has found that these drugs can aid the spread of the influenza virus.

Over-the-counter flu medicines typically include ibuprofen, acetaminophen and acetylsalicylic acid. These active ingredients work to bring down fever and deliver some relief from the aches and pains that typically accompany the flu.

"When they have flu, people often take medication that reduces their fever. No-one likes to feel miserable, but it turns out that our comfort might be at the cost of infecting others," said study author David Earn, a researcher from the Michael G. DeGroote Institute for Infectious Disease Research (IIDR) at McMaster University in Canada.

"Because fever can actually help lower the amount of virus in a sick person's body and reduce the chance of transmitting disease to others, taking drugs that reduce fever can increase transmission. We've discovered that this increase has significant effects when we scale up to the level of the whole population."

"People often take - or give their kids - fever-reducing drugs so they can go to work or school," Earn added. "They may think the risk of infecting others is lower because the fever is lower. In fact, the opposite may be true: the ill people may give off more virus because fever has been reduced."

In the review, researchers cobbled together information from a range of sources, including data from human volunteers and experiments involving ferrets, considered the premier animal model for studying human influenza. Using mathematical modeling, the researchers determined how the spread of virus from a single person taking fever-reducing drugs might increase the total number of cases in an average year, and in a year when a new strain of the virus caused a flu pandemic.

The study team discovered that treating a fever increases the number of annual cases by about five percent, the equivalent of over 1,000 additional deaths from influenza in an average year across North America.

"This research is important because it will help us understand how better to curb the spread of influenza," said David Price, chair of family medicine for McMaster's Michael G. DeGroote School of Medicine, who was not involved in the research.

"As always, Mother Nature knows best,” Price added. “Fever is a defense mechanism to protect ourselves and others. Fever-reducing medication should only be taken to take the edge off the discomfort, not to allow people to go out into the community when they should still stay home."

"People are often advised to take fever-reducing drugs and medical texts state that doing so is harmless," added study author Paul Andrews of the university’s Department of Psychology, Neuroscience and Behaviour. "This view needs to change."

"Although we have put together the best available estimates for each parameter in our model, we have a long way to go before we can make concrete policy proposals,” said co-author Ben Bolker, a mathematician at McMaster.

"We need more experiments to determine precisely how much reducing fever increases viral shedding in humans, and to estimate how much more people spread disease because they are more active in the community when they alleviate their symptoms by taking medication."