World Cup 2014: Brazil 'must act to prevent outbreak of dengue fever' during summer tournament, warns expert

Stadiums like Estadio das Dunas, in Natal, are being inspected for mosquito-breeding areas (Getty)

Picture the scene. It’s an hour before kick-off on Brazil’s north-east coast and anticipation is building on the streets of Natal. A crowd of football fans from every corner of the globe is gathering in cafés and caipirinha bars, all on their way to the gleaming new Estadio das Dunas – where health officials wearing gas masks are assiduously fogging mosquitoes out of the gutters, their fumes glimmering in the sun.

Most World Cups have their peculiar, defining feature – “Nessun dorma” at Italia 1990; vuvuzelas in South Africa 2010. But what are the chances that Brazil 2014 will be remembered – somewhat less fondly – as the dengue fever World Cup? Dengue, an infection spread by mosquitoes, “could be a significant problem” in some of the host cities, a leading British expert has warned, amid growing evidence that the disease is “on the march” around the world.

Brazil saw well over a million cases last year and the global tally now totals, by some estimates, around 400 million annually. The disease causes severe headaches and aching in the bones and joints, which can get so bad it has earned the sobriquet “breakbone fever”. Around a quarter of victims become very unwell and in a small proportion of cases it can be fatal.

Although the World Cup is being held at a time of year when the dengue risk is low for most parts of Brazil, for three host cities in the north east – Fortaleza, Salvador and Natal – it will be close to its peak, said Professor Simon Hay, an epidemiologist at the University of Oxford, who raised the alarm in the journal Nature at the end of last year.

“Dengue is on the march,” he told The Independent. “People tend to know about malaria – most people know that if you go to a tropical country you should take malaria pills. I don’t think most people know about dengue. It’s a horrible disease if you get it.”

The mosquito species which spreads dengue, Aedes aegypti, is easily identifiable by its white spots. It is a prodigiously successful breeder and thrives in urban areas, where it can breed in stagnant water – anything from a discarded coke can gathering rainwater to a blocked gutter. Clearing potential breeding sites in host cities will be crucial, Professor Hay said, adding that fogging – the use of aerosol insecticides – should begin in April and May.

His piece in Nature received some “pretty pointed comments” from Brazilians, he says. The authorities are understandably eager to allay fears of a major dengue outbreak, with international enthusiasm for the World Cup already dented by the deaths of workers building stadiums and riots over the cost of the event to a population still blighted by poverty.

But Professor Hay has no criticism for the Brazilian health authorities – merely a concern that many of the 500,000 international football fans expected to descend on Brazil this summer, largely from countries where dengue is unheard of, might not be as wary of the disease as they should be.

A Ministry of Health worker fumigates a public university which has suffered a dangerous outbreak of dengue fever (Getty)

“You’ve got lots of people coming and you pretty much know where they’re going and at what times. I think getting the word out that dengue is an issue – posters in the right place when fans are going into stadiums, will be important,” he said.

There are no drugs and no vaccines against dengue – although the latter is at the human testing stage at Brazil’s own Butantan Institute in Sao Paulo. The most effective way to prevent it is to avoid getting bitten.

Health authorities in Brazil say they are alive to the threat. Local areas were given a total of $363m (£218m) in 2013 to combat dengue and regional authorities are being tasked with inspecting stadiums and other areas where World Cup crowds will be congregating for mosquito breeding areas.