| Tick-Borne Diseases |
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This month, Michael Waldvogel, PhD of NC State University sent out some pest information about common pest problems in and around homes at this time of year. Most of you have probably heard that the CDC recently confirmed that the death of six year old Buncombe county child was due to Rocky Mountain Spotted Fever (RMSF).
When most people think of ticks and tick-borne diseases, they focus their attention on Lyme Disease which is more prevalent in the northern states but certainly is on the rise in North Carolina and can have severely debilitating effects if it is not diagnosed promptly. In 2012, we had 584 cases of the Rocky Mountain Spotted fever with the peak occurring in June and July. The American dog tick is the primary vector (transmitter) of RMSF. The blacklegged tick is the primary vector of Lyme Disease in North Carolina.
Many people may be inclined to try outdoor chemical treatments and that’s certainly their option (if the weather cooperates). They need to bear in mind that tick management requires a thorough (NOT excessive) application of the chemical. Unlike with mosquitoes where the goal is to treat foliage where the mosquitoes are resting, ticks are often down on the soil itself and so the chemical application needs to cover the soil. With that in mind, your best options are going to be a garden hose sprayer attachment or a granular insecticide. Both need to be done when the grass is not excessively wet (the granules can get caught in the wet grass and not reach the soil surface where they’re needed). Point #2 to keep in mind - you may “control” the tick population in the treated areas of your yard, but this does nothing to address the ticks in the weedy overgrown areas that remain untreated and may be home to rabbits, feral cats (not likely both at the same time), etc.
This is a good time to reiterate the good practices for protecting yourself from ticks and *all* of the tick-related diseases.
- Whether you’re outdoors for work or recreation, keeping ticks off of you is important. One way is to wear light-colored clothing to make it easier to spot ticks making the ascent up your leg and preferably wear long pants and tuck the pant legs into your socks. Whether you wear shorts or long pants, apply a repellent to your socks and pants or in the case of shorts, only to *exposed* parts of your skin.
- Check yourself (and children) over carefully after working or playing outdoors.
- If you do find a tick that’s feeding on you, remove it carefully with a pair of tweezers. If possible, keep the tick for identification (suggest that they keep it in a small jar filled with rubbing alcohol.
- Just because you find a tick on you, doesn’t mean it’s been feeding, particularly if it’s still wandering around. Ticks attach their heads to your skin with a type of “cement” and then the feast begins.
- Also, just because the tick is identified as American dog tick or the blacklegged tick does not mean that is actually infected with Rocky Mountain Spotted Fever or Lyme Disease. People may rush to their doctor to get a blood test done. However, at this early stage a blood test isn’t helpful because the tests rely on detecting antibodies that develop in response to the pathogen and it can take several weeks for the antibody levels to reach detectable numbers. Also, some healthy people who have been exposed to RMSF may already have detectable levels. For that reason, blood tests are usually done twice a few weeks apart to look for a significant rise in antibody levels (indicating a likely infection rather than just a previous exposure).
Remind people that 20% or more of the people infected with the Lyme Disease pathogen do not develop the classic “bull’s eye” rash that they just saw after doing a Google search. The CDC also reports that 10% of people infected with Rocky Mountain Spotted Fever do not develop the characteristic rash that we read about (and of course, rashes on children or adults can have many other non-disease causes). The best approach is to circle the date of the “tick encounter” on the calendar and if you develop flu-like symptoms, severe headaches or joint pain within the next 3-14 days, contact your physician immediately and mention the tick incident. Most doctors will take the cautious route and prescribe antibiotics which when taken early on usually take care of the problem.
Spotted Fever is one of those illness that are a piece of cake to treat and cure IN THE FIRST TWO OR THREE DAYS OF ILLNESS, but which can be a nightmare if treated later. If given early, the antibiotic treatment is virtually 100% effective, and quickly so, with close to zero adverse effects. But if delayed much beyond that, disability or death are fairly common, despite all treatment. So everything hinges on early recognition and treatment.
So how to recognize it? You are right in observing that there are no blood tests, or any other medical procedures, that can help diagnose it in the critical early stage. Everything hinges on the doctor suspecting it. And anything the patient can do to help him think of it.
When you say Rocky Mountain Spotted Fever, everyone thinks of a fever and a rash. But the rash often comes too late --- only after three or four days. And sometimes doesn’t even happen. So the key is when to suspect that a fever, out of nowhere, may represent spotted fever.
The knowledge that a tick fed on you a week or two before is of course a big clue. (We think it has to be imbedded for at least several hours to transmit the disease.) But there are times when a tick can attach itself, feed for a while, then detach, without your knowing it. So you can’t count on that.
The critical symptoms are fever (usually pretty high), headache, and terrific muscle aches. Especially the muscle aches. Of course all sorts of illnesses --- flu, etc --- can start off with fever and achy muscles. But the muscle aches of spotted fever are something else! If a patient comes to an experienced NC doctor’s office during tick season (late spring to early fall), with no symptoms except a sudden fever and severe pain in his muscles, --- even with no knowledge of any ticks biting him, and no rash --- the doctor will usually let fly with doxycycline treatment without further ado. This is one of those illnesses where early treatment is so safe and effective, and delayed treatment so potentially devastating, that doctors reverse their usual routine of diagnosing first and treating second. Here we will treat even on suspicion.
So in the summertime, the sudden onset of fever and severe muscle aches is a reason for a doctor visit, THAT DAY! Even if you have seen no ticks, nor any rash. The fever will be high enough, and the muscle pains severe enough, that you won’t likely dismiss it as “a little virus that’s going around.” You will suspect something more severe is afoot. And if the doctor does not consider spotted fever, bring it up with him.
Two other caveats come to mind: 1. If you find a tick on you, but aren’t sick, don’t go to the doctor with that. Remember you have to have a sick tick (one carrying spotted fever) to make you sick. And 99 out of 100 ticks probably aren’t carrying it. So we would not prescribe the antibiotics just because the tick was on you. Just watch for the fever and muscle pain over the next two weeks.
2. Don’t take some left-over antibiotics that you were supposed to have taken last year for some other illness. Rocky Mountain Spotted Fever requires a very specific antibiotic --- one not often prescribed for other illnesses.
by Michael Waldvogel, PhD, NC State University
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