What is the common first-line therapy for most Schistosoma species infections?

• A. Praziquantel
• B. Albendazole
• C. Mebendazole
• D. Ivermectin

Answer: (A)

Praziquantel is the go-to therapy for most Schistosoma infections because it effectively targets the adult worms of all major human schistosome species and is well tolerated, making it suitable for widespread use. It works by disrupting the parasite’s tegument and increasing calcium influx, causing paralysis and death of the worms, and it also reduces egg production, which helps lower pathology and transmission. While other anthelmintics like albendazole or mebendazole are used for nematodes and tapeworms, they do not reliably kill schistosomes, and ivermectin is mainly for nematode infections and certain parasites, not schistosomes. For these reasons, praziquantel is the first-line option across Schistosoma species, with some programs sometimes organizing a second dose to catch any remaining juveniles.