how to recognize the infection and what to do to avoid it

After the outbreak in Latin Americaespecially focused on the regions of Argentina and Brazilthe new threat of dengue comes to the old continent. On the other side of the Atlantic, cases have doubled the figure for 2023 and have left more than 9.3 million infected so far this year. And the number of deceased confirm the severity: 4,516 compared to 2,418, according to reports from the Health Information Platform of the Americas (PLISA)

In Europe, the European Center for Disease Prevention and Control (ECDC) has issued an alert as the trend is also upward. In In 2023, 130 cases of indigenous dengue were recordeddetected in patients with no travel history compared to 71 infections in the previous year, according to the latest newsletter.

But the truth is that beyond a localist x-ray, it is a growing global threat. According to data from the World Health Organization (WHO), between 2000 and 2019 the number of cases reported worldwide multiplied by 10going from 500,000 to 5.2 million and covering 129 countries.

Thus, last year was an important turning point worldwide. In 2023 the disease starred in a new rebound, characterized by the simultaneity of multiple outbreaks and geographic diversity. The numbers of affected people approached historical highs: more than five million cases and more than 5,000 deaths.

Why is there an alarm about dengue in Europe?

The concern is because we are facing a significant increase compared to the period 2010-2021in which the total number of locally acquired cases was 73. In addition, of the autochthonous infectionswhich denotes that the virus moves among the mosquitoes present on the continent, they focus on the imported cases. Their number has also grown: 1,572 cases reported in 2022 and more than 4,900 in 2023.

Its about largest number of imported cases of dengue reported since the start of surveillance at EU level in 2008. In the first months of 2024, several countries have reported substantial increases in the number of imported dengue cases, leading to ECDC to unflattering forecasts.

How is dengue transmited?

It is an infection that is transmitted by bite from a mosquito infected with one of the four serotypes of the dengue virus (DENV-1, DENV-2, DENV-3 and DEN-V 4). The culprits are Aedes albopictus and he Aedes aegypti.

What are the mosquitoes responsible for dengue in Europe?

Starting in 2024, in the continental region, the Aedes albopictus It is established in Austria, Bulgaria, Croatia, France, Germany, Greece, Hungary, Italy, Malta, Portugal, Romania, Slovenia and Spain, and is introduced in Belgium and Cyprus, as well as the Czech Republic, Liechtenstein, the Netherlands, Slovakia and Sweden.

There is also the Aedes aegypti, established in Cyprus and in several outermost regions of the EU, such as Madeira (Portugal) and the French Caribbean islands.

From 2010when the first recent dengue outbreak was recorded, there have been 48 vector-borne dengue outbreaks. Between 2010 and 2017, there were up to 3 outbreaks per year, 5 outbreaks in 2018, 7 in 2020, 10 outbreaks in 2022 and the peak was observed last year in 2023, with 8 outbreaks in France, 4 in Italy and 2 in Spain.

Symptoms What happens when you have dengue?

Beyond the stingthe manifestation of the infection comes with the fever. It normally affects infants, children and adults (especially the elderly and fragile).

The infection can be asymptomatic, between 40 and 80% of the cases there are no signs, or present with symptoms. If you have any suspicion, it is recommended to go to the doctor.

• Feverwhich can be moderate to highly disabling.
• Nauseadizziness and vomiting.
• Headachesintense headaches, pain behind the eyes may occur
• You can also experience muscle pains and in the joints.
• The appearance of skin rashes such as rashes It could be another sign. They may also appear petechiae.
• Only in 5% of casesthe disease can progress to a severe denguecharacterized by shock, difficulty breathing, severe bleeding, and/or severe organ complications.

Who should suspect having dengue?

Any person that live or have traveled in the last 14 days to areas with dengue transmissionAnd presents acute fever for 2 to 7 daysand two or more of the manifestations already mentioned.

Also considered a suspicious case is everything child who resides or has traveled in the last 14 days to an area with dengue transmission that presents acute febrile symptoms, generally lasting 2 to 7 days, with no apparent focus.

How long does dengue infection last and what is its treatment?

The duration depends on its impact and the symptoms that develop. There is no specific medicine. The symptoms are treated to alleviate the pathological process.

• The period of incubation ranges between 3-14 days and is prior to the appearance of symptoms.
• During the phase of manifest viremia or infectionsome 4-7 days (up to 12)the patient can transmit the infection to mosquitoes if bitten.
• The fever in dengue it can last 2 to 7 days and is usually accompanied by facial redness, erythema, generalized body pain, myalgia, arthralgia, headache, and pain behind the eyes.
• Depending on the evolution in those days towards more serious symptoms, it can be extended. more than 15 days with a recovery phase from another week.

How can you avoid dengue?

Prevention is based on vector control measures, This is against mosquitoes, so it is recommended personal protection against bites, and early identification and isolation of viremic or infected cases.

There is no specific treatment. There are two vaccines authorized in Spain, indications still pending.

When is dengue season?

As stated by the WHO, the disease follows a pattern consistent with the seasons: in the southern hemisphere occur in the first part of the yearand the cases in which northern hemisphere occur in the second half.

How many cases occur in Spain?

In 2023as stated in the Carlos III Health Institute (ISCIII), the 17 CCAA notified a total of 615 cases, of which 398 (64.7%) were confirmed. Was three indigenous casesall confirmed and notified by Catalonia, residents in the province of Barcelona. There were two women and one man, under 45 years old. Two of the cases required hospitalization and all had a good evolution with full recovery.

The Most of the cases reported in Spain are imported by travelers coming from countries with dengue transmission, according to the Carlos III Health Institute (ISCIII). In Spain, Ae. albopictus (popularly known as the tiger mosquito), is present and expanding, mainly along the entire Mediterranean coast, Andalusia, and some inland areas in Aragon, the Basque Country, Madrid and Extremadura. It is also established in the Balearic Islands.

The first cases of dengue due to indigenous vector transmission were identified in 2018 and there is a risk that more autochthonous cases will appear (people who have not traveled outside of Spain), especially during the periods of vector activity (April to November) in people who have traveled to areas where the tiger mosquito has established itself.

Why is there a rebound in these last two years?

Marta Diazcoordinator of the Imported Pathology and International Health Reference Unit of the La Paz-Carlos III University Hospital (Madrid)there is many factors that may be behind this explosion of cases. This expert commented to EL MUNDO a month ago “we must keep in mind that dengue transmission is cyclical and outbreaks of the disease usually occur in endemic areas every three to five years.

To this are added “phenomena such as climate change and global warming “They also seem to be giving wings to the virus, favoring the expansion of the vector that transmits the disease.”

According to the WHO, the fragility of saturated health systems after the COVID-19 pandemic must be remedied; the political and financial instability of countries facing complex humanitarian crises and high population movements. All of this forms a perfect cocktail that drives the spread of the disease and makes it difficult to control.