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Nausea, vomiting, diarrhea

Anywhere from 30% to 60% of people have short-term nausea, vomiting, or diarrhea in the early stages of HIV, Dr. Malvestutto says.

These symptoms can also appear as a result of antiretroviral therapy and later in the infection, usually as the result of an opportunistic infection.

"Diarrhea that is unremitting and not responding at all to usual therapy might be an indication," Dr. Horberg says. Or symptoms may be caused by an organism not usually seen in people with healthy immune systems, he adds.

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