evidence: The insects deliver live malaria-causing Plasmodium parasites that have been genetically modified to not get people sick. The body still makes antibodies against the weakened parasite so it's prepared to fight the real thing. [...] Mosquitoes and malaria – a toxic relationship [...] Countries try to curb malaria with mosquito netting, insecticidal sprays, anti-malarial drugs and even by releasing genetically modified mosquitoes that can't bite or lay eggs.