Viruses in The News: Ebola, Influenza and Enterovirus 68 - Todd F Hatchette MD FRCPC Division Head and Service Chief Microbiology, DPLM, CDHA ...
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Viruses in The News:
Ebola, Influenza and
Enterovirus 68
Todd F Hatchette MD FRCPC
Division Head and Service Chief
Microbiology, DPLM, CDHA
October 2, 2014
Outline
• Ebola • What is it and where did it
• Influenza come from
• Enterovirus 68 • How do Humans Get it?
• What is the Current Situation
and what Does the Future
Hold?
• Are We Prepared?
• How do you protect yourself
What is Ebola? Where did it Come From? How do Humans Get it?
What is Ebola
1) Marburg virus
2) Ebola Zaire
3) Ebola Sudan
Source: CDC 4) Ebola Ivory Coast
5) Ebola Reston
6) Ebola Bundibugyo
http://viralzone.expasy.org/all_by_species/23.ht
ml
History http://www.bloomberg.com/news/2014-08-29/
Where Does The Virus Come From
http://elitedaily.com/news/world/ebola-traced-back-
fruit-bat/725153/
http://www.thetimes.co.uk/tto/news/world/africa
source: cdc.gov /article4054794.ece
How are humans infected Source: cdc.gov
How are Humans Infected
• Bats have high titrs in
feces
• Used as food
http://squathole.wordpress.com/2014/03/28
• Bush meat trade alive
/sorry-bats-off/
and well
Photo: WSPA/K.AMMANN / REX
http://www.telegraph.co.uk/health/healthnews/11006343/Ebola-
crisis-why-is-there-bush-meat-in-the-UK.html
How are Humans Infected
• direct contact with
– blood or secretions
– Urine,
– feces,
– semen,
– breast milk
• exposure to objects
that have been
contaminated with
infected secretions.
• Mucosal surface /
breaks in skin /
parentral
Ways it is NOT Transmitted • Animal data to suggest aerosol transmission is possible but not seen in the field • Patients DO NOT transmit when asymptomatic.
What is the Current Situation?
Current Situation
(map as of Sept 6)
Started March 2014
http://www.nejm.org/action/showMedia
Player?doi=10.1056%2FNEJMoa14111
00&aid=NEJMoa1411100_attach_1&ar
ea=aopWHO Update - (Sept 26, 2014)
Country Case Deaths
(confirmed/prob/susp)
Guinea 1074 648 (60%)
Liberia 3458 1830 (53%)
Sierra Leone 2021 605 (30%)
Nigeria 20 8 (40%)
Senegal 1 0
Total 6574 3091 (47%)
Dem Rep Congo 70 42 (60%)Symptoms of the Current Outbreak
(NEJM; September 23, 2014)
Presentation is non-specific
• Fever – 87% • Incubation period 2-21 days
• Fatigue – 76% (ave 11 days)
• Loss of appetite – 65% • Serial interval 15 days
• Vomiting – 68%
• Diarrhea – 66%
• conjunctival injection – 21%
• Unexplained Bleeding –18%
• Rash – 6%
• Cough not common - 30%EARLY LATE DEATH OR RECOVERY http://cdn.zmescience.com/wp-content/uploads/2014/08/ebola_outbreak.jpg Death from Hypovolemic shock and Multiorgan failure - 6-16 days
What Is The Natural History of Ebola Virus
Infection In Humans?
• Nonfatal cases
– fever for 5-9 days and then improve
– coincident with humoral antibody response
– Complete recover can take weeks
• Weakness / arthralgias / headaches / hairloss
• Mortality: 30 -90%
• Death occurs 4 days from hospitalization
– NEJM 2014
• Current outbreak is approx 54%How does it kill
• Cytokine storm
• Capillary leakage
• Direct endothelial
damage
http://o.canada.com/news/africas-ebola-outbreak-
the-worst-crisis-weve-ever-hadPatient Management
CCCS / CSEP / AMMI guidelines
• Protect HCW
• Minimize testing
• Rule out other common
infections
• Supportive care
• Point of care equipment
http://www.ammi.ca/media/69846/Ebola%
20Clinical%20Care%20Guidelines%202%
20Sep%202014.pdfHow Can HCW protect themselves
• Use the appropriate PPE – contact and droplet
– N95 for aerosol generating procedures
www.pathogenperspectives.com
www.cdc.govWhy Are HCWs being Infected http://rt.com/news/ebola-virus-outbreak-guinea-941/
Are We Prepared? http://www.marciliroff.com/new/be-prepared/
Screening Tool • Present with fever > 38.6 and other symptoms • Travel to one of the affected regions in th least 21 days – Probe a little more can stratify risk • 811 / EHS / ED all aware and will use to determine if potential case • Notify MOH – trigger a teleconference – ID / Micro /EHS
What is the NS Plan • CDHA / IWK will be site for clinical assessment • Medical Officer of Health coordinates • Dedicated equipment • Visitor restriction • Dedicated HCWs
What Does the Future Hold?
The Risk to NS is Low Gomes et al., PLOS current outbreaks Sept 2014
Predictions.
Where Are We Headed
Source: WHO Sept 12, 2014
Source: Science: Aug 31 2014
• Estimated Ro
– 1.7 – 2.02
• Estimated doubling
time – 15 – 30 daysPredictions?
Source: based on WHO data
http://www.abovetopsecret.com
/forum/thread1025400/pg1
• Based on WHO models (NEJM Sept 25)
• By Nov 2 – over 20,000 cases:
– 5740 Guinea / 9890 Liberia / 5000 Sierra LeoneHow Do We Stop It?
This is NOT an African Problem
It Is A Global Problem
• Early diagnosis
• Contact tracing
• Isolation
• Infection Prevention
and Control
• Safe burial practices
http://www.directrelief.org/tag/2014-west-africa-ebola-
outbreak/What treatment/prevention optins
are on the horizon
• Convalescent serum
• ZMAPP Source: CBC.ca
– Humanized
monoclonal
antibodies
• Novel vaccines
• Novel antivirals
– TKM
Fukijilm Holdings / Associated Press
http://www.usnews.com/news/articles/2014/09
/02/ebola-vaccine-trials-to-begin-this-weekWhat is Influenza and Where Does it Come From?
The Virus 18 HA ; 11 NA subtypes
Influenza Dogma
• Feral aquatic
birds are natural
host
• “evolutionary
stasis” in natural H1N1
host H3N2
• Evolve quickly
when cross
H1N1
species High path.
Low path. H3N2“Pandemic Influenza”
• An outbreak of influenza infection that spreads
throughout the world.
• Requirements:
– Must be able to readily infect humans.
– Novel strain to which the population lacks immunity:
• A high percentage of individuals are infected resulting in increased
mortality rates.
– Readily transmissible between hosts:
• Spread by respiratory secretions in the form of droplets expelled
during coughing or sneezing.Generation of Pandemic Influenza
“Antigenic Shift”PB2
PB1
PA
HA
NP
NA
M
NS
H1N1 H2N2 H3N2 pH1N1
1918 lineage 1957-1958 1968 – 1969 2009 - present
20 million worldwide “Asian Flu” “Hong Kong flu” “swine flu”
(550,000 US) 1 million worldwide 1 million worldwide
(70,000 US) (34,000 US)
2009
1957 1968 1977
H1N1
H3N2
H2N2 H1N2
H1N1
H1N1
1918 1950 1960 1970 1980 1990 2000 2010Why Does the Seasonal Influenza Vaccine Change Every Year?
Immune System Forces
“Antigenic Drift”
Mutation
Globe and Mail; Oct. 19 2012Catch me if you can
Transmission - Person to person • Droplet spread – Influenza • Contaminated fingers/hands • Fomites (Objects) • Aerosol is controversial
Treatment
Neuraminidase Inhibitors
Amantidine
(NAI)
Moscona. 2005. NEJM. 353:1363
Nature reviewsHow To Protect Yourself and Others Prevent Infection Prevent Transmission
The Influenza Vaccine
It is Safe and Effective!
• Most effective in <
65yrs
• Reduces hospitalization
and death in elderly
• Serious side effects are
rare
The best protection against annual flu is
vaccinationWhat other “Flus” are out there
vH3N2
H7N9Enterovirus 68
Enterovirus 68
• First isolated in California in
1962 from four children with
bronchiolitis and pneumonia
CNN.com
• 79 cases from 2009 – 2013 in
US
• 82 cases in Canada since 1999
• type D enteroviruses and is
almost exclusively respiratoryWhat are the symptoms
• Mild to severe respiratory illness.
• Most have mild symptoms
– fever, runny nose, sneezing, cough, and body and
muscle aches.
• Severe symptoms can occur in asthmatics,
immune comprimised, very young
– Parents should seek immediate medical attention
if their children have trouble breathing and
children not eating
• Can be seen in adults (25% of cases in
previous outbreaks)Closely Related to Rhinovirus
(common cold)
EV68It is Wide Spread at the Moment
• 472 cases in US
• 41 States
• BC / Alberta
• Potential underestimate because of challenges
with detectionHow Is it Spread • Respiratory Secretions • Oral secretions • Stool – “fecal oral route” • Enterovirus season is commonly in the fall
How can I protect myself? • Wash hands often • Avoid touching eyes, nose and mouth. • Avoid kissing, hugging, and sharing cups or utensils with sick. • Disinfect frequently touched surfaces, especially if someone is sick.
What if Your Child Has Asthma • They are higher risk for respiratory illnesses in general – regularly take medicines to control asthma – Get your influenza vaccine – Watch for unusual respiratory distress with a cold
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