Which group feeds on blood and includes humans as disease vectors, with hosts on mammals and a head narrower than the prothorax?

Which group feeds on blood and includes humans as disease vectors, with hosts on mammals and a head narrower than the prothorax?

• A. Anoplura (Sucking Lice)
• B. Notonectidae (Backswimmers)
• C. Belostomatidae (Giant Water Bugs)
• D. Nepidae (Waterscorpions)

Answer: (A)

Blood-feeding ectoparasites of mammals rely on piercing-sucking mouthparts to obtain blood, and they can act as disease vectors. Among insects, the sucking lice fit this description: they feed on the blood of mammals, including humans, and their head is notably narrower than the prothorax, a shape that helps them remain anchored to hair and skin while they feed. The ability to transmit pathogens is a hallmark of these lice, which is why humans are considered disease vectors for certain conditions carried by them. The other options describe aquatic true bugs that are predators rather than blood feeders and do not typically parasitize mammals or transmit human diseases, and their body shapes and feeding habits don’t match the described features.

Blood-feeding ectoparasites of mammals rely on piercing-sucking mouthparts to obtain blood, and they can act as disease vectors. Among insects, the sucking lice fit this description: they feed on the blood of mammals, including humans, and their head is notably narrower than the prothorax, a shape that helps them remain anchored to hair and skin while they feed. The ability to transmit pathogens is a hallmark of these lice, which is why humans are considered disease vectors for certain conditions carried by them.

The other options describe aquatic true bugs that are predators rather than blood feeders and do not typically parasitize mammals or transmit human diseases, and their body shapes and feeding habits don’t match the described features.