A vaccine to prevent Lyme disease infection was briefly available in the 1990s.
Lyme disease is the fastest-growing vector-borne (bug-transmitted) infection in the United States today, according to the Centers for Disease Control and Prevention (CDC), and stopping the spread of the disease is difficult.
In fact, in 2017, the confirmed number of cases of Lyme disease was over 29,000Trusted Source, a 13 percent increase from 2016. Another 13,000 were probable cases of the infection.
Compare that to a decade before, in 2006, when almost 20,000 cases of the illness were confirmed.
Lyme disease is contracted by humans through tick bites, and today tick populations are booming.
In turn, so are the number of Lyme disease cases and incidence of other tick-borne diseases.
Researchers know how to prevent a Lyme disease infection: Avoid ticks that carry the disease.
Pet owners can protect their animals with flea and tick collars and medicines, and the United States has vaccines approved for use in dogs and horses.
But for people, avoiding ticks is a bit harder. You can wear clothing treated with the insecticide permethrin. But a human Lyme disease vaccine is nowhere to be found.
Researchers are trying to change that with a potential new vaccine currently in testing.
A new option to stop Lyme disease
Tick populations show no signs of shrinking and the spread of tick-borne illnesses are likely to continue increasing, so a Lyme disease vaccine could be big business.
Wendy Adams, research grant director at the Bay Area Lyme Foundation, said the real number of Lyme disease cases is likely much higher than the reported number.
“Due to reporting requirements, only about 30,000 cases are reported to health authorities, which the CDC has acknowledged is likely less than 10 percent of actual cases,” Adams said. “There are 329,000Trusted Source or more new cases of Lyme disease diagnosed each year in the U.S.”
That puts new cases of Lyme disease higher than almost any other reportable infectious disease, including HIV and AIDS.
“Different groups suggest that the global market for a vaccine against Lyme disease is estimated at approximately $1 billion annually, based on current estimates of the cost of treating patients with acute and more chronic Lyme disease,” said Mark Wooten, PhD, professor of medical microbiology and immunology in the College of Medicine and Life Sciences at The University of Toledo.
With that in mind, in 2017, the Food and Drug Administration approved a Fast TrackTrusted Source designation for a new Lyme disease vaccine.
French company Valneva’s vaccine for Lyme disease, VLA15, completed initial trials in early 2018 and is currently in phase II of clinical testing, Thomas Lingelbach, the company’s CEO, said.
“With the result of both phase II clinical studies [projected in mid-2020], we expect that we will have determined the optimal dosage level and schedule for use in VLA15 phase III efficacy testing,” Lingelbach said. He added that the vaccine is still four to five years away from potential vaccine licensure.
“It’s important to remember that the development of vaccines is measured in years, so it will be some time before this vaccine, if successful, makes it to the general public,” said Dr. Amesh A. Adalja, a senior scholar at Johns Hopkins Center for Health Security. “It appears promising and is the leading candidate vaccine.”
While researchers furiously work toward developing a new Lyme disease vaccine, many people in the United States may be surprised to learn that 20 years ago a Lyme disease vaccine was available in this country — and it worked.
Why the original Lyme disease vaccine disappeared
“The vaccine LYMErix was developed by SmithKline Beecham [now GlaxoSmithKline] and licensed in the 1990s,” said Meghan May, PhD, associate professor of microbiology and infectious diseases at the University of New England College of Osteopathic Medicine in Biddeford, Maine.
While the vaccine was designed as a three-dose medicine, researchTrusted Source showed the vaccine was 49 to 68 percent effective at preventing Lyme disease with two injections. After the third and final injection, that number jumped to 76 to 92 percent.
But despite this success, LYMErix didn’t last long. In fact, it was pulled from the market just a few short years after it was introduced over fears about side effects and subsequent lawsuits.
Soon after LYMErix was available to consumers in the 1990s, it fell under a shadow of suspicion.
Reports surfaced that a few patients who had received the Lyme disease vaccine had developed arthritis. Members of the media also picked up on these reports and warned consumers there might be a connection, despite a lack of research or verified evidence.
“Within a year, reports suggested that a small number of vaccinated people were experiencing side effects,” May said.
In 1999, a class action lawsuit was filed against the drug company by 121 people who had received the vaccine and had developed arthritis. They claimed the vaccine caused harmful side effects and that the pharmaceutical company was hiding the evidence.
Around the same time, an infamous study in the journal The Lancet connected another type of vaccine with autism. That autism study has since been proven false and retractedTrusted Source, but it helped fuel an anti-vaccine movement.
The media reports about the Lyme disease vaccine added to the hesitation, and people began to avoid LYMErix.
In April 2002, the company announced that sales for LYMErix had fallen from 1.5 million doses in 1999 to about 10,000 expected for that year. That was despite cases of Lyme diseases being on the rise. The company stopped producing and selling the vaccine that year.
“Unfortunately, the vaccine received a great deal of negative public and media attention,” said Dr. Alexea M. Gaffney-Adams, a physician who is board-certified in infectious disease, internal medicine, and pediatrics at Stony Brook Medicine.
After the company pulled the vaccine, the FDA conducted several additional tests to verify or refute the lawsuit’s claims. It was unable to replicate the adverse events and side effects that opponents of the vaccine reported in the lawsuit and elsewhere.
“The company settled the class action suit based on economic concerns for a product showing poor performance in the market,” Gaffney-Adams said.
“The final agreement included $1 million in legal fees but provided no financial compensation to the supposed vaccine victims.”
Despite LYMErix still being approved and licensed in the United States and the existence of studies to refute the claims of side effects, GlaxoSmithKline has never reintroduced LYMErix.
Why Lyme disease is hard to treat
Lyme disease, which is caused by Borrelia burgdorferi bacteria, is a tick-borne illness. It doesn’t circulate in the blood like many bacterial infections.
Instead, it hides in your body’s tissues. That makes it more difficult to detect and harder to treat.
If an infected tick bites you, you may begin to show signs of Lyme disease in one to four weeks.
“Primary Lyme disease is what most of us are familiar with,” May said. “The symptoms include fever, fatigue, body and joint aches, and in some cases, the characteristic ‘bulls-eye’ rash where red rings appear around the site of the tick bite.”
If caught early, Lyme disease can be treated with antibiotics.
If it’s not caught, untreated Lyme disease may progress and become a bit more serious.
“Secondary Lyme disease can include swollen or painful joints, extreme fatigue, numbness, headaches, muscle weakness, conjunctivitis, poor memory, confusion, and heart palpitations,” May said.
If it’s still not diagnosed at this stage, the bacteria may invade the central nervous symptom and cause problems, such as mental status changes and effects on mood, sleep, and memory, May said.
“Loss of muscle control, [muscle] tics, a lack of coordination, and potentially deadly heart complications” are also possible, she added.
Today, 90 percent of cases of Lyme disease are reported in just 14 states, according to the CDC. The majority of these states are in the Middle Atlantic region (Pennsylvania and New Jersey lead the way) and New England.
That doesn’t mean other states don’t have Lyme-infected ticks, however.
Ticks thrive in warm weather and spring and summer days. In warmer climates, tick season may stretch into fall and even winter.
That’s problematic because tick populations are on the rise, and warmer weather patterns extend the length of time when ticks might be active.
“One thing that is very clear is that we can reduce or avoid these complications by either preventing infection, such as with a vaccine or by preventing tick bites, or by making sure that patients are treated as early and aggressively as possible,” May said.
In the fight against Lyme disease, treatment and prevention go hand in hand as scientists look for ways to stop the slow climb of cases and prevent long-term complications.
The bottom line
As cases of Lyme disease increase in the United States, researchers are investigating a potential vaccine to prevent the tick-borne illness.
Currently that vaccine is in phase II testing and could be available in a few years.
But this would actually be the second Lyme disease vaccine released in the United States.
The original vaccine, dubbed LYMErix, was introduced in the late 1990s before being pulled due to claims of side effects.
While those side effects weren’t replicated by the FDA, the company stopped producing the vaccine in 2002.