Dengue has arrived in Spain. This emerging disease, native to tropical areas and which has experienced a rapid expansion across the globe in recent years, has already caused the first cases in our country. It is about two adult relatives who contracted the disease in August after spending a few days of vacation in municipalities of Murcia and Cádiz. The National Center of Microbiology has confirmed that both were infected by the dengue virus. The results of a third member of the family, a woman also adult, are pending confirmation after suffering "symptoms compatible with the disease," reported last night the Ministry of Health. Those affected, residents of the Community of Madrid and Murcia, are completely restored.
Dengue is a usually mild disease caused by a virus of the flavivirus genus for which there is no specific treatment or vaccine, so medical care is focused on alleviating the symptoms and giving life support in the most serious cases. It is not transmitted from person to person, but rather it is the mosquito that bites a person carrying the pathogen and transmits it to the next person, also stinging it. The vector that has probably transmitted the disease is the tiger mosquito (Aedes albopictus), widely spread on the Mediterranean coast and also present in communities such as Aragon and the Basque Country. The first detection of the virus in Spain was in 2004 in Sant Cugat del Vallès (Barcelona). His arrival in Europe took place a few years earlier on board of shipments of tires from Asia.
.@sanidadgob detects two cases of #dengue in people who had no history of having traveled to areas where this disease is endemic. They could be the first autochthonous cases of this disease, which is transmitted through the tiger mosquito (Aedes albopictus)
– Jessica Mouzo (@CinzasNoPeto) October 9, 2018
Although there are other mosquitoes that can also transmit the virus, there is no record of their presence in Spain despite the multiple controls on these insects carried out in all the autonomies. Aedes aegypti, for example, was detected on the island of Fuerteventura last December. It was the first time in decades that this mosquito – which can also transmit other viruses such as yellow fever and zika – was detected in Spain. The Canarian authorities, however, gave it to be eradicated only four months later.
400 million infected. A recent study by the World Health Organization (WHO) estimates that in recent years the incidence of the disease in the world has increased from 100 million cases annually to about 400 million. Of them, approximately a quarter (about 100 million a year) manifest symptoms of the disease, although mostly mild. Some 500,000 people eventually require hospital care. Mortality among this last group is close to 2.5%.
Four serotypes. There are four serotypes of the disease. To contract one of them immunizes for life against reinfection by that same serotype, but not against the other three. Moreover, if a person suffers two successive infections with two different serotypes, the chances of the patient developing the most severe form of the disease, hemorrhagic dengue, exponentially increase. The Ministry of Health has not yet reported the serotype detected in Spain.
Worldwide expansion. Until 1970, only nine countries in the world had suffered serious dengue epidemics. Now, the disease is endemic in more than 100 countries in the WHO regions of Africa, the Americas, the Eastern Mediterranean, Southeast Asia and the Western Pacific.
Arrival in Europe. France registered the first autochthonous case in 2010. It was a man who contracted the disease in Nice. Along with Italy, France is the country that has registered more cases of indigenous dengue in recent years, although the circulation of the virus has been sporadic and the majority of patients treated were infected in countries where the disease is endemic, as in Spain.
Other transmission routes. Dengue is transmitted almost in all cases by mosquito bites. However, the scientific literature contains some exceptional cases of
The arrival of dengue to Spain was expected by experts: "The virus is expanding around the world, there have been other cases in Europe and in Spain we have the mosquito that transmits it. It was only a matter of time, "says José Miguel Cisneros, president of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). Cisneros, however, qualifies epidemiologically as "very relevant" the confirmation of the first autochthonous cases. "We have a new infectious disease to cope with, although we have a health system that is well prepared for it, much more than in most of the countries where dengue has had an important impact on the health of the population," ensures
Health and the three communities involved – Madrid, Murcia and Andalusia – have launched a "coordinated response actions" system with four objectives. The first was "to investigate the detected cases and possible places of exposure" to the virus. The second, once located the place where the infection occurred, "the retrospective investigation to detect other possible cases." In these same zones, the communities will carry out a study to know the population of mosquitoes and "make recommendations" for their control. Finally, the actions of "communication and awareness to health professionals and laboratories for the early detection and notification" of cases will be reinforced.
Although Health does not rule out that new cases may be discovered, ministry sources are optimistic that with the arrival of cold and the interruption of the natural cycle of mosquitoes, "the probability of indigenous transmission at this time is very low." The initial symptoms of dengue, which can also occur asymptomatically, are similar to those of the flu: high fever and intense pain in the head, behind the eyeballs, muscles and joints. Sometimes it also produces a skin rash and vomiting. The greatest risk of the disease is suffering a more lethal complication: hemorrhagic dengue, which mainly affects children and vulnerable people. Symptoms appear between three and 14 days after the bite. WHO estimates that every year about 500,000 people require hospitalization for the virus. The mortality rate among this group is close to 2.5%, according to several medical studies.
Dengue is not unknown in Spanish hospitals. In recent years, the number of patients treated after traveling to countries where the disease is present has grown remarkably. In 2015, there were 168 people, a number that increased to 261 the following year, according to data provided by the Spanish authorities to the European Center for Disease Prevention and Control (ECDC, in its acronym in English).
In Europe, cases imported in 2016 amounted to 2,824 and France and Italy have registered sporadic autochthonous cases in recent years.
"Hospitals and health centers have experience in treating patients with the virus," says José Miguel Cisneros, who emphasizes that in recent years "much progress has been made in key tools to provide good care such as early diagnosis, which allows to confirm in a few hours the presence of the virus in the body. "