The causative agents of ehrlichiosis, rickettsiosis, and anaplasmosis are all tick-borne bacterial infections that are readily treatable in humans, but the causative agent can be difficult to determine because the similarities among the pathogens. These include Ehrlichiosis, Rickettsiosis, Tularemia and protozoan infections. Several pathogens are known to be transmitted by the lone star tick and given the proper circumstances they may manifest into disease. Various pathogens have been shown to enter the tick by blood feeding however, most are not transmitted because the tick is not a competent vector.Īn unknown pathogen has been implicated in causing Southern Tick-Associated Rash Illness (STARI) in humans, but etiology, pathogenicity and identification are pending. The Lone Star tick is by far, the most common tick reported to bite humans in the southeastern and south-central United States. When larvae are encountered before host location, several thousand of them can be in a small area. After feeding on the host for 4 to 9 days, the larva drops off and, in 3 to 4 weeks, molts into the nymphal stage. If humidity and temperature are favorable the larvae can survive for up to six months in the environment, but typically the larval stage is shorter due to acquisition of a suitable host. Larvae, typically called “ seed ticks” due to their small size and abundance, are 0.5 to 1.0 mm long and have six legs. In laboratory settings, the life cycle can be shortened to less than 22 weeks under optimal conditions, but is usually 2 years in nature. Sizes of ticks in each stage can vary due to genetic and environmental conditions. Nymphs repeat this process however, after dislodging from this second host they molt into adults. After acquiring a host, the larva attaches, blood-feeds for 1-3 days, detaches its mouthparts, and then drops from the host to digest its blood meal and molt into a nymph. The larva then grasps the host and proceeds to move about the host, seeking a preferred feeding site. Questing is a behavior that entails climbing up an object, like a blade of grass, and waiting for a host to touch the larva. Following an incubation period, larvae hatch from eggs and progress through a quiescent (resting) period, then seek a host by questing. After dislodging from the host, the female will seek a microclimate, typically an area of high humidity at a soil level that is best suited for survival of the eggs.įemales have been shown to search for a favorable microclimate up to 61 cm from where they were experimentally placed on the ground after feeding. After feeding once in each larval, nymphal, and adult stage, the tick withdraws the mouthparts and drops to the ground to molt or oviposit.Ī tick lifecycle begins when the blood-engorged female tick falls from the host and after several days deposits ~5,000 eggs on the soil in a “protected” location, such as in mulch or leaf litter. Attachment is facilitated by the tubular hypostome and a secreted cement- or latex-like compound that attaches (“glues”) the tick to the host until feeding is complete. The ticks have piercing-sucking mouthparts with chelicerae that pierce through the skin of the host. Lone Star ticks are three-host ticks, feeding on different hosts during the larval, nymphal, and adult stages.
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