Understanding and Preparing for Emerging Disease Outbreaks

Transcription

1 Understanding and Preparing for Emerging Disease Outbreaks CAPT Ha C. Tang, D.O. US Public Health Service Adjunct Associate Clinical Professor of Dartmouth Medical School, Community/Family Medicine Dept. Deputy Chief of Family Medicine Department Disclosures: None

2 Co-authors: Reasol A. Chino, PharmD, BCACP Commander, US Public Health Service Assistant Director of Pharmacy Tuba City Regional Health Care Corp(TCRHCC) Paul Chefor, PharmD, BCACP LT Commander, US Public Health Service Director of inpatient Pharmacy Tuba City Regional Health Care Corp(TCRHCC Sita Marie Shablack, PharmD LT, US Public Health Service Advance Practice Pharmacist I Tuba City Regional Health Care Corp(TCRHCC

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4 Objectives Understand history and threats of emerging diseases. What are the likely emerging diseases of the 21 St Century. Recognize the factors leading to an emerging disease outbreak and its enduring prevalence. Recognize superspreader phenomenon What can we do at our hospital level? Thus the task is not so much to see what no one yet has seen, but to think what nobody yet has thought about that which everybody sees. Arthur Schopenhaur

5 Forethought we may have, undoubtedly, but not foresight. Napoleon Bonaparte

6 Emerging infectious diseases Infections that have recently appeared within a population or those whose incidence or geographic range is rapidly increasing or threatens to increase in the near future. Emerging infections Previously undetected or unknown infectious agents Known agents that have spread to new geographic locations or new populations

7 Emerging infections Previously known agents whose role in specific diseases has previously gone unrecognized. Re-emergence of agents whose incidence had significantly declined in the past, but reappeared. Within the past eight decades, an average of five or six emerging infectious diseases have appeared annually worldwide CDC's Early Response to a Novel Viral Disease, Middle East Respiratory Syndrome Coronavirus (MERS-CoV), September 2012 May

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9 Risk to HCP from Emerging Diseases Middle East respiratory syndrome coronavirus MERS at 1 27%, Ebola %, SARS 11 57% Risks to healthcare workers with emerging diseases: lessons from MERS- CoV, Ebola, SARS, and avian flu, by Suwantarat, Nuntra a,b ; Apisarnthanarak, Anucha in Current Opinion in Infectious Diseases- : August Volume 28 - Issue 4 - p Most notable infectious diseases of the centuries Plague Smallpox Tuberculosis

10 Plague Justinian Plague-AD 532 Great Medieval Plague-1334 Third Plague Pandemic

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12 Smallpox eradication Under a 1979 WHO agreement, the only remaining official live smallpox stocks are kept at CDC in Atlanta and the VECTOR laboratory in Novosibirsk, Russia

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14 "Our misfortunes in Canada are enough to melt a heart of stone. The small-pox is ten times more terrible than Britons, Canadians, and Indians together." John Adams wrote in June elped_win_the_revolutionary_war.html

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17 2017 WHO REPORT 500 cases/100,000 Democratic People s Republic of Korea Lesotho Mozambique Philippines and South Africa.

18 Geographical Distributions of XDR-TB In Summer of 2010, only 45 countries or so. As of end of 2010, up to 68 countries A few years later, 84 countries, according to WHO Worse news 117 countries by % of people with MDR-TB have XDR-TB. India,China and the Russian Federation accounted for 45% of the combined total of cases. WHO TB Report 2015

19 Unthinkable news Specter of Totally Drug Resistant TB is indisputable Reported cases in Italy, Iran, Japan, South Africa, US?

20 When can emerging diseases establish? Infectious agents introduced into vulnerable population Cause disease Spread readily between person-toperson

21 Where emerging diseases come from? Zoonotic 75% of the time Acquired resistance Climate change

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23 Artemisinin Resistance Cambodia, the Lao People s Democratic Republic, Myanmar, Thailand and Viet Nam. Aedes aegypti These mosquitoes live in tropical, subtropical, and in some temperate climates. They are the main type of mosquito that spread Zika, dengue, chikungunya, and other viruses. Because Ae. aegypti mosquitoes live near and prefer to feed on people, they are more likely to spread these viruses than other types of mosquitoes

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27 Other contributing factors Population growth Migration from rural areas to cities International air travel Poverty and wars Destructive ecological changes due to economic development and land use.

28 Global Health Security International Health Regulations CDC s global programs address over 400 diseases, health threats, and conditions that are major causes of death, disease, and disability. Only 1/3 of nations has capability How is our surveillance? CDC has 10 global disease detection centers in the world. Tracks 300 infectious disease outbreaks in 145 countries Only 30% of countries are able to prevent, detect and respond to outbreaks. althprotection/ghs/ihr/index.html

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30 IHR implementation include the Depts of Agriculture, Commerce, DOD, DOE, Department of Homeland Security, DOJ, State, Treasury, Transportation, VA, EPA, Joint Chiefs of Staff, Nuclear Regulatory Commission, Office of Management and Budget, Office of Science and Technology Policy, USAID, CIA, Post Service U.S. government agencies have just 48 hours to assess the situation after learning about a public health emergency of international concern (PHEIC).

31 IHR require that all countries Detect: Potential threats Assess: Work together with other countries to make decisions in public health emergencies Report: Report specific diseases, plus any potential international public health emergencies Respond: Respond to public health events Public Health Emergency of international concern (PHEIC). PHEIC is declared by the WHO if the situation meets 2 of 4 criteria Is the public health impact of the event serious? Is the event unusual or unexpected? Is there a significant risk of international spread? Is there a significant risk of international travel or trade restrictions? 6

32 Requirements for WHO member country Once a identifies an event of concern, must assess the public health risks of the event within 48 hours. The country must report the information to WHO within 24 hours. Smallpox Always Notifiable Poliomyelitis due to wild-type poliovirus Human influenza caused by a new subtype Severe acute respiratory syndrome (SARS)

33 Four PHEICs since 2007 H1N1 influenza (2009) Polio( x.htm) (2014) Ebola( a/index.html) (2014) Zika virus( x.html) (2016) What can we do at our hospital level?

34 Lessons learned from previous outbreaks H5N1 SARS MERS EBOLA ZIKA

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36 Superspreader Phenomenon

37 Early works on Super-spreader? Riley et al. 1960s 4% pts produced 77% of infections 13% pts for all transmissions Van Geuns et al Only 28% of smear + pts are infectious David R. Park, M.D. TB Transmission and Pathogenesis Presentation from Curry TB Center UCSF Who is a superspreader? Increased strain virulence? Higher pathogen shedding? And differences in the host pathogen relationship?

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45 Lessons Learned Early and rapid detection of suspected infected patients Good infection control Education National and global preparedness guidelines

46 Case study of smallpox as possible bioterrorism In February 1972 in Yugoslavia, a previously vaccinated pilgrim returning from Mecca developed undiagnosed febrile disease 11 relatives and friends with high fever and rash Smallpox and Bioterrorism BY TOYIN AJAYI

47 Exploding epidemic A school teacher quickly became critically ill with the rare hemorrhagic form Given penicillin at a local hospital Transferred to a dermatology ward Finally to a critical care unit because of bleeding profusely and in shock Died 2 days before first cases recognized Final Contact Investigation First cases were diagnosed 4 weeks after the first patient became ill. By then, 150 people were already infected; 38 were infected by the teacher. The outbreak was contained 9 weeks after the first patient became sick. 175 patients contracted smallpox, 35 of whom died.

48 Remember that the conduct of each depends the fate of all. Alexander the Great