Tick bites can transmit a variety of serious diseases, including Lyme disease. A specific germ causes this infection. It is a spirochete in the genus Borrelia. In the US, B. burgdorferi is usually responsible. In Europe, different species within the Borrelia genus cause Lyme infections. The germ is transmitted through the bite of a blacklegged tick, aka a deer tick (Ixodes scapularis). Even where clinicians think Lyme disease isn’t likely, people sometimes encounter a deer tick. Treating a bite promptly might help prevent Lyme disease.
Rates of Lyme Disease Are Rising:
Rates of Lyme disease have been rising dramatically in many parts of the country. That’s because the deer tick that carries the infection-causing bacteria is expanding its territory. Although it is most common from Virginia northeast and in the upper midwest, deer ticks now range throughout the eastern US.
How Can You Avoid the Disease?
The best way to prevent Lyme disease is to avoid being bitten by a deer tick. That, of course, is easier said than done. Whenever you are outside where there is vegetation, protective clothing and insect repellent can help discourage ticks. Permethrin-treated pants or gaiters are useful. Our anti-tick repertoire includes wearing long pants tucked into socks under gaiters. Exposed skin should be protected with an effective repellent. DEET, picaridin and oil of lemon eucalyptus all work.
Once you come inside, immediately removing outdoor clothing and checking the body for ticks is crucial. They like to hide in nooks and crannies, so examine those carefully. A shower can help you look yourself over, and has the added benefit of getting rid of any poison ivy or poison oak you might have encountered in the woods. Remove any ticks promptly with a tweezer. Experts believe that it takes ticks several hours to transmit a Borrelia infection.
Would a Vaccine Prevent Lyme Disease?
Veterinarians can vaccinate dogs to prevent Lyme disease, but there is no FDA-approved Lyme immunization for humans at this time. However, a collaborative effort by pharmaceutical giant Pfizer with the French drug maker Valneva may change that. The companies are conducting a 6,000-person phase-3 study of a Lyme disease vaccine (VLA15) in parts of the US and Europe where the disease is common. One reader asked about a vaccination against Lyme:
Q. When I contracted Lyme, my doctor diagnosed it early and treated me within days with doxycycline. I once read that there was a vaccine for Lyme disease available at one point. Because the source was online, I’m not sure it was reliable.
Is it true that there was once a vaccine? And is it also true that “it just wasn’t cost-effective to produce,” as it would only be used by a small portion of the population?
A. If you had a dog and lived where deer ticks are widespread, your veterinarian could offer a Lyme vaccine for your canine companion. Sadly, there is currently no human vaccine available. (We explain the history below.)
However, Pfizer and Valneva are collaborating to develop a new Lyme vaccine. Clinical trials report promising protection in both adults and children. The vaccine has not yet been submitted to the FDA for review, so it could be another year or two before doctors can prescribe it. Nonetheless, that could be a big help in regions where Lyme disease is endemic.
The History of Vaccine Against Lyme Disease:
The FDA approved LYMErix in 1998 to protect people from infection with the microbe that causes Lyme (Borrelia burgdorferi). Three shots provided 76 percent protection (Epidemiology & Infection, Jan. 2007).
Questions about vaccine safety at that time created tremendous controversy, not unlike today. Some people who developed arthritis following vaccination sued the drug company. Although the FDA concluded that the benefits far outweighed the risks, negative publicity resulted in very few people requesting the shot. As a result, in 2002 the manufacturer withdrew it.
Lyme disease infection can itself cause persistent, hard-to-treat arthritis, severe pain, neurological complications and heart damage. The CDC estimates that nearly 500,000 Americans contract Lyme annually. Perhaps we should revisit the potential value of a human vaccine against Lyme disease.
Antibiotics for Tick-Bite Rash:
Q. We moved from North Texas to a lake in East Texas. Within the first week of living here, my husband discovered a tick on his stomach. He pulled it out, and a week later we saw a bull’s eye rash as clear as can be.
I sent him off to urgent care, and he asked for a round of antibiotics. The clinic had not seen a tick bite or rash ever! That sounds unbelievable, since the Sam Houston Forest is all around us.
He took two rounds of antibiotic and the rash went away. Luckily, he has not had any residual effects. Don’t mess around with Lyme disease!
There’s Little Lyme Disease in Texas:
A. According to the CDC, Lyme disease is relatively rare in Texas. There are, however, cases reported every year. Your husband was smart to get treated promptly. In places where Lyme disease is common, unlike Texas, experts now recommend a single dose of doxycycline to treat a bite from a deer tick (Medical Letter on Drugs & Therapeutics, May 17, 2021).
Prevention is absolutely the best strategy against tick bites. Readers of this column have praised the benefits of wearing permethrin-treated gaiters that fit over shoes, socks and lower pants legs.
One person commented:
“The leading tick expert at the University of Wisconsin recommends wearing rubber boots (wellies) and says that ticks don’t like them at all. I spray my boots and pants with permethrin, and so far, so good. We have tons of ticks in our Wisconsin woods.”
Monoclonal Antibodies Under Development:
The University of Massachusetts Medical School, located in Worcester, Massachusetts, where Lyme disease is endemic, is working on a monoclonal antibody. Phase 1 trials are currently underway. This medicine takes the form of a shot to prevent ticks from transmitting Lyme disease pathogens through their bites.
What Should You Do After a Tick Bite?
For now, the best protection is a painstaking tick check whenever you come in from the garden or the woods. Perhaps by 2025, though, the vaccine study will have been completed and submitted to the FDA. If it is successful, there’s a chance of access to the Lyme disease vaccine for anyone over five years old. The monoclonal antibody is likely to require a longer time for development.
Most people wait until symptoms develop before seeking treatment. (In areas where Lyme disease is very common, doctors may treat as soon as a patient notices a tick bite. Such prophylactic treatment often requires only one-day dosing.) Wouldn’t it be great to have a way to prevent Lyme disease?
A Topical Treatment Against Lyme Disease:
Austrian researchers developed a topical antibiotic gel containing azithromycin (Lancet Infectious Diseases, Dec. 20, 2016 ). When applied to the site of the tick bite within three days, it can prevent Lyme disease infections. This could lead to a new way to prevent Lyme disease in the future.
In this study, more than 1,000 patients were randomly assigned to use the gel or a placebo every 12 hours over a period of three days. Of those who applied the antibiotic gel, none developed Lyme borreliosis. There were seven infections in the control group. The investigators reported no complications from gel use.
One difficulty with this approach is that a person needs to recognize a tick bite immediately. Deer tick nymphs that carry the germ are very small and may not be noticed right away. That is why it is crucial to do complete inspections of every part of the body after being in an area where there are ticks. The biggest drawback for American readers, however, is that azithromycin gel is not available for prescription in the US. Consequently, we cannot use it to prevent Lyme disease.
What Are the Consequences of Lyme Disease?
Although the diagnosis of Lyme disease is more sophisticated now than it once was, failing to treat it can lead to serious complications. Some people develop arthritis. Others have cognitive problems as a consequence of Lyme disease. That is why it is so important to prevent Lyme disease if at all possible. You may be interested in our interview with Neil Spector, MD, author of Gone in a Heartbeat. He described his multi-year odyssey that ended in a heart transplant. We interviewed Dr. Spector about his Lyme disease experience one more time before he passed away. Dr. Billl Rawls was also a guest on that interview, Show 1081: What Do You Need to Know About Lyme Disease?