Who is at risk for dengue?

Dengue fever has been known to be an illness that is commonly spotted in South-East Asia countries such as Malaysia, Singapore, Indonesia and Thailand. It is estimated that 100-400 million infections occur each year. A person with dengue can show a wide range of symptoms, at times even not with any prominent symptoms. 80% people with dengue infection are generally with mild infection and asymptomatic. Although the number may seem low for a person to catch severe dengue fever, it certainly is a life-threatening condition which can even result in death. Dengue prevention is important to reduce infections. Hence, who is at risk for dengue?
Before answering that, what is actually dengue? Dengue is a transmittable disease caused by the bites of the female mosquitoes coming from the Aedes species carrying the dengue virus, specifically the Aedes aegypti. Although we may have heard that the Aedes mosquito is responsible for dengue fever, the only way it becomes one is when the mosquitoes are infected by the dengue virus. This occurs when an uninfected mosquito bites a human with an already existing dengue virus circulating in the human body. Hence, mosquitoes are not the main culprit of dengue but only acts as a carrier or vector. It is still the dengue virus being the culprit for the array of symptoms.
There are several risk factors relating to dengue, causing a person to be susceptible to be infected with dengue. One of the most significant risks is the place itself. Living or travelling to regions or places that are known with dengue infection or an endemic place is one of the risks for dengue. Aside from regions in South-East Asia, this includes North-Eastern Australia, South America, Central America and Sub-Saharan Africa. With that in mind, the risk is higher when there is presence of stagnant water acting as the breeding medium for the Aedes mosquito acting as the vector to breed and live.
While people living or travelling to such regions and presence of stagnant water become a risk for the person to catch dengue, this does not necessarily mean a person is at risk for severe dengue. Risk factors of severe dengue include those with existing medical conditions such as asthma, obesity and hypertension. Risk for severe dengue increases when a person that has been infected by the dengue virus before, catches new infection. This is especially true when a person previously is exposed to the dengue virus serotype DENV-1 and then catches the serotype DENV-2 or DENV-3 or a person previously exposed to serotype DENV-3 and then catches the serotype DENV-2. It is said that the DENV-2 is considered to cause the most severe form of dengue.
Since symptoms of dengue vary, the ability to immediately spot one and to get immediate medical care can help to lower risk for complications caused by the dengue, especially the severe dengue. A person should be suspected with dengue when a person experience fever more than 40 C which lasts two to seven days and accompany with several symptoms such as muscle pain (myalgia), joint pain (arthralgia), vomiting, nausea, skin rash and headaches associated with pain behind the eyes (retro-orbital headaches). Such symptoms should already alert a person to get immediate medical care, especially when there are known cases of dengue fever occurring close to where they live. These dengue symptoms may seem to disappear during the critical phase of the disease but this is actually where dengue can result in life-threatening conditions. Thus, warning signs such as sudden abdominal pain, presence of blood in stool, vomiting blood, sudden bleeding nose or gums, breathing difficulty, fatigue or restlessness should be signs that the person needs to be brought to the emergency room promptly.