Reinfection
Reinfection refers to the process by which a person becomes infected again by a bacterium, virus, or fungus after recovering from a previous infection. Certain individuals, particularly those with weakened immune systems or those on immunosuppressive medications, are more vulnerable to reinfections. Common examples include urinary tract infections (UTIs), which can recur in up to 50% of women, and reinfection with Helicobacter pylori, occurring at a rate of approximately 9% per year among those previously treated. Individuals with autoimmune diseases, such as rheumatoid arthritis, or those undergoing chemotherapy for cancer, face heightened risks due to medications that suppress their immune responses. Additionally, people with acquired immune deficiencies, like AIDS, or genetic immune disorders are similarly susceptible to reinfections. The consequences of reinfection can be serious, resulting in complications such as kidney infections or the potential development of peptic ulcers and stomach cancer from H. pylori. Reinfections also contribute to the challenge of antibiotic resistance when treatment regimens are not fully adhered to. Understanding reinfection is essential for effective management and prevention in vulnerable populations.
Reinfection
Definition
A reinfection occurs when a bacterium, virus, or fungus reemerges to infect a person after he or she has recovered from an initial infection. Some persons are more prone to reinfections than others, such as those with impaired immune systems or those who must take immunosuppressant medications. In addition, some types of infections are more likely to occur as reinfections. For example, simple urinary tract infection (UTI) in women will reoccur in up to 50 percent of cases within a few months; the rate can be higher in more complex cases. In another example, research indicates that those persons who are cured of an infection with Helicobacter pylori, bacteria that infect the stomach, are reinfected with H. pylori at a rate of about 9 percent per year.
Immunosuppressant Medications
People who must take immunosuppressive drugs, or immunosuppressants, for autoimmune diseases that attack the body are at risk for reinfection. For example, persons with rheumatoid arthritis are at increased risk for reinfection because they take immunosuppressive medications, such as methotrexate, to decrease pain and other symptoms. These drugs may need to be discontinued if the sick person is hospitalized for a serious infection, such as pneumonia. Others who must take immunosuppressants to treat disease symptoms include persons with inflammatory bowel disease or psoriasis and persons who have received a transplanted organ. Transplant recipients take immunosuppressant drugs so that their bodies will not reject the transplanted organ; these drugs must be taken for life.
Cancer
Cancer can cause an immune deficiency, particularly among those persons who must have chemotherapy treatment. This treatment can significantly reduce the number of white blood cells produced and can thus leave the person more prone to both infections and reinfections. Persons with cancer who are receiving chemotherapy should be sure to contact their physician or nurse if they have a fever of 100.5 degrees F or greater. An infection may be causing the fever, and it is necessary to determine if immediate treatment is needed.
Acquired Immune Disorders and Inherited Immune Deficiencies
People with the acquired immunodeficiency syndrome (AIDS) have an elevated risk for reinfection because their immune systems work poorly. AIDS is caused by infection with the human immunodeficiency virus, which is primarily contracted during unprotected sex with an infected person or when sharing needles in intravenous drug use.
Some people are born with an impaired immune system called common variable immune deficiency (CVID); others are born with related immune deficiency disorders. These disorders are genetic, thus they cannot be transmitted to others. Most people with CVID have pneumonia a minimum of one time in their lives, and many have repeated bouts. These disorders are generally more likely to be linked to males rather than females because many genetic disorders that impair the immune system are X-linked; that is, they are linked to the X chromosome. In many cases, the disorder is not diagnosed until adulthood. About 1 in 50,000 people in the United States has CVID.
Impact
Reinfection, which can cause serious pain and discomfort, can also lead to further complications. For example, reinfection of the urinary tract may lead to kidney infection if it is not treated, and reinfection with H. pylori bacteria can lead to the development of peptic ulcers and stomach cancer.
The use of antibiotics for infections can lead to antibiotic resistance if the person taking the medication does not follow through with the treatment plan. Also, reinfection exacerbates the problem of antibiotic resistance if that person has developed resistance to that particular antibiotic.
Bibliography
National Institutes of Health, Genetics Home Reference. “Common Variable Immune Deficiency.” ghr.nlm.nih.gov/condition/common-variable-immune-deficiency. Accessed 29 Dec. 2024.
Parker, James N., and Philip M. Parker, eds. The Official Patient’s Sourcebook on Urinary Tract Infection. San Diego, Calif.: Icon Health, 2002.
Ryu, Kum Hei, et al. “Reinfection Rate and Endoscopic Changes After Successful Eradication of Helicobacter pylori.” World Journal of Gastroenterology 16, no. 2 (2010): 251-255.
Weiner, I. David, and Christine Adamec. The Encyclopedia of Kidney Diseases and Disorders. New York: Facts On File, 2011.
“Why Do Urinary Tract Infections (UTI) Recur?” American Society for Microbiology, 3 May 2024, asm.org/articles/2024/may/why-urinary-tract-infections-uti-recur. Accessed 29 Dec. 2024.