THE ESSENTIAL
- The High Authority for Health (HAS) recommends vaccinating against dengue fever children and adolescents aged at least 6 years who have already had dengue fever and adults aged 17 to 60 years old with risk factors (sickle cell disease, complicated high blood pressure, diabetes, obesity, renal failure).
- For this, it recommends administering two doses of the live attenuated Qdenga vaccine, developed by the Takeda laboratory, spaced three months apart.
- At the same time, it is advisable to apply protective measures against mosquito bites (repellents, long clothing, mosquito nets, etc.).
Guyana, Martinique, Guadeloupe, Mayotte… Cases of dengue fever, a viral disease transmitted by female mosquitoes of the Aedes genus, continue to increase in these territories. This is why the High Authority of Health (HAS) defined a vaccination strategy against dengue which it presented in a press release published on December 17.
For this, the health authority took into consideration “the epidemiological indicators of dengue fever over the last 10 years in the overseas departments and regions, the burden of the disease in different population groups during the last epidemics in these territories, data from clinical trials concerning the effectiveness, immunogenicity, safety and tolerance of the live attenuated Qdenga vaccine developed by the Takeda laboratory, the first tolerance data from real-life use of the vaccine, the relevance of the test results serological tests carried out in the laboratory, evaluated with regard to the circulation of flaviviruses and the seroprevalence of dengue in these territories, the results of the public consultation.”
Two doses of Qdenga spaced 3 months apart to fight dengue fever
After these evaluations, the HAS recommends that certain categories of overseas populations be administered the Qdenga vaccine. The latter, which obtained a European marketing authorization (AMM) in December 2022 for the prevention of dengue fever in French people aged four and over, was evaluated by the High Authority of Health at the request of the Management General Health (DGS). The recommended vaccination schedule consists of two doses of vaccine spaced three months apart. At this time, the need for a booster dose has not yet been established. “The HAS recommends that the vaccination schedule be carried out during the inter-epidemic period. In the event of recent dengue infection, it is recommended to wait a period of 6 months before proceeding with the first injection of the Qdenga vaccine.”
Faced with previous cases of anaphylactic reactions after the administration of the Qdenga vaccine, the health authority recommends that doctors carrying out vaccination be prepared to deal with a possible anaphylactic reaction that may occur after the injection. “It is advisable to keep all vaccinated people under observation for at least 15 minutes after the injection. It is recalled that the Qdenga vaccine is contraindicated in immunocompromised subjects, pregnant women and breastfeeding women,” she indicates.
Dengue vaccine: who is affected?
Dengue vaccination is recommended for children and adolescents aged 6 to 16 years residing in overseas territories, including people suffering from sickle cell anemia or those with other comorbidities, “whose parents or legal guardians are able to produce documented proof of a previous dengue infection, that is to say biologically confirmed in the laboratory or clinically diagnosed in a dengue epidemic context and recorded in the dengue fever record health, for the child/adolescent to be vaccinated.” If no documented proof can be shown, a serological ELISA or EIA laboratory test is carried out beforehand in order to know the serological status of the child/adolescent.
Another category of overseas populations concerned: adults aged 17 to 60 years old with comorbidities (sickle cell disease, complicated arterial hypertension, diabetes, obesity, renal failure, chronic cardiopulmonary conditions, other hemoglobinopathies, thrombocytopathies), with or without a history of dengue fever. . After receiving the Qdenga vaccine, HAS reminds that these patients must continue to apply protective measures against mosquito bites, such as the use of mosquito nets, repellents or wearing long clothing. “Vector control remains an essential means of prevention in dengue control programs”, she added.