In fact, mosquitoes carrying dengue fever have invaded more than a third of the homes in Argentina's most populous province, a doctor said last week. The aedes aegypti mosquito appeared in Argentina in 1986 and is now being found in 36 percent of homes in Buenos Aires province, according to Dr. Alfredo Seijo of the Hospital Munoz. The province is home to 14 million people. Malaria currently kills up to 2 million people each year and over 2 billion people are considered at risk of contracting the disease. Hot, humid periods in the 1990s have led to malaria cases being recorded in the United States in California, New Jersey, New York, Texas, Georgia, Florida, Michigan and Virginia, as well as in Toronto, Canada.
Analyses show malaria outbreaks outside tropical regions becoming more common in the future.
The seven warmest years since scientists began keeping records almost 150 years ago have all occurred in the past decade with 1997 being the warmest. Every month from January to August in 1998 broke the previous record for that month. The problem will be worsened by global warming affecting the population balance of animal predators such as owls, snakes, birds and bats, animals that keep insects and rodents in check. At the same time, extreme droughts turned forests in Asia, the Mediterranean region, Mexico, Central America, Florida and California into tinderboxes. Meanwhile, floods which affected Africa in late 1997 led to upsurges of cholera, malaria and Rift Valley fever.