Species: Rattus norvegicus

 

Identification: 12 - 18 inches long including tail (6-8inches long). Has coarse fur, brownish-gray on top and grayish below. Weighs around 195-485gms.

 

Behaviour: Usually found in markets, sewers, garbage dumps and places with poor sanitation. Other areas include storage rooms, basements, under building foundations and so on. Omnivorous; feed on nearly all types of food even garbage. Have a preference for high quality food like cereals, grains, meat, fish etc.

 

Life Cycle: Lifespan is around 12-18 months. Sexual maturity is reached within 3 months; and gestation period ranges from 21-23 days. Females can have 4-7 litters in its lifetime, each litter with around 8-12 baby rats.

 

Medical Importance: Vector of diseases like bubonic plague, Salmonellosis, Murine Typhus, rat-bite fever, and Leptospirosis.

 

 

 

Species: Rattus rattus diardii

 

Identification: Grayish-black to solid black in colour. 12-18 inches long, has a pointed snout and looks more slender and sleek than Norway rat. Its tail is longer than its body. Weight is around 5-9oz.

 

Behaviour: Usually located in trees, clinging vines on the sides of fences and houses, inside buildings in attic areas, ceiling or wall but prefers a vegetarian diet like fruits, nuts, seeds, ivy and vegetables.

 

Life Cycle: Gestation period is around 22 days, with females producing around 4-6 rat litters during its life, each litter comprising 4- 8 baby rats. Average lifespan is around 1 year.

 

Medical Importance: Carrier of several pathogenic bacteria like Bubonic plague, Salmonella spp, Murine and Scrub Typhus, rat-bite fever and so on.

 

 

 

Species: Mus musculus

 

Identification: Grayish brown in colour. Around 5 -7 inches long. Its tail is longer than its head and body combined. Weight is around 5/8 - 3/4 oz.

 

Behaviour: Usually found in houses and food stored in urban areas. They nest in cabinets, furniture, behind rafters and storage areas. Main diet comprises many kinds of plant material like seed, cereal grains, fleshy root, leaves and stems. Likes to nibble small amounts of food at frequent intervals.

 

Life Cycle: Reaches sexual maturity in 5 -7 weeks and has an average gestation period of 19 days. Females can have 5-10 litters per year and each litter consists of 3-12 baby rats. Lifespan is around 12-18 months.

 

Medical importance: Contamination may occur with their droppings and spread diseases like Murine Typhus, Rickettsial pox, Tularemia, food poisoning and Bubonic plague.

 

 

 

Species: Aedes aegypti

 

Identification: Have black and white stripes that can be found on its legs and body. Have two parallel white stripes on its thorax.

 

Behaviour: Day biter, with peak biting times occurring in the early morning and late afternoon. Mainly breed indoors in flower vases, potted plant bases, gull traps, pails, roof gutters and other sources of stagnant water. Eggs can resist desiccation for up to 1 year.

 

Life Cycle: Around 7 -10 days. Females can produce more than 700 eggs in 15 batches over a 2 month period. Life span is around 2-3 weeks

 

Medical Importance: Vector of the deadly diseases like Dengue Haemorrhagic Fever and Yellow Fever.

 

 

 

Species: Aedes albopictus

 

Identification: Has black and white stripes that can be found on its legs and body. Has single white stripe on its thorax.

 

Behaviour: Day biter. Peak biting times occur just after sunrise and before or immediately after sunset. Mainly found breeding outdoors in both natural and artificial containers like tree holes, bamboo stumps, canvas sheets etc.

 

Life Cycle: Around 7-10 days. Females can produce more than 700 eggs in 15 batches over a 2 month period. Life span is around 2-3 weeks.

 

Medical Importance: Vector of the deadly diseases like Dengue Haemorrhagic Fever but not as deadly as the Aedes Aegypti as it is not as good a carrier of the disease.

 

 

 

Species: Culex quinquefasciatus

 

Identification: Uniformly brown in colour. Bigger in size as compared to the Aedes mosquito.

 

Behaviour: Night biter. Most active biting period is between midnight to 3am both indoors and outdoors. Prefers to breed in organically polluted water, for example, septic tanks, ground puddles, choked drains, and small receptacles containing polluted water.

 

Life Cycle: Around 7-10 days. Average life span is around 2 weeks.

 

Medical Importance: Bite can cause pain and irritation to one’s skin. Vector of diseases like lymphatic filarisis or elephantiasis.

 

 

 

Species: Blattella germanica

 

Identification: 13 - 16mm long fully grown. Light brown to tan in colour with two parallel, dark longitudinal stripes which can be seen on it s body.

 

Behaviour: Found mostly in warm and humid areas such as kitchens, bathrooms, basins, brains, behind refrigerators and stoves, and in cabinets etc. They spend 75% of their time hiding in cracks and crevices and feed on any kind of organic materials.

 

Life Cycle: Average life cycle of 3 months. Lifespan is around 3-7 months. Females can lay up to 5-7 egg cases in their lifetime with each egg case containing around 30-40 eggs.

 

Medical Importance: Vector of various pathogenic and food poisoning bacteria, for example, salmonella spp and is a main cause of allergy in humans.

 

 

 

 

 

Bed bugs feed mainly on the blood of humans, but also suck blood from other animals, birds and bats. Bed bugs usually feed at night when people are asleep. As they feed, they inject a salivary secretion into the wound to prevent coagulation. This fluid often causes the skin to itch and become swollen. Scratching causes sores which may become infected. Bed bugs are not known to transmit human pathogens, including hepatitis B and HIV.

 

The adult bed bug is brown, ovoid in shape, and has no wings. It is about 1/4 inch long. The newly hatched bugs are almost colourless and similar to the adult except they are much smaller. After a meal of blood, the body becomes swollen and the colour changes to dark red.

 

During the day, bed bugs hide in cracks in the walls, behind baseboards, wallpaper and pictures, where parts of a bed are joined together around slats, around the tufts of mattresses and in the bed clothes. They have a sweetish, foul odour which is caused by an oily liquid they emit. Bed bugs are carried into homes in clothes, second hand beds and bedding, furniture, suitcases, or by other people.

 

Bed bugs lay eggs that are 1/25" long and are slightly curved. They are usually deposited in clusters. They are fastened with cement to cracks and crevices or rough surfaces near adult harborages.

 

The eggs hatch in 4-12 days. The newly hatched nymph is straw colored before feeding. After getting a blood meal, the nymph turns red or purple in color because of the blood in its body. There are 5 nymph stages, and it usually takes 35-48 days for nymphs to mature.

 

Female bed bugs deposit 3 to 8 eggs at a time. A total of 200-500 eggs can be produced per female. The eggs hatch in 4-12 days. Adult bed bugs can survive for 6-7 months without a blood meal and have been known to live in abandoned houses for 1 year. In some cases they survive without humans by attacking birds and rodents.

 

Steam cleaning of infested mattresses is effective in killing bed bugs living in seams and buttons. Cracks harbouring bed bugs can be treated with residual sprays. A flushing agent containing a pyrethrin can be used around cracks and crevices to locate bed bugs and force them into the open for easier treatment.

 

Take the bed apart. Spray the bed frames, slats and springs with enough spray to thoroughly wet them. Pay particular attention to the tufts and seams of the mattress. Spray the woodwork and all walls in the bedroom at least 2 feet above the floor. Brush, vacuum, and steam clean mattress and pillows, then put on clean sheets and pillow cases.

 

Spray again if there are any new signs of bed bugs. After 2 weeks, spray the bed, furniture, and walls again.

 

 

 

Species: Musca domestica

 

Identification: Dark grey in colour with 4 black stripes on its thorax. Has grey or yellowish abdomen with dark midline and irregular dark marking on sides. Measures 1/8 -1/4 inch in length.

 

Behaviour: Breeds in warm, moist decomposing materials like animal dung, garbage, animal carcasses, sewage compost etc. They are attracted to a particular medium by the smell of carbon dioxide, ammonia and other odour.

 

Life Cycle: Approximately 10-21 days. Females can lay as much as 75150 eggs each time and up to 5-6batches of eggs during its lifetime. Average lifespan is around 2-4 weeks.

 

Medical Importance: Vector of diseases like typhoid fever, cholera, dysentery, anthrax, and tuberculosis.