Like a bad action movie sequel, West Nile virus is back, with a vengeance. Incidents of the mosquito-born illness have been reported in 32 states, including hard-hit Texas. Nationwide, it has caused 28 deaths so far this year.
The return of the virus can largely be blamed on this year's weather patterns. Warm, dry winters followed by rainy springs allowed mosquitos to start breeding early, and this summer's intense heat sped up the insect's lifecycle, so the virus has replicated faster.
There's no vaccine or proven therapy for the virus, which causes headaches, joint pain, vomiting or diarrhea, and rash.