Summer is almost approaching, and with it comes the heat and humidity that promotes the development, breeding, and spread of ticks and fleas, which are persistent pests. This summer is already shaping up to be a banner year for these pests, thanks to unusually heavy rains. Both of these can contain several diseases that cause tremendous discomfort to humans and may even be fatal to some pets, in addition to being a source of great irritation.
Ticks
Ticks are little arachnid parasites that feed on the blood of both animals and people. There are seventy tick species in Australia, 14 of which are soft ticks (family: Argasidae) and 56 of which are hard ticks (family: Ixodidae). Only 16 of the 70 species will eat humans and domestic animals, while the remaining 54 will eat only wild mammals, reptiles, and birds.
The paralysis tick, Ixodes holocyclus, is the most common in Australia. This species is responsible for almost 95% of tick bites in Eastern Australia and most tick-borne illnesses. The paralysis tick is exclusively found on Australia’s east coast. It is absent from Western Australia, the Northern Territory, and South Australia. Bushwick, Haemaphysalis longicornis, Brown Dog Ticks, Rhipicephalus sanguineus, Cattle Ticks, Boophilus microplus, is prevalent species.
The egg, larval (about 1mm in length and light brown when not full of blood), nymph (approximately 2mm and pale brown), and adults (4–5mm in length when not engorged and up to 1cm if full) are the four stages of a tick’s life cycle. To develop from larvae to a nymph to an adult, the Paralysis Tick has to feed on blood. The mature female takes blood to gain protein for egg-laying. While feeding, female paralysis ticks can transmit a poison to their host, which can cause illness, disease, and even paralysis or death in pets, especially dogs.
Ticks are especially dangerous to pets because they are more likely to enter tick-infested areas.
Females slip off their hosts after feeding and mating, deposit eggs, and eventually die. A single female can produce thousands of eggs. Eggs are frequently placed in leaf litter, soil, and dense foliage places like long grass or bushy shrubs.
Depending on temperature and humidity, the egg hatches into a six-legged larva or seed-tick after one week and up to 90 days. Seed ticks grow into 8-legged nymphs after feeding and molting. Nymphs resemble adults in appearance, although they are smaller and sexually immature. Nymphs mature into sexually mature adults after feeding and molting.
Some ticks, such as Bush and Paralysis Ticks (3-host ticks), require many hosts to progress to the next stage of development, but others, such as Cattle Ticks, require one host.
The juvenile stage of the tick’s life is spent away from the host for most of its existence. Ticks can be found in damp, cold regions when they are not attached to a host, as ticks are prone to drying up in hot, dry environments.
The paralysis tick thrives in moist, humid coastal environments with plenty of native animals to feed on. Long grasses and bushes are great habitats for paralysis ticks, and if you live near these regions, you may find them in your garden. The larval stage of this tick is most active throughout the autumn months, the nymph stage during the winter, and the adult stage during the spring. During high humidity, especially after rain, this tick is most active.
Paralysis Ticks aren’t very mobile, so they rely on passing animals for blood. The paralysis tick will climb grass stems or branches to ‘perch,’ ready to latch on to a passing mammal, including humans. In their natural habitat, they rarely grow higher than 50cm. They can walk up the body and connect to the head area once they’ve found a host.
Tick control is part of an integrated pest management strategy.
The primary approach of tick control is to minimize the tick-friendly environment: Keep lawn sections neatly mowed; weeds to a minimum; eradicate weeds and try to establish a buffer strip if near to bush areas; prune and thin out plants to prevent humidity.
Pesticide sprays will kill adult ticks when they are elevated looking for a host. Regular pyrethrum-based insecticides are effective. However, residual or systemic insecticides offer no practical benefit. Because they live in dense foliage or leaf litter, the larval or nymph stage is difficult to control.
Fleas
In Australia, there are three major flea species.
The most prevalent flea in Australia is the cat flea, Ctenocephalides felis. It preys on dogs, rodents, people, and other mammalian species.
Ctenocephalides canis a dog flea that is less frequent than the cat flea but looks similar.
Pulex irritans, the human flea, have become rare as home cleanliness standards have improved.
Fleas are parasitic insects that feed on blood. They are members of the Siphonaptera order of insects, which means ‘wingless siphon.’ Their most notable characteristics are the irritation produced by their bite, and the horror felt when they are spotted on household pets.
Females feed their eggs with blood and lay up to four eggs per feed. Throughout their several-month life cycle, a flea will typically lay 100 eggs. The eggs are oval, tiny (approximately 0.5mm), and pale in color. Depending on environmental circumstances, they can hatch in as little as one week, or they might remain dormant for months in unfavorable conditions. The larvae that hatch from the eggs have the appearance of small white larvae, measuring around 3 mm in length and covered sparsely with extremely fine hairs. These squirm around looking for food, typically skin scales or undigested blood secreted by adults. They will seek shelter in cracks and crevices and are rarely observed.
Larvae go through four molts (instars). Warmer temperatures hasten the life cycle. By creating a cocoon, the final instar will create a pupa. Depending on environmental conditions, they will survive metamorphosis into adult fleas inside this cocoon for one week to many months. Only when they sense movement and vibrations from a potential host will they emerge from the cocoon.
Flea control, like tick control, is an integrated pest management effort.
Hygiene and housekeeping procedures, regular, thorough vacuuming of the home, and cleaning and treating dogs and their bedding are all primary physical management. Fleas on animals can be treated with a variety of licensed remedies.
Flea-infested areas, such as carpets, should be treated with a registered residual pesticide, ideally, one that contains an IGR, that should also be administered to any harbourages where flea larvae may be present. Sandy regions around dwellings and the subfloor area are popular flea breeding grounds that must be treated with the pesticide. Because many sandy soils are water-resistive, adding a soil wetting chemical will considerably boost the pesticide treatment’s efficacy.
