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maybe that’s why I reacted the way I did,” he says of the raised welts with which he was covered from head to toe. “They resembled large mosquito bites and took several days to disappear,” Miller says. Both Miller and Needham recovered quickly and continue to swim and enjoy the outdoors, though both are now more likely to heed health warnings at swimming sites. Needham, who’s “more of an ocean guy anyway,” says he won’t be swimming in that particular lake again, and off ers a good rule of thumb for deciding whether to enter a particular body of water: “Don’t swim in a lake unless it’ll take you a while to get across it, as small and slower moving bodies of water are more likely to harbour crit ers that will bother you.”


PERHAPS THE MOST REVILED WATER-LOVING INSECT IS THE MOSQUITO


CATCHING THE BUG We oſt en say someone has caught the open water swimming bug when they begin spending lots of time swimming outdoors. But that contagion can be something of a two-way street; some ‘bugs’ catch us, and aquatic insects and invertebrates can be among the most annoying – and, in some cases, potentially dangerous – around. Let’s take insects fi rst. As the most populous and ubiquitous of earthly animals, every continent has its share. Of the millions of species of insect, many are well adapted to aquatic and semi- aquatic environments – the very environments in which open water swimmers frolic, train and compete. Perhaps the most reviled of these insect is the mosquito. Mosquitoes breed in stagnant, standing water and are a mainstay of calm ponds, lakes, and river beds – all of which can be the most enticing of locales for a summertime dip. But swimmer beware: those serene set ings can be home to scores of female mosquitoes looking for their next meal. As egg- laying time approaches, female mosquitoes supplement their nectar-based diets with high-protein blood from other animals. In addition to the itchy, red welts most of us develop aſt er a bite, mosquitoes are also disease vectors, and can pass several blood- borne diseases on to their prey – an inequitable trade for your blood. Malaria is the most deadly of the diseases mosquitoes can carry. It is prevalent in all tropical regions and an expanding range of non-tropical regions, too. According to statistics published by the World Health Organization in its 2011 World Malaria Report, more than 655,000 people worldwide died of malaria in 2010. Of these deaths, 91% occurred in Africa, a place where mosquitoes are abundant and preventative measures not always available. By comparison, that year a mere 200 cases of malaria were reported in Europe, resulting in zero deaths, while 1 million cases were reported in the Americas, leading to 1,000 deaths. While malaria gets a lot of at ention globally, it’s not the only disease that uses the mosquito as its vector. Recently in the eastern United States, the big concern has been West Nile Virus, a disease fi rst discovered in Uganda in the 1930s that found its way to New York City in 1999.


Birds are carriers of the disease, and when a mosquito bites an


infected bird – and then bites a human – transmission can occur. Most cases of infection are mild, resulting in three to six days of fl u- like symptoms, but in more severe cases, West Nile can develop into encephalitis or meningitis, a potentially fatal infection of the brain. Another mosquito-borne ailment is Ross River Fever, an


An electron microscope image of the West Nile Virus, which is mosquito borne


infectious disease characterised by a fl u-like illness and arthritis. The virus is endemic to Australia, Papua New Guinea, Fiji, Samoa, the Cook Islands, New Caledonia and several other islands in the South Pacifi c. 


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