The global toll of dengue fever is becoming well known, with rising temperatures contributing to severe outbreaks that made 2019 the worst year on record for the disease.

In 1970 only nine countries faced severe dengue outbreaks. But the disease, which is spread by mosquitoes that can only survive in warm temperatures, is now seen in more than 100 countries. There are thought to be 390m infections each year

More than a million of those cases were in south-east Asia, hitting the poorest households hard and stretching health services.

The epidemic is exacerbated by poor infrastructure and lack of access to healthcare, with struggling health services overwhelmed by outbreaks.

Families at Angkor hospital for children in Siem Reap in north-west Cambodia

Dengue is episodic, but even accounting for natural dips and rises 2019 was deadly.

In the Philippines, there have been more than 1,000 deaths and 403,000 cases were reported this year – a 98% increase on 2018. In Thailand 110 people died from dengue between January and October, with 106,000 cases reported. For the same period last year there were just 50,000. From Bangladesh to Singapore, hospitals have struggled to cope with the unusually high number of patients.

If we didn’t have so many mosquito diseases to manage, we could invest more in intensive care and neonatal units Dr Ngoun Chanpheaktra

Since May the Angkor hospital for children in Siem Reap, north-west Cambodia, which treats more than 500 children a day free of charge, has launched several appeals for emergency donations.

“In peak season, we had seven times more cases of dengue fever than last year, and half of them needed to be hospitalised,” says Dr Ngoun Chanpheaktra, the director. “Between June and August, we had 200 cases a week and 30% to 50% of the beds were occupied by patients with dengue fever complications.

Patients who travel long distances to visit Angkor hospital are allowed to sleep on the premises.

“We have an annual budget of $6 million and as of 14 July, we had already spent $290,000 on mattresses, intravenous fluid bottles, dengue fever tests and staff overtime. If we didn’t have so many mosquito diseases to manage, we could invest more in chronic diseases, intensive care and neonatal units.”

In a rundown suburb of Siem Reap, three members of Piseth’s family contracted dengue this year. His 12-year-old son spent five days in the intensive care unit at Angkor hospital. In a desperate attempt to avoid medical fees Piseth, a tuk-tuk driver, first tried to treat his son at home.

Chan Pheakdey lies in bed at Angkor Hospital for Children

“When he started having a fever, we went to the first aid centre to buy bottles of intravenous fluid,” Piseth says. “We only earn $200 a month so we had to borrow $330 from a loan shark to pay for the cost of transport and IV bottles for the whole family. We didn’t go to the hospital right away, because we can’t lose days of work every time one of the children gets sick.”

Chan’s mother, sister and neighbours all caught dengue fever this year, putting a huge burden on the family. Their squalid living conditions are partly to blame – the land is flood prone, there’s a lack of sanitation and official neglect.

To save money, Chan Pheakdey’s family tried to treat him at home. The financial burden on a family can be crippling.

A few hours by plane west in the Thai town of Mae Sot, surrounded by mountains on the Thai-Myanmar border, François Nosten (above), director of the Shoklo Malaria Reasearch Unit, remembers even darker days. “When I arrived in Mae Sot in 1984, malaria was the leading cause of death,” he says. “Fifteen years ago, we still had 50 to 60 cases a day. Now it is one a year, thanks to an early detection campaign and a combined strategy of anti-malaria drugs and efficient community involvement. But there is no definitive global plan to eradicate dengue fever or similar diseases, particularly because the mortality rate is relatively low, so there is little incentive for pharmaceutical companies to invest in research.”

This year also saw a massive outbreak of chikungunya, another mosquito-borne disease, along the Thai-Myanmar border. The strain has never been recorded in Mae Sot before and is believed to have travelled north from the deep south of Thailand on the Malay border.

In Bangkok, Jaturang Wongjiragorn and his family live in a dilapidated shop-house on the edge of Chinatown and this year they felt the full force of a dengue outbreak in his neighbourhood. In September, his father went to hospital feeling sick. Following misdiagnoses at three different clinics and hospitals, which suspected flu or diabetes, he died five days later of organ failure brought on by severe dengue fever.

Bangkok Metropolitan Administration inspects and fumigates an area of Chinatown

After such fatal cases are reported, fumigation teams from the municipal authorities sweep in to spray affected neighbourhoods, but local authorities acknowledge that the efficiency of these short-term initiatives are limited as collective community responsibility breaks down in cities.

The search for a cure

From Bangkok laboratories to rural clinics along the Thai-Burmese border, there is great urgency to contain the disease.

At present, palliative care is the only certain treatment for dengue. Work is ongoing globally to create a reliable vaccine. A vaccine used in the Philippines was withdrawn and banned over concerns it might not be suitable for all children. The firm conceded that the product could put some children at higher risk if they had not previously had Dengue.



• Photographer Luke Duggleby and journalist Laure Siegel received agrant from the Earth Journalist Network/Internews to support the production of this story

• This article was amended on 3 January 2020 to remove a description of the parasite Plasmodium falciparum as a mosquito species.

• This article was amended on 8 January 2020 to clarify that a vaccine used in the Philippines was found to have put some children at risk if they had not previously had Dengue.



