Blood Sucking Bugs (Order Hemiptera; Suborder Heteroptera)

BLOOD SUCKING BUGS

FAMILY CIMICIDAE (BED BUGS)

The Cimicidae form a well-defined family of blood sucking bugs. They are oval flattened insects without functional wings, although the forewings remain present as two small pads on the dorsal surface of the thorax.

There are 91 recognized species of Cimicidae.

·         Most are associated with birds and/or bats but two species Cimex lectularius and Cimex hemipterus are the familiar bedbugs commonly associated with man.

·         Both species lay their eggs in cracks and crevices of houses and outbuildings.

·         Each female bedbug lays about 200 eggs, which hatch about after 10 days at 20 degree Celsius.

·         The nymphs and adults usually feed at night when their hosts are sleeping, although they will feed during the day if conditions are favourable.

·         Feeding behaviour, and hence development, is critically dependent on temperature and humidity.

·         Bedbugs do not feed at temperatures less than 13 degree Celsius.

·         Experimental evidences show that bedbugs can be infected with a range of human parasites and pathogens, including hepatitis-B, HIV and Trypanosoma cruzi.

·         Bedbugs will feed daily if given the opportunity and their high numbers can contribute to chronic iron-deficiency anaemia, especially in infants.

FAMILY POLYCTENIDAE (BAT BUGS)

The family polyctenidae comprises 32 species grouped in five genera. They are small ectoparasites of bats, with no known medical importance. They lack eyes and ocelli and are always flightless with forewings reduced to small flaps. The bugs are parthenogenetic. Bat bug Hesperoctenes.

FAMILY REDUVIIDAE & AND SUBFAMILY TRIATOMINAE (KISSING BUGS)

Most reduviidae are predators on insects and other invertebrates. They are predominantly tropical, occupying a very wide range of terrestrial habitats and displaying a variety of hunting strategies and pre preferences. Over 6000 species are known, which are grouped into 23 subfamilies. In many predatory reduviids, the fore legs are adapted to hold prey. Often the fore legs (sometimes mid legs) are strongly raptorial, equipped with spines, adhesive organs and/or glands secreting a glue-like substance.

Subfamily Triatominae (Kissing bugs)

There are 118 species of Triatominae recognized on the basis of morphological characters. They range from 5mm to 45 mm in length.

All species of triatominae are obligate bloodsuckers and over half have been shown naturally or experimentally to be susceptible to infection with Trypanosoma cruzi.

Epidemiologically only about a dozen species have become sufficiently closely associated with man to represent a public health problem; of these the most important vector species are Triatoma infestans, Panstrongylus megistus, Rhodnius prolixus, Triatoma brasiliensis and Triatoma dimidiata.

Other species are mainly associated with nest-building birds and small mammals, and occasionally reptiles.

 

References

·         Medical Insects and Arachnids Edited by Richard P. Lane and Roger W. Crosskey. Published in 1993 by Chapman & Hall ISBN 0 412 400006