What type of parasite is Strongyloides stercoralis?

Strongyloides stercoralis is classified as a nematode, which is commonly known as a roundworm. This classification is based on its morphological characteristics and life cycle. Nematodes are unsegmented, cylindrical worms that have a complete digestive system and exhibit bilaterally symmetrical bodies.

Strongyloides stercoralis specifically belongs to the family Strongyloididae, and it is known for causing strongyloidiasis in humans. This parasitic infection can lead to various gastrointestinal symptoms and may also result in serious complications, particularly in immunocompromised individuals. Understanding its classification as a nematode helps in identifying its biological behavior, pathogenicity, and appropriate treatment options.

In contrast, other options such as protozoa, cestodes, and trematodes represent different types of parasites. Protozoa are unicellular organisms, cestodes are segmented flatworms (like tapeworms), and trematodes are also flatworms but are commonly referred to as flukes. Each of these groups has distinct characteristics and mechanisms of infection that differentiate them from nematodes like Strongyloides stercoralis.