HIV attacks the cells of your body's immune system. You need a strong immune system to fight off germs like bacteria and viruses, so having HIV may give those germs a better opportunity to make you sick. When germs take advantage of your weakened defense system, they are called opportunistic infections (OIs).
Opportunistic infections that other people might fight off easily could make you really sick if you have HIV. Getting one or more of these OIs could mean that your HIV has advanced to AIDS. In fact, opportunistic infections are the most common cause of death for people with HIV/AIDS. The good news is that you have plenty of ways to prevent them.
The CDC has made a list of more than 20 serious diseases that can become OIs if you have HIV/AIDS. You might have one of these diseases and be healthy enough to fight it off normally, but if it is hard to get rid of and lasts too long, it is considered an OI.
If you have one or more of the diseases on the CDC's list, you could be considered to have AIDS--that's why the CDC calls them AIDS-defining conditions. Here are the most common OIs:
Candidiasis. A fungal infection you can get in your mouth, throat, digestive system, or vagina.
Cytomegalovirus. A viral infection that can cause blindness.
Herpes simplex virus. This can cause a serious outbreak of cold sores.
Mycobacterium avium complex. A bacterium that causes fever, digestive problems, and weight loss.
Pneumocystis. A fungal infection that can cause a severe type of pneumonia.
Toxoplasmosis. A protozoal infection that can cause brain damage.
Tuberculosis. A bacterium that can infect both your lungs and your brain.
Kaposi's sarcoma. A cancer often marked by red, purple, brown, or black skin blotches or nodules.
Other OIs include lymphoma, encephalopathy (AIDS dementia), and wasting syndrome, often marked by weight loss, ongoing fever, diarrhea, and malnutrition.
HIV targets cells in your body called CD4 cells. Measuring your CD4 count is one of the best ways for your doctor to tell how well your immune system is working. One of the best ways to prevent an OI is to keep your CD4 count above 200. A CD4 count below 200 means you have AIDS and could be at risk for OIs. The CDC recommends that you and your doctor consider starting HIV treatment if your CD4 count falls below 500. Other organizations recommend starting HIV treatment as soon as the patient is willing to start therapy, no matter how high the CD4 count.
Some OIs can be prevented by avoiding them, and others can be staved off by getting vaccinated. Some are really common, so you need to take special precautions to prevent being exposed to them. If you do develop an OI, it's important to get diagnosed and treated right away. So, it's a good idea to see your doctor at least once every three months.
Here are other important tips:
Practice safe sex. Several OIs are transmitted sexually. You can help prevent them by always practicing safe sex.
Practice safe food preparation. Some OIs can get into your body through the food and water that you eat and drink. Always rinse meats, rinse and peel fruits and vegetables, and avoid eating any raw or undercooked foods. Avoid drinking water that may not be clean.
Take care around animals. Animals can transmit some OIs to people with HIV/AIDS. Make sure pets are vaccinated and your cat stays inside. Wash your hands after handling any animals, and wear gloves when changing cat litter. Avoid animal feces when working outside in the soil.
Take care around people. People-to-people spread of OIs is also common. Avoid people who are sick, especially with diseases like pneumonia or tuberculosis. Use your own towel to wipe off gym equipment. Never share needles.
Keep a health journal and write down any new symptoms. If you have a new symptom, don't wait three months to see your doctor. Make an appointment right away. If you get treated for an OI, make sure to take all prescribed medication and keep all your follow-up appointments.
If you are having trouble keeping your CD4 count above 200, your doctor may consider putting you on preventive or maintenance therapy. That means taking medications to prevent an infection or to prevent an infection from coming back. Working closely with your doctor and taking reasonable precautions will help you reduce your risk of getting an OI. And don't forget about healthy lifestyle choices like good nutrition, proper sleep, and regular exercise.