The annual number of dengue cases in India is 282 times higher than what is officially reported, and the disease inflicts an economic burden on the country of at least USD 1.11 billion each year, according to a new scientific study published on Wednesday.
“We found that India had nearly six million annual clinically diagnosed dengue cases between 2006 and 2012almost 300 times greater than the number of cases that had been officially reported,” said Donald Shepard, lead author of the study.
The study, led by researchers at Brandeis University, the INCLEN Trust International in New Delhi, and the Indian Council of Medical Research Centre for Research in Medical Entomology (CRME) in Madurai has been published in the American Journal of Tropical Medicine & Hygiene. Yet we believe even that number may be low because dengue reporting is better in the area we studied in the state of Tamil Nadu than in most other Indian states,” Shepherd said.
In recent decades, dengue outbreaks in India have become larger and more frequent. “Good data on the incidence and cost of the illness have been lacking due to gaps in how information on individual cases is collected,” said Narendra Arora, executive director of INCLEN.
Dengue, a viral disease transmitted by Aedes mosquitoes, is a serious global public health problem, infecting 50 to 390 million people each year in more than 100 countries and resulting in at least 20,000 deaths annually.
India is believed to have more cases of dengue than any other country, and except for a slight dip in 2011, the incidence rate has grown steadily there in recent years.
In 2013, India’s National Vector Borne Diseases Control Program reported an annual average of 20,474 dengue cases and 132 dengue-related deaths since 2007, but infectious disease experts believe those official numbers likely reflect only a small fraction of actual cases, the report said.
As for dengue’s economic burden, the researchers found that the total direct medical cost to India was USD 548 million per year, or about USD 94.85 per patient.
“Dengue is therefore more expensive to treat in India than tuberculosis,” the report said.
Based on other research that examined the economic burden of dengue on low- and middle-income countries elsewhere in the world, the study researchers determined that the direct medical costs of the disease represent only 49 per cent of the disease’s overall costs.
“The overall annual economic cost of dengue in India, therefore, is about USD 1.11 billion annually,” the report said.