Which of the following is categorized as a parasitic infection?

Malaria is categorized as a parasitic infection because it is caused by protozoan parasites of the genus Plasmodium, which are transmitted to humans through the bites of infected Anopheles mosquitoes. Once inside the human body, these parasites multiply in the liver and then infect red blood cells, leading to a range of symptoms including fever, chills, and flu-like illness. This makes malaria a classic example of a parasitic disease, as it relies on a host for survival and reproduction.

The other conditions mentioned are caused by different pathogenic organisms: Tuberculosis is caused by the bacterium Mycobacterium tuberculosis, cholera is an acute diarrheal illness caused by the bacterium Vibrio cholerae, and pneumonia can result from various pathogens including bacteria, viruses, or fungi but is typically not classified under parasitic infections. Understanding these distinctions is important for recognizing the nature of various infectious diseases and their prevention and treatment strategies.