Up to 20,000 viruses per cough, researchers say

May 12, 2009 That's because as many as 20,000 viruses may be expelled in an average cough. What's more, researchers at Singapore's National University Hospital say as many as 3,000 droplets are produced in a standard cough.

Just one cough or sneeze is considered sufficient enough to infect many people, particularly those who are not vaccinated.

With the H1N1 virus spreading around the world, governments are running public health advertisements using people to observe good personal hygiene.