
Most of the microorganisms that cause opportunistic infections (OIs) are extremely widespread, and a person may already be infected with many of them.
- Keep clean and avoid recognized sources of the bacteria that cause OIs to lower the risk of new infections.
- Even if a person has some OIs, they can take drugs to avoid the development of active illness. This is called prophylaxis.
- The most effective strategy to avoid OIs is to maintain personal hygiene and practice safe sex.
- Patients who are old and susceptible to OIs should be up to date on their immunizations and vaccinations.
6 most common opportunistic infections in the United States
- Herpes simplex virus 1
- Herpes simplex virus type 1 (HSV-1) infection is characterized by vesicular sores on the lips, mouth, and face, which crust in a few weeks. It can occasionally cause genital lesions.
- HSV-1 is highly infectious and spreads by direct touch, including sexual contact, with someone infected with the virus (even if lesions are not visible).
- Although no treatment will eliminate HSV-1 from the body, antiviral medication can limit and prevent outbreaks and lower the risk of transmission.
- People who have both human immunodeficiency virus (HIV) and HSV-1 are more likely to transfer HIV to a non-HIV partner during sexual contact.
- Kaposi’s sarcoma
- The most prevalent malignancy observed in patients with HIV is Kaposi’s sarcoma (KS). This malignancy is caused by the human herpesvirus 8 (HHV-8), commonly called the Kaposi sarcoma-associated herpesvirus.
- Deep kissing, unprotected intercourse, and needle sharing can spread the infection. It can pass from the mother to the child.
- HIV-related KS generally occurs exclusively in persons with severe HIV illness.
- Brown, purple, or pink lesions (or blotches) on the skin, typically on the arms and legs, neck, or head, and even in the mouth are common symptoms.
- KS can cause edema in the legs and damage the lungs and intestines.
- Tooth discomfort or tooth loss, weight loss, night sweats, or fever lasting more than two weeks are all possible.
- Antiviral drugs can decrease the progression of lesions and possibly cure the disease.
- Other KS therapies, such as laser therapy, aim to alleviate symptoms and enhance the look of lesions. Chemotherapy is another treatment option for KS.
- Lymphomas
- Lymphomas associated with HIV include a large group of cancers that begin in the cells of the immune system.
- The cancers can spread to different parts of the body, such as the central nervous system, liver, bone marrow, and gastrointestinal tract. Symptoms depend on where cancer resides.
- Treatment varies depending on specific cancer but can include radiation and chemotherapy.
- HIV medications help boost the immune system and the body fight cancer. The development of effective combination HIV therapy has greatly improved the outlook for persons with HIV-associated lymphoma.
- Tuberculosis
- Mycobacterium tuberculosis is caused by bacteria that spread via the air when a person with tuberculosis (TB) coughs, sneezes, or speaks. It spreads quickly in enclosed areas, such as low ventilated homes, shelters, and prisons.
- Fever, night sweats, weight loss, exhaustion, loss of appetite, and coughing are some of the symptoms.
- It is critical to take TB medicine exactly as directed (missed doses can result in the TB germ developing resistance to the drug).
- Some TB drugs can cause transient liver dysfunction, but after the treatments are discontinued, the liver normally recovers.
- Many people who are exposed to tuberculosis do not acquire active tuberculosis but do have a low level of TB in their bodies. If the doctor identifies a TB exposure but not active TB, they will suggest therapy to lower the chances of getting an active illness.
- Pneumocystis pneumonia
- Pneumocystis pneumonia (PCP) is a deadly fungal illness caused by Pneumocystis jirovecii.
- PCP is more common in those who have a CD4 count of fewer than 200 cells/mm3 of blood.
- Starting a combination of antiretroviral medication before the CD4 count falls below 200 or taking daily doses of preventive antibiotics if the CD4 count is already below 200, dramatically decreases the chance of getting PCP.
- The fungus can damage a variety of organs, and the most frequent is the lungs. Symptoms can include fever, shortness of breath, dry cough, night sweats, and fatigue.
- Salmonella septicemia, recurrent
- Salmonella is a bacterium that is commonly found in foods, such as raw chicken, eggs, and unpasteurized milk.
- It is found in water, soil, kitchen surfaces, animal excrement, raw meat, and on some animals, including reptiles.
- Reptiles are not suggested as pets for patients with HIV due to the danger of salmonella, especially if their immunity is compromised.
- Symptoms can include diarrhea and fever.
- Antibiotics are typically used to treat Salmonella septicemia. To avoid relapses, drug therapy could be necessary for the rest of one’s life.

QUESTION
Bowel regularity means a bowel movement every day. See AnswerHealth Solutions From Our Sponsors
Spach DH. Opportunistic Infections: Prevention. National HIV Curriculum. https://www.hiv.uw.edu/go/co-occurring-conditions/opportunistic-infections-prevention/core-concept/all
Thewellproject. What Are Opportunistic Infections? https://www.thewellproject.org/hiv-information/what-are-opportunistic-infections
Sepkowitz KA. Opportunistic infections in patients with and patients without Acquired Immunodeficiency Syndrome. Clin Infect Dis. 2002 Apr 15;34(8):1098-107. https://academic.oup.com/cid/article/34/8/1098/283412
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