key: cord-0039778-2p9aclr2
authors: Kashyap, Bineeta; Prakash, Anupam
title: Emerging and re-emerging infectious diseases: A perpetual threat
date: 2015-08-18
journal: nan
DOI: 10.1016/j.injms.2015.07.007
sha: a5e3787d8c98431a1a2314f560ee0e0e0bcc4206
doc_id: 39778
cord_uid: 2p9aclr2

nan

Emerging infections are mostly caused by pathogens already present in the environment, brought out of obscurity or given a selective advantage to infect new host populations. An expert committee from Center for Disease Control (CDC) identified six major factors that contribute to disease emergence and re-emergence:

1. Changes in human demographics and behavior, 2. Advances in technology and changes in industry practices, 3. Economic development and changes in land-use patterns, 4. Dramatic increases in volume and speed of international travel and commerce [ 3 2 _ T D $ D I F F ]movement not only of people but of animals, foodstuffs, and other commodities, 5. Microbial adaptation and change, and 6. Breakdown of public health capacity required for infectious diseases at the local, state, national, and global levels. 5 The current spate of attention belies the fact that emerging infections are a recent phenomenon and suggest that they have always played a major role in human history. In addition to the AIDS, severe acute respiratory syndrome (SARS[ 2 4 _ T D $ D I F F ] ), and influenza pandemics that have had severe global impact, a i n d i a n j o u r n a l o f m e d i c a l s p e c i a l i t i e s 6 ( 2 0 1 5 ) 7 9 -8 1 Available online at www.sciencedirect.com ScienceDirect journal homepage: www.elsevier.com/locate/injms continual evolution with consequent impact of a wide range of emerging and re-emerging infectious diseases is evident:

, and Hanta virus hemorrhagic fever with renal and pulmonary syndrome have been highly virulent but restricted in their spread and hence have been more medical curiosities than global public health threats. Infections [ 3 5 _ T D $ D I F F ] such as drug-resistant malaria have affected large number [ 3 6 _ T D $ D I F F ] of people, but due to the demographic distribution[ 3 7 _ T D $ D I F F ] , they are more of concern in a geographically restricted region rather than being a global public health threat. Hepatitis C virus, first identified in 1989, is now the most common cause of transfusion hepatitis globally[ 3 8 _ T D $ D I F F ] , and has a tremendous global impact in terms of chronicity and risk for developing liver cirrhosis and/or liver cancer. 6 A recent report from Delhi emphasizes the importance to have a high index of suspicion for rickettsial diseases in cases of fever occurring in the monsoon and post-monsoon season in Delhi and adjoining areas[ 5 1 _ T D $ D I F F ] , as rickettsial diseases may become a serious public health problem in [ 5 2 _ T D $ D I F F ] the absence of diagnosis or misdiagnosis. 7 The perpetual nature of the emergence of infectious diseases poses a volatile ever-changing challenge[ 5 3 _ T D $ D I F F ] , and there is no doubt that new and previously unrecognized infections will continue to infect globally. It may be possible that some of these newly emerging infections could be more a function of increased detection than actual emergence in human population[ 5 4 _ T D $ D I F F ] ; the striking example of which is Legionella bacterium responsible for the high-mortality pneumonia known as Legionnaires' disease. Today, the contribution of genomics and proteomics in the discovery of new infectious diseases and in the better understanding of the pathogenesis of the existing ones has substantially improved disease surveillance[ 5 5 _ T D $ D I F F ] , and helps elucidate host susceptibility factors and host responses to treatment of infections. In response to continuous emergence and re-emergence of infectious diseases, various national and international organizations [ 5 6 _ T D $ D I F F ] such as WHO, CDC, the National Institute of Health (NIH), Department of Defense[ 5 7 _ T D $ D I F F ] , and the Food and Drug Administration (FDA) have collaborated to develop strategic plans to combat the menace. A five pronged strategy comprising epidemic preparedness, appropriate health infrastructure, effective risk communication, research, and political commitment for partnership building has been suggested for countries of the South-East Asia region (WHO South-East Asia Regional Office, 2005). 4 

Emerging infectious diseases: a CDC perspective

Scrub [ 6 8 _ T D $ D I F F ] typhus -a re-emerging infection

Scrub typhus [ 3 2 _ T D $ D I F F ] -an emerging public health problem in Delhi!

E-mail address: dr_bineetakashyap@yahoo.co.in (B. Kashyap) Available online 18