I’M NOT A FAN: Why are there so many new tick-borne diseases? “Improvements in medical technology, mostly. The newly discovered tick-borne diseases have probably been infecting humans for years, but they’re not easy to spot. Many victims never realize a tick has bitten them, and the symptoms, such as fevers, aches, and fatigue, are not distinctive and mirror those of common summer viral infections. The patient’s immune system usually fights off the illness unassisted, so doctors don’t bother running the battery of tests required to identify a new pathogen. Only in the rare cases when a patient struggles with the infection are physicians likely to make a genuine discovery. (The disease identified this week, a member of the phlebovirus family, hospitalized two men in Missouri.) They order blood smears or antibody tests to identify the presence of a pathogen, and genetic analyses—which were either inefficient or completely unavailable to doctors just a few years ago—alert researchers to the presence of the previously unidentified bug. Researchers have also become more aggressive recently, with some searching within ticks themselves for evidence of new pathogens. Lyme disease is a classic example of how long a disease can exist in a population without being identified.”