Dengue fever
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Dengue fever is a mosquito-borne disease caused by dengue virus, prevalent in tropical and subtropical areas. Asymptomatic infections are uncommon, mild cases happen frequently;<ref name="d865">Template:Cite journal</ref> if symptoms appear, they typically begin 3 to 14 days after infection. These may include a high fever, headache, vomiting, muscle and joint pains, and a characteristic skin itching and skin rash. Recovery generally takes two to seven days. In a small proportion of cases, the disease develops into severe dengue (previously known as dengue hemorrhagic fever or dengue shock syndrome)<ref>Template:Cite journal</ref> with bleeding, low levels of blood platelets, blood plasma leakage, and dangerously low blood pressure.<ref name="WHO2023">Template:Cite web</ref><ref name="BMJ2015">Template:Cite journal</ref>
Dengue virus has four confirmed serotypes; infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection with a different type increases the risk of severe complications, so-called Antibody-Dependent Enhancement (ADE).<ref name="CDC-Yello-2024">Template:Cite web</ref> The symptoms of dengue resemble many other diseases including malaria, influenza, and Zika.<ref>Template:Cite book</ref> Blood tests are available to confirm the diagnosis including detecting viral RNA, or antibodies to the virus.<ref name=":5">Template:Cite web</ref>
Treatment of dengue fever is symptomatic, as there is no specific treatment for dengue fever. In mild cases, treatment focuses on treating pain. Severe cases of dengue require hospitalisation; treatment of acute dengue is supportive and includes giving fluid either by mouth or intravenously.<ref name="WHO2023" /><ref name="BMJ2015" />
Dengue is spread by several species of female mosquitoes of the Aedes genus, principally Aedes aegypti.<ref name="WHO2023" /> Infection can be prevented by mosquito elimination and the prevention of bites.<ref name="www.unicef.org-2024">Template:Cite web</ref> Two types of dengue vaccine have been approved and are commercially available. Dengvaxia became available in 2016, but it is only recommended to prevent re-infection in individuals who have been previously infected.<ref name="WHO2018Vac">Template:Cite journal</ref> The second vaccine, Qdenga, became available in 2022 and is suitable for adults, adolescents and children from four years of age.<ref>Template:Cite web</ref>
The earliest descriptions of a dengue outbreak date from 1779; its viral cause and spread were understood by the early 20th century.<ref name="Henchal">Template:Cite journal</ref> Already endemic in more than one hundred countries, dengue is spreading from tropical and subtropical regions to the Iberian Peninsula and the southern states of the US, partly attributed to climate change.<ref name="WHO-Global-Situation-2024">Template:Cite web</ref><ref name="pmid38280388">Template:Cite journal</ref> It is classified as a neglected tropical disease.<ref>Template:Cite web</ref> During 2023, more than 5 million infections were reported, with more than 5,000 dengue-related deaths.<ref name="WHO-Global-Situation-2024" /> As most cases are asymptomatic or mild, the actual numbers of dengue cases and deaths are under-reported.<ref name="WHO-Global-Situation-2024" />
Signs and symptoms
[edit]Template:Multiple image Typically, people infected with dengue virus are asymptomatic or have only mild symptoms such as an uncomplicated fever (80%).<ref name=White10>Template:Cite journal</ref><ref name=Euro10>Template:Cite journal</ref> Others have more severe illness (5%), and in a small proportion it is life-threatening.<ref name=White10/><ref name=Euro10/> The incubation period (time between exposure and onset of symptoms) ranges from 3 to 14 days, but most often it is 4 to 7 days.<ref name=Gubler2010>Template:Cite book</ref>
The characteristic symptoms of mild dengue are sudden-onset fever, headache (typically located behind the eyes), muscle and joint pains, nausea, vomiting, swollen glands and a rash.<ref name="WHO2023" /><ref name="www.unicef.org-2024" /> If this progresses to severe dengue the symptoms are severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums or nose, fatigue, restlessness, blood in vomit or stool, extreme thirst, pale and cold skin, and feelings of weakness.<ref name="WHO2023" />
Clinical course
[edit]The course of infection is divided into three phases: febrile, critical, and recovery.<ref name="NEJM2012">Template:Cite journal</ref>
The febrile phase involves high fever (40 °C/104 °F), and is associated with generalized pain and a headache; this usually lasts two to seven days.<ref name="WHO2023" /><ref name="Chen">Template:Cite journal</ref> There may also be nausea, vomiting, a rash, and pains in the muscle and joints.<ref name="WHO2023" />
Most people recover within a week or so. In about 5% of cases, symptoms worsen and can become life-threatening. This is called severe dengue (formerly called dengue hemorrhagic fever or dengue shock syndrome).<ref name=NEJM2012/><ref name="Peads10">Template:Cite journal</ref> Severe dengue can lead to shock, internal bleeding, organ failure and even death.<ref name="Mayo-Clinic-Symptoms-2024">Template:Cite web</ref> Warning signs include severe stomach pain, vomiting, difficulty breathing, and blood in the nose, gums, vomit or stools.<ref name="Mayo-Clinic-Symptoms-2024" />
During this period, there is leakage of plasma from the blood vessels, together with a reduction in platelets.<ref name="Mayo-Clinic-Symptoms-2024" /> This may result in fluid accumulation in the chest and abdominal cavity as well as depletion of fluid from the circulation and decreased blood supply to vital organs.<ref name="Peads10" />
The recovery phase usually lasts two to three days.<ref name="Peads10" /> The improvement is often striking, and can be accompanied with severe itching and a slow heart rate.<ref name="Peads10" />
Complications and sequelae
[edit]Complications following severe dengue include fatigue, somnolence, headache, concentration impairment and memory impairment.<ref name="NEJM2012" /><ref>Template:Cite journal</ref> A pregnant woman who develops dengue is at higher risk of miscarriage, low birth weight, and premature birth.<ref>Template:Cite journal</ref>
Children and older individuals are at a risk of developing complications from dengue fever compared to other age groups; young children typically suffer from more intense symptoms. Concurrent infections with tropical diseases<ref>Template:Cite journal</ref> like the Zika virus can worsen symptoms and make recovery more challenging.<ref>Zanluca, C., & Duarte dos Santos, C. N. (2016). Zika virus – an overview. Microbes and Infection, 18(5), 295-301. Retrieved 27 September 2024</ref>
Cause
[edit]Virology
[edit]
Dengue virus (DENV) is an RNA virus of the family Flaviviridae; genus Flavivirus. Other members of the same genus include yellow fever virus, West Nile virus, and Zika virus. Dengue virus genome (genetic material) contains about 11,000 nucleotide bases, which code for the three structural protein molecules (C, prM and E) that form the virus particle and seven other protein molecules that are required for replication of the virus.<ref name=Life10>Template:Cite journal</ref><ref name=Guzman10>Template:Cite journal</ref> There are four confirmed strains of the virus, called serotypes, referred to as DENV-1, DENV-2, DENV-3 and DENV-4. The distinctions between the serotypes are based on their antigenicity.<ref>Template:Cite book</ref>
Transmission
[edit]
Dengue virus is most frequently transmitted by the bite of mosquitos in the Aedes genus, particularly A. aegypti.<ref>Template:Cite web</ref> They prefer to feed at dusk and dawn,<ref name="WHO2012">Template:Cite book</ref> but they may bite and thus spread infection at any time of day.<ref>Template:Cite web</ref> Other Aedes species that may transmit the disease include A. albopictus, A. polynesiensis and A. scutellaris. Humans are the primary host of the virus,<ref name="Gould">Template:Cite journal</ref> but it also circulates in nonhuman primates, and can infect other mammals.<ref>Template:Cite journal</ref><ref>Template:Cite web</ref> An infection can be acquired via a single bite.<ref name=Yellow10>Template:Cite web</ref>
For 2 to 10 days after becoming newly infected, a person's bloodstream will contain a high level of virus particles (the viremic period). A female mosquito that takes a blood meal from the infected host then propagates the virus in the cells lining its gut.<ref>Template:Cite book</ref> Over the next few days, the virus spreads to other tissues including the mosquito's salivary glands and is released into its saliva. Next time the mosquito feeds, the infectious saliva will be injected into the bloodstream of its victim, thus spreading the disease.<ref>Template:Cite web</ref> The virus seems to have no detrimental effect on the mosquito, which remains infected for life.<ref name="Gubler2010" />
Dengue can also be transmitted via infected blood products and through organ donation.<ref name="WHO2023" /> Vertical transmission (from mother to child) during pregnancy or at birth has been reported.<ref name="pmid20130380">Template:Cite journal</ref>
Risk factors
[edit]The principal risk for infection with dengue is the bite of an infected mosquito.<ref name="Bisen-2013">Template:Cite book</ref> This is more probable in areas where the disease is endemic, especially where there is high population density, poor sanitation, and standing water where mosquitoes can breed.<ref name="Bisen-2013" /> It can be mitigated by taking steps to avoid bites such as by wearing clothing that fully covers the skin, using mosquito netting while resting, and/or the application of insect repellent (DEET being the most effective).<ref name="Yellow10" />
Chronic diseases – such as asthma, sickle cell anemia, and diabetes mellitus – increase the risk of developing a severe form of the disease.<ref>Template:Cite web</ref> Other risk factors for severe disease include female sex and high body mass index.<ref name="NEJM2012" /><ref name="Guzman10" /> Infection with one serotype is thought to produce lifelong immunity to that type, but only short-term protection against the other three.<ref name="Chen" /> Subsequent re-infection with a different serotype increases the risk of severe complications due to a phenomenon known as antibody-dependent enhancement (ADE).<ref name="CDC-Yello-2024" /><ref name="pmid36996026">Template:Cite journal</ref>
The exact mechanism of ADE is not fully understood.<ref>Template:Cite journal</ref> It appears that ADE occurs when the antibodies generated during an immune response recognize and bind to a pathogen, but they fail to neutralize it. Instead, the antibody-virus complex has an enhanced ability to bind to the Fcγ receptors of the target immune cells, enabling the virus to infect the cell and reproduce itself.<ref name="pmid36996026" /><ref>Template:Cite web</ref>
Mechanism of infection
[edit]When a dengue virus carrying mosquito bites a person, the virus enters the skin together with the mosquito's saliva. The virus infects nearby skin cells called keratinocytes, as well as specialized immune cells located in the skin, called Langerhans cells.<ref>Template:Cite web</ref> The Langerhans cells migrate to the lymph nodes, where the infection spreads to white blood cells, and reproduces inside the cells while they move throughout the body.<ref name="Martina09" />
The white blood cells respond by producing several signaling proteins, such as cytokines and interferons, which are responsible for many of the symptoms, such as the fever, the flu-like symptoms, and the severe pains. In severe infection, the virus production inside the body is greatly increased, and many more organs (such as the liver and the bone marrow) can be affected. Fluid from the bloodstream leaks through the wall of small blood vessels into body cavities due to increased capillary permeability. As a result, blood volume decreases, and the blood pressure becomes so low that it cannot supply sufficient blood to vital organs. The spread of the virus to the bone marrow leads to reduced numbers of platelets, which are necessary for effective blood clotting; this increases the risk of bleeding, the other major complication of dengue fever.<ref name="Martina09">Template:Cite journal</ref>
Prevention
[edit]Vector control
[edit]
The principal risk for infection with dengue is the bite of an infected mosquito.<ref name="WHO2023" /> This is more probable in areas where the disease is endemic, especially where there is high population density, poor sanitation, and standing water where mosquitoes can breed.<ref name="Bisen-2013" /> It can be mitigated by taking steps to avoid bites such as by wearing clothing that fully covers the skin, using mosquito netting while resting, and/or the application of insect repellent (DEET being the most effective);<ref name="Yellow102">Template:Cite web</ref> it is also advisable to treat clothing, nets and tents with 0.5% permethrin.<ref name="CDC-2023">Template:Cite web</ref>
Protection of the home can be achieved with door and window screens, by using air conditioning, and by regularly emptying and cleaning all receptacles both indoors and outdoors which may accumulate water (such as buckets, planters, pools or trashcans).<ref name="CDC-2023" />
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The primary method of controlling A. aegypti is by eliminating its habitats. This is done by eliminating open sources of water, or if this is not possible, by adding insecticides or biological control agents to these areas. Generalized spraying with organophosphate or pyrethroid insecticides, while sometimes done, is not thought to be effective.<ref name="Euro102">Template:Cite journal</ref> Reducing open collections of water through environmental modification is the preferred method of control, given the concerns of negative health effects from insecticides and greater logistical difficulties with control agents. Ideally, mosquito control would be a community activity, e.g. when all members of a community clear blocked gutters and street drains and keep their yards free of containers with standing water.<ref name="www.nature.com-2024">Template:Cite web</ref> If residences have direct water connections this eliminates the need for wells or street pumps and water-carrying containers.<ref name="www.nature.com-2024" />
Vaccine
[edit]Template:MainAs of March 2024, there are two vaccines to protect against dengue infection; Dengvaxia and Qdenga.<ref name="www.ecdc.europa.eu-2023">Template:Cite web</ref>
Dengvaxia (formerly CYD-TDV) became available in 2015, and is approved for use in the US, EU and in some Asian and Latin American countries.<ref>Template:Cite web</ref> It is an attenuated virus, is suitable for individuals aged 6–45 years and protects against all four serotypes of dengue.<ref>Template:Cite web</ref> Due to safety concerns about antibody-dependent enhancement (ADE), it should only be given to individuals who have previously been infected with dengue, in order to protect them from reinfection.<ref>Template:Cite web</ref> It is given subcutaneously as three doses at six month intervals.<ref>Template:Cite web</ref>
Qdenga (formerly TAK-003) completed clinical trials in 2022 and was approved for use in the European Union in December 2022;<ref name="www.ecdc.europa.eu-2023" /> it has been approved by a number of other countries including Indonesia and Brazil, and has been recommended by the SAGE committee of the World Health Organization.<ref>Template:Cite web</ref> It is indicated for the prevention of dengue disease in individuals four years of age and older, and can be administered to people who have not been previously infected with dengue. It is a live attenuated vaccine containing the four serotypes of dengue virus, administered subcutaneously as two doses three months apart.<ref name="www.ecdc.europa.eu-2023" />
Severe disease
[edit]The World Health Organization's International Classification of Diseases divides dengue fever into two classes: uncomplicated and severe.<ref name="White10" /> Severe dengue is defined as that associated with severe bleeding, severe organ dysfunction, or severe plasma leakage.<ref>Template:Cite web</ref>
Severe dengue can develop suddenly, sometimes after a few days as the fever subsides.<ref name="Mayo-Clinic-Symptoms-2024" /> Leakage of plasma from the capillaries results in extreme low blood pressure and hypovolemic shock; Patients with severe plasma leakage may have fluid accumulation in the lungs or abdomen, insufficient protein in the blood, or thickening of the blood. Severe dengue is a medical emergency which can cause damage to organs, leading to multiple organ failure and death.<ref>Template:Cite web</ref>
Diagnosis
[edit]Mild cases of dengue fever can easily be confused with several common diseases including Influenza, measles, chikungunya, and zika.<ref name="WHO-2009">Template:Cite book</ref><ref name="MSD Manual Professional Edition">Template:Cite web</ref> Dengue, chikungunya and zika share the same mode of transmission (Aedes mosquitoes) and are often endemic in the same regions, so that it is possible to be infected simultaneously by more than one disease.<ref name="Beltran-Silva-2018" /> For travellers, dengue fever diagnosis should be considered in anyone who develops a fever within two weeks of being in the tropics or subtropics.<ref name="NEJM2012" />
Warning symptoms of severe dengue include abdominal pain, persistent vomiting, odema, bleeding, lethargy, and liver enlargement. Once again, these symptoms can be confused with other diseases such as malaria, gastroenteritis, leptospirosis, and typhus.<ref name="WHO-2009"/>
Blood tests can be used to confirm a diagnosis of dengue. During the first few days of infection, enzyme-linked immunosorbent assay (ELISA) can be used to detect the NS1 antigen; however this antigen is produced by all flaviviruses.<ref name="Beltran-Silva-2018">Template:Cite journal</ref><ref name=":5"/> Four or five days into the infection, it is possible to reliably detect anti-dengue IgM antibodies, but this does not determine the serotype.<ref name="Beltran-Silva-2018"/> Nucleic acid amplification tests provide the most reliable method of diagnosis.<ref name=":5" />
Treatment
[edit]As of July 2024, there is no specific antiviral treatment available for dengue fever.<ref name="Mayo Clinic-2022">Template:Cite web</ref>
Most cases of dengue fever have mild symptoms, and recovery takes place in a few days.<ref name="WHO2023" /> No treatment is required for these cases. Acetaminophen (Paracetamol, Tylenol) may be used to relieve mild fever or pain. Other common pain relievers, including aspirin, ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve) should be avoided as they can increase the risk of bleeding complications.<ref name="Mayo Clinic-2022" />
For moderate illness, those who can drink, are passing urine, have no warning signs and are otherwise reasonably healthy can be monitored carefully at home. Supportive care with analgesics, fluid replacement, and bed rest are recommended.<ref name="Scott Smith-2022">Template:Cite journal</ref><ref name="Peads10" />
Severe dengue is a life-threatening emergency, requiring hospitalization and potentially intensive care.<ref name="Mayo-Clinic-Symptoms-2024" /> Warning signs include dehydration, decreasing platelets and increasing hematocrit.<ref name="CDC-Case-Management">Template:Cite web</ref> Treatment modes include intravenous fluids, and transfusion with platelets or plasma.<ref name="Scott Smith-2022" />
Prognosis
[edit]Most people with dengue recover without any ongoing problems. The risk of death among those with severe dengue is 0.8–2.5%,<ref name=Kul2015>Template:Cite journal</ref> and with adequate treatment this is less than 1%. However, those who develop significantly low blood pressure may have a fatality rate of up to 26%.<ref name=Peads10/> The risk of death among children less than five years old is four times greater than among those over the age of 10.<ref name=Kul2015/> Elderly people are also at higher risk of a poor outcome.<ref name=Kul2015/>
Epidemiology
[edit]
As of March 2023, dengue is endemic in more than 100 countries with cases reported in every continent with the exception of Antarctica.<ref name="WHO2023" /><ref>Template:Cite web</ref> The Americas, Southeast Asia and the Western Pacific regions are the most seriously affected.<ref name="WHO2023" /><ref name=":2">Template:Cite web</ref> It is difficult to estimate the full extent of the disease, as many cases are mild and not correctly diagnosed. WHO currently estimates that 3.9 billion people are at risk of dengue infection.<ref name="WHO2023" /><ref name=":2" /> In 2013, it was estimated that 390 million dengue infections occur every year, with 500,000 of these developing severe symptoms and 25,000 deaths.<ref>Template:Cite journal</ref><ref name = "Jing_2019">Template:Cite journal</ref>
Template:External mediaGenerally, areas where dengue is endemic have only one serotype of the virus in circulation. The disease is said to be hyperendemic in areas where more than one serotype is circulating; this increases the risk of severe disease on a second or subsequent infection.<ref>Template:Cite web</ref>
Infections are most commonly acquired in urban environments where the virus is primarily transmitted by the mosquito species Aedes aegypti.<ref name="Gubler20102">Template:Cite book</ref> This species has adapted to the urban environment, is generally found close to human habitation, prefers humans as its host, and takes advantage of small bodies of standing water (such as tanks and buckets) in which to breed. In rural settings the virus is transmitted to humans by A. aegypti and other related mosquitoes such as Aedes albopictus.<ref name="Gubler20102" /> Both these species have expanding ranges.<ref name="NEJM2012" /> There are two subspecies of Aedes aegypti, where Aedes aegypti formosus can be found in natural habitats such as forests and Aedes aegypti aegypti has adapted to urban domestic habitats.<ref>Template:Cite web</ref>
Dengue has increased in incidence in recent decades, with WHO recording a ten fold increase between 2010 and 2019 (from 500,000 to 5 million recorded cases).<ref name="WHO2023" /> This increase is tied closely to the increasing range of Aedes mosquitoes, which is attributed to a combination of urbanization, population growth, and an increasingly warm climate.<ref name="White102">Template:Cite journal</ref><ref>Template:Cite web</ref> In endemic areas, dengue infections peak when rainfall is optimal for mosquito breeding.<ref>Template:Cite web</ref> In October 2023, the first confirmed symptomatic case of locally acquired dengue (i.e. not while travelling) in the US was identified in California.<ref>Template:Cite journal</ref>
The disease infects all races, sexes, and ages equally. In endemic areas, the infection is most commonly seen in children who then acquire a lifelong partial immunity.<ref name = "Jing_2019" />
History
[edit]The first historical record of a case of probable dengue fever is in a Chinese medical encyclopedia from the Jin dynasty (266–420) which referred to a "water poison" associated with flying insects.<ref name="Gubler982">Template:Cite journal</ref><ref name="EID062">Template:Cite journal</ref>
The principal mosquito vector of dengue, Aedes aegypti, spread out of Africa in the 15th to 19th centuries due to the slave trade and consequent expansion of international trading.<ref name="NEJM2012" /> There have been descriptions of epidemics of dengue-like illness in the 17th century, and it is likely that epidemics in Jakarta, Cairo, and Philadelphia during the 18th century were caused by dengue.<ref name="Gubler982"/><ref name=":0">Template:Cite journal</ref>
It is assumed that dengue was constantly present in many tropical urban centres throughout the 19th and early 20th centuries, even though significant outbreaks were infrequent.<ref name="Gubler982"/> The marked spread of dengue during and after the Second World War has been attributed partly to disruption caused by the war, and partly to subsequent urbanisation in south-east Asia.<ref name="Gubler982"/> As novel serotypes were introduced to regions already endemic with dengue, outbreaks of severe disease followed. The severe hemorrhagic form of the disease was first reported in the Philippines in 1953; by the 1970s, it had become recognised as a major cause of child mortality in Southeast Asia.<ref name="Gubler982"/>
In Central and South America, the Aedes mosquito had been eradicated in the 1950s; however the eradication program was discontinued in the 1970s and the disease re-established itself in the region during the 1980s, becoming hyperendemic and causing significant epidemics.<ref name="Gubler982"/>
Dengue has continued to increase in prevalence during the 21st century, as the mosquito vector continues to expand its range. This is attributed partly to continuing urbanisation, and partly to the impact of a warmer climate.<ref>Template:Cite web</ref>
Etymology
[edit]The name came into English in the early 19th century from West Indian Spanish, which borrowed it from the Kiswahili term dinga / denga, meaning "cramp-like seizure" – the full term of the condition being ki-dinga pepo: "a sort of cramp-like seizure (caused by) an evil spirit".<ref>Christie J. On Epidemics of Dengue Fever: Their Diffusion and Etiology. Glasgow Med J. 1881;16(3):161-176.</ref> The borrowed term changed to dengue in Spanish due to this word existing in Spanish with the meaning "fastidiousness" and this folk etymology referring to the dislike of movement by affected patients.<ref name="lexico-definition" /><ref name=EID06>Template:Cite journal</ref> Slaves in the West Indies having contracted dengue were said to have the posture and gait of a dandy, and the disease was known as "dandy fever".<ref>Template:Cite web</ref><ref name=Hal08>Template:Cite book</ref>
The term break-bone fever was applied by physician and United States Founding Father Benjamin Rush, in a 1789 report of the 1780 epidemic in Philadelphia, due to the associated muscle and joint pains. In the report title he uses the more formal term "bilious remitting fever".<ref name=Barrett09>Template:Cite book</ref> The term dengue fever came into general use only after 1828.<ref name=Hal08/> Other historical terms include "breakheart fever" and "la dengue".<ref name=Hal08/> Terms for severe disease include "infectious thrombocytopenic purpura" and "Philippine", "Thai", or "Singapore hemorrhagic fever".<ref name=Hal08/>
Research
[edit]Research directions include dengue pathogenesis (the process by which the disease develops in humans), as well as the biology, ecology and behaviour of the mosquito vector. Improved diagnostics would enable faster and more appropriate treatment.<ref>Template:Cite journal</ref> Attempts are ongoing to develop an antiviral medicine targeting the NS3 or NS5 proteins.<ref>Template:Cite journal</ref>
In addition to the two vaccines which are already available, several vaccine candidates are in development.<ref>Template:Cite journal</ref>
An area of active research is developing experimental models for Dengue, beyond experimental animal models. Organ Chips and Lab-on-Chips have been developed to model Dengue leak syndrome and mechanopathology.<ref>Template:Cite web</ref><ref>Template:Cite journal</ref>
Effects of climate change
[edit]Rising temperatures and altered rainfall patterns are expanding the season and habitats of Aedes mosquitoes, the primary vectors of the disease.<ref>Template:Cite web</ref> In India, a study has developed an early warning system that analyzes regional climate factors—such as temperature, rainfall, and humidity—to predict potential dengue outbreaks two months in advance, enhancing preparedness and response strategies.<ref name=":1">Template:Cite journal</ref><ref>Template:Cite web</ref> Future projections indicate that dengue transmission risk will continue to rise with the rise in temperatures.<ref name=":1" />
Society and culture
[edit]Blood donation
[edit]Outbreaks of dengue fever increase the need for blood products while decreasing the number of potential blood donors due to potential infection with the virus.<ref name=Teo2009>Template:Cite journal</ref> Someone who has a dengue infection is typically not allowed to donate blood for at least the next six months.<ref name=Teo2009/>
Public awareness
[edit]
International Anti-Dengue Day is observed every year on 15 June in a number of countries.<ref name=DayWHO2013>Template:Cite web</ref> The idea was first agreed upon in 2010 with the first event held in Jakarta, Indonesia, in 2011.<ref name=DayWHO2013/> Further events were held in 2012 in Yangon, Myanmar, and in 2013 in Vietnam.<ref name=DayWHO2013/> Goals are to increase public awareness about dengue, mobilize resources for its prevention and control and, to demonstrate the Southeast Asian region's commitment in tackling the disease.<ref>Template:Cite book</ref> Efforts are ongoing as of 2019 to make it a global event.<ref>Template:Cite web</ref>
The Philippines has an awareness month in June since 1998.<ref>Template:Cite news</ref><ref>Template:Cite news</ref>
A National Dengue Day is held in India annually on 16 May.<ref>Template:Cite web</ref>
Economic burden
[edit]A study estimated that the global burden of dengue in 2013 amounted to US$8.9 billion.<ref>Template:Cite journal</ref>
See also
[edit]References
[edit]External links
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