When mosquitoes start buzzing each year, which virus should worry you most? According to 2018 surveillance data from health authorities, West Nile virus continues to be the leading mosquito-borne disease threat across the continental United States. This isn't about new treatments or vaccines—it's simply tracking what's happening in our communities.
The data shows a clear seasonal pattern: approximately 93% of all reported mosquito-borne disease cases that year occurred between April and September. That's the window when most people are exposed, though the report doesn't specify exact case numbers or compare severity between different viruses.
It's important to understand what this report is and isn't. This is surveillance—a snapshot of what was reported in 2018. It tells us West Nile was the most common threat that year and when cases peaked, but it doesn't explain why or predict future trends. The data helps public health officials monitor patterns, but it doesn't establish causes or evaluate prevention methods.