Close to 1,000 people nationwide, including 23 in California, have been infected with a mosquito-borne fever this year, according to the World Health Organization.
Since the start of the year there have been a “significant magnitude” of dengue fever outbreaks in the Americas, with cases reaching just over 3 million, compared to last year’s numbers of 2.8 million, according to the organization.
Dengue fever is a mosquito-borne illness that mostly occurs in tropical and subtropical areas of the world and causes a high fever and flu-like symptoms. Its severe form, also called dengue hemorrhagic fever, can cause serious bleeding, with a sudden drop in blood pressure and death.
The fever is spread from a breed of mosquito, aedes aegypti, known as “ankle biters.” These mosquitoes also spread zika, chikungunya, and other viruses.
The organization also reported that, of the 3 million dengue cases in the Americas reported by July this year, 45 percent were laboratory confirmed, and less than one percent were classified as severe.
The report also states that the highest number of dengue cases to date this year are in Brazil, Peru, and Bolivia, with 1,302 deaths from dengue.
In a news briefing last month, the World Health Organization also described the latest spike in cases as a “canary in a coal mine”—meaning an early warning—relative to climate change and rising temperatures. Experts additionally say the mosquito’s population is likely to grow further in California in the wake of Hurricane Hilary in late August.
The aedes’ ability to spread diseases such as dengue fever and zika locally in the Golden State remains unknown. So far, cases found in California have been linked to travelers from abroad, according to vector control officials.
Travelers are urged to monitor themselves for signs of illness, wear mosquito-repellant, and stay indoors while symptomatic.
Symptoms of Dengue Fever
According to the World Health Organization, most infected with dengue will have mild or no symptoms. If they do occur, they usually appear between four and 10 days after a mosquito bite and last from two to seven days. Those infected typically improve in one to two weeks.Experts say symptoms include headache, high fever, muscle and joint pain, nausea, vomiting, swollen glands and rash and that severe cases are rare, which require medical intervention and can worsen rapidly.
There is no current dengue vaccine for adults. However, a pediatric dengue vaccine has been approved for children between the ages of 9 and 16 who have had a laboratory-confirmed previous dengue virus infection and are living in an area where it occurs frequently. Such areas, the CDC says, include the U.S. territories of American Samoa, Puerto Rico and the U.S. Virgin Islands.
How to Prevent Dengue Fever
Experts say the best way to prevent infection is to prevent mosquito bites. Recommended steps include wearing protective clothing, applying insect repellent with ingredients like DEET, Picaridin or IR3535, using mosquito nets, and using window screens.Regions like Orange County, New York have taken steps such as spraying insecticides in residential areas to prevent the spread and using drones to spray insecticides over wetlands and other areas prone to larvae and adult breeding grounds.
