Roundworms are small parasites, about 6 inches long when full grown. They typically enter the human digestive tract after their eggs or larvae are ingested (unwashed vegetables are a common source of roundworm eggs). Roundworms cause several chronic diseases in infected humans and should be dealt with promptly to avoid prolonged discomfort.
There are several different types of tests used to determine the presence of roundworms in the human body. What type of test is administered relies somewhat on the type of roundworm or infection. Infections that result from roundworms include trichinosis, whipworm disease, ascariasis and strongyloidiasis. Tests used to determine the presence of these diseases include muscle biopsies, blood tests, stool analysis and sputum examination.
A muscle biopsy is sometimes used to test for roundworms, such as those that cause trichinosis. In a biopsy, a sample of muscle tissue is removed from the body and examined externally for roundworm larvae. Removal of the muscle tissue may be done through an endoscopy (surgical tube that can be inserted into bodily orifices). Muscle biopsies are generally performed alongside blood tests and after a patient’s medical history (such as foods recently ingested) is compiled.
A blood test is typically used when testing for roundworms. Specifically, a blood test known as an ELISA (enzyme linked immunosorbent assay) test is used. This blood test detects the presence of antigens produced by roundworms in the human body. Antigens are substances that promote the production of antibodies.
Some tests can be performed to check for the presence of roundworms in excretory products. Such products include stool and sputum. Sputum is mucus expelled through the mouth (typically through coughing) that often results from lung or bronchial infection. A stool test typically involves a doctor swabbing a piece of sticky cellophane tape across the anal area. The tape is then examined under a microscope to determine the presence of roundworm eggs or larvae. Excretion tests are accurate, but may take a few days to culture or fully examine.
Roundworms more often infect animals than humans. Because of this, roundworms do not typically stay in the digestive tract of humans for very long. Instead, they travel through the body and into other organs. This is known as visceral larvae movement or VLM. Symptoms associated with VLM include swelling of the organs, coughing, fever, asthma, pneumonia or, in severe cases, blindness. Seek medical attention and testing immediately if you notice any of these symptoms and have recently been exposed to a roundworm-infected area.