A person can get dengue fever multiple times.

Associate Professor, Dr. Tran Dac Phu, Director of the Department of Preventive Medicine (Ministry of Health) said that many people have the mentality that if they get dengue fever once, they don't have to worry about getting it again. In fact, a person is at risk of getting dengue fever four times with four types of the virus, and the next infection is often more severe than the previous one.

Associate Professor, Dr. Tran Dac Phu said that a person is at risk of contracting dengue fever multiple times, with different types of the disease. Photo: H.Hai

According to Associate Professor Phu, dengue fever is an acute infectious disease that can cause epidemics caused by the Dengue virus with 4 pathogenic types denoted as D1, D2, D3, D4. Because the immunity created after contracting the disease is only specific to each type, people can contract dengue fever a second or third time from different virus types.

“Once you have contracted a type like D1, you will have lifelong immunity to it. Subsequent infections tend to be more severe than the previous one,” said Associate Professor Phu.

Where do mosquitoes that cause dengue fever like to live?

The disease is spread by Aedes mosquitoes biting infected people and then transmitting the disease to healthy people through bites.

Many people mistakenly believe that mosquitoes in cowsheds… bite and cause dengue fever. In fact, that is a type of mosquito that transmits other diseases, while dengue mosquitoes like to live near people, hiding right next to them. The two types of mosquitoes that transmit the disease are Aedes aegypti and Aedes albopictus, of which Aedes aegypti is the main cause.

Female Aedes mosquitoes bite people during the day, biting most strongly in the early morning and late afternoon. Aedes mosquitoes often rest in dark corners of the house, on clothes, blankets, clotheslines and household items. Aedes mosquitoes lay eggs and reproduce mainly in clean water containers in and around the house such as water tanks, jars, pots, wells, tree holes... objects or waste containing water such as flower vases, bowls of water on the cupboard, tires, coconut shells..., do not lay eggs in stagnant ponds or sewers with foul-smelling water. Aedes mosquitoes thrive in the rainy season, when the average temperature exceeds 20ºC.

In Vietnam, since the beginning of the year, nearly 60,000 cases of dengue fever have been recorded, of which more than 50,000 cases have been hospitalized, and 18 cases have died. Compared to the same period in 2016, the number of hospitalizations has increased by 9.7%. However, the number of cases is still concentrated mainly in the Southern region (64.4%) and the Central region (19.9%) compared to the total number of cases in the country, because this is the area where the disease has been circulating for many years.

The Northern region has a lower incidence rate (12.4%), however, there has recently been an increase in the number of cases in Hanoi (the absolute number of cases in Hanoi ranks 3rd in the country, the number of cases per 100,000 people ranks 19th).

In response to the opinion that spraying chemicals to kill mosquitoes is not thorough, Associate Professor Phu said that mosquito-killing chemicals circulating on the market have all been licensed by the Ministry of Health. However, spraying chemicals requires cooperation and consensus from the people.

“For example, a 4-storey house, when spraying pesticides, you must spray all floors. Spraying pesticides only on the first floor is not effective because mosquitoes fly and move. Spraying pesticides also needs to be done in all houses in the same area. But the most basic measures are still to prevent mosquitoes from laying eggs and larvae to prevent dengue fever,” said Associate Professor Phu.

Therefore, every person and family needs to cover all water containers to prevent mosquitoes from laying eggs.

Weekly measures to kill mosquito larvae/wrigglers are taken by releasing fish into large water containers; washing medium and small water containers, turning over containers that do not contain water; changing the water in flower vases/vases; adding salt or oil to bowls of water placed under the cupboard. Eliminate waste materials and natural water holes that do not allow mosquitoes to lay eggs such as bottles, jars, broken glass, coconut shells, broken jars, old tires/vehicle tires, bamboo holes, leaf sheaths...

“If your house has a water tank on a high floor, check it because when the lid is flipped, it will be a nest for larvae and mosquito larvae because it is the favorite place for mosquitoes to lay eggs,” Associate Professor Phu advised.

Up to now, thanks to the drastic implementation of the mosquito larvae eradication campaign in all communes and wards, and proactive chemical spraying, over 96% of detected dengue fever outbreaks have been treated.

According to Dantri