New Delhi: A new study by Indian and US researchers has revealed that the annual number of dengue fever cases in India may be almost 300 times greater than the officially reported figures.
The study led by researchers at Brandeis University’s Schneider Institute for Health Policy in Waltham, Massachusetts; the INCLEN Trust International in New Delhi; and the Indian Council of Medical Research’s Centre for Research in Medical Entomology in Madurai, Tamil Nadu has found that about 5,778,406 or around six million people in India got the viral disease between 2006 and 2012, whereas the official figures is around 20,474 cases and 132 deaths. The study is published in the American Journal of Tropical Medicine and Hygiene.
The report is also the first to use empirical data to estimate the disease’s burden and the direct and indirect costs of dengue in India. It found that the disease’s economic burden on the country is Rs 6,753 crore a year, approximately the same as what India spends every year on its national space programme.
Dr Narendra K Arora, executive director of INCLEN, told India Medical Times, “The important question we would like to highlight from this study is that – Why is there such a gross underreporting of the dengue cases in India?”
“First, the current reporting data primarily banks on the public sector whereas it is the private sector that handles 80% of the market share in healthcare sector. Second, in the public sector, reporting of cases is very poor and diagnostic kits are not generally available. Third, the current diagnostic system is flawed. Fourth, about two-third of the cases that are mild cases are not reported at all. So cumulatively, reporting is poor and about only 0.3% of the cases are reported every year,” Dr Arora explained.
“What we are saying is that it’s not some huge epidemic that has occurred. The number of cases occurring is still more or less the same, it is only underreporting that we highlighted. So, improvement in reporting standard is needed. A credible data on the incidence and cost of the illness have been missing due to gaps in how information on individual cases is collected and reported,” he added.
Dr Arora and his colleagues from US and India conducted a retrospective study of dengue patients hospitalised in Madurai district in 2009-2011. They then used that data, along with less complete disease surveillance data from 18 other states and information from a panel of dengue experts, to calculate a national estimate for annual dengue cases, including ambulatory cases.
To estimate the cost of each dengue case, the researchers analysed the medical records of 1,541 dengue patients who had been treated in 10 public and private medical college hospitals across India from 2006 through 2011. Gaps in those data were then filled in through a survey of 151 patients who had received care at a medical college hospital in Mumbai in 2012 and 2013.
Since the medical surveillance in the country is fragmented, with some areas having a better reporting mechanism than others, the study draws a mixed response from the doctors.
Dr Ashish Goel, assistant professor (medicine), University College of Medical Sciences and GTB Hospital, New Delhi, told India Medical Times, “I don’t think there is huge underreporting of the cases. Though no system has a full proof reporting mechanism, I feel there is nothing that prevents authorities reporting the number of dengue cases.”
Though, efforts by the Indian government to prevent the spread of vector borne disease are on full scale, the country still reports a large number of cases every year with a major dengue outbreak in 2013, when 75,454 cases and 167 deaths were reported.
According to the study, understanding the economic and disease burden of dengue in India is essential to assist policy makers and public health managers to prepare for and control outbreaks, and encourage international collaboration to develop and evaluate prevention, control and management measures, and technologies to control further epidemics.
Dr Sarit Sharma, associate professor, community medicine, Dayanand Medical College and Hospital, Ludhiana, told India Medical Times, “I agree that the dengue cases are underreported in India. The number of dengue cases usually surge during pre and post monsoon period at my place. Since the number of migrants is very high, they get themselves checked at various clinics and nursing homes. These clinics and nursing homes do not report the number of cases that clearly. Generally, government labs and medical colleges have a better reporting mechanism of dengue cases. So, only the cases reported by certified labs and medical colleges do not present a real picture. Actual cases are under reported.”
The economic and disease burden of dengue in India is substantially more than captured by officially reported cases, and increased control measures merit serious consideration, the study said.
This study was supported in part by Sanofi Pasteur, which is developing dengue vaccine. However, the sponsor had no control over the study content, according to the researchers.
by Vidhi Rathee