The epidemiology, etiology and disease profile caused by MERS-CoV

1. Middle East Respiratory Syndrome
(MERS)
Presented by:
Gaurav Kamboj
JR, Community Medicine

2. Contents
• Corona Virus
• Middle East Respiratory Syndrome- An Introduction
• Epidemiology and Current status
• Source of Virus
• Transmission and Clinical Presentation
• Laboratory findings
• People who may be at risk to MERS-CoV infection
• Case definitions
• Treatment and Prevention
• Traveler's guidelines
• Status in India
• References

3. Corona Viruses
• Corona viruses are enveloped viruses with
a positive-sense RNA genome and with a
nucleo-capsid of helical symmetry.
• The name "coronavirus" is derived from the
Latin corona, meaning crown or halo.
• Under electron microscopic examination, each
virion is surrounded by a "corona," or halo. This
is due to the presence of viral spike peplomers
emanating from each proteinaceous envelope.

4. • Corona viruses primarily infect the upper
respiratory and gastrointestinal tract of
mammals and birds.
• The most publicized human corona
virus, SARS-CoV which causes SARS, has a
unique pathogenesis because it causes both
upper and lower respiratory tract
infections and can also cause gastroenteritis.
• Corona viruses are believed to cause a
significant percentage of all common colds in
human adults
Corona Viruses

5. Middle East Respiratory Syndrome (MERS-CoV)
• The novel corona virus (MERS-CoV), first detected in April 2012, is a new virus that has not been
seen in humans before.
• This new corona virus is now known as Middle East Respiratory Syndrome Corona Virus
(MERS-CoV).
• Health officials first reported the disease in Saudi Arabia in September 2012.
• Through retrospective investigations, health officials later identified that the first known cases
of MERS occurred in Jordan in April 2012.
• About 3-4 out of every 10 patients reported with MERS have died. (36% - Case fatality rate)
• So far, all cases of MERS have been linked to countries in and near the Arabian Peninsula.
• MERS can affect anyone. MERS patients have ranged in age from younger than 1 to 99 years old

6. MERS-CoV particles as seen by negative stain electron microscopy.
Virions contain characteristic club-like projections emanating from
the viral membrane.

8. 26 Countries reporting MERS cases
>85%

9. Epidemiology
• As of 19 June 2015, 1338 laboratory-confirmed cases of human
infection with MERS-CoV have been reported to WHO since 2012,
including at least 475 deaths.
• Overall, 66% of cases reporting gender (n=1329) are male and the
median age is 50 years (range 9 months–99 years; n=1335)
• During Ramadan, 1 million pilgrims are expected to arrive in Saudi
Arabia in June-July 2015. And MERS remains a threat to global health
security.

13. If it's a 'Middle East' virus, why is it exploding
all the way in Korea?
• It all started with one man. On 20th May 2015, the Republic of Korea notified
WHO of the first laboratory-confirmed case of MERS-CoV.
• The index case had recently travelled to the Kingdom of Saudi Arabia (KSA),
Qatar, the UAE and Bahrain. The source of his infection remains unknown.
• The second case was his wife, the third was his hospital roommate, the fourth
was the daughter of the roommate, the fifth was a healthcare professional who
treated the first patient, and so on.

14. MERS-CoV in Republic of Korea
• According to the WHO, the rapid spread of the disease in South
Korea was because of - among other things - a lack of awareness
among the public and healthcare workers about MERS, crowded
hospitals and emergency rooms, visitation by too many friends and
family members and the practice of 'doctor shopping', or seeking
care in multiple hospitals.
• This is the largest outbreak of MERS outside the Middle East.
• In this outbreak, transmission of MERS-CoV has been strongly
associated with health care settings. 14% cases are health care
professionals

16. Source of the virus
• MERS-CoV is a zoonotic virus that has been transmitted from animals
to humans.
• The origins of the virus are not fully understood but, according to the
analysis of different virus genomes, it is believed that it originated in
bats and was transmitted to Camels sometime in the distant past.

17. Transmission
Transmission from animals to humans
• It is not yet fully understood how people become infected with MERSCoV, which is
a zoonotic virus.
• It is believed that humans can be infected through direct or indirect contact with
infected dromedary camels in the Middle East.
• Strains of MERS-CoV have been identified in camels in several countries, including
Egypt, Oman, Qatar and Saudi Arabia.
• The most critical question remains to be answered, that is, the type of human
exposures that result in infection.
• Most human cases do not have a history of direct contact with camels; if camels
or other animals are the source, the route of transmission to humans may be
indirect.

18. Transmission
Transmission from humans to humans
• The virus does not appear to pass easily from person to person unless there is
close contact such as providing clinical care to an infected patient
• This has been seen among family members, patients, and health‐care workers.
• Undetermined Droplet and direct contact probably Large droplet transmission is
suspected as the most likely route.
• Majority cases have resulted from human to human transmission in health care
settings.
• All reported cases have been linked to countries in and near the Arabian
Peninsula.

19. Symptoms & Complications
• Most people confirmed to have MERS-CoV infection have had severe acute
respiratory illness with symptoms of fever (38°C , 100.4°F), cough and shortness
of breath
• Gastrointestinal symptoms including diarrhea and nausea/vomiting.
• More severe complications, such as pneumonia and kidney failure in many cases.
• About 3-4 out of every 10 people reported with MERS have died. Most of the
people who died had an underlying co-morbid medical condition.
• Some infected people had mild symptoms (such as cold-like symptoms) or no
symptoms at all; they recovered.
• People with pre-existing medical conditions (like diabetes; cancer; and chronic
lung, heart, and kidney disease) or weakened immune systems may be more
likely to become infected with MERS-CoV, or have a severe case.

20. Clinical Presentation
• A wide clinical spectrum of MERS-CoV infection has been reported ranging from
asymptomatic infection to acute upper respiratory illness, and rapidly progressive
pneumonitis, respiratory failure, septic shock and multi-organ failure resulting in death.
• Most MERS-CoV cases have been reported in adults (median age approx. 50 years, male
predominance), although children and adults of all ages have been infected (range 9 months
to 99 years).
• At hospital admission, common signs and symptoms include fever, chills/rigors, headache,
non-productive cough, dyspnea, and myalgia.
• Pulmonary parenchymal disease (e.g., pneumonia or acute respiratory distress syndrome
based on clinical or radiological evidence of consolidation) is found in most patients
• Other symptoms can include sore throat, coryza, nausea and vomiting, dizziness, sputum
production, diarrhea, vomiting, and abdominal pain.

21. Clinical Course
• The median Incubation period is usually about 5 or 6 days (range 2-14 days) and
the median time from onset of illness to hospitalization is approx. 4 days.
• In critically ill patients, the median time from onset to ICU admission is approx. 5
days, and median time from onset to death is approximately 12 days.
• Radiographic findings may include unilateral or bilateral patchy densities or
opacities, interstitial infiltrates, consolidation, and pleural effusions.
• Rapid progression to acute respiratory failure, acute respiratory distress
syndrome (ARDS), refractory hypoxemia, and extra-pulmonary complications (like
acute kidney injury requiring renal replacement therapy, hypotension requiring
vasopressors, hepatic inflammation, septic shock) has been reported.

22. Laboratory Testing
• Novel Coronavirus 2012 Real-time PCR Assay (NCV-12 rRT-PCR Assay) is used to
conform MERS-CoV in respiratory, blood and stool samples.
• To increase the likelihood of detecting MERS-CoV infection, CDC recommends
collecting multiple specimens from different sites at different times after
symptom onset.
• CDC strongly recommends testing a lower respiratory specimen (e.g., sputum,
broncho-alveolar lavage fluid, or tracheal aspirate), a naso/oropharyngeal swab,
and serum.
• Stool specimens are of lower priority
• If symptom onset was more than 14 days prior, CDC also strongly recommends
additional testing of a serum specimen via the CDC MERS-CoV serologic assay.

23. Laboratory Findings
Laboratory findings at admission may include:
• Leukopenia, lymphopenia, thrombocytopenia, and elevated
lactate dehydrogenase levels.
• Co-infection with other respiratory viruses and community-
acquired bacteria has been reported
• Nosocomial bacterial and fungal infections have been
reported in mechanically-ventilated patients.
• MERS-CoV virus can be detected with higher viral load and
longer duration in the lower respiratory tract compared to
the upper respiratory tract, and has been detected in feces,
serum, and urine.
• However, very limited data are available on the duration of
respiratory and extra-pulmonary MERS-CoV shedding.

24. People Who May Be at Increased Risk for
MERS
• Recent Travellers from the Arabian Peninsula
• Develop fever and symptoms of respiratory illness, such as cough or shortness
of breath, within 14 days after traveling from countries in or near the Arabian
Peninsula
• Close Contacts of an Ill Traveller from the Arabian Peninsula
• Close contact with someone within 14 days after they travelled from a
country in or near the Arabian Peninsula, and the traveller has/had fever and
symptoms of respiratory illness, such as cough or shortness of breath, health
should be monitored for 14 days, starting from the day last exposed to the ill
person.

25. People Who May Be at Increased Risk for
MERS
• People recently in a healthcare facility
• Develop a fever and symptoms of respiratory illness, such as cough or
shortness of breath, within 14 days after being in a healthcare facility (as a
patient, worker, or visitor) situated in the affected country
• Close Contacts of a Confirmed Case of MERS
• Monitor health for 14 days, starting from the day last exposed to the ill
person. Watch for these symptoms:
• Fever. Take temperature twice a day.
• Coughing
• Shortness of breath
• Other early symptoms to watch for are chills, body aches, sore throat,
headache, diarrhea, nausea/vomiting, and runny nose.

26. People Who May Be at Increased Risk for
MERS
• Healthcare Personnel not using recommended Infection-Control
Precautions
• People with Exposure to Camels
• The WHO has posted a general precaution for anyone visiting farms, markets,
barns, or other places where animals are present.
• Travellers should practice general hygiene measures, including regular
handwashing before and after touching animals, and avoid contact with sick
animals.
• Travellers should also avoid consumption of raw or undercooked animal
products (milk, urine, meat).
• High risk groups for severe MERS
• People with diabetes, kidney failure, or chronic lung disease and people who
have weakened immune systems

27. ‘Patient Under Investigation’ (PUI)
A person who has both clinical features and an epidemiologic risk should be considered
a patient under investigation (PUI) based on one of the following scenarios:
• Fever AND pneumonia or acute respiratory distress syndrome (based on clinical or
radiologic evidence) AND EITHER:
• history of travel from countries in or near the Arabian Peninsula within 14 days before symptom onset, OR
• close contact with a symptomatic traveller from countries in or near the Arabian Peninsula, OR
• history of being in a healthcare facility (as a patient, worker, or visitor) within 14 days before symptom onset,
OR
• a member of a cluster of patients with severe acute respiratory illness (e.g., fever and pneumonia requiring
hospitalization) of unknown etiology in which MERS-CoV is being evaluated
OR
• Fever OR symptoms of respiratory illness (not necessarily pneumonia) AND close
contact with a confirmed MERS case while the case was ill.

28. Close Contact
a) Being within approximately 6 feet (2 meters) or within the room or
care area for a prolonged period of time (e.g., healthcare personnel,
household members) while not wearing recommended personal
protective equipment (i.e., gowns, gloves, respirator, eye protection)
b) Having direct contact with infectious secretions (e.g., being coughed
on) while not wearing recommended personal protective equipment
(i.e., gowns, gloves, respirator, eye.).
c) Any person who stayed at the same place (e.g. lived with, visited) as
the patient while the patient was ill.

29. Probable Case
• A PUI having evidence of pulmonary parenchyma disease (e.g.
pneumonia or ARDS) with absent or inconclusive laboratory results
for MERS-CoV infection who is a close contact of a laboratory-
confirmed MERS-CoV case.
• Any person with severe acute respiratory illness with unknown
aetiology
• An epidemiologic link to a confirmed MERS case.

30. Confirmed Case
• A confirmed case is a person with laboratory confirmation of MERS-
CoV infection.
• A case can be confirmed by the demonstration of sero-conversion in 2
samples ideally taken at least 14 days apart, by a screening (ELISA,
IFA) and a neutralization assay.

31. Treatment
• There is no specific antiviral treatment recommended for MERS-CoV
infection.
• Individuals with MERS can seek medical care to help relieve
symptoms.
• For severe cases, current treatment includes care to support vital
organ functions.
• Any additional benefit of novel pharmacological agents remains
uncertain.

32. Agents which can be used:
• Convalescent plasma
• Interferon
• Protease Inhibitors
• Intravenous Immunoglobulin
• Nitazoxanide
• Cyclosporin A
• Ribavirin
• Corticosteroids
• Interferon plus ribavirin

33. Prevention
• Because neither the source of the virus nor the mode of transmission is
known, it is not possible to give specific advice on prevention of infection
• CDC routinely advises that people help protect themselves from respiratory
illnesses by taking everyday preventive actions:
• Wash hands often with soap and water for 20 seconds, and help young children do
the same. If soap and water are not available, use an alcohol-based hand sanitizer.
• Cover nose and mouth with a tissue when cough or sneeze, then throw the tissue in
the trash.
• Avoid touching eyes, nose and mouth with unwashed hands.
• Avoid personal contact, such as kissing, or sharing cups or eating utensils, with sick
people.
• Clean and disinfect frequently touched surfaces and objects, such as doorknobs.

34. PREVENTION

35. Prevention
• Contact with any obviously sick animals
(including birds) should be avoided
• Sick animals should never be slaughtered
for consumption.
• The consumption of raw or undercooked animal products, including milk
and meat, carries a high risk of infection from a variety of organisms that
might cause disease in humans.
• Dishes, drinking glasses, cups, eating utensils, towels, bedding, or other
items should not be shared with a person who is confirmed to have, or
being evaluated for MERS-CoV infection.

36. MERS-CoV Vaccine
• Currently, there is no vaccine to prevent MERS-CoV infection
• Novavax on June 6, 2013 announced that it has successfully produced a
vaccine candidate designed to provide protection against the recently
emerging Middle East Respiratory Syndrome Coronavirus (MERS-CoV).
• The vaccine candidate was made using Novavax’ nanoparticle vaccine
technology, and is based on the major surface spike (S) protein.
• The development of a MERS vaccine candidate currently remains a pre-
clinical program

37. Personal protective equipment and
procedures
• Non-sterile patient-care gloves
• Disposable isolation gowns
• Goggles or face shield
• Fit-tested, disposable respirators (at least
as protective as fit-tested NIOSH-certified
disposable N95 filtering facepiece
respirators)
• Hand hygiene product (e.g., alcohol-based
hand rub)
Upon exit from the patient room or care area,
PPE should be removed and either discarded, or
for re-useable PPE, cleaned and disinfected

38. Traveler's guidelines
• CDC recommends that travellers to countries in or near the Arabian
Peninsula may pay attention to their health during and after their trip.
• Travellers should see a doctor right away if they develop fever and
symptoms of lower respiratory illness, such as cough or shortness of
breath, within 14 days after travelling from countries in or near the
Arabian Peninsula.
• They should tell the doctor about their recent travel.

39. Traveler's guidelines
• CDC does not recommend that
most travelers change their plans
because of MERS.
• However, the Saudi Arabia Ministry
of Health has made special
recommendations for travellers to
Hajj and Umrah.

40. WHO-SEAR calls for stepping up vigil for MERS,
Thialand confirms case
• On 18th June 2015, Thailand confirmed MERS
CoV disease in a traveler from Middle East
region, the first case in WHO South East Asia
Region
• Considering the high volume of tourist traffic
between India and Thailand, and with the
Hajj pilgrimage approaching in mid-
September, it makes sense to be vigilant
about MERS in India.
• More than 1,36,000 Indians are expected to make the pilgrimage to Mecca this
year, and Thailand registered 9,46,269 Indian tourists last year. Any one of these
visitors could be a potential carrier of MERS to India.

41. Response to MERS in India
• An alert has been sounded at all airports to screen passengers
especially from Middle East and South Korea for Middle East Corona
Virus (MERS-CoV)
• Airports throughout the country have been asked to report any
passengers who are self-reporting at immigration counters with
symptoms of fever and respiratory distress.
• Flights coming from the 26 affected countries have been asked to
make an in-flight announcement asking passengers complaining of
fever, cough or respiratory distress to report to medical unit at the
airport.

42. References
• http://www.cdc.gov.in/merscoronavirus
• www.who.int/coronavirus/mers
• http://www.who.int/emergencies/mers-cov/en
• WHO guidelines on infection prevention and control during health
care for probable or confirmed cases of novel coronavirus (nCoV)
infection
• B Guery et al. Clinical features and viral diagnosis of two cases of
infection with Middle East Respiratory Syndrome coronavirus: a
report of nosocomial transmission. Lancet (2013).
• K. Park “Textbook of Preventive and Social Medicine” 22 edition