Scientists create 'breathalyzer' for swine flu, halitosis

You may have read about breathalyzer-like devices that can sniff out halitosis, but did you know that a new technology can do the same for influenza?

A report published in the Journal of Breath Research (JBR) unveiled a technology that may be able to detect the presence of swine flu. A simple test similar to a breathalyzer, the device detects the presence of certain molecules on exhaled air.

The compounds, nitric oxide and isoprene, tend to appear in larger concentrations among people who have been infected with the H1N1 flu virus, also known as the swine flu, the team said. A simple, non-invasive breath test could allow physicians to determine which patients are uninfected, hence in need of a flu shot.

Isoprene and nitric oxide (NO) are organic molecules, constantly produced by your body as a part of its natural molecular functions. However, when you get the flu, you may produce more of them than usual.

The team reported that volunteers given an H1N1 flu shot displayed spikes in their exhaled isoprene and NO levels three days after the injection. Researchers explained that NO may play a part in the body's neutralization of viruses, while isoprene appears to indicate oxidative stress in the respiratory tract.

What does all this have to do with halitosis? More than you might think.

First of all, isoprene has a resinous, hops-like scent. That alone is enough to give your breath an unpleasant reek, as several studies can attest. Another report published in the JBR found that between birth and age 18, children's breath levels of isoprene double every five or six years.

A third study in the same journal noted that adults expel much more isoprene during exercise than at times of rest. The authors estimated that isoprene production quadruples in as little as one minute. This means that your breath can quickly go from fresh to foul, especially in adulthood.

Of course, there's another connection between influenza and halitosis that is much more basic. Regardless of which molecules carry what smell, people with the flu just get bad breath. If you've ever cared for someone who's stayed home with chills, a fever and a runny nose, you know that they tend to need a specialty breath freshener.

This kind of oral odor comes mainly from post-nasal drip. The flu causes your nasal passages to emit much more mucus than usual. As it slides down your throat, this phlegm feeds oral bacteria, which in turn give off the smelly compounds associated with bad breath.