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In today’s crazy world of STI’s, mutant super-germs and encroaching pandemics, it’s nice to know that certain diseases are still spread by the time-honored and evolutionarily viable method of zoonotic transmission. Unfortunately, despite the fact that arthropod-vectored diseases are alive and well, many people seem unprepared to deal with the creeping menace at its source; the many-legged crisis lurking all around our world. In an effort to familiarize you with these pestilent pests, I would like to introduce you to a common cause for concern. I’m pleased to present to you, the E2 community...

The Lonestar Tick

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Subclass: Acari
Order: Ixodida
Family: Ixodidae
Genus: Amblyomma
Species: Amblyomma americanum

Can't lose my name, it's on all my stationery!


Distribution:

The Lonestar tick is a common acarid found in the Southeastern United States. It has increased its range in recent times as far west as Texas, upwards toward Iowa, and all along the East Coast. The tick has moved up far enough to acquire real estate in Long Island and possibly Maine, probably through incidental introduction by some unwitting abettor. The amount of movement of people around the country and the purported changing climate in this hemisphere will probably encourage the tick to spread to new parts of the United States in coming years. I am unaware of any Lonestar tick populations in other countries, but I would imagine that it could be introduced and supported in other suitable environments in much the way it can be moved throughout the U.S.

Like many tick species, the little buggers enjoy living in wooded and shrubby areas, possibly along a water source. This probably allows them greater access to larger animals that are entering the area to drink. The trees and brush provide cover until an appropriate host wanders by.


Description:

The Lonestar tick female is brown, roughly 0.33 inches (almost a centimeter) long when fully grown, and easily recognizable by the large round yellowish or whitish spot on her scutum. This “shield” is what marks her as a hard tick and will not change in shape or size, even when the tick has fed and has engorged herself to roughly the size of a TLC drama-mentary subject. That is to say, she will grow to roughly 0.5 inches in length (her girth is anyone’s guess, but I’ll tell you they look like horrific little putrescent grapes with legs) when she is fully fed. This retention of the shield is highly useful for determination of species when and if a tick is discovered on a person. Of course, one should always retain any ticks one finds on oneself, as it’s better to leave identification up to the experts. It will also help in culturing certain free-loaders in the tick, but we’ll get to that in a minute.

Male ticks are more difficult to identify because they lack the lone star on the back. They too are brown, but with somewhat random patterns of spots and stripes around the margin of the body. They are slightly smaller than the females, and will not become nearly as large when feeding. Mama has to put on a lot of baby weight, after all.


Development:

Speaking of mommy ticks, it is important to know how and when that miraculous act occurs for ticks. Lonestar ticks become active sometime around March, when temperatures begin to rise to the 50° F. Thus, the relative peak of activity for ticks in an area may be offset by several weeks to a month in environments that are colder or experience more prolonged winters than the South endures. Adults search for hosts in their arboreal ambush sites by using sensors on their legs that seek heat, vibration, and carbon dioxide emission— all tell tale signs that a host is coming. Adult ticks will feed on pretty much any mammal large enough to support their voracious appetite. It has been noted that populations seem to establish themselves in places where there are large supplies of prey in the form of cattle or deer. Unfortunately, they often also choose to attach themselves to humans, who, while theoretically less meaty, still offer a lot of blood to the expectant couple.

Males and females mate after having taken a blood meal. The blood nourishes the male so that he can perform his duty, and provides the sustenance for the clutch of approximately 1,000+ eggs that the female will lay somewhere in the leaf litter of her home. Males may mate with more than one female if they are lucky, but will die shortly thereafter. A female really only needs one baby daddy, and dies after her eggs have been laid.

From these eggs, tiny larvae will emerge. These larvae are not quite recognizable as ticks— they are barely the size of a 12-point period ( . ) and have only six legs. However, they attach themselves to a small host such as a bird or other tiny woodland creature and take a blood meal. They then molt, entering the nymphal stage. These nymphs are much more like their parents, with eight legs and the normal set of coloration. However, they are still smaller by about half than your average sesame seed. This contributes to the common moniker “seed tick”. These little ankle-biters also search for hosts to feed on, picking something generally larger than they preferred in their younger days. After a blood meal is taken, they can enter their final molt and emerge as adults, ready to bleed and breed all over again. The entire life cycle may occur in only a few short months, with a tick hatching, molting, and reproducing during one short early spring to early fall cycle. However, if conditions don’t favor this rapid boom in growth, ticks may live for up to three years before they finish their life’s work.

All life cycle stages of the tick require a blood meal in order to move on to the next round. Because they generally feed on different types of hosts during each stage of growth, the Lonestar tick is referred to as a “three-host” tick. However, all stages of tick can feed on humans.


Disease:

The bite of a tick, due to multiple factors involved in the bite process, is known to cause redness, swelling, irritation and discomfort. When a bite is administered too closely to the spinal column, feeding and inflammation may even result in a sometimes life-threatening condition known as tick paralysis. However, the little wretch is also known to play host to several other more serious diseases caused by a variety of disease agents. Lonestar ticks are known to vector, at the very least:

Lonestar ticks have NOT been shown to transmit Lyme disease. STARI is the disease that is often thought to be a presentation of Lyme disease because of similar clinical features, such as the appearance of a bulls-eye shaped rash. However it is NOT the same disease, as it fails to share the same disease agent. STARI is under investigation to determine the causative agent and to determine prevalence, which explains the acronym and the call from the CDC to have any cases of non-Lyme Lyme-like disease reported to them. With the possible exception of STARI, all of these diseases can affect both humans and their pets— most notably the domestic dog and cat. This means that your pets are at as much risk from ticks as you are, but it also means that if your pet is dropping or transporting ticks, the little bloodsuckers might infect the both of you. Lateral transmission through different ticks from infected person to pet or pet to person is also probably a possibility, though I couldn’t tell you the percentage at which that might happen. Of course, the diseases transmitted depend not only on the presence of ticks, but also of disease agents. If a tick population does not contain Rickettsia, for instance, it will not transmit Rocky Mountain Spotted Fever. Regrettably, nature is resilient, and one infected Rickettsial host can start the cycle of infection in an area.

Having worked in a boarding kennel and a vet clinic, I can tell you without a doubt in my mind that fleas and ticks are absolutely the worst thing I have to deal with. I have handled maggoty cats. I have had to deal with the smell of a leg rotting off the dog to which it was attached. I’ve even had to clean up an explosion of roundworms, like fetid spaghetti, before I could enjoy my lunch in the break room. But somehow, it’s ectoparasites that bring a special sort of crawl to my skin. I feel them on me even when they’re not, and it scares the hell out of me.

This is not just an unfounded neurosis; unfortunately, ticks are one of the largest vectors of disease in our world. Even more unfortunately, they are found in places that people often like to be. Hikers, joggers, picnickers, swimmers, and other nature-minded folk are at huge risk for tick bites. There are precautions to take, but they may not always work. Some people aren’t in to the whole communing thing, but may still be exposed to disease-carrying ticks that have hitched a ride on the family pet or companion animal. As stated above, this is a serious issue. Human health is of extreme import, but it is also to keep in mind that allowing tick infestation to occur on pets can also result in life-threatening diseases for them.

Prevention methods such as pesticide application and appropriate dress will discourage bites and subsequent disease. Any and all ticks collected from a person who has been bitten should be saved, preferably in a little jar of alcohol, for several weeks. In the event of disease symptoms surfacing, having the monster that bit you may be able to clear up some questions about your potential fate. This same protocol should probably also be followed for pets, though it may be a little more difficult, as pets tend to accumulate many more ticks than humans and it may be difficult to keep up. Also, it may turn your pantry or garage into some sort of sick aquatic tick circus and scare the neighbors and family friends, but certain sacrifices are sometimes required in the name of public health.


Denouement:

There you have it. The Lonestar tick is readily identifiable due to her characteristic markings. Males are less flashy, but are found in close proximity to the fairer sex. As ticks grow and flourish in their woody escapes during the late spring and throughout the summer, they harbor the potential to wreak havoc on the lives of people and animals that wander unwitting in to their midst. I hope that this has been a satisfactory introduction to one of the less necessary evils in the ecosystem, and until next time, I hope you stay safe and parasite-free.


Doggerel:

This is my own personal experience from the clinic— not necessarily with the Lonestar tick, but with tick-borne illness in general.

A family owning six dogs brought three in to us complaining of illness. When we inspected them, it became readily apparent that they were suffering from a tick-borne illness. There weren’t 2 square inches on the animals that did not have a tick. They turned up positive for Ehrlichiosis and Rocky Mountain Spotted Fever. It was frightening for the dogs because some of them were fighting two potentially devastating infections at the same time. It was frightening to me because the dogs lived on Fort Gordon, meaning there were soldiers performing field exercises in this disease-ridden environment. And it was frightening for the hospital because the dogs were dropping ticks left and right, which could easily attach themselves to other patients or clients, and to us.

I don’t know if the ticks were Lonestars or not because I never looked at them very closely. I did, however, swear loud and long in front of a group of small children when a fully-fed female tick detached herself and rolled off the “healthy” dog we’d been curing for the past three weeks and landed on the floor. I wouldn’t have sworn, but I nearly stepped on the thing. When I realized exactly what the soft squishiness beneath my foot was, I just couldn’t help it. Had I popped her, the blood meal she had taken would probably have aerosolized and there’s a good chance I and the kids could have inhaled some sort of bug we really didn’t need to have.

You have to love medicine.


Data:
http://www.merckvetmanual.com
http://entomology.ucdavis.edu/faculty/rbkimsey/tickbio.html
http://www.entomology.cornell.edu/MedEnt/TickBioFS/TickBioFS.html#N100E1
http://www.cdc.gov/ncidod/dvbid/stari/stari_LoneStarConcern.html
http://insects.tamu.edu/fieldguide/cimg370.html
http://www.tickinfo.com/lonestartick.htm
http://www.co.monmouth.nj.us/mosquito/startick.html
http://www.stopticks.org/ticks/ticklonestar.asp
http://www.ipm.iastate.edu/ipm/iiin/tlonesta.html

Diagrams: http://bugguide.net/node/view/21258/bgimage