Ticks - Those little blood suckers

 Those who visit the bush regularly or live in close proximity to the bush occasionally have to deal with these little blood suckers; and the more you know about them, the easier it is.

Life Cycle                                                

Tick eggs are laid in moist leaf litter or under bark and incubate for around two months before they hatch into six legged larvae (sometimes called seed ticks because they look like tiny seeds). Once hatched, they climb vegetation and wait to hitch a ride with their first host which is usually a native mammal. They insert their mouth parts into the skin and suck blood for about 4-6 days, after which the engorged larva drops to the ground and moults into the eight legged nymph stage.

Once again, the ticks climb vegetation and wait for a host to brush past and provide them with their next meal. Four to seven days later, they once again drop to the ground and undergo the second moult which produces the adult.

For a third and final time the ticks wait for passing hosts from the leaves of shrubs, trees and grasses. Adult ticks can suck blood from practically any animal and will remain attached for up to around 20 days.

Male ticks will wander around on hosts in search of females to mate with but do not suck blood from hosts; instead, they just die once they have mated. Female ticks, after mating and feeding, drop to the ground again and after about 3 weeks lay around 2500-3000 eggs and die.

How can ticks be dangerous?

Ticks present a danger on two fronts: Firstly, they are poisonous. Ticks need to dilute and partially digest their blood meal before they can suck it up, so they ‘spit' their saliva (which is toxic) into the bite site and then suck it back up with a little blood. They repeat this over the course of their meal and during this time, some of the toxin escapes into the host. Because the adult female can remain attached for up to three weeks, the amount of toxin can build up to dangerous levels. Under these circumstances, some tick species can cause paralysis in humans and even death.

Secondly, because ticks require three different animal hosts during their life cycle, their mouth parts can easily transfer disease from one host to another. Diseases attributed to tick bites include tick typhus, Q fever and Lyme disease; all of which are caused by bacteria.

Control

To avoid tick when you are out in the bush, sensible clothing is the go. A broad brimmed hat, a tucked in long-sleeved shirt and long pants tucked into socks or boots can prevent ticks gaining skin contact and light colours make them easier to see.

You can also avoid brushing through places where ticks hang out such as long grass, shrubs and narrow tracks that animals use.

Ticks are well adapted parasites; they have a very light touch and you usually won't notice them on you even after they've buried their heads under your skin and are busily feeding on you. Because of this, it is important to have a good look for them when you return home from the bush.

Throw your clothes straight into the washing machine (wash them in hot water: ticks can survive a cold wash) and have a thorough body check, especially the groin, armpits, back of the neck and under the hair (use a mirror for hard to see places), have a hot shower and check again. If you live near a bush site you should check yourself, your kids and your pets every day or so between mid spring and early autumn.

Tick Removal

One recommended method of tick removal involves smothering it in Vaseline, or better still, gel toothpaste.. It works on the idea that the tick will begin to suffocate and decide to pull up stumps and move on. This method does work but the tick will take its time pulling out (sometimes up to 45 minutes) so be patient.

If, for some reason this doesn't work, or if you can't stand the idea of having a tick attached to you for one more minute, it can be removed with tweezers. Holding the open tweezers parallel to the surface of the skin on either side of the tick, push them firmly into the skin and close them around the tick's head as close to the skin's surface as possible; then pull it steadily out. Curved tipped tweezers work well for this.
Drop the tick into methylated spirits or soapy water to kill it, disinfect the bite site and wash your hands with soap and water.

The only drawback to direct physical removal is that ticks readily leave their mouthparts behind. This shouldn't pose too much of a problem (the head does not continue to pump in poison) and is no worse than a splinter as long as the bite site is thoroughly disinfected.

A combination of these two removal methods works well: the smothering makes the tick let go so that the physical removal with tweezers is easier and the mouthparts aren't left behind.

If you have an infestation of larval stage, seed ticks, a half hour hot bath with one cup of bicarbonate of soda should do the trick.

Do not:

• Squash the attached tick or try to remove it with your fingers; the poison glands are located in the tick's body so squeezing it will only inject more poison into you.
• Put methylated spirits or any other toxic chemical on the tick; it will only irritate it and cause it to spit out more poison.
• Touch the tick; it may be carrying some nasty bacteria.

 If the above advice is kept in mind, with a little vigilance the bush experience can be enjoyed throughout the spring and summer months without too much trouble from these little blood suckers!

References

Dole Klein, H. & Wenner, A. M. 1991, ‘Tiny game hunting: environmentally healthy ways to trap and rid pests from your house and garden', Transworld Publishers, Moorebank, NSW.

Ticks 2002. Retrieved September 19, 2006, from http://www.health.nsw.gov.au

Underhill, D. 1996, ‘Australia's dangerous creatures', Readers Digest Australia, Surrey Hills, NSW.

Microphotographs by Peter Fallon, Murdoch Uni WA.