"Malaria-bearing mosquitoes mainly feed at night, and tend to return to the same location for blood meals. The more people who sleep in one area, the greater the likelihood of an infected mosquito spreading the parasite to a new, uninfected victim."
"It is a common misconception that malaria is a tropical disease, and with 90 per cent of malaria deaths taking place in Africa, it is easy to see why people believe this," said McKitrick.
"But historically, malaria has occurred in all climate zones including the Arctic, and was endemic in North America and Europe a hundred years ago. In many cases, the disease disappeared even in countries that made no efforts to fight it, while others that tried to eradicate it failed. We found declining average household size key to explaining this pattern. "
As household size continues to decline, said McKitrick, malaria should gradually disappear. But countries need not wait for that to happen. "The key factor is segmenting sleeping quarters and greater use of bed nets in those countries where malaria is still prevalent," he said.A related story reveals that malaria would be essentially non-existent in the US if people didn't contract it outside the country and then bring it back with them. And why does that happen? "Travelers can protect themselves by taking malaria drugs before and during a trip. Only a fraction of the 2011 cases took the right drugs." A sad commentary on the sanity of travelers.