Question: who is at risk for contracting dengue fever? is there a certain age group or race that contracts dengue fever?

Reference:
 Dengue fever Dengue hemorrhagic fever Dengue shock syndrome Philippine hemorrhagic fever Dengue hemorrhagic fever Dengue shock syndrome Philippine hemorrhagic fever Thai hemorrhagic fever Singapore hemorrhagic fever Hemorrhagic dengue DF Dengue virus infection See More Summary The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 99828 Disease definition Dengue fever (DF), caused by dengue virus , is an arboviral disease characterized by an initial non-specific febrile illness that can sometimes progress to more severe forms manifesting capillary leakage and hemorrhage (dengue hemorrhagic fever, or DHF) and shock (dengue shock syndrome , or DSS). Epidemiology DF is found in the tropics worldwide, especially in Southeast Asia, the Pacific region, and the Americas, with 40% of the global population at risk. An estimated 50 to 100 million cases of DF, 500,000 hospitalizations, and 20,000 deaths occur yearly worldwide. Clinical description The vast majority of dengue virus infections result in DF, which is characterized by sudden onset of fever, malaise, headache (classically retro-orbital), and myalgia/arthralgia, often followed soon after by a petechial rash, which may be pruritic. In most cases, symptoms will resolve within 7 days without further complications. However, in a small minority of patients, a brief period of deffervescence is followed by worsening abdominal symptoms (pain, nausea, vomiting, diarrhea), thrombocytopenia , hemorrhage (DHF: epistaxis, bleeding gums, gastrointestinal bleeding) and a capillary leak syndrome (DSS: hemoconcentration, hypoalbuminemia, pleural effusion, shock). DHF/DSS are seen most often in children under the age of 15 years. Risk is greater with secondary heterologous infection by one of the four dengue virus serotypes, but severe disease may be seen with first infections. Etiology Over 25 different viruses cause viral hemorrhagic fever. Dengue virus belongs to the Flaviviridae family, genus Flavivirus. Four distinct serotypes, with significant strain variation, are recognized. Dengue viruses are maintained in humans and transmitted between them by the bite of infected mosquitoes, most commonly Aedes aegypti but also Aedes albopictus). Person-to-person transmission has not been reported. Diagnostic methods Common diagnostic modalities include serologic testing by enzyme linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR). Virus isolation may also be performed in specialized laboratories. The viremic phase of DF/DHF is usually brief (first 3-5 days of illness), after which time detection of anti-dengue IgM antibodies , which appear as early as 2-4 days after disease onset, is the mainstay. Numerous commercial ELISA assays are available with varying degrees of sensitivity and specificity. Differential diagnosis DF is difficult to distinguish from a host of other febrile illnesses such as malaria and typhoid fever (see these terms), especially early in the course of disease before the rash appears. For DHF/DSS, other viral hemorrhagic fevers, leptospirosis, rickettsial infection (see these terms) and meningococcemia need to be excluded. Management and treatment As there is presently no antiviral drug available for DF/DHF, treatment is supportive, following the guidelines for treatment of severe septicemia. Insecticide-treated bed nets, room screens and elimination of larval development sites should be used in open-air settings to prevent further transmission. Prognosis Case-fatality rates for DF are less than 1% but may rise to as high as 40% in DHF/DSS, largely dependent upon whether access to advanced medical care exists. Children and persons with underlying chronic diseases such as diabetes, heart disease, and asthma are at increased risk. The most severe phase of disease usually lasts only a few days and survivors generally have no lasting sequelae. Visit the Orphanet disease page for more resources. Symptoms This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom. Showing of Medical Terms Other Names Learn More: HPO ID 80%-99% of people have these symptoms Fever 0001945 Headache Headaches 0002315 30%-79% of people have these symptoms Abdominal pain Pain in stomach Stomach pain 0002027 Arthralgia Joint pain 0002829 Pruritus Itching Itchy skin Skin itching 0000989 Skin rash 0000988 5%-29% of people have these symptoms Ascites Accumulation of fluid in the abdomen 0001541 Bruising susceptibility Bruise easily Easy bruisability Easy bruising 0000978 Cardiorespiratory arrest 0006543 Cerebral hemorrhage Bleeding in brain 0001342 Diarrhea Watery stool 0002014 Epistaxis Bloody nose Frequent nosebleeds Nose bleeding Nosebleed 0000421 Gastrointestinal hemorrhage Gastrointestinal bleeding 0002239 Gingival bleeding Bleeding gums 0000225 Hepatomegaly Enlarged liver 0002240 Hypoproteinemia 0003075 Hypotension Low blood pressure 0002615 Lethargy 0001254 Leukopenia Decreased blood leukocyte number Low white blood cell count 0001882 Nausea and vomiting 0002017 Petechiae 0000967 Thrombocytopenia Low platelet count 0001873 Showing of 

Answer: 40% of the global population are at risk of dengue fever, which is found in the tropics worldwide, especially in Southeast Asia, the Pacific region, and the Americas, Of the  50 to 100 million cases of dengue fever that occur yearly, 500,000 lead to hospitalizations, and 20,000 to death worldwide. Dengue hemorrhagic fever and dengue shock syndrome occur most often in children under the age of 15 years.