Each person is teeming with bacteria, and we have a lot of viruses, too. A lot of the bacteria that live on and in our bodies can cause disease even if they aren't causing problems at the moment (for instance, E coli in the gut). So, no way. If each person lived in isolation for a year they'd still come out teeming with germs. But maybe it would theoretically wipe out some certain pathogen – I can't think of any, though. We actually need our bacteria, a lot of what goes on is a symbiotic relationship.
Lisa Linnet, midwife
No. Not all diseases, though some of those diseases which are transmitted by direct person-to-person contact, but even most of them would become dormant and may not cause disease in the same person but might affect the other people at a later time via blood transfusion or other exchange of bodily fluids.
Many diseases are endemic in animals, and only occasionally jump species and infect humans, so NO.
Liang-Hai Sie, retired general internist, former intensive care physician
The answers that say 'No' are correct – lots of diseases would persist. Diseases with animal vectors (hantaviruses, plague, many others), or diseases that are environmental (cholera, listeria, salmonella) wouldn't be much affected. Chronic diseases would persist: hepatitis B and C, all eight of the human herpesviruses (such as chickenpox, genital herpes, Epstein-Barr virus), HIV, tuberculosis, leprosy, plenty of others.
But a fair number of quite nasty diseases might disappear. Measles would be gone after a couple of weeks of isolation. RSV and other respiratory viruses mostly would disappear. Even tough viruses like rotavirus, which can last weeks in the environment, would probably not make a year.
Influenza is an interesting case. Human flu would be gone, but there are closely-related influenza viruses in pigs (who got them from humans in the first place) that would almost certainly make the jump back into humans after some time – maybe after a few years, as human immunity waned.
Ian York, Virologist, immunologist, biologist, US Government
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