Once near to being eliminated in many parts of the world, dengue fever is making a deadly comeback. Experts say only a sustained and vigorous effort will put an end to this preventable disease.
When it comes to saving lives from infectious disease, knowledge is often the best antidote. Alejandra Mendoza-Rivera, who lives in Leon, near Nicaragua’s Pacific coast, knows this first hand. She credits the information about dengue fever brought to her by Nicaraguan Red Cross volunteers for saving the lives of her two children, Osmari, 2, and 12-year-old Francisco.
“Both children had high fever so we went to the health centre because…I was scared that it could be dengue,” she says. “They gave me the order for the exams and confirmed it.”
Thanks to the Red Cross visit, Mendoza-Rivera says she also takes even more care in cleaning her home. “I put into practice everything I learned during the presentations,” she says. “For example, keeping the water receptacles protected, cleaning my yard, putting covers on barrels, being careful and always clean.”
A mosquito-borne viral infection, dengue causes a flu-like illness and can occasionally develop into the life-threatening severe dengue. About 2.5 per cent of people who contract dengue die. Without proper preventive health and care services, fatality rates can exceed 20 per cent.
The outbreak in Nicaragua in 2013 had already claimed 14 lives by June, with 57 additional severe cases and 4,000 people affected by the dengue virus in what authorities confirmed as a 300 per cent increase in dengue cases over the prior year.
“Now that the Red Cross volunteers have come to help us two days a week, we have been able to fumigate and remove rubbish more often, and in this way were able to eliminate the Aedes aegypti mosquito — responsible for dengue transmission — during its aquatic phase,” says Silvio Pirado, a technician specializing in vector- and rodent-borne diseases at the Malpaisillo Health Centre in Leon.
Dengue and severe dengue affects most tropical and sub-tropical countries in the Asia-Pacific region, the Americas, Africa and the eastern Mediterranean. Over the past 50 years, dengue has spread from nine countries to more than 100 nations, making it the most rapidly-spreading vector-borne disease.
A preventable disease
But it shouldn’t have to be that way. “During the 1950s and 1960s, the Pan-American Health Organization adopted a public health strategy to fight dengue, which successfully reduced, and in certain cases eliminated, the disease in the Americas,” explains IFRC Under Secretary General Walter Cotte.
With time this momentum was lost. Dengue cases were once practically non-existent in countries like Brazil, Colombia and Mexico; today, these countries are counted among the top ten most endemic countries in the world.”
Today, almost half of the world’s population lives in dengue-endemic countries. The number of cases has risen from 15,000 per year in the 1960s to roughly 390 million today. Once seen as an urban and peri-urban disease, dengue is increasingly becoming a challenge in rural areas.
In Colombia, for example, the caseload has gone from 5.2 per 100,000 in the 1990s to 18.1 cases per 100,000 in the past five years. The increase in cases is a result of population growth, unplanned urbanization, lack of environmental sanitation, increased long-distance travel and ineffective mosquito control.
Insecurity, displacement and violence can also play a role. Nearly 80 per cent of the 30,000 residents of Guapi, in Colombia’s Cauca department, which suffered a dengue outbreak in 2013, have no access to safe drinking water. The municipality has no waste disposal or wastewater treatment plant so most waste is dumped directly into the river or the ocean.
Similarly, when Paraguay suffered its worst dengue outbreak in 2011, with a total of 38,206 confirmed cases and 62 reported deaths, the highest numbers of cases and fatalities hit both the relatively rural department of Alto Parana and the metropolitan area around the country’s capital, a sprawling urban zone encompassing ten cities and home to more than 2 million inhabitants.
The urban breeding ground
New communities on the city outskirts are overcrowded, lack solid waste management services and have inadequate water and sewer systems. Meanwhile, the dengue-carrying mosquito can breed anywhere from puddles on building sites, barrels of drinking water, stagnant drains to vases of flowers in peoples’ homes.
These are some of the reasons that National Societies, the IFRC and other organizations dealing with dengue say it’s time for a dramatic change in approach. Dengue eradication must shift from episodic, isolated dengue eradication campaigns to holistic, concerted and long-term efforts aimed at eliminating the conditions that nurture the disease.
Many Red Cross and Red Crescent efforts, for example, are funded through the Disaster Relief Emergency Fund (DREF), which allocates money quickly in response to emergencies such as outbreaks. These injections of money have made a significant impact in many countries in terms of reducing the outbreak’s damage, and they have had some long-term residual effects in helping National Societies to partner with other local and national organizations, set up depots with supplies and materials, and develop capacity and knowledge for ongoing interventions.
But they are not enough to keep the dengue effort going and therefore prevent the next round of outbreaks. What’s needed, health officials say, is long-term investment in integrated programming and community-level initiatives that lead to long-term behaviour change.
Much of this work is already being done by National Societies. It just needs to be scaled up. The Paraguayan Red Cross, for example, coordinates with the municipalities and health centres to eliminate mosquito breeding grounds and promote sanitation and case detection. It also supported preventive actions organized by the Ministry of Health and various city councils through community intervention and education. The National Society also carried out a dengue-awareness communication campaign using different mass media outlets.
Practice pays off
Similarly, in El Salvador, dengue prevention is part of an ongoing health programme funded by the Norwegian Red Cross that tackles preventive and environmental health at the community level. In conjunction with local family health units and other organizations, the National Society is involved in clean-up campaigns, water purification, fumigation and preventive health seminars. These go hand-in-hand with dental health services, sexual and reproductive health discussions and nutrition assessments, among other activities.
Prevention efforts also are often integral to the emergency response. In July 2014, for example, when Salvadorean authorities declared a yellow alert for another mosquito-borne disease called chikungunya, the IFRC’s US$ 184,000 DREF allocation supported National Society’s efforts to stop the immediate outbreak and prevent future epidemics of chikungunya and dengue.
In areas that have sustained prevention efforts, there is evidence that the investment of time and money pays off. In 2001, for example the Maldives saw a record 2,909 cases of dengue. Through its volunteering network, the Maldivian Red Crescent raised awareness in schools, carried out community clean-up activities and distributed information, education and communication materials. By 2013, the cases of dengue had decreased by 155 per cent in eight of the ten atolls where the National Society is operating.
By Gennike Mayers and Enrique Guevara
Gennike Mayers and Enrique Guevara are IFRC communications officers
based in the Americas.
Tatiana Marín from the Paraguayan Red Cross teaches Costa Rican school children how to prevent two mosquito-borne diseases, dengue and chikungunya, as part of the activities carried by the Costa Rican Red Cross in August 2014.
Photo: ©Vladimir Castro/IFRC
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