World Health Organization statistics show that the incidence of dengue fever Zui has increased dramatically in recent decades worldwide, and the disease is now endemic regionally in more than 100 countries. Among them, South-East Asia, the Americas and the Western Pacific region are seriously affected by Zui.

　　In Southeast Asia, dengue outbreaks occur almost every year, but this year the situation is particularly fierce: the number of cases in the Philippines, Vietnam, Malaysia, Bangladesh and other countries is significantly higher than the same period last year, and the epidemic still shows no signs of slowing down.

　　Why is it popular?

　　Dengue fever is an acute infectious disease caused by dengue virus. Patients with persistent fever, severe headache, muscle pain, joint pain and other symptoms, accompanied by loss of appetite, nausea, vomiting and rash, serious cases will die.

　　After entering the rainy season in Southeast Asia, abundant precipitation has brought favorable conditions for mosquito breeding. When mosquitoes bite people with dengue fever or recessive infections, the virus replicates in large numbers in mosquitoes. When mosquitoes bite other people, the virus spreads.

　　A study published last year in the Lancet found that the number of dengue fever cases has nearly doubled every 10 years since 1990 due to climate change. Another study, published in the British Journal Nature Microbiology, argues that urbanization and mass migration contribute to the spread of dengue fever.

　　Is the vaccine useful?

　　According to the WHO official website, there is no specific treatment for dengue fever at present, and early detection and appropriate care can reduce the mortality rate to less than 1%.

　　Dengvaxia, developed by French pharmaceutical company Sanofi Pasteur at the end of 2015, is the world's first dengue vaccine, but it is only suitable for people who have suffered from dengue fever to prevent re-infection. It can not be used for people who have not suffered from dengue fever before. For those who have never been infected with dengue fever, if they are infected with dengue fever after vaccination, they may cause more serious symptoms.

　　Peter Marcos, director of the Center for Biological Product Assessment and Research of the Food and Drug Administration of the United States, explained that when a person is infected with a certain type of dengue virus, he is usually immune only to that type of virus, and then if infected with other types of virus, it may lead to serious illness.

　　Mosquito control is the key

　　Preventing mosquitoes is very important to prevent dengue fever.

　　WHO recommends that Zui use mosquito nets better when sleeping, and use screens or close doors and windows to prevent mosquitoes from entering the room. As far as possible do not let the skin exposed, wearing light color, long sleeves, slightly loose pants, more compact clothing fabric Zui is ideal. This is because mosquitoes are more susceptible to dark colors such as blue, green and black. Clothing that is tight and sparse still gives mosquitoes a chance.

　　Some mosquito eggs can survive for up to a year without water, and a small amount of water is enough for them to develop into larvae. Therefore, it is particularly important to clean up the accumulated water and prevent and control it from the source. WHO recommends that containers, such as buckets, flower pots or car tyres, that may store water (even a small amount of water), be emptied to keep them clean or covered, leaving mosquitoes nowhere to breed.

　　WHO recommends the use of mosquito repellents on skin or clothing, which should contain "DEET" ingredients. It is also safe for pregnant women and fetuses to use mosquito repellents at the recommended doses in the product instructions. According to the length of outdoor stay, mosquito repellent products with different concentrations of DEA can be selected. After using 30% mosquito repellent solution, the effective time of mosquito repellent can reach 6 hours.

　　A spokesman for Thailand's Ministry of Public Health, Opa, pointed out that mosquitoes that transmit dengue virus mosquitoes are mostly active during the day. Tourists should try to avoid entering and leaving forests and waterfalls in rainy season when they are outdoors in dengue-endemic areas.