Latin America faces unprecedented dengue outbreak

An outbreak of dengue fever has hit Brazil and several other Latin American countries and is expected to make 2024 the year with the highest number of cases and deaths in the region’s history. Extreme climatic phenomena, precarious socio-economic conditions and the abandonment of both preventive measures and the fight against the transmitting mosquito, Aedes aegypti, have contributed to its spreading to areas previously free of the virus, making dengue an increasingly urgent public health issue in the region and worldwide.

Patients in the Pediatrics ward at the Ceilândia Field Hospital, in the Federal District, on February 8, 2024 [Photo: Fabio Rodrigues-Pozzebom/Agência Brasil]

The latest report from the Pan American Health Organization (PAHO/WHO) on the epidemiological situation in the Americas cites dengue cases in 18 countries in the region, the most affected being Brazil, Argentina, Paraguay, Peru and Colombia. According to the report, the incidence of dengue increased by 249 percent compared to last year, and by 354 percent compared to the average of the last five years. This data, however, only covers the first eight epidemiological weeks, and the situation has only worsened since.

By mid-March of this year, the number of dengue cases in Paraguay was 23 times higher than in the same period last year, rising from 6,900 cases to 160,900. In the same comparison, Argentina saw a jump from 8,300 to 102,800 cases, and Peru from 16,900 to 46,500. In these countries, 43, 69, and 53 deaths have already been recorded this year, respectively.

Brazil, the primary source of infection, has registered more than 2 million probable cases on its own, and the Ministry of Health estimates that it will exceed 4.2 million by the end of the year, almost triple last year’s figure. As of March 23, 715 deaths had already been confirmed, and another 1,078 are under investigation.

Total number of suspected dengue cases as of the eighth Epidemiological Week in 2024 and 2023 and average of the last five years. Region of the Americas. [Photo: Graphic: WHO]

On March 13, the health minister of the government of Brazilian President Luiz Inácio Lula da Silva (Workers Party – PT), Nísia Trindade, downplayed the seriousness of the dengue epidemic in the country, writing in a social media post, “The lethality rate, at 0.3 percent of cases, is still less than half of last year (0.7 percent).” She added: “We are taking better care of the cases.”

In an interview with the daily Folha de São Paulo, epidemiologist Wanderson de Oliveira explained that several factors influence this apparently lower lethality rate: “Mild cases that may go unreported, difficulty in accessing treatment, and the quality of the health system can lead to a false impression that the disease is less serious than it really is.”

He continued: “At the moment, the priority should be to set up a task force to investigate the deaths and understand whether the causes of these deaths were due to the characteristics of the people or the quality of the services provided. This post [Trindade’s] was very unfortunate because it is cold and gives the impression that it is about numbers. For those who have lost a loved one, the lethality rate is 100 percent.”

The minister’s data for the comparison is still being analyzed. If the lethality rate for 2024 were calculated, including the deaths under investigation, the rate would be higher than in 2023.

The minister’s attempt to downplay an unprecedented outbreak of dengue fever  exposes not only the government’s “coldness” about the fatalities, but also its relation to the consequences of such a high incidence in the population and the suffering caused by the disease, which has been popularly called “bone-breaking fever,” due to the most well-known symptoms: severe headaches, backaches, along with muscle pain in the legs and joints.

When it progresses to a severe condition, dengue risks liver damage and bleeding. Another consequence that is still little known and, of course, never mentioned by government officials, are the neurological effects, which can manifest even in asymptomatic patients and appear long after infection.

In an interview with the podcast O Assunto, neurologist and scientist Marzia Puccioni said that between one percent and 20 percent of dengue patients can develop encephalitis, myelitis, meningitis, and even Guillain-Barré syndrome, an autoimmune disorder that attacks part of the nervous system.

Given the estimate of 4.2 million cases by the end of the year, 840,000 Brazilians could develop some neurological problem caused by the dengue virus. And there is no planning on the part of the health system to care for these future patients, quite the opposite.

The abandonment of the eradication policy 

The uncontrolled situation that is leading thousands of people to their deaths was not inevitable. It has been known for decades that dengue prevention and control depend on effective vector control measures.

The primary vector in the Americas is Aedes aegypti, a mosquito that lives in and near homes and breeds in any artificial or natural container holding standing water. The combination of high temperatures and rainfall favors an increase in the Aedes aegypti population. On this basis, representatives of the ruling class – including the WHO itself – have attributed the unprecedented rise in the disease to the El Niño phenomenon and global warming.

But none of this happened overnight. The climatic phenomena and the precarious conditions in which most of the region’s population lives favor the proliferation of the mosquito. They are as well known and predictable as they are ignored by the capitalist class. The truth is that the ruling class—similar to what we saw with the COVID-19 virus—abandoned any attempt to eradicate the dengue virus years ago.

Brazil itself once provided a historic example of eradication, a fundamental and long-standing principle used by medical science to combat countless infectious diseases.

Zoonosis team doing fieldwork to combat dengue outbreaks in neighborhoods of Osasco, in the metropolitan region of São Paulo, on 15/03/2024. [Photo: Paulo Pinto/Agência Brasil]

A campaign at the beginning of the 20th century against yellow fever, which is also transmitted by Aedes aegypti, allowed successive Brazilian governments to control the proliferation of the mosquito through massive action by sanitary agents. In 1954, when the vector eradication program was resumed, the Report of the National Yellow Fever Service referred to this work as “the most useful and revolutionary of the techniques ever introduced in anti-Aedes aegypti campaigns (...).”

By 1955, the mosquito had been eradicated in the country. This policy was accompanied by an effort by the Pan American Health Organization (PAHO/WHO) to eliminate it from other American countries, but the campaign did not come to an end. 

The reintroduction of Aedes egypti in Brazil and other countries in the region—this time bringing dengue and other arboviruses—coincided with the rise of US-backed military dictatorships in South America, which unleashed a massive attack on working class living standards and the region’s public health services.

Today, according to the WHO, the Region of the Americas accounts for 80 percent of dengue cases and has seen an increase in cases over the last four decades, rising from 1.5 million in the 1980s to 16.2 million in the 2010-2019 decade. The year 2023 broke the record with 4,565,911 cases, including 7,653 (0.17 percent) severe cases and 2,340 deaths (case fatality rate of 0.051 percent). In 2024, the scenario is already looking much more deadly.

Brazil, which a few decades ago could eradicate the vector, today registers cases of the disease in all of its 27 federal units, making its territory of eight million square kilometers the most extensive breeding ground for Aedes aegypti on the planet.

The capitalist system as an obstacle to universal healthcare

Some significant advances have been made in the last decade to combat dengue, such as the Wolbachia method, which consists of introducing mosquitoes carrying the Wolbachia bacteria into the environment, and the recently created QDenga vaccine. However, both are still in their initial application phase and have little production capacity. In addition, they are only effective in the long term, working in conjunction with the vector control actions that have been carried out for more than 70 years in Brazil.

However, after all this time, instead of increasing such action, what we have seen is a reduction over the last few years. Last year, President Lula sanctioned a spending ceiling that allowed for a reduction of almost 20 billion reais ($4 billion) in health funding.

According to the daily Metrópoles, the Federal District, the federal unit with the highest incidence today, has failed to invest R$241 million in the prevention of arboviruses over the last 10 years, losing 36.7 percent of the workforce responsible for combating mosquito outbreaks. A Federal Court of Auditors survey, published by TV Globo’s Profissão Repórter show, revealed that the proportion of health agents is only one for every 2,000 inhabitants. The Ministry of Health recommends six agents for every 2,000 inhabitants.

In the city of São Paulo, workers who combat dengue fever have just gone on strike, joining the unified movement of municipal workers that began on March 12. According to Sindsep (São Paulo Municipal Employees Union), 70 percent of the 28 Health Surveillance Units in the capital have joined the strike. On March 19, around 20,000 São Paulo public sector workers took part in an assembly that approved the continuation of the strike, whose main demand is a pay rise. The health workers also demand that at least twice as many staff be hired.

The strike by municipal workers in São Paulo must be defended as part of an international movement opposing the policy of mass death pursued by the capitalist class. The working class is the only force capable of defending the principle of universal healthcare, which has been abandoned by the ruling class for years.

In its New Year’s Statement, the World Socialist Web Site International Editorial Board stated:

The only way that the pandemic can be stopped is through a globally-coordinated elimination strategy, in which the entire world’s population acts in solidarity and with a collective determination to enforce a broad-based public health program.

The same can be said for dengue fever and countless other diseases neglected by capitalist governments around the world. “The subordination of public health spending to the insatiable profit interests of a money-mad financial oligarchy”, as the declaration stated, must be countered by “a world socialist revolution [to] end the pandemic” ensure public health and prevent the descent into capitalist barbarism and World War III.