I learned in virology that the flu viruses people are concerned with containes 8 chromosomes and if a person is infected with more than one kind that they can recombine to make a new bug, which can be bad. What can be really bad is if there is a nasty new flu strain, such as the current avian flu bug they are talking about, right now it does not spread from person to person but if a person with a flu strain that does is infected with it they could recombine to make a superbug. Also common is for a middle host to get two strains, very commonly pigs, they'll get a human and avian virus and create hybrids that can infect and spread person to person. Now no one tell my professor that I learned anything in his class, would ruin my reputation as a microbe biggot, I'm officially only interested in bacteria not viruses
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