Oropouche: South has unprecedented cases of mosquito-borne disease

Last week, Santa Catarina recorded the first cases of Oropouche fever in the state’s history. Three patients were diagnosed in Botuverá, in the Itajaí Valley. The disease is an arbovirus that presents symptoms similar to dengue and is considered endemic in Northern Brazil. The occurrence of cases for the first time in the territory of Santa Catarina draws attention due to its unprecedented nature and because it may be related to the impacts of climate change.

On her profile on In a sequence of publications, she points out the chances of the OROV virus, which causes the disease, reaching other continents and highlighted the importance of developing vaccines in this context.

“The loss of vegetation and destruction of ecosystems may be behind the increase in the incidence of this disease. Predictive models estimate that up to 5 million people are at risk of exposure to OROV in the Americas. ‘Considering the ‘global nature of environmental and climate change and the widespread migration of animals and humans, OROV will likely expand beyond South America in the near future’ (citing publication from the United States National Library of Medicine). Considering this scenario, the development of vaccines is of great relevance, but the reality is that it is a neglected disease and related to ecological and climatic imbalances, with risks of expansion and also risks of serious neurological complications”, he wrote in an excerpt of the sequence.

Fever is transmitted through the bite of a Culicoides paraensis, an insect also known as maruim, mangrove mosquito or sandfly. The disease virus has non-human primates, sloths, wild birds and rodents as its hosts in the wild cycle. In the urban cycle, human beings are the main ones affected.

Recommendations to prevent the circulation of the disease include keeping environments clean and preventing the creation of environments conducive to the proliferation of the mosquito vector. Different from Aedes aegyptiwhich transmits dengue, chikungunya and zika, the Culicoides paraensis It does not reproduce in still water, but in organic matter such as decaying leaves and fruits.

Endemic in the North

The first recorded cases of Oropouche in Brazil occurred in the 1960s. The disease is considered endemic in the North of the country, that is, it has a recurring incidence in this specific portion of the national territory. According to the weekly report released by the Ministry of Health last Thursday (25/4), Brazil has already had 3,862 cases of Oropouche fever this year. Most of the incidence is concentrated in Amazonas, which had 2,791 diagnoses. Altogether, the North Region concentrates almost 96% of Brazilian records.

According to the Ministry of Health, the number of registered cases has increased since last year. The rise coincides with the decentralization of diagnosis, carried out in molecular biology laboratories, now available in previously unaccessed regions.

Similarities with dengue

In addition to transmission occurring through a mosquito bite, Oropouche fever is similar to dengue fever due to its symptoms. People infected with OROV often experience headaches, muscle and joint pain, as well as nausea and diarrhea.

The Ministry of Health points out that, due to the similarities with dengue and even chikungunya, it is important that health surveillance and health care professionals pay special attention to differentiating the illnesses. The diagnosis is important to feed registration banks and guide vector prevention and control policies in specific areas.

Just like in cases of dengue fever, there is no specific treatment for Oropouche fever. In addition to seeking medical care, patients should rest and perform interventions to alleviate symptoms.