How a new Lyme vaccine for mice may protect people
A vaccine to fight Lyme disease, decades in the making, has received a temporary green light from the U.S. Department of Agriculture. But it’s not for people — it’s for mice. The vaccine isn’t a rodent-sized injection, which wouldn’t work for targeting large populations quickly. Instead, it’s coated onto edible, nutrition-free pellets that mice gobble up. The vaccine makes mice develop antibodies that neutralize Borrelia burgdorferi, the bacterium that causes most U.S. cases of Lyme disease. When ticks imbibe the blood of a vaccinated mouse, the idea goes, they won’t get an active infection and so can’t transmit the bacteria to people or other animals. “Mice are probably one of the most important reservoir hosts for Lyme disease,” especially in the Eastern United States where Lyme disease is rampant, says Jean Tsao, a disease ecologist at Michigan State University in East Lansing who was not involved in developing the new vaccine. Reservoir hosts...