"I hallucinated that I was going to die," says Thinh Cuong Trinh. At just 13-years-old, Thinh has already been hospitalised twice by dengue.
He vividly recalls the crippling fever, loss of appetite, headaches and fatigue that have become a part of his childhood. It’s a disease which has drained his family emotionally.
In Thu Dau Mot, a small but thriving urban centre which skirts the Saigon River in Southern Vietnam, where Thinh lives, dengue has long cast a shadow over the proud local community spirit.
Home to 99 million people, Vietnam records around 110,000 dengue cases on average each year. In 2022, this figure has soared to almost 300,000 cases reported so far this year.
Almost half of all these dengue cases are recorded in Thinh’s home region. But hundreds of thousands more cases will go undetected.
Also known as “breakbone fever” because of the severe pain it can cause, dengue is the fastest-spreading tropical disease in the world. The viral infection is transmitted to humans through the bites of female Aedes mosquitoes, which thrive in tropical and subtropical urban areas.
Anyone can experience the more serious symptoms of dengue. But children, particularly those under the age of five, are at greater risk of severe dengue illness.
Thinh’s pain
“My child couldn’t walk, had a stomach ache, nosebleed, bleeding gums, and had to be hospitalised immediately,” says Thinh’s mother, Ngan Thi Ngoc Le, who has also suffered from dengue.
Ngan has had many sleepless nights caring for her sick children and visiting hospitals. “I worry about dengue outbreaks in the community as my family has dengue every year,” she says.
The second time her son was ill with dengue, she knew it was more severe.
“His condition was terrible, and the platelet level was very low. I was terrified and thought he was about to die. He screamed, cried, and turned off all the lights, as he only wanted to stay in the dark. He said he saw a ghost.”
Thinh survived. Despite struggling to walk at first and a slow recovery, he was able to return to his studies. “I just finished an exam (before) and then had to stay home for almost a month. When I was back in school, everything was new to me.”
Societal cost
His story is familiar across many parts of the world where young people with dengue are forced to miss classes. The Covid-19 pandemic has further added complexities to families living in dengue-affected areas, with the extra burden on the healthcare system making access to medicines even harder.
Nguyen Thi Thanh Nga, a community health promoter in the city, explains that the impact of dengue is felt by the whole family.
“In recent years, there have been many dengue fever outbreaks which have affected the health and wellbeing of the locals, mainly the children,” she says. “If a child is in hospital, the parents have to focus on taking care of them and their income is heavily impacted.”
Rising young case numbers
Just over an hour’s drive south, the country’s most populous city, Ho Chi Minh City, has seen an increasing number of young people with severe cases of dengue this year. Hospitals have reported children suffering from severe shock, liver damage, and others in need of dialysis.
“The rate of children getting severe dengue fever is higher than that of Covid-19 and the time from mild to severe is very quickly, requiring early detection,” Dr Truong Huu Khanh, vice president of the HCMC’s Union of Infectious Diseases, told Asia News Network in April.
Each year, the city’s Hospital for Tropical Diseases treats three to four thousand children for dengue. Up to five hundred of these patients will experience shock and require intensive care.
Dr Huynh Trung Trieu is the Deputy Head at the hospital’s Pediatric Intensive Care Unit (PICU) and has witnessed a sharp rise in children’s admissions.
“During the peak of dengue season, often from July to November, children’s hospitals in the city and PICU are overwhelmed,” Dr Trieu says.
“The issue of imbalance between resource availability and patients has never been solved. It is even worse following the Covid-19 pandemic.”
Dr Trieu explains that with four different serotypes of dengue virus, recovery from one doesn’t protect against an infection from another.
“Children in endemic areas can get dengue at a very early age and have little protection against other serotypes. With a second infection, they are more likely to develop severe dengue.”
Throughout the epicentre of the Covid-19 pandemic, PICU was turned into an intensive care unit, and only recently reopened to treat dengue patients.
“When a patient comes to PICU with shock, it’s hard to explain to the family immediately how severe they are and to predict the outcome,” Dr Trieu says.
“They are always very worried. We have to ask the parents to leave their child in intensive care and to wait outside the unit. They’re in tears and I have to ask them to trust me.
“Managing severe cases daily, facing the difference between survival and death, can be very tough.”
Dr Trieu’s patients receive a meticulously measured amount of fluid. Knowing when to give more, when to give less and when to stop is something of an art. The vast majority of cases will recover, but if the child has been admitted too late there can be significant organ damage and they could die.
“They don’t die immediately like with cardiac arrest. With dengue shock it doesn’t happen like that,” Dr Trieu explains.
“So we have to explain to the family gradually to try to help them accept the situation. They can’t accept that their child has died after just several days with a fever. It’s painful for the family and for the staff.
“Every death you remember forever. So the feeling of seeing a patient recover and be discharged is more valuable than anything for a doctor.”
Global Studies
Today, severe dengue affects most Asian and Latin American countries and has become a leading cause of hospitalisation and death among children in these regions. Studies in Asia and Latin America have shown that both the burden of dengue disease and the risk of severe clinical outcomes are higher in young children than in adults.
Among 132,000 children admitted to hospital with dengue in Ho Chi Minh City between 1996 and 2009, those aged 6-10 years had the highest risk of developing severe disease, but children under five years were significantly more likely to die from dengue. The same study found that girls had a much higher risk of severe dengue illness and death than boys.
Severe dengue is also seen in infants under one year of age in high transmission settings, with dengue antibodies acquired from the mother in utero hypothesised to be a predisposing risk factor for severe disease in this very young age group. Pregnant women who are infected with dengue can also pass the virus onto their foetus, and some studies have shown that women infected with dengue during pregnancy have an increased risk of adverse foetal outcomes such as low birth weight and premature birth
Dr Duong Le Quyen, an Epidemiologist and Vietnam Lead for the World Mosquito Program, also investigated dengue impacts in the southern coastal city of Nha Trang.
“My study during the period 2006 – 2016 observed a shift of peak dengue incidences toward younger age groups, with children under five experiencing comparable incidence rates to older children,” Dr Quyen says.
“The dengue data from the national surveillance in Vietnam between 2016 and 2020 showed that about 40% of the notified dengue cases in the country are children 15 years old and younger.
In Indonesia, a study in Yogyakarta city showed that 30% of two-year-old children had been exposed to dengue and 88% of 10-year-olds. It also found that half of all reported dengue cases between 2006-2016 were children aged 11 years and under.
Climate impact
In a recent major survey by international children’s charity, Save the Children, four out of five young people in 15 countries said they see climate change and economic inequality daily. Many linked extreme weather and increased incidence of disasters to health issues caused by heat exposure and a lack of access to water.
These changing weather patterns and extreme climate such as droughts, floods, heatwave, and rainfall are becoming more frequent and severe, providing favourable conditions for mosquitoes to breed in. Warming temperatures are expanding the geographies suitable for dengue transmission, and contributed to the global chikungunya and Zika epidemics during the past decade.
“When I was six months old, it rained heavily, and the water accumulated on rubbish and attracted mosquitoes,” says Oriana, 15, who fled violence in Venezuela with her family when she was a baby. One of more than 42,000 children and young people interviewed in the survey, Oriana now lives in Colombia.
“At that time, dengue was quite common. Many children died from the disease and I caught it and was close to death. I got dengue haemorrhagic fever from a mosquito bite and the doctor told my mum to say goodbye to me because there was nothing else they could do.”
As climate change lengthens the mosquito season and expands the range of the world’s deadliest creature to new regions, many more young people across the world will become vulnerable to mosquito-borne diseases. These impacts will be experienced disproportionately by countries and communities who are already at greater risk, are less likely to have access to quality healthcare — and are least responsible for the upstream causes of climate change.
The devastating floods in Pakistan triggered by heavy monsoon rains have caused increasing outbreaks of both water-borne and mosquito-borne diseases including dengue. The United Nations International Children's Emergency Fund (UNICEF) says more than 16 million children are affected by the floods and at risk of disease.
“The situation for Pakistani families is beyond bleak, and malnourished children are battling diarrhoea and malaria, dengue fever, and many are suffering from painful skin conditions,” says Unicef’s Pakistan representative, Abdullah Fadil. “Girls and boys in Pakistan are paying the price for a climate disaster not of their making.”
Hope for the future
With an additional one billion people projected to be at risk of dengue by 2080, scientists are seeking to strengthen surveillance capabilities and apply evidence-based and sustainable approaches to mosquito control and disease prevention.
In Thu Dau Mot, Thinh’s family is welcoming a new approach, Wolbachia — the World Mosquito Program’s groundbreaking solution to dengue. A symbiotic bacteria found in half of all insect species, Wolbachia blocks the transmission of viruses when introduced into Aedes aegypti mosquitoes.
Short-term releases of Wolbachia mosquitoes in dengue-affected communities allow Wolbachia to spread into the local mosquito population, effectively ‘immunising’ it against dengue and other viruses.
The self-sustaining, safe and cost-effective method has been deployed in 11 countries over the past decade, reaching more than 10 million people, and its effectiveness for dengue control has been demonstrated in multiple field trials.
“The dramatic increase of dengue cases over the past decade requires a sustainable and long-term prevention method,” says Dr Quyen. “We need to protect the children, the workforce, and the elderly of our communities in advance, rather than waiting until it’s too late.”
Since May 2022, releases have been taking place in the southern Vietnamese city. These concluded last month alongside others in My Tho.
Communities have embraced the solution, excited for a future where they don’t have to fear their children ending up in hospital. Many volunteered to host mosquito release containers (MRCs) and helped WMP staff find suitable and safe places for them.
“I think it has made a significant impact,” says Thinh’s mother, Ngan Thi Ngoc Le. “It will be wonderful if there is no dengue.