Emerging infections. Perspectives. Examples. How to predict/ prepare/ prevent/ handle

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2 Emerging infections Perspectives Examples How to predict/ prepare/ prevent/ handle

3 Perspective on infectious disease One can think of the middle of twentieth century as the end of the most important social revolutions in history, the elimination of the infectious disease as a significant factor in social life Sir McFarland Burnet, 1962 It is time to close the book on infectious diseases and pay more attention to chronic ailments such as cancer and heart disease.. - William H Steward, 1968

4 Emerging infectious diseases

5 Emerging infectious diseases

6 Emerging infectious diseases

7 Emerging infectious diseases

8 Outbreak reports WHO 2007 Avian influenza situation in Indonesia Meningococcal disease in Uganda Rift Valley Fever in Kenya Yellow fever in Togo Poliomyelitis in Chad Extensively Drug-Resistant Tuberculosis (XDR-TB) in United States of America air passenger Marburg haemorrhagic fever in Uganda Ebola haemorrhagic fever in the Democratic Republic of the Congo

9 Perspective on infectious disease Emerging infectious diseases present one of the most significant health and security challenges facing the global community.... We are committed to ensuring that American citizens have the best protection possible from emerging infectious disease, and that means coordinated, comprehensive approach at both the national and international levels. - Vice President Albert Gore, In the highly interconnected and readily traversed global village of our time, one nation s problem soon becomes every nation s problem... Microbial Threats to Health: Emergence, Detection, and Response, Institute of Medicine, March 2003.

10 Health and development Creating the circumstances for the spread of infectious diseases

11 Emerging virus infections in the last decennia

12 Mobility

13 Demography: rapidly Increasing Human Population 1 billion people until Billion people in 2000 ~9.4 to 11.2 Billion in 2050 Source: United Nations, World Population Prospects, The 1998 Revision; and estimates by the Population Reference Bureau.

14 Climate changes

15 Climate changes

16 Identifying candidate diseases for early warning systems by WHO Cholera malaria meningococcal meningitis dengue/ dengue hemorrhagic fever leptospirosis yellow fever japanese and St Louis encefalitis rift valley fever african trypanosomiasis leishmaniasis west nile virus murray valley fever and Ross rive virus

17 Outbreak examples SARS HIV Malaria Avian Influenza Hepatitis B Hemorrhagic fevers...

18 SARS

19 SARS Outbreak In November 2002, highly contagious and severe atypical pneumonia were observed in the Guangdong Province of southern China The virus was spread to Hong Kong in February 2003 by a doctor who died 10 days after admission into local hospital a mysterious death Similar outbreaks occurred at different local communities subsequently The virus was identified by Hong Kong, the U.S. Germany in March 2003, and The Netherlands

20 Effect of Travel and Missed Cases on the SARS Epidemic Spread from Hotel M, Hong Kong Hong Kong SAR 95 HCW Guangdon g Province, China >100 close contacts A H,J A B Vietnam 37 HCW 21 close contacts H,J B A Hotel M Hong Kong C,D,E F,G K I, L,M C,D,E Singapore 34 HCW 37 close contacts F,G K Canada 18 HCW 11 close contacts I,L,M Ireland 0 HCW United States 1 HCW

21 SARS

22 SARS The Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) are investigating a worldwide outbreak of unexplained atypical pneumonia referred to as Severe Acute Respiratory Syndrome (SARS). As of 10 April 2003, over 2,500 suspected cases of SARS have been reported to WHO from nearly 20 countries; in the United States, over 150 suspected cases (about 5% of cases worldwide) have been reported to CDC from about 30 states. Of the United States cases, about 95% had traveled to outbreak areas listed in the case definition within 10 days prior to the onset of clinical illness, and the remainder had a history of close contact with a person with suspected SARS. Of these cases reported worldwide, approximately 3.5 % (over 100 cases) have been fatal. In the United States, the majority of patients have recovered or stabilized clinically without specific antiviral therapy; no fatalities have been reported as of 10 April Laboratories at CDC and elsewhere (SARS Laboratory Network organized by WHO) have detected a new coronavirus in SARS patients. Less often, a paramyxovirus (metapneumovirus) also has been found. Both are lipid-enveloped, singlestranded RNA viruses. The identification of a novel coronavirus is consistent with a potential etiologic role, but the pathogenesis of SARS remains unclear at the present early stage of research. A co- factor role of paramyxovirus in this syndrome cannot be excluded. A diagnostic test for SARS based on the detection of acute infection with the novel coronavirus is currently under development.

23 Globe Impacts of SARS Toronto airport Railway station full with people leaving Beijing The terror of the unknown is seldom better displayed than by the response of a population to the appearance of an epidemic, particularly when the epidemic strikes without apparent cause Quote from Edward Kass, 1977 Normal life affected Worldwide: 59 US$ billion China, mainland: 17.9 US$ billion, 1.3% GDP Hong Kong: 12 US$ billion, 7.6% GDP By Dr. Hu AnGang, Nov. 11, 2003 International conference of AIDS and SARS, Qinghua University, Beijing

24 HIV

25 HIV

26 HIV

27 HIV

28 Malaria

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30 How is AI spread? Animal & human populations in close proximity - farm animals and pets in/under/next to houses - live animal markets (many species from many countries) Poor agricultural practices - inadequate infection control on farms - poultry excrement used in agriculture (e.g. fed to pigs) Poor food hygiene - food preparation practices - consumption of raw/undercooked meat Frequent travel/trade involving humans and birds - movement of people/animals among farms - legal and illegal animal trade - wild bird migration

31 Avian Flu

32 What is Avian Influenza?

33 Hepatitis B distribution

34 Hepatitis B 300 miljon carriers worldwide Perinatal transmission/ horizontal transmission!/ sexual contact/ IV drugsabuse incubation 1-4 months progression from acute to chronic 90% in perinatal infection/ 20-50% between age 2-5 jaar and less than 5% in adults mortality caused by cirrhosis/ HCC (higher chance if HbeAg pos)/ decompensated livercirrhosis alcohol enhances cirrhosis

35 Cirrhosis and livercell carcinoma

36 Viral hemorrhagic fevers (VHF) Epidemiology

37 Geographic spread VHF Dengue Yellow fever Rift valley fever

38 Geographic spread VHF Ebola, Marburg Lassa Crimean-Congo HF

39 Dengue distribution

40 million Dengue infections annually million people at risk for Dengue virus transmission

41 Lassa fever Diagnosis Lassa-fever, by RT-PCR Lassa fever West Africa cases, 5000 deaths Rats shed virus via excreta Infection: direct/indirect contact Transmissible person-toperson

42 Human Ebola outbreaks in Africa Pourrut et al, Microbes Infect 2005

43 Epidemiology Marburg hemorrhagic fever First recognized in 1967 Marburg and Belgrade laboratory workers, infected monkeys from Uganda 25 cases, 7 deaths, 6 secondary cases 1975: South Africa (via Zimbabwe?) 1980: Kenya 1987: Kenya : Dem. Republic of Congo

44 Angola outbreak cases, 150 deaths

45 Outbreak management

46 How to predict/ prepare/ prevent/ handle local and global surveillance systems Public health system and mechanisms for response to emerging diseases should be based on science The governments, scientific communities and industry should work together for fighting the emerging diseases Economic development should be balanced with the social development There should be a harmonious relationship between man and nature

47 Conclusion

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