“Understanding and Preparing for Emerging

Disease Outbreaks”

CAPT Ha C. Tang, D.O. US Public Health ServiceAdjunct Associate Clinical Professor of Dartmouth Medical School,

Community/Family Medicine Dept.Deputy Chief of Family Medicine Department

Disclosures: None

Co-authors:

Reasol A. Chino, PharmD, BCACPCommander, US Public Health ServiceAssistant Director of Pharmacy Tuba City Regional Health Care Corp(TCRHCC)

Paul Chefor, PharmD, BCACPLT Commander, US Public Health ServiceDirector of inpatient Pharmacy Tuba City Regional Health Care Corp(TCRHCC

Sita Marie Shablack, PharmDLT, US Public Health Service Advance Practice Pharmacist ITuba City Regional Health Care Corp(TCRHCC

Objectives

Understand history and threats of emerging diseases.

What are the likely emerging diseases of the 21St 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

“Forethought we may have, undoubtedly, but

not foresight.”Napoleon Bonaparte

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

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.

https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/emerging-infectious-diseases

“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 2014” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547580/

Risk to HCP from Emerging Diseases

Middle East respiratory syndrome coronavirus MERS at 1–27%,

Ebola 2.5–12%, SARS 11–57%

“Risks to healthcare workers with emerging diseases: lessons from MERS-CoV, Ebola, SARS, and avian flu,” by Suwantarat, Nuntraa,b; Apisarnthanarak, Anucha in Current Opinion in Infectious Diseases- : August 2015 - Volume 28 - Issue 4 - p 349–361

Most notable infectious diseases of the centuries

Plague Smallpox Tuberculosis

Plague

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

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

http://www.sciencemag.org/news/2014/07/six-vials-smallpox-discovered-us-lab

"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 1776

https://www.realclearscience.com/blog/2016/09/how_vaccination_helped_win_the_revolutionary_war.html

2017 WHO REPORT

500 cases/100,000• Democratic People’s Republic of Korea • Lesotho • Mozambique• Philippines and South Africa.

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 2015. 9.7% of people with MDR-TB have

XDR-TB. India,China and the Russian

Federation accounted for 45% of the combined total of 580 000 cases.

WHO TB Report 2015

Unthinkable news

Specter of Totally Drug Resistant TB is indisputable

Reported cases in Italy, Iran, Japan, South Africa, US?

When can emerging diseases establish?

Infectious agents introduced into vulnerable population

Cause disease Spread readily between person-to-

person

Where “emerging diseases” come from?

Zoonotic 75% of the time Acquired resistance Climate change

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

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.

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.

https://www.cdc.gov/globalhealth/healthprotection/ghs/ihr/index.html

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).

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

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.

Always Notifiable

Smallpox Poliomyelitis due to wild-type

poliovirus Human influenza caused by a new

subtype Severe acute respiratory syndrome

(SARS)

Four PHEICs since 2007

H1N1 influenza (2009) Polio(https://www.cdc.gov/polio/inde

x.htm) (2014) Ebola(https://www.cdc.gov/vhf/ebol

a/index.html) (2014) Zika

virus(https://www.cdc.gov/zika/index.html) (2016)

What can we do at our hospital level?

Lessons learned from previous outbreaks

H5N1 SARS MERS EBOLA ZIKA

“Superspreader” Phenomenon

Early works on Super-spreader?

Riley et al. 1960s• 4% pts produced 77% of infections• 13% pts for all transmissions

Van Geuns et al. 1975• 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?

Lessons Learned

Early and rapid detection of suspected infected patients

Good infection control Education National and global preparedness

guidelines

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 HTTPS://WEB.STANFORD.EDU/GROUP/SJIR/3.2.02_AJAYI.HTML

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.

“Remember that the conduct of each

depends the fate of all.”

Alexander the Great