Public healthGreater variety of U.S. flu strains alarming, but may not be new

New virus strains found throughout the central United States have alarmed health specialists, including officials at the Centers for Disease Control and Prevention (CDC), but other experts say that what appears to be an increase in the number of strains is merely the consequences of improved diagnosis technologies.

As theKansas City Star reports, new viruses discovered in that part of the country, including strains such as the Heartland and Bourbon viruses, are presenting doctors with a problem: there are no known vaccines or treatments.

The new cases, which have left vaccine manufacturers scrambling to respond, have health experts wonder whether these instances represent more of the same — or, rather, the appearance of deadly and unclassified diseases. The answer, according to some, is “yes — and yes.”

“In a lot of cases, they’re not new viruses. We just didn’t have the tools to identify them,” said Rafal Tokarz, a research scientist at Columbia University’s Center for Infection and Immunity. “In the past, it was probably something that would be missed or misdiagnosed.”

Dana Hawkinson, an infectious diseases specialist at the University of Kansas Hospital, has also considered the question. She was a member of the team which first diagnosed the Bourbon virus, one of the latest known to infect humans.

It is possible that countless other people have gotten ill from the Bourbon virus but typically recovered, he said. “They may have been misdiagnosed (with a different illness) or the doctor may have said, ‘I don’t know what you have, but you got better.’ That happens a lot.”

Additionally, those cases of Bourbon virus could have been occurring for “decades or centuries, for sure, maybe longer,” he added.

Advances in laboratory technology, however, are allowing researchers to discover new viruses which have yet to be seen infecting humans, though they very likely could.

In 2012 a group of British scientists counted 219 species of viruses which are known to be able to infect people. The team estimated that three to four new species were being found every year. Further, a team at Columbia University estimated that the world’s mammals, the most likely group to spread diseases to humans, carry at least 320,000 undiscovered viruses.

“That doesn’t necessarily mean they’re all pathogenic to us,” said Tokarz. “There is no way to know if they could infect people. It’s probably a very, very small percentage. The vast majority of viruses that scientists find don’t infect people.”

As an expanding human population moves closer to animal habitats, the number of viruses that people come into contact with may also increase.

“By extending our range, we encounter viruses we wouldn’t have otherwise,” he said. “It’s the nature of the world we live in now. It’s how it is, unfortunately.”

These revelations follow after reports traced major diseases such as the Ebola epidemic (fruit infected by bats), the hantavirus (deer, mice) and West Nile (mosquitoes and birds) to human contact with animals.

We are in a situation where there will be more bugs, said Nirav Patel, an infectious disease expert at St. Louis University, “There are going to be more outbreaks. It’s going to be something other than Ebola next time. We have to stay vigilant.”

Currently, the Kansas Department of Health and Environmentis in discussions with the CDC to study the basic questions surrounding the Bourbon virus.