A Lyme vaccine — or something similar — is on the horizon

It’s the middle of tick season, in the heart of tick country. And when there are ticks, there are worries about Lyme disease. While there’s a Lyme vaccine for dogs, there isn’t one available for humans. But, that may change.

Our approach to Lyme disease may look very different in just a few years. Here's why — and what you need to know about this tick-borne illness right now.

Once upon a time, there was a Lyme vaccine. But 20 years ago, after just a few years on the market, it was discontinued. While the vaccine worked well — reducing Lyme infections by nearly 80% — some people said it caused concerning side effects like arthritis. That was never proven, but market pressure led the manufacturer to stop making the vaccine.

This month, a new Lyme vaccine entered the final stages of clinical testing. It’s made by Pfizer and another pharmaceutical company, Valneva. It uses a similar approach to the previous vaccine, but it’s been adjusted to leave out the protein region that caused the controversy before.

If all goes well, the companies could seek authorization for this new vaccine in 2025. But Massachusetts residents and others in Lyme-endemic areas can already sign up to be part of the trial.

It’s not just a Lyme vaccine that’s in the pipeline. There’s also something called a pre-exposure prophylaxis in the works. This is a treatment — in this case a monoclonal antibody shot — that would be given once a season to help prevent infection.

Mark Klempner, who spearheaded this research at MassBiologics of UMass Chan Medical School, said the fact that monoclonal antibodies have been used to help treat and prevent COVID has been helpful in smoothing the way for his work to be accepted.

“Maybe the world will be more receptive to a monoclonal antibody to prevent Lyme disease than they will be to a vaccine because there's so much vaccine antipathy,” he said. “But, one way or another, I'm hopeful that we will have a medicine in the next two years to prevent what is a very significant public health problem in the United States.”

This month, Klempner’s team is wrapping up a trial testing dosage and ensuring there are no nasty side effects from the monoclonal antibody. He said there are none, even at the highest dosage. The earliest it could be ready for the general public, he said, is 2024.

In addition to monoclonal antibodies for COVID paving the way for monoclonal antibodies for Lyme, the pandemic has impacted how we test, treat and think about Lyme disease for better — and for worse.

First, the bad.

Daniel Solomon, an infectious disease doctor at Brigham and Women’s Hospital, said people have become accustomed to at-home rapid tests with COVID. But he cautions against adopting a similar approach to at-home Lyme tests. Many of them are not approved by the Food and Drug Administration, and he says they don't work well early in a Lyme infection.

“While I think it's been really, really helpful to have these at-home COVID tests, the at-home Lyme tests aren't quite ready for prime time,” he said.

Now, the good.

There are some positive spillover effects from COVID. The pandemic has brought an infusion of resources and interested in long-COVID, and Solomon thinks that may help push forward research on Lyme disease, particularly post-treatment Lyme disease syndrome, or PTLDS. This is a syndrome that happens when a person has lingering symptoms — such as fatigue, brain fog and poor concentration — long after the actual infection clears up.

“That syndrome of post-treatment Lyme disease and what we are currently calling long-COVID have an unbelievable amount of overlap. These syndromes really look similar,” Solomon said.

His guess is that the underlying biology is similar and involves some sort of dysregulation of the immune system. Solomon is hopeful that research on long-COVID will offer insights that will be useful in treating people with PTLDS.

Before there is a Lyme vaccine or monoclonal antibody, the best approach to Lyme disease is vigilance about tick bites — take steps to avoid them!

State data suggests last year's tick population in Massachusetts was particularly bad. This year is shaping up to be in the normal or low end of normal range. However, ticks are still out there. They remain active all the way into late fall, and their range is steadily expanding because of climate change and other changes in their natural environments.

So check for ticks, and remove them after spending time outdoors. Many experts also recommend using bug spray or treated clothing to deter ticks.

If you do get a tick bite, the first thing to do is talk to a doctor. Antibiotics are effective at treating Lyme disease and can be taken after a bite as a preventive measure.

Solomon said this can be done within three days of a tick bite, but the earlier the better. "If people are bitten by a tick, if they take a single dose of doxycycline, it can dramatically decrease the risk of transmission of Lyme disease," he said, adding that research suggests it decreases the risk by as much as 87%.

Doctors report a fair amount of confusion about Lyme tests. So here’s the scoop: A Lyme test is actually an antibody test. It may not work well in the early stages of an infection because the body does not have enough antibodies to alert the test.

In the case of a recent potential infection, people can be treated just based on symptoms, including a bullseye rash, fever, fatigue and headache.

“If someone presents with classic early stage Lyme disease in Massachusetts in July, we shouldn't be relying on a test to guide treatment decisions," said Solomon.

Later in the course of the disease, when there are symptoms like joint pain, the body has had time to mount an antibody response, and the tests perform very well.