JKIMSU, Vol. 6, No. 4, October-December 2017 ISSN 2231-4261 REVIEW ARTICLE Viral Diseases of Public Health Importance in India: Current Priorities with Special Emphasis on Prevention Mageshbabu Ramamurthy1*, Sathish Sankar1, Balaji Nandagopal1, Gopalan Sridharan1, Arun R.Risbud2 1Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital and Research Centre, Sripuram-632055 (Tamil Nadu) India, 2Directorate of Research, Krishna Institute of Medical Sciences Deemed University, Karad-415110 (Maharashtra) India Abstract: Introduction: India faces problems with both communicable and non India is a vast geographical area with different communicable diseases. The major non commu- habitats. We have urban centres, rural areas, tribal nicable diseases are cancer, cardiovascular disease and areas and vast forested areas, each of them posing diabetes mellitus. This article focuses on commu- different public health challenges. India has nicable diseases (infectious diseases) especially viral problems of public health importance including infections of public health importance. The infections both communicable (infectious disease) and non- include bacterial, parasitic and viruses. It could be said that fungal infections by the nature of the spread are communicable diseases [1]. The present article not of public health concern. The viral infections are focuses on communicable diseases, especially, transmitted by the respiratory route, water and food viral infections. Historically, viral infection borne route, vectors and blood and blood products, outbreaks have significantly outnumbered the sexual route and are of major concern. Efforts are outbreaks of other etiologies. India has aimed at early detection, prevention by use of vaccines successfully controlled or eradicated several and sentinel surveillance. For the success of public communicable diseases by introducing sentinel health programmes sentinel surveillance of diseases is surveillance and vaccine intervention as well as mandatory. India has got several programme public health measures. The term sentinel initiatives addressing the problem. The programs surveillance refers to establishment of field units include IDSP, VBDCP and NACO. The approximate capable of accurate clinical diagnosis, laboratory cumulative annual prevalence of infectious disease in India ranges from 100 to 200 million individuals diagnosis and data collection. The surveillance affected in one year. India should aim to improve case site could be hospital or a community based field detection by strengthening laboratory services with epidemiology unit. A long term data and the data manpower training and nationwide quality control gathered at regular intervals at such field units are scheme, sentinel surveillance activity and prevention of vital importance not only for investigation of by improving the efficiency and scope of UIP. Also, epidemics and outbreaks but also for predicting creation of a single portal of infectious disease data such outbreaks. Universal Immunization handling hub to collect information from different Programme (UIP) under the Ministry of Health sources will help avoid overlap and duplication of and Family Welfare (MoHFW) has been reporting. significantly expanded by inclusion of newer Keywords: Epidemiology, Emerging, Dengue virus, vaccines over the last fifty years. Successful HIV, Acute Encephalitis Syndrome Ó Journal of Krishna Institute of Medical Sciences University 1 JKIMSU, Vol. 6, No. 4, October-December 2017 Mageshbabu Ramamurthy et al. control of several childhood illnesses like research facilities. The national agencies like diphtheria, whooping cough, poliomyelitis and Integrated Disease Surveillance Programme measles has been achieved through vaccination in (IDSP) use the existing laboratory services in infancy and childhood booster doses. Previously, medical colleges and District hospitals to collect as part of the global programme, small pox was information on several diseases. Along with certain eradicated in India forty years ago [2]. Presently, other viral infections such as Japanese encephalitis poliomyelitis caused by wild poliovirus has been surveillance, Dengue fever surveillance and eradicated in the country [3]. However, Acute control is presently under the National Vector Flaccid Paralysis (AFP) polio-like-illness caused Borne Disease Control Programme (NVBDCP) by Non-polio Enteroviruses (NPEV) is active established in 2004. In the face of the global throughout the country and is monitored through influenza pandemic a network of influenza the AFP control programme under the auspices of surveillance laboratories was established in 2006 WHO and MoHFW which also ensures that the under IDSP. A Multisite virological Influenza cases of poliovirus infection and disease are not surveillance in India was started by Indian Council missed [4]. of Medical Research in 2004. The National AIDS The communicable diseases of public health Control Programme (NACP), launched in 1992 as importance include those that can occur as small a part of National Aids Control Organization outbreaks in communities, epidemics in (NACO) has paid rich dividends. communities and pandemics that affect large areas Epidemiological Aspects of Viral Diseases: of the country. Several infectious diseases have Viral diseases active in a country take three major the potential to cause severe morbidity and forms, they include, Epidemic: A typical episode of unacceptable mortality in the community [5]. a viral disease occurrence in a population or region Presently, among the agents, including bacterial of the country not previously affected at that and parasitic, that are of public health concern, magnitude. The frequency of viral disease known viral infections top the list. The acute viral to occur in a given community is exceeded during infections with wide spread prevalence in several an epidemic. The appearance and spread of a new parts of the country include dengue fever, etiological agent of a given infectious syndrome chikungunya fever, viral diarrheas and respiratory also constitutes an epidemic. The term outbreak infections [6-8]. There is a major public health may be used if the number of human cases is small problem with enterically transmitted hepatitis and occurs only in a restricted area of a viral agents like Hepatitis A Virus (HAV) and metropolitan city or contiguous rural area (few Hepatitis E Virus (HEV) as well [9]. villages). Endemic: The continuous activity of a Blood borne viral infections which are chronic in viral agent in the community at low levels affecting nature are widely prevalent in all parts of India and small number of people usually is the characteristic include Human Immunodeficiency Virus (HIV), of an endemic viral infection. Pandemic: When Hepatitis B Virus (HBV) and Hepatitis C Virus large number of people are affected over a wide (HCV) [10]. The identification of the geographic area inclusive of parts of the country or communicable agents is achieved in different areas the entire country and several continents of the by various state and central government health / globe by a viral agent [11]. Ó Journal of Krishna Institute of Medical Sciences University 2 JKIMSU, Vol. 6, No. 4, October-December 2017 Mageshbabu Ramamurthy et al. Use of standard case definitions is vital for defined as those that were previously major health investigating and describing an outbreak/ problems either in certain countries or worldwide. epidemic. Pattern of occurrence of these infections/diseases They may be seen to be seasonally related to over the previous few years suggested that they climatic conditions or vector density. Such would have declined significantly, but again infections include Dengue fever and Japanese started spreading in human populations [14]. encephalitis. Outbreaks of infections if not Several features which include changing weather controlled have the potential to become pattern due to global warming contributing to epidemics. It has been pointed out that small vector boom, poor sanitation and water hygiene outbreaks may disappear due to lack of critical due to overcrowding and increased travel resulting population size of susceptible individuals. On the in spread through carriers or asymptomatic contrary, when a threshold of infected individuals infected individuals and change in life styles. In is reached among the population of susceptible this category, Arthropod-borne viruses individuals (critical community size), epidemics (arboviruses) have become major public health are prone to occur [12]. Certain epidemics have problems in India, with considerable morbidity persisted over long periods like HIV/AIDS now and mortality. The South East and South Asian active in the country over the last thirty years. regions are particularly affected because of both Some infections have originated in certain climatic and environmental conditions conducive geographical areas and spread to different regions for increase in vector population close to human and countries. These infections which involve habitation. Infections such as Dengue (DEN) large number of people and spread over vast areas fever, Japanese Encephalitis (JE), West Nile Virus constitute a pandemic also referred to as global (WNV), Chikungunya (CHIK) fever, Kyasanur pandemic. We have had a major pandemic of Forest Disease Virus (KFDV), are continuing to influenza A virus infection between 2009 and increase in the different geographical regions of 2010. In addition, preventable iatrogenic the country.