Emerging and Re-emerging Infectious Diseases

1. Emerging and Re-emergingInfectious Diseases Ashry Gad Mohamed, DrPH Prof. of Epidemiology College of Medicine, KSU.

2. Emerging infectious diseases: Infectious diseases that have newly appeared in a population. Global : Regional: Re-emerging Diseases: Diseases’ incidence in human has increased during the last 20 years or threatens to increase in the near future. Global: Regional:

4. Emerging Infections in the World since 1973 1973 Rotavirus Enteritis/Diarrhea 1976 Cryptosporidium Enteritis/Diarrhea 1977 Ebola virus VHF 1977 Legionella Legionnaire’s dz 1977 Hantaan virus VHF w/ renal flr 1977 Campylobacter Enteritis/Diarrhea 1980 HTLV-1 Lymphoma 1981 Toxin prod. S.aureus Toxic Shock Synd. 1982 E.coli 0157:H7 HUS 1982 HTLV-II Leukemia 1982 Borrelia burgdorferi Lyme disease

5. 1983 HIV AIDS 1983 Helicobacter pylori Peptic ulcer dz 1988 Hepatitis E Hepatitis 1989 Hepatitis C Hepatitis 1990 Guanarito virus VHF 1991 Encephalitozoon Disseminated dz 1992 Vibrio cholerae O139 Cholera 1992 Bartonella henselae Cat scratch dz

6. 1993 Sin Nombre virus Hanta Pulm. Synd. 1994 Sabia virus VHF 1994 Hendra virus Respiratory dz 1995 Hepatitis G Hepatitis 1995 H Herpesvirus-8 Kaposi sarcoma 1996 vCJD prion Variant CJD 1997 Avian influenza (H5N1) Influenza 1999 Nipah virus Encephalitis 1999 West Nile virus Encephalitis 2001 BT Bacillus anthracis Anthrax 2003 Monkeypox Pox SARS-CoV SARS H5N1 Avian Influenza

8. Economic Impact of Selected Infectious Diseases

9. Factors responsible for emerging of infections. I-Ecological changes and Agricultural development. Placing the people in contact with a natural reserviour or host of a hitherto unfamiliar, but usually already present,

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15. Dams: High dam in Egypt Slowed water flaw allowed snails to go south introduced S. mansoni in Upper Egypt Increased its occurrence in Nile Delta. Senegal Dam Lakes in Mauritania Rift Valley Fever outbreak 1987.

16. Climate and Weather

17. Higher ocean temps increase Vibrio parahaemolyticus (shellfish) Some soil pathogens carried by dry dusty winds (Coccidiodes)

18. II- Changes in Human demographics and behaviours Inflation of population size Insufficient infrastructures Use open containers for water Breading mosquitos Dengue fever in Asia

20. War and Famine

21. III-International travel and Commerce. 365 days to circumnavigate the globe…now it takes 36 hours -used to quarantine ships, but 36 h faster than disease incubation 400 million people per year travel internationally increased incidence of both Tuberculosis and Influenza transmission on long flights

22. -Transportation of products is an increased concern. -rapid transport of disease harboring fresh products. -transport of livestock facilitates movements of viruses and arthropods (especially ticks) Travel and HIV/AIDS. -Silk route and plague. -Slaves trade and yellow fever. -Migration to new world and smallpox. Cholera and Hajj.

23. IV- Technology and industry Modern mass production increased the chance of accidental contamination and amplifies the effect of such contamination. -Contamination of hamburger meat by E.coli strains causing haemolytic uraemic syndrome. -Feeding cattle by byproducts of sheep causing bovine spongiform encephalitis.

24. Concentrating effect of blood and nasocomial infections e.g. Ebola fever by contaminated hypodermic apparatus. New diagnostic technology lead to identification of previously unknown microbes for known diseases e.g. Helicobacter pylori and peptic ulcer, human herpes virus 6 and roseola. Medical technology People living longer, but have weaker immune systems. Blood & organ transplantation transmit infections.

25. V-Microbial Adaptation and Change

26. Increased antibiotic resistance with increased use of antibiotics in humans and food animals (VRE, VRSA, penicillin- and macrolide-resistant Strep pneumonia, multidrug-resistant Salmonella,….) Increase virulence (Group A Strep?) Jumping species from animals to humans (avian influenza, HIV?, SARS?)

27. Parasites, too: Time to Development of Resistance to Antimalarial Drugs

28. I just show this one data slide from the National Nosocomial Infection Surveillance System to point out the ever-increasing trend in U.S. hospitals of how Vancomycin-resistant Enterococci are gaining a percentage of the action in hospital-acquired infections -- in the 1990s.I just show this one data slide from the National Nosocomial Infection Surveillance System to point out the ever-increasing trend in U.S. hospitals of how Vancomycin-resistant Enterococci are gaining a percentage of the action in hospital-acquired infections -- in the 1990s.

30. VI- Breakdown of public health measures. -Decrease in choline in water supplies lead to rapid spread of cholera in South America. Non functioning water plant in Wisconsin, USA lead to outbreak of waterborne cryptosporidium.

31. Inadequate vaccinations and Diphtheria in former USSR independent countries. Discontinued mosquito control efforts and dengue and malaria re-emergence.

32. Major Factors Contributing to the Emergence of Infectious Diseases 1. Human demographics and behavior 2. Technology and industry 3. Economic development and land use 4. International travel and commerce 5. Microbial adaptation and change 6. Breakdown of public health measures Institute of Medicine Report 1992

33. Progress in the Eradication of Dracunculiasis (Guinea Worm) 1981 -- > 4,000,000 cases 1986 -- 3,500,000 cases 1989 -- 890,000 cases 1992 -- 374,000 cases 1995 -- 129,000 cases 1998 -- 79,000 cases (61%, Sudan) 1999 – 80,000 cases (70%, Sudan) 2000 -- 70,000 cases (73%, Sudan) 2001 -- 60,000 cases (78%, Sudan) 2002 -- 50,000 cases (74%, Sudan) 2003 -- 31,000 cases (62%, Sudan; 27%, Ghana) 2004 -- 16,026 cases (45%, Sudan; 45%, Ghana) 2005 -- 10,715 cases vs. 14,418 in 2004 (Jan-Oct)(61%, Sudan; 29%, Ghana) [Down from 20 to 10 countries; 5 of them had fewer than 100 cases in 2005]