Lyme disease is a bacterial infection that ticks spread. In the United States, it occurs in thousands of people each year, and this number is on the rise. For researchers, the hunt for a safe, effective Lyme disease vaccine continues.
LYMErix, the first and last Lyme disease vaccine, received licensing and approval from the U.S. Food and Drug Administration (FDA) in 1998, but the manufacturers stopped selling it in 2002, due to a lack of demand.
Since then, research into the disease has continued, but a new vaccine has yet to appear on the market.
In this article, we look at the effects of Lyme disease, existing vaccination options, and research into newer vaccines.
A person contracts Lyme disease through the bite of a black-legged tick that is infected with B. burgdorferi bacteria.
Also called Lyme borreliosis, the disease is the most common tick-borne illness in the U.S.
In 2018, U.S. Centers for Disease Control and Prevention (CDC) estimated that, while around 30,000 cases of Lyme disease are reported each year, the real number of people diagnosed with the condition may be closer to 300,000.
According to the CDC, medical centers in the U.S. reported 26,203 confirmed diagnoses of Lyme disease in 2016. The same year, they also reported 10,226 probable diagnoses.
Many people do not report Lyme disease, but based on these figures, doctors diagnosed 36,429 cases of Lyme disease during the year.
Early symptoms of Lyme disease appear 3–30 days after a bite from an infected tick.
Early symptoms can include:
- flu-like symptoms, such as swollen lymph nodes, fever, chills, and fatigue
- a rash, possibly with a bull’s-eye pattern
Whether or not it has the classic pattern, a rash appears in 70–80 percent of people with Lyme disease.
Within several days or months of infection, a person may also experience:
- severe headaches and a stiff neck
- arthritis, with severe pain and swelling in the large joints
- pain in the tendons, muscles, bones, and joints
- nerve pain
- shortness of breath
- tingling, numbness, shooting pains, or a combination, in the hands or feet
- memory problems
- irregular heart rhythms
- inflammation in the brain and spinal cord
- facial palsy, which is a loss of muscle control in part of the face
Taking steps to avoid tick bites can help prevent Lyme disease, and antibiotics can treat it.
However, serious complications can arise if people do not receive treatment or if they do not receive it early enough in the disease’s progression.
Only one vaccine has been available to the public. Researchers are now developing improved vaccines that work by other means.
In the 1990s, GlaxoSmithKline — then called SmithKline Beecham (SKB) — developed the LYMErix vaccine to protect against Lyme disease.
Researchers developed the vaccine to boost the production of antibodies that combat a protein on the cellular surface of the B. burgdorferi bacterium. The targeted protein was called outer surface protein A (OspA).
Ideally, if a tick bit a person who had received the vaccine, blood full of antibodies would enter the tick and kill the bacteria. This would occur before the tick could pass the bacteria to the person.
The LYMErix vaccine went through phase III clinical trials and received FDA approval in 1998.
According to the National Institute of Allergy and Infectious Diseases, it was 76–92 percent effective in preventing Lyme disease after three injections.
In December 1999, a group of 121 individuals filed a lawsuit. They stated that they had experienced a range of significant adverse reactions to the vaccine, including musculoskeletal issues, such as arthritis.
The FDA investigated and found no evidence that LYMErix was causing harm, but production ceased in 2002, due to a lack of demand.
Around the same time, another company, Pasteur Merieux Connaught, was developing a vaccine that worked similarly, by targeting OspA.
The vaccine, called ImuLyme, also went through phase 3 clinical trials, but the company decided not to apply for regulatory approval. They did not give a reason.
After SKB withdrew LYMErix from the market, Professor Erol Fikrig of Yale University School of Medicine — who had helped to develop the vaccine — tried a different approach.
Prof. Fikrig and his team focused on the tick’s saliva. They found a way to block transmission of B. burgdorferi, and possibly other harmful bacteria, in mice.
In 2009, Dr. Fikrig and his team published their findings in Cell Host & Microbe. They hoped that these could help others to develop a new vaccine for Lyme disease and further means of protection from insect-borne illnesses.
In 2013, researchers from Stony Brook University, Brookhaven National Laboratory, and the company Baxter International published the results of their trials involving another vaccine that targeted OspA.
During trials in Germany and Austria, the team gave the vaccine to 300 participants. There were only a few mild adverse reactions and no serious side effects.
In 2015, MassBiologics, a non-profit vaccine manufacturer linked to the University of Massachusetts Medical School presented its research on pre-exposure prophylaxis.
This type of injection could provide seasonal protection for 6 months, to cover the period in the year when the ticks are active. The researchers hoped to use their findings to develop extended forms of protection.
In mice, short-term solutions appeared promising.
In 2015, Dr. Richard Marconi, a microbiologist and vaccinologist at Virginia Commonwealth University, and his team were working on a vaccine that targets outer surface protein C (OspC), which is similar to OspA.
This vaccine would not need the repeated booster injections that the OspA vaccine required to stay active.
By 2015, Marconi’s team had already licensed a vaccine to protect dogs from the disease.
In 2017, a team of researchers published their findings of a study in mice. They concluded that a drug called VLA15 could protect against six different types of bacteria that cause Lyme, including the main type in the U.S.
While developing the vaccine, the team have focused on ensuring that it will not cause the kind of immune system reactions that led to the withdrawal of the first vaccine.
For the vaccine to be approved for use in humans, further research is needed. However, there is hope that a safe, effective Lyme vaccine will one day be available.
Until there is a vaccine, people should take care in areas where there are ticks.
Preventive measures include:
- knowing which areas ticks are likely to inhabit
- knowing the symptoms of Lyme disease, such as a rash and a fever
- using insect repellant on the skin or on clothes
- checking for ticks regularly
- removing any ticks with fine-tipped tweezers
The CDC note that if a tick is on the body for less than 24 hours, it is unlikely to pass on Lyme disease.
How do I remove a tick?
In the event that you find a tick somewhere on your body, do not panic, and focus on removing the tick as soon as possible. Follow these simple steps, recommended by the CDC, to safely and quickly remove the tick:
- Using a pair of fine-tipped tweezers and as close to the surface of your skin as possible, grab the tick gently and slowly.
- Pull the tick upward with the tweezers using steady, even pressure. Be careful not to twist or jerk the tick as this can allow the mouth of the tick to remain attached to the skin.
- After removing the tick from the skin, clean with rubbing alcohol or soap and water the area the tick was biting. Wash your hands also.
- Do not crush a tick with your hands or fingers. To dispose of a tick after removal, place it in alcohol, in a sealed bag/container, wrap it in tape, or flush it down the toilet.