3. Bug
Distribution: Cosmopolitan
Habit/ habitat: Many live on plants. Many are adapted for
aquatic life. Few are parasitic and blood suckers.
• Only 2 groups are of public health importance. These are:
1. Cimicidae- Cimex lectularius, C. hemipterus
2. Reduviidae Tratoma
• Cimex (Bed bug): These are ectoparasite and feed upon
human blood and found all over the world.
Habitat:
• it usually inhabits the old buildings, hotels, cinema halls
other halls, carriages, and other human dwellings
particularly dark and damp places. They are so clever in
hiding. They are nocturnal. If direct approach is checked
they usually climb the walls and ceiling to drop down on
the bed. They can live without food for a year.
4.
5.
6. Morphology
• Body is oval and dorso-ventraly flattened. They are about 4-
7 mm. They are reddish brown in color. They are pale
yellow/brown when unfed and darker brown after blood
meal. Its body is divided into 3 parts i.e. Head, thorax and
abdomen
• Head: It is short and broad. It bears a pair of antennae, 1
pairs of compound eyes and a beak or proboscis. Mouth
parts are piercing and sucking type. Proboscis is the main
sucking apparatus.
• Thorax: It is 3 segmented. The prothorax is much larger
than mesothorax and metathorax and has distinct wing like
expansion. There are 3 pairs of clawed legs. The legs are
slender but well developed. A pair of vestigial wings is
present. Hind wings are absent.
7. • Abdomen: It is flat with 8 visible segments. In males it
is pointed at the tip but the female is broader.
• Life history: Its life history includes eggs, nymph and
adult. The eggs hatch into nymphs in 6-10 days. The
nymph is like adult except that it is smaller and pale in
color. It feeds on blood and after 5 moults (interval of
8 days) it becomes adult.
PH importance:
• 1. Restlessness in night
• 2. Iron deficiency in infants (India)
• 3. Hip. B virus (Africa)
8. Control
1. Detection – by characteristic unpleasant smell
2. Repellents
3. Simple household measures – cleaning infested articles
4. Sundrying
5. Nets
6. Smoke generators
7. Residual insecticides- malathion (2%), Fenithothion 0.5-1,
propoxur 2, carbryl 1, diazinon 0.5, bendiocarb 0.2-0.3, permethrin 0.5,
cyfluthrin 0.01, deltamethrin 0.005
8. Fumigation of the houses with sulphur, HCN, methyl bromide
9. Houses should be well ventilated
10. Cracks and crevices in the building or furniture should be filled up
9. Reduviidae
Family- Reduviidae (reduviid bug or cone nosed
bug)
• Panstrongylus(Triatoma) mejistus – in Brazil
• P. geniculatus – in Panama, Brazil. S. America
• They are also known as cone nosed bug or
Assassin bug or Kissing bug. They live in
cracks and crevices of mud walls, other hiding
places in walls and ceiling, in animal
habitations and nests. They emerge only to
feed and then retreat into their hiding places.
10. Morphology
• 3 parts-
• Head - Its head is elongated, snout like and cone
shaped. It bears a pair of prominent dark colored
eyes, 1 pair of laterally situated long antennae
and a proboscis (rostrum).
• Thorax -The dorsal part of first segment of thorax
consists of very conspicuous triangular
pronotum. The adult has wings. They can fly for a
considerable distance in the house.
• Abdomen -The abdomen is oval in shape. Size is
about 2-3 cm (1inch) in length.
11.
12. PH importance
• Their bites may cause intense itching, nausea, flushed
face, palpitation of the heart.
• They transmit Trypanosoma cruzi, the causative agent
of chagas’ disease (American sleeping sickness)
• Control;
• 1. House improvement
• 2. Application of insecticides to house walls
• 3. Improvement of peridomestic environment
• 4. Net
• 5. Fumigant cansisters
