Mosquitoes are unfortunately an annoying reality in most tropical or hot countries; Pakistan is no different. But whereas in countries such as Africa, India & Thailand travellers are mostly worried about contracting Malaria, in Karachi the most dangerous threat is DENGUE FEVER.
Dengue is a disease transmitted worldwide by mosquitoes. Depending on your immune status, infection can manifest as a severe but non fatal viral syndrome or a rapidly progressive & a frequently fatal haemorrhagic fever. The most frequent clinical signs & symptoms are fever, vomiting and abdominal pain. The term "dengue" is a Spanish example of the Swahili phrase "ki denga pepo" meaning "cramp-like seizure caused by an evil spirit". This expression emerged during an outbreak in the Caribbean in 1827.
One of the first major Dengue Fever epidemics in Karachi occured in the year 1997. In 2006 the fever made a come-back & claimed 50+ lives with over 4,500 infected individuals. It was spread across the region by its small "blood-maidens of terror": the female mosquito. (males don't suck blood)
So, how do you protect yourself?
There is currently (2007) no effective vaccine available on the world market.
Use mosquito nets, repellents, cover exposed skin, use DEET-impregnated bednets and avoid endemic areas. Mosquitoes "swarm" and are most active during dusk, so it's important to stay indoors whilst the sun is setting or to protect yourself with the afore-mentioned methods.
There are mosquitos all over the place in Karachi, especially in the evenings, so be sure to wear a mosquito repellant, or atleast get a mosquito repelling coil, for when you sleep,especially.
It lessensyour exposure to annoying bites, and reduces the risk of catching anything from the mosquitos.