Aedes aegypti mosquitoCourtesy Photo courtesy Centers for Disease Control and PreventionA re-emerging threat
Dengue fever is making a come back in South America and some fear it could become a problem again in the US as well. The year 2007 was an epidemic record-breaking year there was an 11% increase in reported dengue cases when comparing 2006 to 2007. Some even fear it could be spreading to the US. There was a recent article in the Los Angeles Times about it reappearing in the US.
What is dengue fever?
Dengue is a viral infection spread by the predominantly urban species Aedes aegypti mosquitoes. In recent years dengue has become a major international public health concern. Dengue is found in tropical and sub-tropical regions around the world, predominantly in urban and semi-urban areas.
Dengue fever is a severe, flu-like illness that affects infants, young children and adults, but seldom causes death. Dengue haemorrhagic fever is a potentially deadly complication that is characterized by high fever, haemorrhagic phenomena--often with enlargement of the liver--and in severe cases, circulatory failure.
Why is dengue making a come back?
Potential reasons include climate influences like global warming, El Niño / Southern Oscillation and La Niña, both of which influence the intensity and duration of the rainy seasons and hurricanes or induce intense droughts and damage to biodiversity. Another potential cause is population growth and increased opportunities for mosquitoes to breed.
On the other hand, micro factors exist that are dependent on the agent (virus) and the vector (mosquito)—which at times exhibits a growing resistance to insecticides—and the host, all of which closely influence the manifestation of the disease and its more serious forms.