REVIEW ARTICLE

An Update on Emerging Infectious Diseases– A Global Public Health Threat

Bratati Banerjee*, Rupsa Banerjee**

*Professor, Department of Community Medicine, Maulana Azad Medical College, New Delhi
** PGT cum Tutor, Dept. of Community Medicine, Kempegowda Institute of Medical Sciences, Bangalore

Introduction

Over the last decades there has been a rise of diseases caused by newly identified and previously unknown infectious agents, leading to global public health threat. In 1992 the Institute of Medicine (IOM), USA, published a report on emerging and re-emerging infections and the problem was finally given its due attention.1

Factors associated with emergence of infectious diseases

IOM in its report in 1992 identified various factors that contributed to the emergence of newer infections. To this list several others were added in 2003. All these factors may be grouped under four broad domains and are ultimately related to the three components of the epidemiological triad, which converge to result in emergence of diseases. The domains are:1,2

  1. Genetic and biological factors;
  2. Physical environmental factors;
  3. Ecological factors; and
  4. Social, political, and economic factors.
Table 1: Factors responsible for emergence of infectious diseases
Agent Host Environment
-Genetic/microbial
adaptation/ change
-Polymicorbial diseases 
-Human susceptibility to infection
-International travel and commerce
-Human demographics and behaviour
-Intent to harm (bioterrorism)
-Occupational exposures
-Inappropriate use of antibiotics
-Climate and weather
-Changing ecosystems
-Economic development and land use
-Technology and industry
-Poverty and social inequality
- Lack/breakdown of public health services
- Animal population
- War and famine
- Lack of political will

Major emerging infectious diseases in the world

Of the EIDs identified about 60% were caused by zoonotic pathogens, and 23% were vector borne diseases. According to Jones the predicted emerging disease hotspots due to zoonotic diseases and vector borne pathogens are more concentrated in lower latitude developing countries.3

Table 2: Major etiologic agents causing infectious diseases newly identified in the last four decades 199 2011
Year Agent Disease
1973 Rotavirus Major cause of infantile diarrhoea worldwide
1975 Parvovirus B19

Fifth disease; Aplastic crisis in chronic haemolyticanaemia

1976 Cryptosporidium parvum Acuteenterocolitis
1977 Ebola virus Ebola hemorrhagic fever
1977 Legionella pneumophila  Legionnaires’ disease
1977 Hantaan virus Hemorrhagic fever with renal syndrome
1977 Campylobacter species Enteric pathogens distributed globally
1980 Human T-cell lymphotropic virus-I (HTLV-I) T-cell lymphoma—leukaemia
1981 Staphylococcus toxin Toxic Shock Syndrome associated with tampon use
1982 Escherichia coli O157:H7 Hemorrhagic colitis; haemolytic uremic syndrome
1982 Human T-cell lymphotropic virus-II (HTLV-II) Hairy cell leukaemia
1982 Borreliaburgdorferi Lyme disease
1983 Human immunodeficiency virus Acquired immunodeficiency syndrome
1983 Helicobacter pylori Gastric ulcers
1985 Enterocytozoonbieneusi Microsporidiosis diarrhea
1986 Cyclosporacayatanensis Diarrhoea
1988 Hepatitis E Hepatitis
1988 Human herpesvirus-6 (HPV-6) Roseolasubitum
1989 Ehrlichiachaffeensis Human ehrlichiosis
1989 Hepatitis C Parenterally transmitted non-A, non-B hepatitis
1991 Guanarito virus Venezuelan hemorrhagic fever
1991 Encephalitozoonhellem .......
1991 New species of Babesia Babesiosis haemolytic disease
1992 Vibrio cholerae O139 New strain associated with epidemic cholera
1992 BartonellaRochalimaeahenselae Cat-scratch disease; bacillary angiomatosis
1993 Hantavirus isolates

Hantavirus cardiopulmonary syndrome (HCPS)

1993 Encephalitozooncunculi ......
1994 Sabiá virus Brazilian hemorrhagic feve
1994 Yersinia Pestis Plague
1995 Ebola virus Ebola haemorrhagic fever
1995 Human herpes virus-8 (HHV-8) Kaposi’s sarcoma
1996 New variant Australian bat lyssavirus Crutzfield Jacob disease
1997 H5N1 Influenza virus Avian Influenza
1997 Methicillin-Resistant Staphylococcus Aureus  (MRSA)         Skin infections
1998 Nipah virus Viral  encephalitis
1999 West Nile virus Encephalitis
2000 Rift valley fever virus Rift valley fever
2001 Bacillus anthrasis Anthrax
2002 Vancomycin-ResistantStaphylococcus Aureus (VRSA)  Skin infections
2003 Corona virus Severe Acute Respiratory Syndrome
2004 Influenza A H5N1 Avian Influenza
2006 XDR-TB Tuberculosis
2009 Influenza A H1N1 Pandemic A (H1N1) 2009 Influenza
2010 Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-beta-lactamase 1 (NDM-1) Multi drug resistant bacterial infection
2011 ArtemisininResistant Malaria Malaria
2012 GII.4 Sydney (norovirus) Acute gastroenteritis
2012 Middle East respiratory syndrome coronavirus (MERS-CoV) Middle East respiratory syndrome
2013 Influenza A H7N9H7N9 Avian Influenza
2014 Hepnivirus Acute Encephalitis Syndrome &Meningitis
2014 NovelThogotovirus Febrile Illness
Strategies for prevention and control of emerging infectious diseases International action 4-6
  1. Surveillance
  2. Scientific advice
  3. Preparedness and response
  4. Health communication
Presently ECDC has proposed shifting its focus from SMP to Disease Specific Programme (DSP).

National action 7-10

Steps have been taken to address this threat in India too by Indian Council of Medical Research (ICMR), Integrated Disease Surveillance Project (IDSP) National Centre for Disease Control (NCDC). These are:
Several international and national publications give updates regarding this problem. These are:

Conclusion

There is currently a serious global threat to public health because of emerging infectious diseases. Consorted efforts must be made by international health agencies and all governments, to contain this problem.

References

  1. Institute of Medicine. Microbial Threats to Health: Emergence, Detection and Response. (Smolinski, Hamburg & Lederberg eds.) Washington DC: The National Academies Press: 2003. Available from:
    http://www.nap.edu/openbook.php?isbn=030908864X. Last accessed on 23.02.2013.
  2. Morens DM, Fauci AS (2013) Emerging Infectious Diseases: Threats to Human Health and Global Stability. PLoS Pathog 9(7): e1003467. doi:10.1371/journal.ppat.1003467.
  3. Jones KE, Patel N, Levy MA, Storeygard A, Balk D, Gittleman JL et al. Global trends in emerging infectious diseases; Nature 2008; 451: 990–993.
  4. CDC. Addressing Emerging Infectious Disease Threats: A Prevention Strategy for the United States Executive Summary. Morbidity and Mortality Weekly Report. 1994; 43(RR-5).
  5. ECDC. Strategies for disease-specific programmes 2010-2013. Stockholm: European Centre forDisease Prevention and Control; 2010. Available from http://ecdc.europa.eu/en/publications/Publications/100714_COR_Strategies_for_disease-specific_programmes_2010-2013.pdf. Last accessed on 15.05.2015.
  6. World Health Organisation. South-East Asia Regional Office 2005 Combating emerging infectious diseases (SEA-CD-139). Available from http://www.searo.who.int/entity/emerging_diseases/documents/b0005.pdf. Last accessed on 15.05.2015.
  7. Kant L. Combating emerging infectious diseases in India: Orchestrating a symphony. J. Biosci. 33(4), November 2008, 425–427.
  8. Integrated Disease Surveillance Project (IDSP). Ministry of Health and Family Welfare, Government of India. Available from idsp.nic.in. Last accessed on 15.05.2015.
  9. Two years (2009-2011) Achievements and new initiatives. Ministry of Health and Family Welfare, Government of India. Available from http://pib.nic.in/archieve/others/2011/may/d2011052501.pdf. Last accessed on 15.05.2015.
  10. Centers for Disease Control and Prevention. CDC in India. Factsheet. 2013. Available from http://www.cdc.gov/globalhealth/countries/india/pdf/india.pdf. Last accessed on 15.05.2015.
  11. World Health Organisation. The Weekly Epidemiological record. Available from http://www.who.int/wer/en/. Last accessed on 15.05.2015.
  12. Centers for Disease Control and Prevention. Emerging Infectious Diseases journal. Available from http://wwwnc.cdc.gov/eid/). Last accessed on 15.05.2015.
  13. National Centre for Disease Control. CD Alert: An important tool for Rapid Dissemination of Information towards Control of Diseases. NCDC, Directorate General of Health Services, Government of India. Available from http://www.nicd.nic.in/index2.asp?slid=505&sublinkid=166. Last accessed on 15.05.2015.