A presentation on MERS-CoV, the causative agent of Middle East Respiratory Syndrome, given during the Advanced Virology course at Middle Tennessee State University in October 2015.

1. MERS-CoV: An Overview
Richard Bautista
October 23, 2015

2. Outline
• Characteristics
• Epidemiology
• Transmission
• Clinical Aspects
– Diagnosis
– Treatment
– Prevention

3. Characteristics
• Family: Coronaviridae
• Genus: Betacoronavirus
(βCoV)
• Capsid: Helical, Enveloped
– Pleomorphic
• Genome: ssRNA, + polarity,
~ 30 kb
• Causative agent of Middle
East Respiratory Syndrome
(MERS)

4. “Life” Cycle
• Attachment
– DPP4
• Penetration
– Fusion
• Translation before
replication
– Template: - polarity
RNA
• Assembly
– ER-Golgi
intermediate
compartment
(ERGIC)
• Release
– Exocytosis via
vesicle

5. Epidemiology
• Primarily Middle East
– Esp. Saudi Arabia

6. Epidemiology

7. Epidemiology
• Primarily Middle East
– Esp. Saudi Arabia
(~75%)
• Other countries
– Originated from ME
• Most cases outside
ME: South Korea
– 185 cases, 33 deaths
(5/20/2015-7/7/2015)

8. Epidemiology
• Origin/Reservoir
– Camels

9. Epidemiology
• Origin/Reservoir
– Camels...?

10. Epidemiology
• Origin/Reservoir
– Most likely: Bats

11. Epidemiology
• Secondary Reservoir:
Dromedary camels
• Evidence present in
camels in ME and E.
Africa as early as 1983
• Juvenile camels at higher
risk than adult camels
• Circulating in camels a
long time

12. Epidemiology
Final answer on Origin/Reservoir:
No one knows with certainty.

13. Epidemiology
• Mortality: ~35%
• Primary Cases in Humans
– Most common: Middle-aged males (3.3:1 M:F)
– 62% of cases were severe
– 96% of patients had comorbidities
• Diabetes mellitus
• Chronic renal disease
• Hypertension
– Highest risk profile: Male, >50 yrs, multiple
comorbidities

14. Epidemiology
• Secondary Cases in Humans
– Mostly younger patients
– Health care workers w/o comorbidities
– Nosocomial infections (HCA)
– Household contacts

15. Transmission
• Primary Cases
– Animal-to-human contact
• Secondary Cases
– HCA
– Household contacts
• Respiratory secretions
• Bodily fluids (?)
• Animal meat/milk (?)

16. Transmission
• Incubation: ~5.2 days (1.9-14.7)
• Symptom Onset: ~12.4 days
• Rare: Asymptomatic...viral shedding up to
5 weeks after case contact

17. Clinical Aspects – Diagnosis
• Symptoms
– Most common: Non-
specific
• Fever
• Chills
• Sore throat
• Nonproductive cough
• Shortness-of-breath

18. Clinical Aspects – Diagnosis
• Symptoms
– Severe/Decline
• Acute pneumonia
• High fever
• Tachypnea
• Tachycardia
• Hypotension
• Chest radiograph abnormalities (nonspecific)

19. Clinical Aspects – Diagnosis
• Additional Symptoms
– Gastrointestinal
• Diarrhea
• Nausea
• Vomiting
• Abdominal pain
– Unique Symptom: Renal Failure
• Doesn’t occur in any other CoV

20. Clinical Aspects – Diagnosis
• Laboratory confirmation required
– RT-PCR

21. Clinical Aspects – Treatment
• No effective antiviral
drugs currently
available
• Supportive care

22. Clinical Aspects – Treatment
• Experimental
Approaches
– Testing compounds for
broad-spectrum
antiviral activity
– Comparing existing
drugs for anti-MERS-
CoV activity
– Novel therapies
targeting specific gene
sequences or
molecular structures

23. Clinical Aspects – Prevention
• No vaccine
• Healthcare-setting
– Contact/droplet/airborne precautions
• PPE
– Hygiene/sterilization
• Limit animal contact

24. Questions?

25. Acknowledgements
• Dr. Stephen Wright, Professor
• Department of Biology, Middle Tennessee
State University

26. References
• Chan JFW, Lau SKP, To KKW, Cheng VCC, Woo PCY, Yuen K-Y. 25 March 2015.
Middle East respiratory syndrome coronavirus: another zoonotic betacoronavirus
causing SARS-like disease. Clin Microbiol Rev doi:10.1128/CMR.00102-14.
• Confirmed cases of MERS-CoV. 16 October 2015. World Health Organization.
http://www.who.int/csr/disease/coronavirus_infections/maps-epicurves/en/
• Confirmed cases of Middle East Respiratory Syndrome. (Map). 11 June 2015. World
Health Organization. http://www.who.int/csr/disease/coronavirus_infections/mers-
global-situation-map-2015-06-11.png?ua=1
• Fung TS, Liu DX. 17 June 2014. Coronavirus infection, ER stress, apoptosis, and
innate immunity. Front Microbiol http://dx.doi.org/10.3389/fmicb.2014.00296
• Joshi RM (2013) Middle East Respiratory Syndrome Coronavirus (MERSCoV):
Perceptions, Predictions, Preventions and the Pilgrimage. Clin Microbial 2:e113. doi:
10.4172/2327-5073.1000e113
• Middle East respiratory syndrome coronavirus (MERS-CoV): Summary of current
situation, literature update, and risk assessment. 7 July 2015. World Health
Organization.
http://apps.who.int/iris/bitstream/10665/179184/2/WHO_MERS_RA_15.1_eng.pdf

27. Image Sources
• https://www.pdx.edu/sites/www.pdx.edu.intl/files/M.E.cult.jpg
• http://phil.cdc.gov/PHIL_Images/18115/18115_lores.jpg
• https://michellepetersen76.files.wordpress.com/2014/07/middle-
east-respiratory-syndrome-coronavirus-detected-in-the-air-of-a-
saudi-arabian-camel-barn-healthinnovations.jpg?
w=700&h=280&crop=1
• http://www.lonelyplanet.com/maps/middle-east/map_of_middle-
east.jpg
• http://www.skullsunlimited.com/userfiles/image/dromedary-camel.jpg
• http://www.cidrap.umn.edu/sites/default/files/public/styles/ss_media
_popup/public/media/article/taphozous_perforatus_1.jpg?
itok=TKC3jqch
• http://static.ddmcdn.com/gif/blogs/6a00d8341bf67c53ef016300748e
78970d-800wi.jpg
• http://healthwallpaper.info/wp-content/uploads/2015/03/health-
symbol.jpg