What are Opportunistic Infections?

Opportunistic infections are illnesses caused by pathogens such as viruses, bacteria, protozoa and fungi that take advantage of a person’s weakened immune system. The inability to fight off invaders gives these infections an opportunity to enter the body, an opening rarely possible if only the person has a healthy body.

Causes of Weak Immune System
A weak immune system is caused by several factors and conditions such as pregnancy, ageing, ongoing medical procedures, and ongoing antibiotic treatment. Normally, opportunistic infections will not affect a healthy person, but if you have any of the following illnesses, you are at risk: recurring infections, HIV/AIDS, skin damage, leukopenia, and malnutrition. For people with HIV/AIDS, the most common opportunistic infections are the following: candidiasis, cervical cancer, herpes simplex virus, lymphoma, tuberculosis, pneumonia, Salmonella septicemia, wasting syndrome, and many more.

Testing for Opportunistic Infections
There are ways to be tested if you think you are infected with opportunistic infections or OI through blood tests. Patients with HIV/AIDS, for example, are at risk of getting infected and must be tested regularly. One type of blood test is to look for the antigens and/or antibodies. The antigens are traces of the germs that caused the opportunistic infection, while the antibodies are the proteins produced by the human body to fight off the infection. For people with HIV/AIDS, the CD4 cell count should be monitored, because it will determine how weak the immune system has become. The CD4 cells or T-cells are white blood cells that are responsible for suppressing and killing the cells infected by the virus.

HIV/AIDS and CD4 Cells
If the person has a very low CD4 cell count, it means that he/she is more likely to get sick or infected and will have a difficult time recovering. The human immunodeficiency virus often infects the CD4 cells and become part of the normal cells. As they destroy the person’s healthy cells, the HIV also multiplies, making it harder for the remaining white blood cells to fight off the infection. A CD4 test is taken by using a blood sample from the patient and then determining the count of several types of cells still present. Although the CD4 count is not exact, the laboratory technician can give a good proportion of CD4 cells by calculating the total white blood cells in the sample. A normal CD4 count should be between 500 and 1,600. A CD4 cell count below 200 will indicate that the person’s immune system has been severely damaged and is diagnosed with autoimmune deficiency syndrome or AIDS, the final stage of HIV.

Prevention of Opportunistic Infections
If you have HIV/AIDS, you should avoid getting infections through treatments such as antiretroviral therapy, taking prescribed medication (prophylaxis), getting vaccinations, practicing healthy eating habits, limiting your exposure to germs, drinking clean water only, and monitoring your CD4 cell count every 6 to 12 months.