Chau Bui, Padma Narasimhan, Raina MacIntyre.
October 13th 2016
Recent world events, such as the 2014 Ebola epidemic, have brought public attention to challenges imposed by emerging and re-emerging infectious diseases. The unprecedented scale of the Ebola epidemic demonstrated how severely an epidemic can affect countries with limited health capacity. Travel has emerged as a major vector for the international spread of infections, as demonstrated by the global spread of SARS and Zika virus. Large scale epidemics or pandemics not only require global public health responses, but also calls upon social, economic and security sectors.
India’s distinctive demographic profile and geographic position presents a unique challenge to infectious disease management. The country is one of the world’s most populated nations, with a substantial proportion of the population living in impoverished areas where infectious diseases can spread exponentially (1, 2). Geographically, the country lies within the distribution zone of important disease vectors such as the Aedes aegypti mosquito (which spreads dengue and Zika virus), and the country is subject to annual monsoon seasons which perpetuate mosquito borne diseases such as Dengue, Japanese Encephalitis and Chikungunya (3).
In 2015, India saw its largest recorded dengue outbreak, with national authorities confirming almost 100,000 cases and 220 deaths (almost double that of the preceding year) – the actual number of cases and deaths are expected to be much higher with underreporting and surveillance a known issue in India (1, 4, 5). The 2015 dengue outbreaks in India gained considerable international attention, with reports of public and private hospitals overrun with dengue patients, bed-sharing, and hospitals having to turn away sick patients, which led to a controversial decision to cancel leave for doctors and paramedical staff (1, 5, 6). With the 2016 monsoon expected to be heavier than last year’s, there is an expectation of even more cases of mosquito borne disease (5). So far this year 180 dengue cases have been reported, in addition, a chikungunya epidemic is suspected to be occurring, however a lack of facilities capable of confirming chikungunya infection, means that the epidemic in unlikely to be officially reported (7).
Recurrent epidemics of encephalitis (inflammation of the brain) of unknown cause have also occurred in India (8). Between 2008 and 2014, there have been more than 44,000 cases and nearly 6,000 deaths from encephalitis in India, particularly in Uttar Pradesh and Bihar. This year has also seen a rise in encephalitis, over 125 children reported to have died in Baba Raghav Das Hospital, Gorakhpur alone, with nearly 400 children being treated for the disease (9, 10). As a response to these figures, there has been a recent push for encephalitis to be the list of national notifiable diseases (9-11). It is also critical to identify the virus or pathogen causing these large outbreaks.
The pandemic strain of influenza A(H1N1) cases in India caused a major epidemic since 2012, with 39,000 cases and 2500 deaths reported in 2015, (compared to 1000 cases and 218 deaths reported the preceding year) (12, 13).Following the 2009 pandemic, India saw a resurgence of this virus in the 2012-13 winter, and a progressive worsening resurgence since December 2014. The death rate in India was vastly higher than other countries, over 6% compared to global death rate of 0.02% in 2009. Hospitals and clinicians reported much more severe influenza disease than they had seen previously, confirmed the very high mortality. Questions have arisen about whether the virus in India had mutated to cause such severe disease, but genetic information is very sparse, and there is an urgent need for genetic research on the influenza virus in India. The lack of genetic surveillance data on influenza in India raises a larger question about infectious diseases surveillance.
One of the main challenges for surveillance of infectious diseases in India is lack of reporting from the private healthcare sector, which delivers healthcare to more than 75% of the population. It is imperative to incorporate the private health sector in disease surveillance programs, without which there will be severe under-reporting of cases. A clear cut example is under-reporting of cases in Tuberculosis. India has the highest burden (2 million new cases estimated) in the world and a recent report published in the Lancet Infectious Diseases journal revised the country’s Tuberculosis case burden to an additional 2.2 million cases every year (14). Private healthcare sector is usually the first point of contact for several of these patients, therefore a vital link in the disease control mechanism. A robust and an easy-to-use web based or a mobile based surveillance system can be a boon for the country’s disease surveillance program. In addition, adequate measures to improve education and awareness among the private healthcare providers should also be ensured.
Whilst there has been considerable progress in developing India’s health system in recent years, including the establishment of their Integrated Disease Surveillance Programme (IDSP) in 2004, there are still critical health systems gaps to address in public health and infectious diseases (12). Travel and globalisation mean that infectious diseases spread around the world rapidly, and that all countries must be prepared for epidemics. Research done at UNSW showed that the country of greatest risk of importation of MERS coronavirus from the Middle East is India, because of the large number of Haj pilgrims from India. The epidemic of MERS in South Korea which resulted from a failure to screen for MERS when a return traveller presented to hospital, highlights the global nature of epidemics. There is a need for developing better capacity to respond to large-scale epidemics, epidemiological capacity to analyse outbreaks, an increased pool of skilled public health practitioners in India, and laboratory capacity to appropriately diagnose diseases (12). All of these challenges are indeed opportunities to improve disease surveillance, response capacity and preparedness for epidemics in India
1. The L. Dengue challenges India's health system. The Lancet. 2015;386(10000):1212.
2. The Times of India. By 2017, India's slum population will rise to 104 million (reported Dipak Kumar Dash Aug 20, 2013) 2013 [cited 2016 22 August]. Available from: http://timesofindia.indiatimes.com/india/By-2017-Indias-slum-population-will-rise-to-104-million/articleshow/21927474.cms.
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4. Shepard DS, Halasa YA, Tyagi BK, Adhish SV, Nandan D, Karthiga KS, et al. Economic and disease burden of dengue illness in India. The American journal of tropical medicine and hygiene. 2014;91(6):1235-42.
5. The Times of India. Delhi running out of hospital beds as dengue cases cross 1,800 2016 [cited 2016 22 August]. Available from: http://timesofindia.indiatimes.com/city/delhi/Delhi-running-out-of-hospital-beds-as-dengue-cases-cross-1800/articleshow/48964660.cms.
6. Bennett J. India faces worst dengue fever outbreak in years with more than 6,500 confirmed cases (By South Asia correspondent James Bennett, Updated 5 Oct 2015) 2015 [cited 2016 22 August ]. Available from: http://www.abc.net.au/news/2015-10-05/india-in-grip-of-worst-dengue-fever-outbreak-in-years/6826916.
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8. Kelly R. Acute Encephalitis Syndrome Outbreaks in India – an ongoing puzzle.: School of Public Health and Community Medicine; 2014 [cited 2016 August 31]. Available from: https://sphcm.med.unsw.edu.au/infectious-diseases-blog/acute-encephalitis-syndrome-outbreaks-india-%E2%80%93-ongoing-puzzle.
9. The Times of India. Encephalitis to be made 'notifiable disease': Govt (news article published on 11 Aug 2016) 2016 [cited 2016 22 August]. Available from: http://timesofindia.indiatimes.com/city/delhi/Encephalitis-to-be-made-notifiable-disease-Govt/articleshow/53651028.cms.
10. NDTV India News. Encephalitis To Be Made 'Notifiable Disease': Government 2016 [cited 2016 August 22]. Available from: http://www.ndtv.com/india-news/encephalitis-to-be-made-notifiable-disease-government-1443010.
11. The Times of India. States should draw up plans to fight diseases: Minister 2016 [cited 2016 22 August]. Available from: http://www.thestatesman.com/news/india/states-should-draw-up-plans-to-fight-diseases-minister/157064.html.
12. Cousins S. Death toll from swine flu in India exceeds 2500. Bmj. 2015;351:h4966.
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14. Arinaminpathy N, Batra D, Khaparde S, Vualnam T, Maheshwari N, Sharma L, et al. The number of privately treated tuberculosis cases in India: an estimation from drug sales data. The Lancet Infectious Diseases. 2016.