New Report: Dengue Fever a Looming Threat in the United States

Two types of mosquitoes capable of transmitting the dengue fever
virus are invading Southern and Mid-Atlantic states, creating
conditions more favorable for an outbreak, according to a report
released today by the Natural Resources Defense Council. Areas of the
United States previously inhospitable to the disease now support
populations of mosquitoes capable of carrying the virus - a problem
that may worsen with global warming. An estimated 173.5 million
Americans live in counties that now contain one or both of the mosquito
species.

"Milder winters, hotter, wetter summers and
even droughts can bring this insect-borne threat closer to home," said
Dr. Kim Knowlton, NRDC senior scientist. "Usually relegated to tropical
and exotic locales, dengue fever has rarely been an issue in the United
States outside of the Texas-Mexico border region. But a changing
climate may allow certain species of dengue-spreading-mosquitoes to
flourish in nearly half of the United States."

NRDC's report, "Fever Pitch: Mosquito-Borne Threat Spreading in the Americas,"
finds that mosquitoes capable of transmitting dengue have spread into
at least 28 US states, including Texas, Florida, Arizona, and even
states as far north as New York and New Hampshire.

In
the United States, the number of physician-reported cases of the
disease has more than doubled in the past decade. Nearly 4,000 cases of
imported and locally-transmitted dengue were reported to the Centers
for Disease Control and Prevention (CDC) between 1995 and 2005, and
when the Texas-Mexico border region is included, the number jumps to
10,000 during that time.

International rates of dengue
infection have increased 30-fold in the last 50 years, to an estimated
50 to 100 million infections, a half-million hospitalizations, and
22,000 deaths annually in more than 100 countries. In Mexico, Central
and South America more than 900,000 dengue fever cases were reported in
2007.

Many factors may be contributing to the rise in
dengue fever, including increasing international travel and trade,
densely-populated communities living in poverty in many countries
including the United States, and the effects of global warming.
Researchers project that because of global warming, in the next 75
years 3 billion additional people will become at risk for the disease
across the globe.

Known as "Breakbone Fever" because of
its classic symptoms, dengue is characterized by agonizing aching in
the bones, joints and muscles, a pounding headache, pain behind the
eyes, a high fever and a classic rash. There is no cure or vaccine
against the virus, only preventative and supportive care.

Both
large-scale and individual actions can reduce the spread of dengue
fever. Individuals can protect themselves and their families from
mosquito-borne illnesses by wearing loose-fitting long sleeves and
pants when outdoors and using DEET (not more than 30%) on exposed skin
when the bugs are biting. Individuals can also make sure windows and
doors have tight fitting screens and that they don't leave open
containers of water in or near their homes. Further precautions should
also be taken while traveling to countries where dengue fever is
already established.

At a national and international
level, strong climate legislation is needed to slow global warming.
The Centers for Disease Control and Prevention (CDC) should require
reporting of dengue fever so the spread of the disease within the US
can be accurately tracked. NRDC's report recommends that local and
national governments train clinicians, share surveillance data, enhance
lab capacity, and coordinate with international partners to prevent
future outbreaks and reduce the threat to public health.