Brazil: Sao Paulo dengue cases top 500,000
The number of probable dengue fever cases in the Brazilian state of Sao Paulo has topped the 500,000 mark just a little more than 3 months into the year.
The Ministry of Health reports 521,878 probable dengue cases through April 5, including 385 deaths. An additional 473 deaths are still under investigation.
The case count in Sao Paulo accounts for 58 percent of the country total (896,680) and 72 percent of the total deaths nationally (536).
This puts the incidence rate at 1135.2 per 100,000 population, the highest in the country.
Dengue is part of a group of diseases called arboviruses, which are characterized by being caused by viruses transmitted by arthropod vectors. In Brazil, the vector of dengue is the female mosquito Aedes aegypti (meaning "hateful” and “from Egypt"). Dengue viruses (DENV) are scientifically classified in the Flaviviridae family and the Orthoflavivirus genus. To date, four serotypes are known – DENV-1, DENV-2, DENV-3 and DENV-4 –, which present distinct genetic materials (genotypes) and lineages.
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According to Brazilian officials, evidence suggests that the mosquito came on ships leaving Africa carrying slaves. In Brazil, the first clinically and laboratory-documented epidemic occurred in 1981-1982, in Boa Vista (RR), caused by serotypes 1 and 4. Four years later, in 1986, epidemics occurred in the state of Rio de Janeiro and some capitals in the Northeast region. Since then, dengue has been occurring continuously (endemic), interspersed with the occurrence of epidemics, generally associated with the introduction of new serotypes in areas that are not affected (without transmission) and/or changes in the predominant serotype, accompanying the expansion of the vector mosquito.
Aspects such as urbanization, disorderly population growth, poor basic sanitation and climatic factors maintain favorable conditions for the presence of the vector, with repercussions on the transmission dynamics of these arboviruses. Dengue has a seasonal pattern, with an increase in the number of cases and the risk of epidemics, mainly between the months of October of one year and May of the following year.
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Dengue fever is an acute, systemic, dynamic, debilitating and self-limiting febrile disease. Most patients recover, but some may progress to severe forms, even death. Almost all deaths from dengue fever are preventable and depend, in most cases, on the quality of care provided and the organization of the health service network.
Any individual who presents a sudden onset of fever (39°C to 40°C) and presents at least two of the following symptoms - headache, prostration, muscle and/or joint pain and pain behind the eyes - should immediately seek medical attention in order to obtain timely treatment.
There is no need to perform specific tests for the treatment of the disease, since it is based on the clinical manifestations presented. However, to support the clinical diagnosis, there are laboratory techniques available for identifying the virus ( up to the 5th day of onset of the disease ) and antibody testing ( from the 6th day of onset of the disease ).
Prevention
On December 21, 2023, the dengue vaccine was incorporated into the Unified Health System (SUS) . The inclusion of the dengue vaccine is an important tool in the SUS so that dengue is classified as another vaccine-preventable disease. Brazil is the first country in the world to offer the vaccine in its public health system.
In addition to the dengue vaccine, other actions the public can take is to prevent mosquito bites by using insect repellent, using window screens, wear loose-fitting, long-sleeved shirts and pants and taking steps to control mosquitoes in and around your home (Removal of containers in homes that could become breeding grounds for mosquitoes; Sealing of reservoirs and water tanks; Unblocking gutters, slabs and drains).