New Anti-Tick Vaccine Gives Hope for Preventing Lyme Disease
The quick spread of black-legged ticks that transmit Lyme disease affects around 40,000 known cases in the US per year, but researchers believe this number is several times higher in reality. According to a new study, scientists have now developed a vaccine that managed to prevent the onset of Lyme disease in guinea pigs.
For the tick to transmit the bacteria which triggers Lyme disease, it has to stay attached to the host for about 36–48 hours and cover the pathogen in its spit so that it could be transferred undetected due to the proteins that deplete the immune response of the host. The study’s authors decided to use the proteins from ticks’ and create mRNA—a gene molecule containing instructions on forming each of the selected proteins, which they later injected into the guinea pigs.
The mRNA then instructed their cells to generate antibodies and provide an immune response. This is the same principle applied in the design of Moderna and Pfizer vaccines against COVID-19. The vaccine prevents ticks from feeding once attached to the host, so they fall off before they manage to transmit the disease.
Scientists already knew that guinea pigs can gain natural immunity to tick bites after being repeatedly bitten, due to the immune response—the inflammation around the bite site. The tick bite area in vaxxed guinea pigs was significantly more swollen as opposed to the unvaccinated ones in which there was no substantial inflammatory reaction to be observed. Moreover, after testing the guinea pigs, researchers found the bacteria that causes Lyme disease in almost half of the unvaccinated guinea pigs, while the vaccinated guinea pigs didn’t test positive for it.
The findings of the study uncovered that quick removal of the tick, as well as the inflammation arising as a result of a tick bite, is key to developing an effective vaccine for preventing Lyme disease and possibly other pathogens carried by ticks. Despite the positive outcome of the study, it’s yet to be seen if the vaccine will apply to humans.
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