Obese children infected with dengue appear to be at higher risk of hospitalization

Very overweight children infected with dengue appear to be at higher risk of hospitalization, according to researchers who say more public awareness is needed about the risks of obesity and severe disease.

Spread by the Aedes mosquito, cases of dengue reached a historic high of over 6.5 million in 2023, with more than 7,300 dengue-related deaths reported, according to the World Health Organization. About 90 percent of those hospitalized are children less than five years old.

With 10 million cases already reported this year by the end of June, 2024 is set to break the record again.

Neelika Malavige, professor in Immunology and Molecular Medicine at the University of Sri Jayewardenepura, Sri Lanka says the disease is a significant problem in many South American and Asian countries including Sri Lanka.

“Some individuals develop [the severe form] dengue hemorrhagic fever, requiring hospitalization,” said Malavige, co-author of the study, published in PLOS Neglected Tropical Disease.

“Others develop plasma leakage, which leads to shock, and if untreated, death. Therefore, early detection of complications is crucial.”

Obesity and diabetes – on the rise in many countries – are known risk factors for dengue but there is little data on whether these conditions lead to more dengue-related hospitalizations, say the researchers.

To investigate this, they looked at almost 5,000 Sri Lankan children aged 10 to 18 years, analyzing their case details including hospitalizations due to dengue and body mass index (BMI).

Dengue-infected children with higher BMI for their age group – 50th to 85th centiles – were associated with higher hospitalization rates as compared to children with a lower BMI. Those in the top centiles (98th and above), indicating clinical obesity, were twice as likely to be hospitalized than the rest.

With the increase in obesity in many countries, it would be important to create awareness and educate the public of the potential risks regarding obesity and risk of severe disease and hospitalization from dengue.”

Neelika Malavige, Professor in Immunology and Molecular Medicine at the University of Sri Jayewardenepura, Sri Lanka

“It definitely is important to study if obesity, diabetes, and metabolic diseases lead to more symptomatic illness and also increase in hospitalizations,” she stressed.

Dengue is often referred to as break bone fever because of the severe joint, bone and muscle pain it causes. Transmission usually occurs during the rainy season when the temperature and humidity are conducive for build-up of the mosquito population.

According to the WHO, dengue is now endemic in more than 100 countries, with the Americas, South-East Asia, and Western Pacific regions the most seriously affected.

Marianne Comparet, director at the UK-based International Society for Neglected Tropical Diseases, says studies such as this, which can support the clinical management of at-risk groups, are vital amid the “alarming” global progression of dengue.

“With a vast majority of cases in resource-scarce countries, the already vulnerable health systems are easily overwhelmed during dengue outbreaks with children significantly at risk of potentially fatal complications,” Comparet told SciDev.Net.

With no treatments currently available, further research to better understand and quantify the risks of progression to severe dengue in children “is both urgent and crucial”, she added.