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Do viruses mutate at a predictable rate as they replicate?

Yes, and it is different for each type of virus; some have error-correction systems and some, like HIV, do not, which makes them extremely mutable.

What causes a mutation of a virus or bacteria?

Error-prone replication machinery always causes a few mutations. Then, chemical mutagens in the medium and ionizing radiation (UV, gamma rays) also contribute.

If the flu is found in any animal and can be 100% cured, can it still once again emerge later on in years?

Flu does not go latent in a cured animal or person the way herpes viruses do, so they do not re-emerge later. But a virus can disappear from the human population only to reappear years later; in that case it has probably been in an animal host.

I heard in the news about the H1N1 flu and it talked about how many women that are pregnant have died and lost their babies. Is that possible? How does that happen?

We do not yet know why this new flu seems to be particularly hard on pregnant women.

When you get the chicken pox vaccination, does it contain herpes 1 and herpes 2 virus?

No, only Varicella-zoster (chicken pox) virus, which is an distant member of the herpes family.

A classmate of my daughter's was diagnosed last week with seasonal flu, H1N1, and pneumonia. If she was exhibiting flu symptoms, would it be typical to test for all of these at the same time?

Pneumonia can be a consequence of flu, and can either be caused by the virus or by a secondary bacterial infection. No one has yet been reported to have pandemic H1N1 2009 and seasonal flu at the same time.

How can you attack or overcome viruses that get lodged into the DNA?

At this time we do not know how to get rid of latent viruses.

Measles Vaccine - As a youth the school system requires vaccine 3 times: kindergarten, jr high, and college entry. As an adult, do we need additional vaccines, and if so how often?

There are a series of vaccines recommended for adults; measles is not included. Read more:

How does the plague affect their animal carriers? Is there a difference between the effects on an insect like a flea and a mammal such as a rodent?

Fleas that acquire plague get “blocked” by the high numbers of bacteria, so when they bite a mammalian host the bacteria are regurgitated into the wound. The flea will die as it cannot absorb blood. Host animals (certain rodents) have lived so long with plague that they are not susceptible to it, but can pass it via flea bites to susceptible rodents and people.

Hasn't MRSA become endemic throughout the U.S. in the last few years?

Yes, there is community-acquired MRSA everywhere now.

How is the H1N1 that we face now, different from the H1N1 of 1918 and the H1N1 of 1977?

Very different. It just happens to have similar (but not identical) H and N genes.

How does the death rate with the current H1N1 compare to the common seasonal flu?

It is about the same or a bit higher. But it affects younger people more severely.