Recently, dengue fever infection is increasing as the mosquito habitat expands and the population increases due to the influence of climate change. In particular, as the number of infected patients is increasing, especially in the United States and Southeast Asia, special attention needs to be paid to domestic and foreign tourists and visitors visiting the region.
According to the World Health Organization (WHO) on the 22nd, as climate change has widened the route of dengue fever infection, half of the world’s population is at risk of contracting dengue fever. Dengue fever, which has 100 million to 400 million people infected each year, is particularly affected by the United States, Southeast Asia, and the Western Pacific region, with Asia accounting for 70% of them.
Dengue fever is an acute febrile illness that infects more than 100 million people each year and causes symptoms including headache, high fever, rash and body aches. In the case of children, it can lead to severe symptoms such as dengue hemorrhagic fever or dengue shock syndrome, which bleeds throughout the whole body, and in severe cases, it leads to death.
Recently, as the number of foreign travelers has increased, the number of infected patients in Korea has also increased. Among the four mosquito-borne infectious diseases classified by the Korea Centers for Disease Control and Prevention as infectious diseases to watch out for when traveling abroad, such as dengue fever, malaria, zika virus infection, and chikungunya fever, the number of dengue fever patients this year the highest number was recorded, namely 46 (on the 2nd of this month). The majority of them were confirmed to be infected in Southeast Asian countries such as Vietnam, the Philippines, and Thailand. In response, the Korea Centers for Disease Control and Prevention (KCDC) announced on the 22nd that it would gradually include dengue fever and measles among the current 11 infectious diseases subject to quarantine through the ‘Basic Control Plan’ Quarantine 1st’.
The number of infected patients is also increasing in the US autonomous territories where Korean tourists visit. According to the Washington Post on the 21st (local time), more than 96% of the 31,000 cases of dengue fever in US territories reported to the Centers for Disease Control and Prevention (CDC) between 2010 and 2020 occurred in Puerto Rico, and territory of the United States. American Samoa, the US Virgin Islands and Guam followed. The CDC emphasized the need for increased prevention of dengue infections in US territories.
Until now, most cases of dengue fever in the United States occurred in travelers visiting Pacific island countries such as Tonga and Fiji, or Central and South American regions such as Brazil and Argentina. Recent travel, trade, urbanization, and climate change have led to the spread of dengue fever mosquitoes in temperate regions, and new reports are reported every year in temperate regions.
Half of the cases of dengue fever in the United States over the past decade have been reported to be under the age of 20. However, the vaccine currently in use in the United States is Sanofi Pasteur’s ‘Dengvaxia’, which was approved by the Food and Drug Administration (FDA) in January.
Qdenga, developed by Takeda Pharmaceutical of Japan, is a preventive vaccine that can be injected before infection and is already approved for use in Europe and Brazil, and is currently under review by the FDA . US researchers claim that vaccination alone in Puerto Rico could prevent 3,000 hospital admissions within 10 years, and a dengue vaccine being developed could help a wider age group and those without a history of infection.
In addition to vaccines, various methods for preventing dengue fever are being developed. The US CDC is conducting research to reduce the fertilization of mosquitoes that cause dengue fever by releasing mosquitoes infected with Wolbachia bacteria in Florida and Texas, where dengue infections are on the rise. It is a virus that blocks the replication of the dengue fever virus and is a method of reducing the population by modifying the gene of mosquitoes.
This is a genetic modification technology developed by Oxitec, a British bio company, and has previously successfully eradicated mosquitoes that spread dengue fever in Brazil last October. Oxitech research has confirmed that the release of modified mosquitoes can significantly reduce the risk of dengue and Zika viruses carried by female mosquitoes.
The World Health Organization is also supporting International Atomic Energy Agency (IAEA) research to block dengue fever using radiation. The IAEA has developed the so-called ‘insect sterilization method (SIT)’, which breeds large numbers of male insects and kills them with radiation, and is conducting mosquito control experiments in South Africa and Mauritius. Its purpose is to eliminate the possibility of spreading dengue fever by releasing male mosquitoes that have lost their ability to breed with special radiation effects. SIT technology has been applied to crop damaging insects.
“Given the history of farmers using SIT to eradicate pests, we believe this technology could also be used to fight mosquito-borne diseases in humans,” said Randall Nett, CDC Director of Arboviruses (Arthropod-Transmitted Viruses such as Dengue Fever and Zika) I’m looking at it,” he said.
