Phylum arthropoda divided into Insecta head thorax abdomen
Phylum arthropoda divided into • Insecta: head, thorax, abdomen, 3 pairs of legs, 1 pair- antennae ü mosquitoes, house fly, louse, flea • Crustacean: cephalothorax, 5 pairs- legs, 2 pairs- antennae, mostly aquatic. Cyclops • Arachnida: 4 pairs legs, head, cephalothorax, abdomen ü Ticks, mites
Vector • Arthropod capable of transmitting disease either mechanically/biologically through: ü Direct contact ü Mechanical contact ü Biological Ø Propogative: plague bacilli Ø Cyclo-propogative: malaria parasite Ø Cyclo-developmental: filarial parasite
Mosquito • • Anopheles: A. culcifacies, A. stephensi- malaria Culex: C. fatigans-filaria, JE Aedes: A. aegypti- dengue, yellow fever Mansonia- rural filaria
Anopheles egg • • Laid separately Boat shaped Lateral floats present Clean water
A. larva • Floats horizontal/ parallel to surface of water • Palmate hairs present on abdominal segment • Respiratory apparatus- in the form of 2 apertures in a level with body surface
A. pupa • Short, broad respiratory tube on cephalothorax • Body: deep coma shaped
A. Adult male • • Palpi= proboscis Tip: club shaped A pair of antennae Spotted wings
A. Adult female • • Resting position makes an angle with surface Palpi= proboscis Tip not club shaped Antennae- small hairs
Culex egg • • Egg rafts – 200 clusters No lateral floats Single cigar shaped, Polluted/ clean water
C. larva • Rests obliquely/ inclined to water surface • Palmate hairs absent • Respiratory apparatus- in the form of prominent protruding tube- Respiratory siphon
C. pupa • Long, tubular slender respiratory ( siphon) tube on cephalothorax • Ordinary comma shaped
C. Adult male • Palpi> probscis • Feathery antennae • Abdomen, head, thorax makes an angle with proboscis parallel to surface
C. Adult female • Palpi< proboscis • Less hairy antennae
Anopheles • Public Health Importance: malaria • Control measures: Antilarval and antiadult measures ü Adult spraying with DDT, pyrethrum ü Mosquito nets ü Mosquito repellants
Culex • Public Health Importance: urban filariasis, Japanese Encephalitis • Control: Anti adult : pyrethrum extract • Mosquito nets, repellants • Drainage- larval control.
Sandfly • Egg: ü Damp, dark places ü Large, torpedo shaped • Larva: ü head, neck, 12 body segments- elongated ü Conspicuous head, chitinised ü Hair- seen at head ü Hairy body segments
Pupa • Cephalothorax present • Upward curved abdomen • Last moulted skin attached to tip of abdomen
Adults • • Smaller than mosquitoes Wings: upright Legs longer body Hairy insect
• Public Health Importance: kala azar • Control: ü Cracks and crevices: plastered ü Sulphur fumigation/ formalin, DDT ü Repellants: dimethylphlate ü Sandfly nets
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