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Fungal infections (mycosis) are diseases caused by fungi. Fungi are everywhere, but only some cause disease. Fungal infection occurs after spores are either breathed in, come into contact with skin or enter the body through the skin such as via a cut, wound or injection.
Different types are traditionally divided according to the part of the body affected:
Anyone can get a fungal infection, even people who are otherwise healthy. Fungi are common in the environment, and people breathe in or come in contact with fungal spores every day without getting sick. However, in people with weakened immune systems, these fungi are more likely to cause an infection.
Opportunistic infections are infections that happen because a person’s immune system is weakened. These illnesses can be caused by bacteria, viruses, or fungi. Many fungal infections are opportunistic infections.
Ringworm is a common skin infection that is caused by a fungus. It’s called “ringworm” because it can cause a circular rash (shaped like a ring) that is usually red and itchy. Anyone can get ringworm. The fungi that cause this infection can live on skin, surfaces, and on household items such as clothing, towels, and bedding.
Ringworm goes by many names. The medical terms are “tinea” or “dermatophytosis.” Other names for ringworm are based on its location on the body – for example, ringworm on the feet is also called “athlete’s foot.”
Fungal nail infections are very common. They may affect up to 14% of the general population. Fungal toenail infections are more common than fungal fingernail infections.
Most fungal nail infections are not serious. However, some people may experience pain or be bothered by the appearance of their nails.
Fungal nail infections may cause nails to become discolored, thick, fragile, or cracked. The nail may also become separated from the nail bed.
People who have fungal toenail infections often have a fungal skin infection on the foot, especially between the toes (commonly called athlete’s foot, ringworm on the foot, or tinea pedis).
More on fungal nail infections
Candidiasis is an infection caused by a yeast (a type of fungus) called Candida. Candida normally lives on skin and inside the body such as in the mouth, throat, gut, and vagina, without causing any problems. However, sometimes if the environment changes and allows for the Candida to multiply it can cause an infection.
Candida can cause an infection if conditions change inside the vagina to encourage its growth. Things like hormones, medicines, or changes in the immune system can make infection more likely. The common term for candidiasis in the vagina is a vaginal yeast infection. Other names for this infection are vaginal candidiasis, vulvovaginal candidiasis, or candidal vaginitis.
The symptoms of vaginal candidiasis include: vaginal itching or soreness, pain or discomfort during urination or sexual intercourse, and abnormal vaginal discharge. Vaginal candidiasis is often mild. However, some women can develop severe infections involving redness, swelling, and cracks in the wall of the vagina. Contact your healthcare provider if you have any of these symptoms.
Vaginal candidiasis is common. Women who are more likely to get vaginal candidiasis include those who:
Candidiasis in the mouth and throat is also called thrush or oropharyngeal candidiasis. Candidiasis in the esophagus (the tube that connects the throat to the stomach) is called esophageal candidiasis or Candida esophagitis. Esophageal candidiasis is one of the most common infections in people living with HIV/AIDS.
Candidiasis in the mouth, throat, or esophagus is uncommon in healthy adults. People who are at higher risk for getting candidiasis in the mouth and throat include babies, especially those younger than 1 month of age, and people with at least one of these factors:
Cancer Patients and Fungal Infections
As a cancer patient, you may have received a lot of information about your treatment and your journey to recovery. Chemotherapy and radiation cause many changes in the body as they destroy cancer cells. One major change is that these treatments weaken your immune system, which can increase your chances of getting an infection, including a fungal infection.
Stem cell transplant patients or those who have a blood (hematologic) cancer such as leukemia, lymphoma, or myeloma may have different risks for fungal infections.
Aspergillosis is a disease caused by Aspergillus, a common mold (a type of fungus) that lives indoors and outdoors. Most people breathe in Aspergillus spores every day without getting sick. However, people with weakened immune systems or lung diseases are at a higher risk of developing health problems due to Aspergillus. There are different types of aspergillosis. Some types are mild, but some of them are very serious.
Candida auris (C. auris) is a type of fungus that can cause serious illness in hospitalized patients. Infections with this fungus can be difficult to treat. C. auris only recently appeared in the United States, and public health officials are researching more about how it is spread.
Invasive candidiasis is an infection caused by a yeast (a type of fungus) called Candida. Unlike Candida infections in the mouth and throat (also called “thrush”) or vaginal “yeast infections,” which are localized to one part of the body, invasive candidiasis is a serious infection that can affect the blood, heart, brain, eyes, bones, or other parts of the body.
Candida can enter the bloodstream or internal organs and cause an infection. A Candida bloodstream infection, also called candidemia, is the most common form of invasive candidiasis. In the United States, candidemia is one of the most common causes of bloodstream infections in hospitalized patients, and it often results in long hospital stays and death. It is also responsible for high medical costs.
More about invasive candidiasis
Pneumocystis pneumonia (PCP) is a serious infection caused by the fungus Pneumocystis jirovecii.
PCP is extremely rare in healthy people, but the fungus that causes this disease can live in their lungs without causing symptoms. In fact, up to 20% of adults might carry this fungus at any given time, and the immune system removes the fungus after several months.
Most people who get PCP have weakened immune systems, meaning that their bodies don’t fight infections well. About 30-40% of people who get PCP have HIV/AIDS. The other people who get PCP are usually taking medicine (such as corticosteroids) that lowers the body’s ability to fight germs or sickness or have other medical conditions, such as: