By Dr. Adam Aronson
While the warm weather often signals the end of cough and cold season – families must be watchful for infections carried by mosquitoes and ticks – such as Lyme disease and West Nile virus. Know the signs and symptoms of these infections, how they are transmitted, and strategies to prevent exposure.
Thousands of cases of Lyme disease have been reported since it was first recognized in 1975. The infection is caused by a type of bacteria called a spirochete. It is transmitted to humans by the bite of infected deer ticks – tiny, black-brown insects about the size of a poppy seed. Infected deer ticks have been found in many parts of the United States – especially the northeastern states, California, and closer to Chicagoland in Michigan, Minnesota, and Wisconsin. Deer ticks live in forests or grassy, wooded areas and are most active from late spring through early fall. People have been exposed and infected during all types of outdoor activities from camping or hiking in secluded forests to their own backyard.
The first and most obvious symptom is a classic rash that looks like a target – with a red spot surrounded by a light pink ring. The rash typically develops within the first few weeks after the person is infected. It may expand over time and is usually not painful or itchy. Many people will also develop other symptoms such as fever, headache, swollen glands, fatigue and muscle or joint pain.
Lyme disease can be easily treated with a course of antibiotics, and patients will recover fully. If not recognized and treated, the infection can progress to more serious complications such as arthritis, meningitis, and paralysis of facial nerves.
Families traveling to or spending time in areas where deer ticks are prevalent should take note of the following strategies that have been shown to decrease the chance of exposure. Whenever possible people should stay on cleared paths and avoid the shaded, moist, wooded and grassy areas where the ticks prefer to live. Using insect repellent with DEET is also very effective. These products are safe even for children when they contain no more than 30% DEET and are washed off with soap and water when returning indoors. Children and adults should wear enclosed shoes or boots, and keep arms and legs covered. Wearing a hat can protect the scalp. Additionally – people should wear light colored clothes to make it easier no notice and ticks. The most effective way to prevent infection may be doing a complete tick check after returning indoors. Humans are usually infected when the tick has been attached for more than 48 hours – so prompt removal of ticks is critical.
If found attached to a person, the following steps will aid in removal. Fine tipped tweezers can be used to grasp the tick as close to the skin as possible. Try not to squeeze the body of the tick. Pull back slowly and the tick will usually release. The area should then be cleaned with alcohol or antibacterial ointment.
West Nile Virus
Since the first outbreak of West Nile Virus in 1999 along the east coast of the United States, the news media has provided extensive coverage of other outbreaks. Mosquitoes, which usually contract the virus by feeding on infected birds – then bite a human and introduce the infection where it multiplies in the bloodstream. While some infected individuals will remain asymptomatic, most will have just mild symptoms. These include
fever, headache, nausea and vomiting, body aches and fatigue. In only a very small number of cases, less than 1%, will the infection develop into more severe symptoms such as meningitis, convulsions, paralysis and mental confusion.
Though there are no medications that can treat the West Nile virus infection, the symptoms typically resolve in a few days. As noted, the vast majority of case will have mild symptoms that require supportive care such as ibuprofen for fever and body aches, and old fashioned rest and fluids. In the more severe cases – patients may need to be admitted to the hospital for higher levels of support and monitoring.
The most important consideration for families is to take measures to prevent exposure. Mosquitoes prefer to gather and lay their eggs in areas of standing water such as stagnant ponds, bird bathes and flowering pots. People should avoid these types of areas, and even consider removing them from their yards. Mosquitoes prefer to feed at dawn and in the early evening, so remaining indoors during these times is advisable. When outside, it is critical to apply insect repellent with DEET as noted in the discussion of Lyme disease.
The virus can not be spread from person to person – so infected individuals need not be quarantined.
During the coming months families need to be aware of Lyme disease and West Nile virus. Should anyone have a potential exposure, or develop symptoms of either infection – they should contact their primary care physician immediately.