Ticks Lyme Disease
We’ve made the point in several of our BugInfo articles that arthropods, and insects in particular, can have a tremendous impact on the health and happiness of humans. One of the most important areas they affect us is with respect to their ability to “vector” many kinds of diseases, and of course the champions in this area are still the mosquitoes.
However, many other kinds of arthropods also pass lethal or debilitating diseases to people, and one of these that has long been known to be an important vector is the Tick, or rather the Ticks, for there are dozens of different kinds of ticks in North America, and many of the species are implicated in disease transmission. Ticks may be one of the most efficient vectors of disease, in fact, for they are capable of spreading a wide variety of pathogens – bacteria, viruses, rickettsiae, and protozoans – as well as causing a paralysis due to toxins in their saliva.
For many decades an ailment in people that caused various symptoms, including severe pain in the leg joints and strange bruises on the skin, was not well understood. It was diagnosed as different possible conditions, including rheumatoid arthritis. Then, in the 1970’s in several small towns in Connecticut named Lyme, Old Lyme, and East Chatham, an excessively high outbreak of the problem was occurring, and the Connecticut State Department of Health began to investigate. They soon realized that this was something other than rheumatoid arthritis, and by 1975 it was established that it was a disease caused by a bacteria called a spirochaete, and the link to ticks feeding on people was made. In honor of the town where much of this research was done this now-identified disease was called “Lyme Disease”.
Since that time a great deal of new information has been discovered, including a second, similar disease called Ehrlichiosis, also spread by ticks. We now know that there are at least two different bacteria responsible for causing Lyme Disease, and at least three species of ticks that can spread it. In the eastern United States the prime culprit is the Deer Tick – Ixodes scapularis – in the western U.S. it is the Western Black-legged Tick – Ixodes pacificus – and a third tick common in the south and southeast is the Lone Star Tick – Amblyoma americanum. The two species of Ixodes are considered to be the primary vectors of this disease, and they are fairly distinctive ticks. As adults they are smaller than many other ticks, they are a dark reddish-brown color, and they have extremely long mouthparts sticking well out in front of their head.
Ticks grow from the egg to the adult by what is called simple metamorphosis, meaning their appearance does not change much. They emerge from the egg as a tiny tick, shed their skin some months later to become the second stage and a slightly larger tick, and then shed their outer skin one last time to become the adult tick, at which time males and females mate and large numbers of new eggs are laid. The life cycle of ticks, from egg to adult, generally takes around 2 years.
The good news, if there is any, is that the bacteria that causes Lyme Disease does not appear to enter the eggs of the tick before being laid. Therefore, the first stage ticks are not infected, as those that spread other tick-borne diseases may be. This, at least, slightly lessens the chances of being infected. The first stage ticks become infected by ingesting the blood of an infected animal, and a curious situation has been seen here that still is not well understood. In many parts of the eastern U.S. the percentage of infected ticks is very, very high – perhaps two out of three ticks are carrying Lyme Disease bacteria. However, in most of the western U.S. the percentage of infected ticks is only around one or two percent. The obvious implication with these numbers is that those who live in tick-prone areas of the eastern states are far more likely to be fed upon by an infected tick than those in the West, and thus the difference in Lyme Disease incidence between the two geographic areas.
A possible explanation for this difference in the infection rates in the ticks has to do with their choices of meals. The early stages of ticks feed primarily on small animals, particularly the White Footed Deer Mice, but in the West they also feed quite commonly on the Western Fence Lizard – also referred to as “blue belly lizards” due to the shiny blue stripes on each side of their tummies. It appears that some chemistry in the blood of these lizards kills the bacteria, and thus ends the cycle of that pathogen at that point. More to come, no doubt.
As the ticks move to the adult stage their choice for meals becomes the larger deer, dogs, or other animals, and if the ticks fed on an infected animal in their previous two life stages they will be infected as adults, and pass the bacteria into the blood of this large animal, causing it to be a carrier as well. Dogs are susceptible to Lyme Disease, and a vaccine has recently become available to prevent it in these animals. A vaccine for humans is apparently close as well, but studies are still in their early stages as of 2002, and the effectiveness in preventing human Lyme Disease is not yet known.
What are the symptoms of Lyme Disease?
Unfortunately, the symptoms of this disease are fairly erratic, in that not everyone experiences the same thing at the same time. We can speak in terms of what appear to be the “normal” symptoms though.
- Stage One – from 3 days to a month after being bitten by an infected tick you feel very much like you have the flu – fever, chills, fatigue. This often is accompanied by a rash called a “bulls-eye” rash, due to its appearance as an expanding ring. The rash may not even be at the site of the bite, and later it may expand to several spots in other areas of the body.
- Stage Two – may occur months later as more rashes along with dizziness, fatigue, severe pain in the joints, and shortness of breath. Another more terrible effect is possible paralysis of muscles in the face, leading to a condition called Bell’s Palsy, due to damage to the nervous system. Stage Two may occur on and off for a long time, with periods where you feel much better, only to have the symptoms reoccur.
- Stage Three – in a small percentage of cases the heart becomes affected and weakened, leading to more severe problems. Also, the pain and swelling of the joints becomes even more pronounced over time, leading to chronic problems there as well.
Lyme Disease is not to be confused with Tick Paralysis though. Tick Paralysis is caused by a toxin within the saliva of the feeding tick, and usually within a week after a tick has begun feeding you would feel numbing and weakness of the legs and arms, along with muscle pain. This could lead to difficulty in swallowing and facial paralysis, or possibly to worse complications if left untreated.
Guidelines for preventing Lyme Disease
The key word here, without a doubt, is “PREVENTION”. There are many steps you can take to prevent a tick from biting you in the first place. Another small piece of good news, with respect to Lyme Disease, is that an infected tick does not pass the bacteria into the animal it is feeding on for at least the first 12 hours it is embedded, and in many cases not for at least 24 hours. For you this means that you have a little grace period to inspect yourself and remove any ticks you may find, even if they already have begun to feed on you.
Thus, Step One is to recognize what a tick looks like. In general they are small – usually only about 1/8″ to 3/16″ long before feeding, although as the female feeds she expands to enormous proportions. In some of the wood ticks the female may end up the size of the fingernail on your pinkie finger, filled with the blood she uses to nourish the huge crop of eggs she will lay. They are flat, they have no wings, and they have eight legs as the adult tick (strangely, the first stage of the tick has only 6 legs). Ticks cannot jump, and they move very slowly and deliberately as they crawl, often with the instinct to crawl in an upward direction.
Step Two is to avoid contact with vegetation if possible, including tall grass. The second and third stages of ticks commonly climb up onto vegetation to enhance their chances of latching onto a passing animal. This is referred to as “questing”, and the tick will detect movement, body heat, or carbon dioxide from a nearby animal, at which point it raises its front legs to quickly grab onto anything that brushes against the plants. If you live in a somewhat rural area you should keep the grassy areas around your home mowed on a regular basis.
Step Three is to remove ticks from you or your clothing quickly and correctly. If you are walking or involved in activities in areas where ticks are likely to occur you should stop every few minutes and inspect your legs or pants. If ticks are likely to be common there you should wear long pants of a light color, with the pants tucked into your socks. This allows you to see the ticks more easily and prevent them from crawling under the pants onto your legs, where they are now hidden. Similarly you should tuck your shirt into your pants to keep the ticks on the outside for as long as possible, and have a companion check your backside where you cannot easily look.
If you find ticks on you they can be picked off with your fingers and discarded. Should you want to take the time to kill the tick, though, be prepared for a tough time. Ticks are like little pieces of leather, and simply mashing it with your fingers just won’t do the trick. You will need to cut it with a sharp object, a pointed stick, or a rock in order to kill it.
Step Four – in case the tick has already embedded itself in your skin, the process takes a little more time. My first major caution is to ignore the many ways you may have heard for removing a feeding tick. Here is a short list of methods I have heard:
- Twist it out counter-clockwise, since they spun themselves in clockwise. (False!)
- Set fire to it (Bad idea).
- Put a cigarette near it and the heat will make it back out (also a bad idea, and I have to suggest that cigarettes aren’t good for you either).
- Coat it with Vaseline and once it starts to suffocate it will back out (another in the long list of bad ideas).
- Put rubbing alcohol on it and it will back out or be killed (our final bad idea).
The reason so many of these methods are a “bad idea” is that you truly do not want to irritate the tick if you can avoid it. You are trying to avoid being inoculated with whatever disease-causing pathogens are in the tick, and if you cause it distress there is a chance the tick will simply vomit its stomach contents or saliva into you. The suggestion from health authorities and researchers on ticks, for safely removing the tick after it has begun to feed, is to take a sharp-pointed tweezers that can get right down to the head of the tick at the skin, and sllooowwwwly pull it away from the skin. As you exert this slow pressure the tick will finally give it up, let go, and be removed intact. Any quick pull may break off its head, leaving you with a chance for infection.
Once the tick is removed you should thoroughly cleanse the area with a disinfectant, and then just keep an eye on it for a few days to ensure any swelling or redness are going away. Since they like to crawl “up”, some common places they choose as feeding sites are at the hairline at the back of the head or behind the ears, as well as at the lower back. Pets should also be checked daily if they are active in tick areas, and if your dog has long hair your inspection will need to be very thorough, pulling the hair back and checking down to the skin. Ticks commonly end up around the ears and neck on dogs.
You can also use a commercial tick repellent on your pant legs and on your pets to help discourage them from staying on. On pets there are also excellent dusts or sprays to kill ticks that may be hidden in the hair. Dogs, horses, cows, and other domesticated animals are susceptible to Lyme Disease, and may also develop some of the same symptoms as humans.
Lyme Disease is a worldwide problem, being found in North America, Europe, Australia, and many countries in Asia. It can have horrible complications for those who are infected with it, but some simple steps will help you to avoid the ticks and still enjoy the great outdoors. Should you be bitten by a tick you can remove it in the correct manner, save the tick for identification later in case you start to feel symptoms consistent with the tick-borne diseases, and consult you doctor if illness develops. Antibiotics are very effective in curing Lyme Disease if it is caught in its earliest stages
Source: BugBattalion California