The disease is widespread in much of South America, and scientists say rising temperatures due to climate change are expanding the territory of the mosquitoes that carry dengue fever and increasing their reproduction.
In the first two months of this year, Paraguay registered nearly 100,000 suspected cases. This is more than five times his normal incidence. Peru has declared a state of emergency in large parts of the country as the virus continues to spread. In Argentina, the number of infected people is also increasing explosively.
But the disease is especially virulent and surging in Brazil, where epidemiologists say the number of dengue cases could reach millions, more than double previous records, and thousands of deaths. I predict that there will be.
Epidemiologists say the deepening public health crisis is a warning to the world. The fight against this disease has entered a new, unpredictable and dangerous phase. Dengue fever is now entering places it has never been seen before. And, as has been the case for a long time, the number of infections is surging to unseen heights.
This disease has historically been restricted to tropical climates. But in recent years, the number of infections has skyrocketed in many parts of the world (an eight-fold increase since the start of the 2000s), and the virus is increasingly spreading to areas that were once largely immune.
Community transmission is currently being reported in warm, rainy states in the United States, where the disease vector Aedes aegypti Mosquitoes are already roaming around. Florida reported a record 178 cases of community transmission last year. Local transmission has also been detected in California, Arizona, and Texas. A similar trend has been seen in southern Europe, where dozens of local infections were recorded last year.
Epidemiologists warn that this is likely just the beginning. In the coming years, due to climate change, A. Aedes aegypti Due to mosquito outbreaks, the disease is becoming increasingly prevalent in much of southern Europe and the southern United States, and may even become endemic.
“Dengue fever cases are increasing at an alarming rate,” said Gabriela Pas-Bailey, a dengue expert at the Centers for Disease Control and Prevention. “It's becoming a public health crisis, and it's happening in places where there hasn't been a crisis before.”
The risk in more affluent northern climates is reduced by several factors, including the prevalence of screen doors, air conditioning, and strong hygiene practices, which can reduce the number of pools of standing water. Aedes aegypti Can breed.
But epidemiologists say the threat should not be ignored, especially this year. More than 1 million dengue cases were registered in Brazil in January and February alone. By the end of the year, 4.2 million people are expected to be affected in the country, which is more than the number of infections recorded across the Americas last year during a record dengue outbreak.
“We don't have a large-scale outbreak in the United States, but that could change,” said Yale University epidemiologist Albert Coe. “We need to be concerned about a major outbreak in Brazil and other parts of South America, facilitating the spread of infection to other parts of the United States.”
Alarming rise in dengue fever
In recent years, cases of dengue fever in Brazil have steadily increased. That number jumped from a few hundred thousand a year in the early 80s to more than 1.4 million in 2013, and again last year to nearly 1.7 million. But this year, multiple forces have come together to create an unprecedented pandemic.
Extraordinary heat waves collided with El Niño, which often coincided with the widespread spread of dengue fever, leading to a more widespread spread of dengue fever. Aedes aegypti Extends the lifespan of mosquitoes.
“It's not just about their large numbers, it's about their longevity,” said Kleber Luz, who coordinates dengue research at the Brazilian Epidemiology Society. “Even for a day or two, it will have an impact on the number of dengue cases.”
Then came another accelerant. That is, all four types of dengue fever are prevalent at the same time. This reduced the immunological protection that people may have had in countries where dengue had been present for many years. “I've been studying dengue fever since 1997, and I've never seen a year where all four types were prevalent at the same time,” Luz said.
Felipe Naveca, an epidemiologist at the Oswaldo Cruz Foundation, a Brazilian scientific research institute, said that in moments like this, when multiple dengue variants are circulating, it is possible to become infected multiple times in a short period of time. He said it is particularly dangerous because of the Case numbers will likely remain high as each variant reaches its peak in succession.
“The scenario is not good,” he said.
Further complicating Brazil's fight against dengue fever are a number of chronic social diseases. Aedes aegypti Mosquitoes have long exploited inequality, poverty, chaotic urban planning, and frequently dysfunctional public health systems.
Millions of Brazilians live in densely populated, irregular communities called favelas, or “frontiers,” often in areas beyond the reach of government services and basic public services. Because plumbing is unreliable, people often resort to storing water outdoors, creating a breeding ground for countless mosquitoes.
“When people don't use water for a week, mosquitoes breed in it,” said Raman Velayudhan, a dengue expert at the World Health Organization. “This is an urban disease.”
Many of these factions are currently in conflict with certain factions in Brazil's Federal District, which by the end of last month had become the epicenter of the country's dengue outbreak.
“They didn't have their own bed.”
With invisible speed, the disease swept through the region's poorest areas, forming a ring around the wealthy center of Brasilia. By the end of February, the disease was spreading everywhere, with about 120,000 dengue cases in the city of 2.8 million people. The region's hospital system, which has withstood the onslaught of the coronavirus pandemic, is beginning to falter. Hospital beds were in short supply.
“The public and private healthcare systems of the federal district have now collapsed,” said Ibanéis Rocha, the district's governor. “It's serious now, but we haven't reached the peak of the epidemic yet.”
When Royde Rocha dos Santos, 57, was taken to a crowded hospital last month, the chaos was palpable, she said. Despite the severity of her symptoms, with dengue fever causing her platelet count to drop to dangerous levels, clinics in the Gama region could do little to treat her.
“I had to sit in a wheelchair for the first two days,” she said. “They didn't have their own bed.”
She was one of the lucky ones. She said there were patients around her and she was sitting on the floor receiving her IV. Others were angry and yelling at the lack of care, according to a video recorded by her daughter. One man screamed for painkillers so he could go home and die.
“There was nowhere for any of us to go,” she said.
On the other side of the district, in the poorer part of Seilandia, another family was scouring the city for a hospital bed. Mariana Torres Lima, 5, clearly had dengue fever, and she had a high fever, vomiting, and severe pain. But when her family took her to Seilandia Regional Hospital, she was turned away.
There, the family headed to a field hospital built to treat dengue fever patients. After waiting seven hours, Mariana was admitted to the hospital. She slept curled up under a coarse woolen blanket on a military cot.
Outside, my aunt Bruna Lila was furious. “The government doesn't care about us,” she said. “The streets are littered with trash and schools are not being cleaned. One thing leads to another.”
She sat down again. Around her, more and more people were arriving at the field hospital. By noon there were a few dozen people. Many people were falling down. Others were vomiting.
“This year is different,” said Antonia Natane López de Lima, 32, who attends to her sick son. “This year is worse than ever.”
