Once upon a time in Moscow in the 30s of the 20th century there were two provinces endemic for tick-borne typhus - Ivanovo and Kostroma. By the beginning of the 50s, both endemic foci were eliminated. However, the Moscow region, where Moscow is located, turned out to be unfavorable for this disease. Often in a village near Moscow, throughout the winter, residents complained that their heads and hands were shaking violently at night, headaches and weakness. In the morning, patients forgot their symptoms and continued to do their daily activities, some of them even went to work. On