Why Isn’t There a Lyme Disease Vaccine?
Blame its bacteria’s weird protein structure.
For 25 years, Heather McKean has experienced uncomfortable, unexplainable health issues. Since she was five years old, the 30-year-old has lived with everything from migraines to sinus infections, gastrointestinal issues and chronic fatigue. It wasn’t until June of 2017 that she finally received a diagnosis that made sense of it all: Lyme disease.
“I went from being really excited to having a diagnosis to, like, of course I get the diagnosis that’s really hard to treat,” she told The Daily Beast.
What makes it worse is the fact that there are no vaccines to help fight it.
Lyme disease is an infectious disease caused by the bacterium Borrelia burgdorferi. The disease is known to be difficult to diagnose, as many early symptoms are vague, like headaches and fatigue.
In its earliest stages, Lyme can be combated with antibiotics—but that’s if it’s recognized early. The longer it takes to treat Lyme, the more likely it is for it to become a chronic disease, like McKean’s.
Which makes it even more odd that a vaccine for Lyme disease doesn’t exist, particularly because cases are spiking. Earlier this month, the CDC reported that many vector-borne infections are not reported or recognized, making it difficult to estimate the cost and burden of these diseases. “We know that the number of Lyme disease cases that actually occur each year are approximately 300,000, or 10 times higher than what is nationally reported,” Lyle Peterson, Director of CDC’s Division of Vector-Borne Diseases, said in May on a press briefing call, also reporting that Lyme disease makes up 82 percent of all tick-borne diseases.
So will there ever be a vaccine?
“There was a vaccine on the market in 1998 and for a variety of reasons, that vaccine failed and was pulled. As a result, it soured the market in big pharma’s interest in moving forward,” Richard Marconi, a Virginia Commonwealth University professor in the department of microbiology and immunology, told The Daily Beast.
That vaccine, called LYMERix, targeted Lyme’s outer surface protein A (OspA), and was not available to use in people under the age of 15. Even though 1.5 million people used the vaccine in 1999, public trust of the vaccine dissipated for various reasons including the rise of anti-vaxxers, a study citing that the vaccine could cause arthritis in hamsters and a class action suit against the vaccine’s manufacturer.
But Marconi said that the tide is turning when it comes to developing a new vaccine for Lyme.
“A couple things have happened that have turned the tide, and one of those is a much better understanding of the incidence of Lyme in humans,” he said. “We know it’s a much greater problem than had been appreciated in the past two decades, and we know that the ticks that transfer Lyme disease are spreading at an alarming rate, and we’ve actually gotten tremendous support from the National Institutes of Health and private foundations like the Cohen Foundation and The Global Lyme Alliance.
“So, yes, there has been difficulty moving forward, but I think we’re at a turning point.”
The FDA requires three phases of clinical trials before a vaccine is approved, with further trials once the vaccine is on the market, and Marconi said he’s optimistic a new Lyme vaccine should move to phase I clinical trials soon. The complication in creating this vaccine comes in the form of many different proteins in Lyme disease.
“What we’re doing is utilizing the important parts of proteins produced by very divergent and different strains of Lyme disease that exist in nature,” Marconi said. “That has been the challenge in Lyme disease. It’s relatively easy to make a vaccine to kill a limited number of strains, but we want one that can kill all of the strains.”
Brian Kidd, a Mt. Sinai researcher in genetics and genomic sciences, told The Daily Beast that Lyme researchers are working on genotyping different strains of bacteria to move toward more personalized diagnoses and treatment.
Kidd said researchers are using data to identify what genetics can make someone more susceptible or even resilient to Lyme and what that means for future prevention and vaccinations.
“Who are the individuals who are exposed to ticks, the bacteria causing Lyme, and yet not exhibiting any symptoms? So we think they’re infected but they don’t get sick and how does that compare to a complementary cohort of individuals who are also exposed and then start exhibiting symptoms?” he said. “So we’re trying to tease out and see if there’s a genetic background that puts them at risk or makes them more resilient or are there other factors that are not necessarily genetic.”
Still, Kidd explained, it’s an evolutionary arms race.
“It’s not as though the bacteria and the ticks remains static, strains can change and new ones come up and as that evolves and the pathogen landscape changes, scientists are constantly discovering new things and adapting to that,” he said.
He’s hopeful, though, as is Marconi, that better prevention and treatment is on the horizon. Marconi said he hears from patients living with chronic Lyme who feel extremely frustrated with the lack of care available to them.
“I think it’s important for people who are suffering with or living with the fear of Lyme disease to really have some faith and know that the tide is really changing, partly because of our vaccine work and better diagnostics and work of all scientists in the field who’ve really recognized the magnitude of the problem,” he said. “I think a lot of folks often feel they’re being left behind. I can honestly tell you that they’re not. We are all working really hard to putt this problem behind us and I think we will but it takes time.”
In a perfect world, Marconi said, a vaccine will come to market in about five years—barring any complications, of course, which can be frequent in the world of vaccine trials and approval. Until then, understanding risk and taking precautions to protect from tick bites, is doable.
Nancy Troyano, entomologist and director of technical education and training for the pest control service Rentokil Steritech, said while ticks are more active in warmer weather, they can still be active on winter days above 45 degrees. A big misconception is that ticks are too small to see, Troyano said.
“Although nymphs (the younger life stage) are tiny—about the size of a poppyseed, they are still visible. They look much like a ‘walking freckle,’” she said.
Basic precautions against ticks, especially when outdoors or hiking, include wearing long pants, tucking pants into socks, wearing light clothing so you can spot ticks crawling on you and wear insect repellents with an EPA-registered active ingredient, such as 20-30 percent DEET. Then, do a full-body check and bathe or shower within two hours of returning from outdoors.
If you’re bitten by a tick, remove it as soon as possible by grasping the tick by its head (the closest part to the skin). If you grab it by its fattest part, it could release more pathogens into the skin. Then save the tick for your doctor, which could help diagnose you down the line if you’ve contracted anything—until a vaccine comes along, of course.