Q: How is Lyme disease transmitted?
Lyme disease is typically transmitted through the bite of a tick (the vector), although many researchers now believe that it is also transmitted through other insects, including mosquitoes, mites, biting flies, and fleas.
Once a host is bitten by the tick, Borrelia spirochetes and often other organisms, such as Babesia, Bartonella, Mycoplasma and/or Ehrlichia pass through the saliva of the tick or other insect and enter the bloodstream of the host. If it is not removed, the tick can continue to feed for several days, during which time it ingests the host’s blood as well as any blood-borne pathogens the host may carry.
Although the CDC maintains that ticks are the only vectors of Borrelia, Borrelia spirochetes have been found in 30 species of arthropods (hard-shelled insects), 13 species of mites, 15 species of flies, as well as fleas and mosquitoes. While these insects serve as reservoirs for Borrelia, the research community has not yet found solid evidence that they can transmit the disease. (There are, however, anectodal reports of patients contracting Lyme from biting flies.)
Q: Can I give Lyme disease to my partner?
Sexual transmission of Lyme disease is something that should raise immediate public health concerns. Unfortunately, very little research has been done in this area but ample anecdotal evidence and doctors’ experiences with their patients seem to prove that sexual transmission is likely.
In April 2001, Dr. Gregory Bach gave a paper at the International Scientific Conference on Lyme Disease in which he presented finding among sexually active patients in which only one partner had a history of Lyme exposure. He found Lyme DNA sequences in 40% of the semen samples of Lyme patients, as well as in semen samples of male partners of female Lyme disease patients. All of the partners of subjects with Lyme-positive semen or vaginal secretions tested positive for Lyme disease.
A recent study by Middelveen et al. (2015) found spirochetes in cultures of genital secretions from 11 of 13 subjects diagnosed with Lyme disease. Motile spirochetes were detected in genital culture concentrates from 12 of 13 Lyme disease patients. The authors concluded that “The culture of viable Borrelia spirochetes in genital secretions suggests that Lyme disease could be transmitted by intimate contact from person to person.”
In a paper published in Medical Hypotheses in 2003, Drs. Harvey and Salvato found large numbers of chronically ill Lyme disease patients in Houston, Texas, a non-endemic area. After analyzing the evidence, the authors proposed that “there are at least two similar and unified, but distinct forms of human B. burgdorferi infection: ‘Lyme disease’, and ‘Epidemic Borreliosis’ (disease spread directly between humans).” Given the rapid global spread of Lyme disease their hypothesis is one which merits serious consideration.
Q: Can I give Lyme disease to my unborn child?
Sadly, there are numerous cases of transmission from a pregnant mother to a fetus. Mothers who contract the infection during pregnancy run the risk of stillbirths and miscarriages. Babies who survive to term may be born with congenital defects that cause death in early infancy, or that lead to significant disability. While some physicians dispute the existence of congenital Lyme disease, the fact that babies can be born with active borreliosis has been verified by autopsies of newborns who die shortly after birth.
According to a study conducted by Dr. Peter A. Schlesinger et al. in 1985, 66.7% of untreated mothers with Lyme disease had pregnancies with adverse outcomes. These included cardiac problems (22.7%), neurological defects (15.2%), orthopedic problems (12.1%), genitourinary problems (10.6%), as well as many other anomalies. Mothers with active Lyme disease acquired before the first trimester had the highest rate of adverse outcomes (72.7%).
Although the CDC maintains that “no negative effects on the fetus have been found when the mother receives appropriate antibiotic treatment” there is still risk even when the mother is treated. 14.6% of the pregnancies with adverse outcomes in the Schlesinger et al. study were among treated mothers.
There are also risks associated with co-infections. Mothers who are infected with bartonella as well as borrelia may pass the infection on to their unborn children.
Q: How do I prevent Lyme disease?
Ticks are crawling insects. They do not jump or fly, and although they may be brushed off onto low branches by deer or other mammals, they are most commonly found in grass and low vegetation. Ticks are particularly fond of moist areas, such as grassy meadows, piles of leaves, and woodlands.
Infection from tick bites can be prevented by wearing long pants when outdoors, and tucking socks inside pant legs. Either spray repellent around the feet and shins, or, in the case of children, use natural repellents. Wear a long-sleeved shirt and tuck your shirt into your pants. Wear a hat, and tuck in your hair. Light-colored clothing makes it easier to spot ticks. Make sure to inspect your whole body when you return home. It is especially important to inspect children carefully when they come indoors, as small children can harbor ticks on the neck and head.
If you have a lawn, keep it mowed very short to allow the moisture to evaporate. Remove leaves and piles of brush. For those who live in dry areas, such as California, it would be prudent to remove grass lawns entirely, substituting them with drought-resistant plants and gravel.
Ticks have an aversion to the strong-smelling members of the mint family, as do deer. Some people in the damp northeast have eliminated ticks from their yards by planting mint in their lawns. When the mint is mowed it releases oils that are natural repellents. Using members of the mint family, such as catnip, to line garden borders can also help repel ticks. If you have pets, make sure to check them thoroughly for ticks before allowing them indoors.
For more information on how to control ticks, the Connecticut Agricultural Experiment Station in New Haven provides a free guide: Tick Management Handbook: An integrated guide for homeowners, pest control operators, and public health officials for the prevention of tick-associated disease.
Q: What do I do if I am bitten by a tick?
If you are bitten by a tick, remove it as soon as you can. The longer the tick remains attached, the more time it has to release bacteria.
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- Use fine tweezers to grasp the tick as close to the skin surface as possible.
- Pull backwards gently but firmly, using an even, steady pressure. Do not jerk or twist.
- Do not squeeze, crush, or puncture the body of the tick, since its bodily fluids may contain infection-causing organisms.
- After removing the tick, wash your hands thoroughly with soap and water. Clean and disinfect the area around the tick bite.
- Place the tick in a sealed jar and take it to your physician or a lab. The tick can be analyzed for the presence of spirochetes and other bacteria. Label the container with your name, and time and date of the bite.
If you cannot reach your physician, many state and local health departments, especially in areas where ticks are endemic, keep lists of labs where ticks can be tested. Here are some resources for finding a lab:
When to get a tick tested (California)
Mainely Ticks (New England and New York)
Q: How do I know if I have Lyme disease?
Lyme disease is the great imitator. Early in the disease, it can look like a flu, with headaches, fatigue, and achiness. The rule of thumb when you have new symptoms is to not assume it’s nothing serious, especially if you live in a Lyme endemic area. Even if you don’t remember having been bitten by a tick, and don’t have a rash, the appearance of new symptoms – especially headaches, vision problems, sleep disturbance, difficulty performing mental tasks, and joint pain – should be brought to the immediate attention of your physician. The earlier Lyme disease is treated, the easier it is to cure.
Q: What happens if Lyme disease is not properly treated?
Lyme disease does not resolve on its own. Even if you remain asymptomatic for months, or are in a period of remission, Lyme disease can eventually become disabling. Over time, as the spirochetes travel through different organ systems, the array of symptoms becomes increasingly complex, which is why so many physicians have difficulty diagnosing it.
The progression to neuroborreliosis is particularly problematic because once the infection reaches the brain it is harder to treat. People with advanced Lyme disease can develop a form of dementia that resembles Alzheimer’s, which in older patients leads to misdiagnoses, further delaying treatment.
Q: Is Lyme disease a new disease?
Although Lyme disease only came to public attention in the 1970s, there is evidence that the Lyme spirochete has been around for a long time. In Europe there are documented cases of infection by Borrelia going back to the 1800s, and in the U.S., Borrelia spirochetes were found in a 107-year-old mouse pelt in the Harvard Museum of Comparative Zoology. The mouse specimen was collected in a town near Old Lyme, Conn.
According to a genetic study conducted by Hoen et al. (2009), Borrelia burgdorferi has been present in the United States for thousands of years. The authors proposed that the recent emergence of Lyme disease has been driven by the 20th century reforestation of areas that had been previously cleared for agriculture and grazing. When deer populations declined, so did the spread of ticks. However, some herds remained on Long Island, New York, in islands of Massachusetts and in the Midwest. These herds harbored the ticks that were infected with Borrelia burgdorferi. The recent increase in the deer population as well as human expansion into suburbs close to woodlands have combined with animal migration to aid the spread of the disease.
Q: Is there a vaccine for Lyme disease?
Currently, there is no vaccine for Lyme disease.
Gregory Bach, DO. Recovery of Lyme spirochetes by PCR in semen samples of previously diagnosed Lyme disease patients. International Scientific Conference on Lyme Disease, April 2001
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Last Updated: 4/22/15
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