Summer in Vermont is the season for fresh berries, sweet corn, glorious hikes, swimming in the lake, and, unfortunately, it is also a season to worry about developing Lyme disease.
Lyme disease is an infection caused by a bacterium called Borrelia burgdorferi. The bacterium is transmitted to humans through the bite of a deer tick. The first signs and symptoms of Lyme disease include fevers, muscle aches, headache, fatigue, and a typical red rash at the site of the tick bite. The rash is usually round, flat, larger than 5 cm in diameter and may have a central clearing. Without treatment, the infection can spread to the heart, joints, and even the fluid that surrounds the brain.
The good news is that the vast majority of patients diagnosed with Lyme disease are easily treated with common antibiotics and develop no long-term problems.
The best way to prevent Lyme disease is not to get bitten by a tick! That sounds a bit funny, but wooded and bushy areas with high grass and leaf litter are high risk areas. If venturing into such areas, use insect repellants. Insect repellants such as 20-30 percent concentrations of DEET (N, N-diethyl-m-toluamide) and picaridin are applied to both the skin and clothing and provide protection for several hours. Hikers and outdoor enthusiasts can spray their clothes (not skin) with a colorless odorless insecticide (.5% permethrin) which remains protective through several washings.
It turns out that it takes time for a tick to reliably transmit B. burgdorferi to humans – about 36 to 48 hours. That means frequent tick checks and removal of ticks early is an effective strategy for preventing Lyme disease. For example, if a person notices a tick on his or her right thigh Monday evening and is sure that it was not there Sunday, immediate removal will prevent Lyme disease. The CDC recommends bathing or showering as soon as possible after coming indoors to wash off and more easily find ticks.
Tick removal is straightforward: use tweezers to grasp the tick as close to the skin’s surface as possible and pull upward with steady even pressure. Sometimes a piece may be left behind. Don’t worry as this will heal. Wash the area with soap and water. A rash that develops in the next day or two is not due to Lyme disease, but usually due to local irritation. If the tick has been on your body for an unknown amount of time, transmission may have occurred. However, even in very high risk areas, the risk of Lyme disease from any deer tick bite is less than 5 percent.
So, enjoy the summer, but keep in mind that prevention is always the best strategy. If outdoors in tall grass or woods, remember to use insect repellants and do frequent tick checks.
William Raszka, MD, is a pediatric infectious disease specialist at the University of Vermont Children’s Hospital at the University of Vermont Medical Center and a professor at the Larner College of Medicine at UVM.