They are bloodsucking endoparasites of reptiles, birds and mammals. Their Taxonomic status is usually uncertain as its larvae resembles those of the mites.
Physiology and Structure:
- Adult pentastomids are white, cylindrial or flattened parasites that have two distinct body regions: an anterior head (cephalothorax) and abdomen.
- The adults are elongated and can grow up to 1cm to 10cm. The head has a mouth and two pairs of hooks.The abdomen may appear annulated but it is not segmented. They own digestive and reproductive organs but lack circulatory and respiratory systems.
- As adult pentastomids are found in lungs of reptiles and the nasal passages of mammals, many verbrates including humans may serve as intermediate hosts. Contamination of vegetation or water can occur when embryonated eggs are discharged in the feces or respiratory secretions of the infected definitive host which leads to ingestion by fish, rodents, goats, sheep or even humans.
- The eggs then hatch in the intestine and the larvae penetrate the intestinal wall which attracts to the peritoneum. As it matures, it develops into infective larvae, encyst in viscera or die and become calcified. Also, humans can be infected after comsuming the inadequately cooked flesh of infected reptiles or by eating infected flesh of, example, goats or sheep that contains infective larvae. As the larvae mugrate from stomach to the nasopharyngeal tissues, where they develop into adult pentastomids and produces Halzoun syndrome.
Halzoun syndrome is caused by the attachment of adult pentastomes to the nasopharyngeal tissues. Usually, sneezing, violent outburst of coughing and vomitting.
It is made by identifying a pentastomid in a biospy specimen obtained at surgery or at autospy. In most cases, calcified larvae can be observed on x-ray flims of abdomen ot chest that provides a presumptive diagnosis.
Treatment, Prevention and Control:
In symptimatic patients, undergoing surgery can remove encysted parasites.
Preventive measures such as thotough cooking of meat and vegetables and also avoid drinking contaminated or unboiled water.