A tick’s mouth parts under 40x magnification.
In the summer of 2009, two men from northwest Missouri showed up at Heartland Regional Medical Center in St. Joseph, tucked up against the Kansas border 50 miles north of Kansas City. The men were seriously sick. They had high fevers, fatigue, aches, diarrhea and disordered blood counts: lower than normal amounts of white blood cells, which fight infection, and also lower than normal platelets, cells that control bleeding by helping blood to clot. But they had none of the diseases that were high on the differential diagnosis, the list of possible causes that doctors work their way down as they try to figure out what has gone wrong: no flu, no typhus, no Clostridium difficile, and none of the serious foodborne illnesses — no Salmonella, no Shigella, and no Campylobacter.
The two men had one thing in common, though: About a week before being hospitalized, each remembered, he had been bitten by a tick.
