Few facilities in Africa have deep expertise in treating snakebites. Above, patients and their relatives wait to enter the one of them, the envenomation treatment center at the Institute for Applied Biological Research in Kindia, Guinea. Even in this specialized place, electricity is sporadic, and medical supplies are rudimentary.

Selling venom is profitable. On the outskirts of Paris, the manager of Venom World, Rémi Ksas (above), extracts venom from a West African Gaboon viper for a French lab that supplies ingredients to antivenom manufacturers worldwide. Venom can fetch thousands of dollars a gram.

On Friday, Whitney Johnson covers the latest in photography news. If you’re not a subscriber, sign up here to also get Debra Adams Simmons