9. Pneumonia

The cough and the weight loss may also presage a serious infection caused by a germ that wouldn’t bother you if your immune system was working properly.

“There are many different opportunistic infections and each one can present differently,” Dr. Malvestutto says. In Ron’s case, it was Pneumocystis pneumonia (PCP), aka “AIDS pneumonia,” which eventually landed him in the hospital.

Other opportunistic infections include toxoplasmosis, a parasitic infection that affects the brain; a type of herpes virus called cytomegalovirus; and yeast infections such as thrush.

10. Night sweats

About half of people get night sweats during the early stages of HIV infection, Dr. Malvestutto says.

These can be even more common later in infection and aren’t related to exercise or the temperature of the room.

Similar to the hot flashes that menopausal women suffer, they’re also hard to dismiss, given that they soak your bedclothes and sheets.