A female House Fly can lay between 500 and 600 hundred eggs during her life.


Several insect species are notorious carriers of diseases and, in the past, have been responsible for epidemics that have decimated human populations. Many of them continue to cause major problems in some parts of the world.


The Common House Fly is the world’s most dangerous bug. They travel continuously between human food, rubbish, and both human and animal excrement. Each fly can carry as many as six million bacteria on its feet. The list of diseases they spread includes many of the worst killers of humankind: typhoid, cholera, gangrene, tuberculosis, gonorrhoea, bubonic plague, leprosy, hepatitis, diphtheria, scarlet fever, anthrax, amoebic dysentery and poliomyelitis.

Flies not only transmit diseases, but also the eggs of parasitic worms to our mouths. Most of these infecting organisms thrive in the warm, moist, nutrient-rich environments of our digestive systems, multiply rapidly and may invade other parts of our bodies.


Mosquitoes are responsible for the deaths of 2.7 million people each year. They are able to spread a huge range of diseases including malaria and dengue fever. In Australia, mosquitoes carry a range of parasites and viruses such as encephalitis, dengue fever and Ross River fever. Only female mosquitoes suck blood, which is necessary for the development of their eggs. It is also only female mosquitoes that make a buzzing sound as they fly.


Lice were among the most dangerous of all insects until the mid-twentieth century. They were transmitters of typhus—a debilitating and deadly disease that was particularly prevalent in Europe. Lice epidemics plagued high density human populations, such as in prisons and armies. During World Wars I and II, lice were responsible for the deaths of over 6 million people. The last typhus epidemic occurred in Naples in 1944 and was eventually controlled by dusting three million people with insecticides.


In 1347, Oriental Rat Fleas, carried by Black Rats, introduced the bubonic plague into Europe. Called ‘The Black Death’, this was one of the worst human disasters in history. The disease struck and killed with incredible speed. It ravaged the cities, caused widespread hysteria and ultimately claimed 25 million lives—one third of the population of Europe.

Wasps, Bees & Ants
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Common House Fly, link to large image Common House Fly

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Head Louse, link to large image Head Louse

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