A new Lyme vaccine is 100% effective in tests

There is already a substance that can be used to make a vaccine against Lyme disease, a tick-borne illness caused by bacteria of the genus Borrelia. But the vaccine was developed against a strain of bacteria found only in America. It has not yet been possible to protect against the disease by vaccination in Europe. Parasitologists from the Biology Centre of the Czech Academy of Sciences in České Budějovice have now tested a promising substance whose effectiveness against Borrelia in trials has been 100%.

The vaccine was developed by American pharmaceutical concern Sanofi, and Czech scientists from the Institute of Parasitology of the Biology Centre of the Czech Academy of Sciences (BCAV ČR) chose it for testing on the European tick Ixodes ricinus. The new vaccine follows on from the previous American vaccine. “The first Lyme disease vaccine was based on a borreliosis surface protein in a tick called OspA. It was a simple molecule that had a number of side effects. It only it covered only one species of Borrelia, so it was usable only in America, where this type of Borrelia occurs in ticks,” parasitologist Radek Šíma from BCAV ČR said in a press release.

Currently, 21 species of Borrelia bacteria are known. They have different surface proteins, and these surface proteins change when the bacteria move from a tick to the human body. The pharmaceutical company improved the structure of the vaccine by creating the core of a molecule that various OspA surface proteins can be bound to. “This new structure allows the immune system to quickly and reliably recognize a foreign substance in the body and make antibodies against it. It is a vaccine against the transmission of Borrelia, it works very quickly, as soon as Borrelia passes from a tick to a human,” Šíma said. The immune system, which is trained by the vaccine, immediately detects Borrelia in the body and eliminates it. “In addition, the fundamental innovation of the vaccine is that it targets all types of Borrelia,” Šíma said.

Analysis in the laboratories of the Institute of Parasitology of the BCAV ČR showed 100% effectiveness of the vaccine on the European tick Ixodes ricinus. Researchers tested the substance on mice, now it will depend on whether the pharmaceutical company invests in a clinical trial of the vaccine in humans. After that, the vaccine could be prepared for the market.

Lyme borreliosis is an infectious disease whose first symptom is a red spot with a fading center around the tick's bite. It can also be manifested by fever, muscle pain or fatigue. However, these flu-like symptoms may not always occur. The disease is treated with antibiotics. If left untreated, it affects the nervous system, heart or joints. Unlike tick-borne encephalitis, the second major disease from ticks, it is not yet possible to get vaccinated against Lyme disease.

Publication:

Kamp H.D., Swanson K.A., Wei R.R., Dhal P.K., Dharanipragada R., Kern A., Sharma B., Šíma R., Hajdušek O., Hu L.T., Wei Ch.-J., Nabel G.J. (2020) Design of a broadly reactive Lyme disease vaccine NPJ Vaccines 5: 33. DOI: 10.1038/s41541-020-0183-8.