In India, Plasmodium vivax malaria is predominantly transmitted in which ecological zone and is associated with which vector?

Explanation

## Plasmodium vivax Transmission in India: Ecological Zones and Vectors **Key Point:** P. vivax is the predominant malaria parasite in India and is primarily transmitted in hilly and foothill regions by Anopheles fluviatilis. ### Distribution of Malaria Vectors in India by Ecological Zone | Ecological Zone | Primary Vector | Secondary Vector | Predominant Plasmodium Species | |---|---|---|---| | Hilly/Foothill | An. fluviatilis | An. culicifacies | P. vivax | | Coastal plains | An. stephensi | An. culicifacies | P. falciparum | | Forest/Tribal areas | An. culicifacies | An. fluviatilis | P. vivax, P. falciparum | | Desert regions | An. culicifacies | An. annularis | P. vivax (limited) | **High-Yield:** - **Anopheles fluviatilis** is a hill-stream breeder found in foothill and hilly regions; it is the primary vector for P. vivax in these areas. - **Anopheles stephensi** breeds in urban and periurban water bodies (cisterns, tanks, wells) and is the vector in coastal plains and urban areas. - **Anopheles culicifacies** is a generalist breeder found across multiple ecological zones. **Clinical Pearl:** P. vivax accounts for approximately 50–60% of malaria cases in India, with highest prevalence in the northeastern states and hilly regions of central India. The shift toward P. vivax in recent years is partly due to vector control measures reducing An. stephensi populations. **Mnemonic:** **F-V-H** = **Fluviatilis–Vivax–Hill regions** — remember that fluviatilis (stream-breeding) is the vector for vivax in hilly terrain.