The malaria mosquito needs more than one family of odor sensors to sniff out its human prey, new research suggests. New research provides striking new evidence that Anopheles gambiae -- the species of mosquito that spreads malaria that infects some 250 million and kills 900,000 people annually -- has a second set of olfactory sensors that are fundamentally different from the set of sensors that scientists have known about and have been studying for the last 10 years.