"A Potential Protective Measure for Humans: New Lyme Vaccine for Mice"

A vaccine for Lyme disease, which has been in development for decades, has been given a temporary green light by the US Department of Agriculture. However, it is not for human use, but for mice.

The vaccine has been coated onto edible pellets that are fed to the mice. It makes the mice develop antibodies that counteract Borrelia burgdorferi, the bacterium that causes the majority of US cases of Lyme disease. When ticks consume the blood of a vaccinated mouse, they cannot transfer the bacteria to humans or other animals.

“Mice are probably one of the most important reservoir hosts for Lyme disease,” according to disease ecologist Jean Tsao from Michigan State University. 

The conditional license for the mouse vaccine means it is available on request for about one year, with the possibility of renewal, for federal and state health authorities and other groups.

A human vaccine was on the market from 1998 to 2002, but was withdrawn due to low consumer demand that was likely related to fears over its safety. The human and mouse vaccines both use a protein called OspA to stimulate antibody production and prevent infection. 

Vaccines that target wildlife hosts like mice will remain one tool among many for managing Lyme disease risks. Other approaches include controlling tick populations by controlling deer populations and genetically engineering mice that produce B. burdorferi antibodies without the need for vaccination. A new vaccine for humans is also in late-stage testing in several thousand people.