The Average Human Body Harbors How Many Viruses?!

by Pamela J. Hobart

Do you feel sick right now? If you didn't, you might be about to: new research has found that even healthy human bodies harbor on average five viruses at any given time. Scientists at Washington University in St. Louis, Missouri collected more than 700 samples of bodily fluids from more than 100 healthy adults. The study's participants were screened beforehand to make sure they had no viral infections, and anyone who was recently diagnosed with human papilloma virus or experienced a genital herpes outbreak was excluded from the study.

Surprise! 92 percent of the pre-screened participants tested positive for at least one virus (despite lacking any symptoms), and some were harboring up to 10 or 15 viruses, bringing the average number to five. And, because researchers only tested select samples from each participant and not the entire body, it's possible that number might be even higher, scientists said.

As for the viruses themselves? Almost 40 percent of women tested were found to carry strains of HPV, and virtually all of the participants had adenoviruses (which cause the common cold, as well as pneumonia). While researchers noted that some viruses could be leftover from old infections, they also pointed out that dormant viruses tend to live inside cells, while the study's samples came from fluids. Translation? The viruses participants picked up were most likely fresh, and not lingering from previous infections. Gross!

If it's any consolation, your body is loaded with bacteria too — another number that had been significantly underestimated until relatively recently. The ratio of human cells to one-celled microbes in your body is a staggering 10 to one. Yes, you read that correctly — the average person hosts 10 germs for every one real human cell.

But don't freak out just yet. Bacteria microbes (which, unlike viruses, count scientifically as living organisms) mostly inhabit your digestive system, and if they're not healthy you may experience digestive problems. Scientists are only just beginning to understand how the thousands of strains of gut microflora work, but suffice it to say that our stomachs wouldn't be anywhere as efficient as they are without them. Probiotic supplements may help to restore balance to your gut ecosystem, in the case that antibiotics or poor diet have disrupted it.

But as for those mysterious viruses lurking in our systems? It's less clear whether they are also beneficial. Since we know that many of the viruses discovered by researchers at the Washington University in St. Louis do in fact cause disease, they're more dubious than ordinary gut microflora. Only more research can determine whether there's any benefit to humans in our apparent propensity to carry viruses around instead of killing them off once and for all after they enter our bodies.

Ugh, science.

Image: Kalim/Fotolia; Giphy