MSF tackles outbreak of dengue fever in Honduras with a new strategy

Due to an alarming increase in dengue fever cases in Honduras this year, MSF has launched an emergency intervention in Tegucigalpa, capital of the Central American country, Honduras, where the majority of cases have been reported. MSF is supporting local health services with a three-pronged approach focusing on medical care, vector control and community education. Such dengue intervention is relatively new for MSF.

More than 80 children have already been treated in an emergency paediatric ward set up by MSF. Mobile teams are also working with the local health authorities to identify and eliminate sources of infection in 4,000 households in the Tegucigalpa area.

Dengue, endemic in Central America, is a viral disease transmitted by mosquitoes of the genus Aedes. Symptoms are similar to flu, with headaches, fever, nausea, abdominal pain and rashes on the skin. Its most severe form, haemorrhagic dengue, causes bleeding and can lead to irreversible shock and subsequent death.

In Honduras, cases of the common form of dengue have significantly increased in 2010 compared to the previous year, with more than 50,000 cases already reported. However, the most alarming feature of this outbreak is the prevalence of haemorrhagic dengue, with more than 1,500 cases reported and 160 deaths - a massive 1,850 percent increase on 2009.

“I had come across the previous kind of dengue,” said Herminia Moncada, whose son was recently admitted to hospital with the disease. “But this is different. This dengue kills.”

The Ministry of Health has been responding to the high number of cases of dengue by making more hospital beds available and setting up specialised units in health centres in outlying areas. Despite this, the main referral hospital has still been overwhelmed by the upsurge in patients. Until recently, children with dengue fever had all been transferred to the referral hospital, as the decentralised units were only receiving adult patients.

To ease the overcrowding, MSF has set up an emergency ward at the San Felipe Hospital, on the outskirts of Tegucigalpa, where children under 15 with symptoms of the disease can be cared for. Already, on its second day of activity, the 23-bed ward was working to full capacity.

In hospital, treatment for children includes hydration and rest.

“With dengue, we are unable to identify beforehand the patients who will improve rapidly. There is no vaccine or specific medicine for the virus, so all we can do is to control the symptoms and treat the consequences while waiting for the body to stabilise,” said Dr Elisabeth Bragança, in charge of the MSF emergency ward.

Even if the treatment sounds simple, oral hydration involves certain complexities: serum needs to be administered carefully to avoid a fluid overdose, as dengue alters the permeability of blood vessels and there is a risk of fluids invading other parts of the body, causing complications such as pulmonary oedemas. “An ongoing balance in the amount of fluids given needs to be maintained,” said Dr Bragança.

MSF health staff are also spending time teaching the children’s parents and carers how to administer the fluid regularly to their children. “In my opinion, the success of this medical intervention mostly relies on us collaborating with the parents,” said Dr Bragança. Frequently, parents stay in the ward throughout the night, giving their children serum at set intervals and writing down the amounts so that they can tell the health staff later. Often the parents have no one to stand in for them and sometimes spend many days and nights without sleep. For this reason, emotional support for the parents is one element of the intervention.

For the MSF team, seeing the children start to recover can be a very rewarding experience. Just one day after being admitted to the ward, five-year-old Lucía Isammar Elvir was able to give her mother a big smile and say that she wanted to go home, saying, “I want to paint and draw”.

Education, ‘abate’ application and fumigation: core aspects in the fight against dengue

With dengue fever, medical treatment on its own is not enough, and must go hand in hand with educating people about how to prevent outbreaks from happening in the first place. “Education is an essential component of fighting dengue; it is a crucial aspect that will define the course of future epidemics,” said Luis Montiel, logistics coordinator for the project.

In addition to providing medical care, MSF is fighting the dengue outbreak with ‘vector control’. This means tackling the mosquitoes that spread the disease. Along with the Ministry of Health’s vector control body, MSF mobile teams are at work in the Manchen settlement, on the outskirts of Tegucigalpa, where the highest rates of affected people have been reported.

Mosquitoes carrying the dengue virus breed in stagnant water, so proper water management within households is vital. In the Manchen settlement, where the houses are on hillsides, families receive water only every fortnight, which they then store in tanks. In the narrow corridors of their houses, jerry cans and water containers provide a perfect environment for mosquitoes to breed, and so are a potential source of infection. If rubbish and rubble are allowed to accumulate, they too can provide a breeding ground for mosquitoes. Among these mostly poor families, waste management is no easy task. María Mercedes Suazo Bustillo, 89, explained how, ever since one of the rooms in her house had collapsed, she had been unable to get rid of the rubble and useless furniture. “I am poor, and to throw this away costs money, this is why I cannot do it.”

So as to raise awareness and educate people on how to keep stored water free from mosquito larvae and avoid rubbish accumulating, an MSF team is going from house to house through the neighbourhoods, looking for potential sources of infection and explaining how to stop mosquitoes breeding and spreading the virus. The challenge is to change people’s habits and social customs, and to involve them in the fight against dengue. “Bear in mind that the inspector does not come and stay with you,” says a member of the MSF team of educators through his loudspeaker.

The MSF teams going from house to house also apply ‘abate’: this process uses a chemical to treat any standing water and prevent mosquito larvae from hatching. Later on, once the team members have the trust of the families, they will return to fumigate the houses, with the aim of breaking the mosquitoes’ cycle of reproduction. So far, MSF has applied abate to 700 households and fumigated 400 houses, and plans to fumigate another 4,000 more.

Remaining vigilant about dengue

MSF is conducting an emergency response to a dengue outbreak in Tegucigalpa, the capital of Honduras. To find out more about what it involves, we spoke to Lucia Brum, MSF technical advisor for emerging diseases.

Does the increase in dengue fever outbreaks in Latin America mean there are insufficient resources to control the disease?

“The fight against dengue requires a comprehensive, inter-related strategy, which includes epidemiological and entomological surveillance, community education, environmental sanitation, vector control (ie controlling the mosquito that transmits the disease) and medical treatment. So the problem is not a lack of economic resources per se, but the absence of a comprehensive approach to the disease by public health programmes in most Latin American countries. The health programmes often lack continuity or fail to address all aspects of combating the disease.

“There are also socio-economic factors at play, including poor sanitation and problems with water supplies. For example, in the areas in Honduras where the MSF teams are working, residents only receive water once every two weeks, which means they have to store it. This increases the chances of dengue occurring, because the Aedes aegypti mosquito that passes on the disease breeds in stagnant water. When rubbish isn’t collected regularly, this can be a problem, too, since garbage can also harbour stagnant water.”

What should we do to fight dengue?
“Dengue needs to be fought on a daily basis – we must never lower our guard. Media attention tends to focus on major outbreaks of the disease, when there are large numbers of cases, but, as I mentioned earlier, there are a whole series of things we can do, all year round, first to prevent, and then to contain, the disease.

“There is a tendency to lower our guard because, unlike other diseases, which tend to be stable all year round, dengue occurs in epidemic peaks. These generally coincide with warmer weather and the rainy season, usually during the second half of the year in Latin American countries.

“During an epidemic, there is a tendency for government officials and the population at large to blame each other for what is happening. But really dengue prevention is the responsibility of everyone. On one hand, it depends on the state promoting community education that will encourage people to learn what they can do to protect themselves. On the other hand, people need to develop their own active prevention strategies. Without community participation, and as long as there is no effective vaccine, we will never be able to eradicate dengue.”

Can you stop the transmission of dengue, and is research being done to find a drug or vaccine to protect against it?
“Until now, the only way to prevent dengue has been through ‘vector control’, which means fighting the mosquito that transmits the disease. On a medical level, the majority of cases are treated syptomatically and as outpatients (without needing to take a patient into hospital). Medical staff can alleviate the symptoms and try to avoid complications, but there is no etiological treatment for dengue, and there are no antiviral drugs specific to the disease.

“The success of the treatment and a good prognosis are closely related to clinical assessment and keeping the patient well hydrated from early on. However, during dengue epidemics the high percentage of the population affected means that health services tend to become overcrowded, hindering the critical early clinical assessment. This then contributes to the development of severe cases (hemorragic dengue and dengue shock syndrome) and increasing mortality.

“Twenty-six years ago the World Health Organization formed a committee for the development of vaccines against dengue, with the aim of encouraging laboratories and research institutes to participate, but a vaccine is still not available on the market.

“This lack of a vaccine can be attributed to several factors, but the main problem is that there are four different types of dengue virus (serotypes 1, 2, 3 and 4), so that, to be effective, a vaccine must inhibit all four serotypes simultaneously.

“There is an urgent need for a vaccine because it is expected that dengue will spread to other countries and epidemics will become even more numerous and severe. It is anticipated that a vaccine may become available in the next five years.”

Why are there so many cases of dengue in Honduras at the moment?
“The global emergence of dengue as a major viral disease transmitted by mosquitoes is closely related to the problems of modern society in less developed countries: demographic explosion, unplanned urbanisation, the deterioration of public health programmes, and environmental pollution, with plastics and tyres serving as breeding grounds for mosquitoes. Globalisation has also played its part, with the transfer of patients, vectors and viral serotypes to areas where there were no previous cases of dengue. Similarily global warming has also contributed to the spread of the disease.

“The situation in Honduras is part of a recent global trend: in Latin America, Asia, Africa and Oceania epidemics have been increasing, with more cases of classic dengue fever, but also increased incidence of severe cases, both hemorrhagic dengue and dengue shock syndrome. These last two are the most dreaded forms of the disease, requiring hospital care as they are potentially life-threatening. Both are the focus of MSF’s medical intervention for children in the dengue paediatric ward of San Felipe Hospital in Tegucigalpa, as this is the age group that is most at risk, accounting for more than 70 percent of all reported deaths.”

What is the impact of outbreaks on affected countries?
“The main burden that dengue imposes on a country is the huge number of hospital admissions and the number of days that the illness lasts. The effective care of patients during epidemics is qualitatively different from that needed for individual attention. Caring for a large number of dengue patients requires equipment, trained doctors and nurses, fast criteria for risk classification of patients, beds and materials, and establishing treatment and isolation guidelines. Isolation refers not only to the usual precautions for handling blood and other bodily fluids, but also to the use of mosquito nets. If mosquitoes of the Aedes type are present in the hospital wards and bite patients with viremia (the virus circulating in the blood during the febrile period), then the insects can transmit the infection, contributing to the spread of the epidemic.

“The disease also generates indirect costs that are not usually taken into account but which have a substantial economic impact. There are the working days lost by the affected population: a patient needs an average of 10 days of rest before recovering [not for nothing is the disease known as the ‘bone-breaker fever’]. Epidemics also overwhelm hospitals, and health systems are overstretched, disrupting the management and flow of patients with other diseases.

“As I have said, it is vital to develop comprehensive strategies to combat the disease. With good guidance, access to health services and early clinical management, no one should die from dengue fever.”