July-September, 2003

Ask Dr. Clark

Lyme disease resolves promptly if treated early

Warming up to our Midwestern weather? You’re not alone. Ticks and mosquitoes in our part of the country are doing much the same, but these insects have the potential to inflict suffering on humans.

The Department of Health reports that it has received increased reports of tick-borne diseases in Missouri and Arkansas over the last several years. These illnesses include Lyme disease, ehrlichiosis, tularemia and Rocky Mountain spotted fever.

Anyone who has been bitten by a tick and suffers from a local rash, general rash, fever, headache, achy muscles, nausea, vomiting or malaise should contact their physician for evaluation.  In other words, anyone who thinks he or she has the “flu” in the non-flu season (especially after a possible tick bite) should be considered as having one of these conditions spread by ticks.

Let’s look at Lyme disease in particular. Bacteria cause Lyme disease and the bacteria are spread by the bite of a tick. The reservoir for the disease is actually in rodents. Ticks acquire the infection by biting rodents, then pass it on to humans.

Fortunately Lyme disease does respond to antibiotics, the problem is it is sometimes difficult to diagnose. In 1975 when Lyme arthritis was recognized, it soon became clear that this was not a disorder just of the joints and skin.

Lyme disease has been reported in 48 states as well as across Europe and Asia. Annual cases in the United States alone number more than 10,000. The disease usually manifests between May and November with the peak being in June or July. The primary vector or transmitter of this disease is a tiny ioxidid tick. It would seem easy that if once bitten by a tick and a rash develops, a patient might seek medical care.                       However, in one study only 31 percent of patients who had the disease actually recalled a tick bite. This is probably because many of these ticks (seed ticks) are much too small to notice without careful inspection.

After a tick has engaged the skin for about 24 hours there is a chance that if the tick is carrying the bacteria that causes Lyme disease, it will spread into the skin. Within three to 32 days the bacteria migrate outward into the skin and this causes the rash, which is described as red and circular and has distinct characteristics. This rash and initial infection is otherwise known as stage I Lyme disease. This may be followed weeks to months, if left untreated, by other diseased organ systems (heart and nervous system).  It is only much later that the arthritis appears in stage III disease.

If one develops a rash after a tick bite, the health profession recognizes this classic rash in about 90 percent of patients. The outer border of the rash is generally red, flat and without any scaling.

The rash is not the only symptom of the stage I disease. There are also flu-like symptoms: fatigue, headache, fever and chills. One may even develop joint and muscle aches. This is why if someone develops a flu-like illness in the summertime when the flu virus is not present in the general population, the clinician must think of Lyme disease as being the culprit.

Fortunately, if treated early with oral antibiotics, Lyme disease and the rash resolve promptly. The course of antibiotics will generally last about 21 days.

Prevention tips when entering wooded areas

• Wear long sleeved shirts, boots (or shoes with socks) and long pants. Keep your pants tucked into the footwear.

• An insect repellent with DEET on exposed areas is advised.

• Do a full body inspection for ticks after arriving home.

 
Tips for removing ticks

•  Remove ticks as soon as possible (it takes about 24 hours of tick-skin exposure to spread the disease).

•  If the tick is deep in the skin, try this technique: Cover the tick with petroleum jelly to suffocate it. Wait 30 minutes, then try to grasp the tick with fine tweezers, grasping as close to the skin as possible. If you pull the tick too roughly, tick saliva may be forced into the skin. Gently pull the tick away from the skin and be sure all the parts of the tick are removed.

• Clean the bite area with soap and water and apply antibiotic ointment about two to three times a day.

• Watch for any signs of rash over the next one to two weeks.

 
West Nile virus update

The West Nile virus now appears to be firmly entrenched in the U.S., and scientists expect the virus to continue to spread into wildlife populations.  As of this writing, only Hawaii, Alaska, Nevada, Ohio, Utah, Nevada and Arizona have not reported any index cases. Statistically, a person's risk of contracting West Nile is low. In most areas where the virus is established, only 1 percent of the area's mosquitoes carry the virus. Moreover, only 1 percent (or less)  of people bitten by these infected mosquitoes develop serious complications.  The vast majority only manifest flu-like symptoms, or no symptoms at all.

Those at highest risk are the elderly and people with weakened immune systems; it is important, however, for all people to protect themselves from mosquito bites to minimize the risk of infection.  

Tips for avoiding mosquito bites

• Apply insect repellent containing DEET to exposed skin whenever you are outdoors.

• When possible, wear long sleeves, long pants and socks when outdoors. Treating clothes with repellents containing permethrin or DEET will give extra protection, since mosquitoes may bite through thin clothing. Do not apply repellents containing permethrin directly to skin. Do not spray repellent containing DEET on the skin under your clothing.

• The hours from dusk to dawn are peak mosquito biting times. Consider avoiding outdoor activities during these times or take extra care to use repellent and protective clothing during evening and early morning.

• Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to breed by getting rid of items that hold water.

•Recent evidence points to individuals that have a B cell lymph deficiency to be particularly susceptible to West Nile Virus.
 

SARS news

On Feb. 26, the first case of SARS (Severe Acute Respiratory Syndrome) was diagnosed in Hanoi, Vietnam. To date, most SARS cases are in China with only a few hundred reported in North America. The mortality rate is about 3 percent in some countries. Updated information on SARS can be found at www.cdc.gov/ncidod/sars. Although the causative agent has remained elusive, it is believed to be a viral infection of the coronavirus family.

Symptoms

In general, SARS begins with a fever greater than 100.4 degrees. Other symptoms may include headache, an overall feeling of discomfort, and body aches. Some people also experience mild respiratory symptoms. After two to seven days, SARS patients may develop a dry cough and have trouble breathing.

How SARS spreads

The primary way that SARS appears to spread is by close person-to-person contact. Most cases of SARS have involved people who cared for or lived with someone with SARS, or had direct contact with infectious material (for example, respiratory secretions) from a person who has SARS. Potential ways in which SARS can be spread include touching the skin of other people or objects that are contaminated with infectious droplets and then touching your eye(s), nose, or mouth. This can happen when someone who is sick with SARS coughs or sneezes droplets onto themselves, other people, or nearby surfaces. It also is possible that SARS can be spread more broadly through the air or by other ways that are currently not known.

 Who is at risk for SARS

Cases of SARS continue to be reported mainly among people who have had direct close contact with an infected person, such as those sharing a household with a SARS patient and health-care workers who did not use infection control procedures while taking care of a SARS patient. In the United States, there is no indication of community spread at this time.

While these emerging infections are worrisome, they don’t even begin to compare with the damage done by the influenza virus during the winter, with more than 36,000 deaths last year alone. Influenza is still the most dangerous of our epidemic infections – so don’t forget your vaccination this fall.

Have a question for Dr. Clark? Alan Clark, M.D., is available to answer questions concerning general medical topics. Ask Dr. Clark is for the purpose of disseminating health-related information and is not intended for the purpose of diagnosing or prescribing. Please consult your physician before undertaking or adopting any form of medical treatment, exercise program or dietary plan.