What types of invaders cause infection in humans Given an example each type?

Types of Invaders that Cause Infection in Humans

Bacteria: Bacteria are single-celled organisms that can cause a wide range of infections, such as pneumonia, tuberculosis, and food poisoning. One example of a bacterial infection is *Streptococcus pneumoniae*, which causes pneumonia.

Viruses: Viruses are even smaller than bacteria and can only reproduce inside the cells of living organisms. Viruses cause many common infections, such as the flu, measles, and AIDS. One example of a viral infection is the influenza virus, which causes the flu.

Fungi: Fungi are multicellular organisms that can cause infections such as athlete's foot, ringworm, and candidiasis. One example of a fungal infection is *Candida albicans*, which causes candidiasis.

Parasites: Parasites are organisms that live on or in another organism (the host) and get their food from or at the expense of their host. Parasites can cause infections such as malaria, schistosomiasis, and hookworm. One example of a parasitic infection is *Plasmodium falciparum*, which causes malaria.