SAO PAULO – Brazil is working against the clock to stop the spread of the mosquitoes that carry dengue, as the number of cases of the disease nears 1.5 million, the highest number in four years.
Although dengue, a serious viral disease transmitted by the Aedes aegypti mosquito, is endemic in the South American country and the number of cases spikes every two or three years, the medical community is concerned about the rise in patients ahead of the rainy season, with some doctors speaking of a new epidemic.
At least 591 people, according to Health Ministry figures, died from dengue between Dec. 30, 2018, and Aug. 24 of this year, while health officials are investigating 486 other deaths possibly caused by the disease, which is characterized by high fever, intense headaches, muscle pain, gastro-intestinal problems and rashes.
As of Aug. 31, 1.4 million dengue cases had been reported across Brazil, a nearly 600 percent increase compared to the same period in 2018, when 205,791 cases were registered.
Brazil is on track to have the highest number of dengue cases since 2015, when 1.6 million cases of the viral illness were reported.
The big concern for health specialists is that the Southern Hemisphere summer, the time of year when dengue cases rise, has still not started.
“The rainy season has still not arrived, when the cases soar. We’re in the winter and, actually, a pretty dry one. We should not have had this spike, these figures are off the charts,” Dr. Thiago Henrique dos Santos, a public health specialist, said.
As a result, health officials are working to prevent an epidemic that could break out once summer arrives with high temperatures and rains.
State and local governments are conducting inspections of dwellings to eliminate the breeding sites of the Aedes aegypti mosquito and educating families on measures to take to prevent the spread of the disease.
Environmental monitoring officials, meanwhile, are focusing on automotive repair shops, construction materials dumps and cemeteries, all places where water can pool and provide a breeding site for the mosquitoes.
There are four varieties of the dengue virus, but people only develop an immunity to the type they previously contracted.
“When you are infected by one of the viruses, you are temporarily protected against the other three. During that time, people don’t get infected, but after a number of years, they are once again vulnerable,” said Dr. Alexander Precioso, a physician and scientist at the Butantan Institute.
The two specialists said that fighting the Aedes aegypti mosquito effectively would require a collective effort by authorities and the public.
“The fight against dengue is an eternal battle that depends on public policy, government action and also on the participation of citizens,” Precioso said.
Santos, for his part, said that “in recent years, the health sector has lost much money in the budget that was dedicated to environmental health policy.”
House-by-house inspections and training for professionals continue to be the most effective ways of fighting the Aedes aegypti mosquito, which needs water to breed, and stop the dengue’s spread in urban areas.
“The period for the larva to become a mosquito is just one week. It’s a very rapid cycle, very constant and when people forget and leave containers of water out, the dengue cases once again soar,” Sao Paulo environmental monitoring officer Dulcineia Prates told EFE.
To be considered an epidemic, dengue has to exceed 300 cases per 100,000 inhabitants and Brazil currently has a rate of 690.4 cases per 100,000 inhabitants.
In Sao Paulo, one of the states most affected by dengue, the incidence of the disease has reached 959.7 cases per 100,000 inhabitants and in the city of Sao Paulo, Brazil’s most populous urban area with nearly 12 million residents, the incidence of dengue is at 138 cases per 100,000 inhabitants, official figures show.