Between 2010 and 2020, more than 30,000 dengue cases were reported from four U.S. territories, with the highest number from Puerto Rico. Puerto Rico reported 199 deaths in 2012, the last time the country declared a dengue epidemic.
Dengue fever poses a significant public health threat in many parts of the world, particularly in areas with high mosquito populations and limited access to health care.
The Centers for Disease Control and Prevention said it is working with the Puerto Rico Department of Health and the Puerto Rico Vectored Virus Control Unit to monitor the virus and train health care workers. CDC also engages in clean-up campaigns and education efforts, using pesticides where appropriate.
Puerto Rico's Department of Health said it is working to increase surveillance, testing, vector control and outreach interventions.
“We are working on a community-based strategic approach. …What those interventions can do is [include]”Educational materials, site visits to identify environmental health risks, coordination with local governments to eliminate potential mosquito breeding sites, use of larvicides and adulticides,” said Chief Epidemiologist of the Puerto Rico Health Department. Melissa Malzahn said in an email.
What is dengue fever and how is it spread?
Dengue fever can cause high fever, severe headache, joint and muscle pain, rash, and in severe cases, death.
The virus that causes dengue fever infects 100 million to 400 million people worldwide each year, according to the World Health Organization.
The most common infection in humans is Aedes aegypti mosquito. Dengue fever is caused by four related virus serotypes, which are variants or strains of the virus. Mutations can affect the immune response to the virus, so infection with one serotype does not provide immunity to other serotypes. As a result, people can contract dengue fever repeatedly, increasing the risk of serious complications with each subsequent infection.
According to the CDC, about 1 in 4 people infected with dengue develop symptoms, and 1 in 20 people infected with the virus develop severe symptoms.
Infants, older adults, pregnant women, or people with weakened immune systems are at higher risk of developing severe symptoms.
Where is it most commonly found?
Dengue fever It is most common in tropical and subtropical climates and is prevalent in countries with temperate climates. Aedes aegypti Mosquitoes breed. The regions of Southeast Asia, the Western Pacific, the Americas, Africa, and the Eastern Mediterranean are particularly affected by dengue outbreaks. Countries such as Brazil, India, the Philippines, Indonesia, and Thailand have reported large numbers of dengue cases in recent years.
Albert Coe, an infectious disease physician and epidemiologist at the Yale School of Public Health, said Puerto Rico's continued spike in infections is unusual because virus transmission is typically low during the dry months.
“The fact that it's happening now is really a wake-up call and a warning sign for us. … Travelers are bringing the virus in and Puerto Rico is seeing an unseasonable outbreak, but this… That's really unusual,” Ko said.
Earlier this month, the Washington Post reported that Brazil had seen a surge in cases and many South American states had declared a state of emergency.
Public health experts say climate change and increased travel are making it easier for diseases to spread around the world, making diseases once believed to be contained to certain areas more prevalent. It said such spikes are likely to become more common.
“A good example is what we experienced with the Zika virus, which was also transmitted by the same mosquito, and traveler infections quickly spread the virus across the Americas,” Coe said. Ta.
There are no antiviral drugs to treat dengue fever. Instead, treatment includes supportive care such as ibuprofen, acetaminophen, and other nonsteroidal anti-inflammatory drugs.
“Symptoms can wax and wane, but overall they last for a few weeks, with the symptoms getting worse in the first week or so, and then over time you start to see some improvement,'' said Jack C. Ohoro. Stated. , an infectious disease physician at the Mayo Clinic.
Two vaccines are available for dengue fever. One is Dengvaxia, developed by Sanofi. The other is the dengue quadrivalent vaccine developed by Takeda Pharmaceutical Company. Both shots provide protection against all four dengue virus serotypes.
Dengvaxia is the only vaccine approved by the Food and Drug Administration for children ages 9 to 16. But one hurdle is that children must have evidence of previous infection shown in a blood test before they can be vaccinated.
Koh said studies have shown that people who have never been infected with dengue fever and have never been vaccinated are at higher risk of developing severe dengue fever if they become infected. The reason for this is that “protection against the four serotypes is incomplete (some serotypes are more common than others), so the problem is that in the event of a breakthrough infection, “This increases the risk of severe outcomes, including hospitalization, in people who were not infected.” Dengue fever. ”
Another vaccine, Qdenga, made by Japanese pharmaceutical company Takeda, has been approved in the European Union, the United Kingdom, Brazil, Argentina, Indonesia and Thailand. In July 2023, the company withdrew its application for FDA approval, citing “aspects of data collection that cannot be addressed” within the specified review schedule.
