Fighting Lyme on All Fronts
The story of Lyme disease vaccines has been long and convoluted. There used to be a vaccine, and it was commercialized, but its manufacturer discontinued it because people didn’t really see the need to get vaccinated against Lyme.
That was 21 years ago, and climate change has set us on a different path. As the ticks that give Lyme spread across territories — with a quarter to a third of them actually infected with the bacterium that causes Lyme — people are now clamoring for ways to protect themselves. For pharmaceutical companies, the race is on.
Thing is, you don’t protect yourself against bacteria the same way you vaccinate against viruses, and the scientists are getting creative.
I say “race,” but there already seems to be a winner. Pfizer, of BioNTech fame, and Valneva, a French company that has made vaccines against cholera and Japanese encephalitis, are now testing a jab on about 6000 humans, adults and children. By targeting a protein on the surface of the Borrelia (the culprit for Lyme), this vaccine works by preventing the bacteria from leaving the intestines of the ticks. If the trials confirm that it’s safe and effective, the vaccine may go to market in the next few years.
Meanwhile, MassBiologics has come up with a PrEP, but for Lyme. Their monoclonal antibody would work like a seasonal Pre-Exposure Prophylaxis. You’d get the jab each year before you wander into the woods, a bit like we do with the flu shot each autumn. This may be a good solution for fair-weather campers like me. The only thing is that now, due to warmer weather, ticks are out partying year-round.
But what if you could instead get inside the tick’s gut and tweak its microbiome? This is what a third group of scientists are trying to do. The INRAE — France’s institute for research on agriculture, food, and the environment — team is betting on a Trojan Horse strategy. Here’s how it works: you take a harmless bacterium and you inject it into a mouse. The mouse’s immune system starts making antibodies against it — antibodies that happen to be good at fighting Borrelia. The mouse then gets bitten by a Borrelia-carrying tick. The mouse’s blood goes into the tick and the antibodies start to attack Borrelia. Check the tick’s tummy a while later, and boom: the tick’s microbiome looks completely different and Borrelia are mostly gone.
Mind you, this shot does not stop the mouse from catching Borrelia. But imagine vaccinating woods-dwelling mammals with this thing, and protecting humans with one of the other two solutions. You’d be fighting Lyme on several fronts. Plus this could open up new ways to fight other diseases carried by insects, like malaria.
Since we can’t be bothered to change our habits to stop climate change, humans are at least ingenious enough to find new weapons against illnesses associated with it. Even if it means enlisting bacteria to fight other bacteria.