Transcript The disease

MERS-CoV: the disease
Republic of Lebanon
Ministry of Public Health
Epidemiological Surveillance Program
May 2014
Sources
• WHO: www.who.int
• CDC: www.cdc.gov
• ECDC: www.ecdc.europa.eu
Outline
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Appellation
First cases
Reservoir
Modes of transmission
Incubation period
Clinical presentation
Case management
Appellation
• Scientific appellation: The Middle East Respiratory
Syndrome Coronavirus (MERS-CoV)
• By the Coronavirus Study Group of the International
Committee on Taxonomy of Viruses
• Reference: De Groot RJ, et al. Middle East Respiratory
Syndrome Coronavirus (MERS-CoV): Announcement of
the Coronavirus Study Group. J Virol. Published ahead
of print 15 May 2013. doi:10.1128/JVI.01244-13.
Classical coronavirus
• Coronaviruses
– Large family of viruses that cause a range of
illnesses in humans
– Viruses also cause a number of animal diseases
– In Humans:
• Usually: common cold
• Rarely, severe diseases as:
–Severe Acute Respiratory Syndrome (SARS)
–MERS-CoV
First cases
• On 22 September 2012, the UK informed WHO of a case of acute
respiratory syndrome with renal failure with travel history to Saudi Arabia
and Qatar.
• The case: previously healthy, 49 year-old male, Qatari, with travel history
to Saudi Arabia,
– On 3 September: presented symptoms
– On 7 September: admission to ICU in Doha, Qatar
– On 11 September: transfer to UK (by air ambulance). The Health
Protection Agency of the UK (HPA) confirmed the presence of a novel
coronavirus
• The HPA compared the clinical sample with a virus sequenced previously
by the Erasmus University Medical Centre, Netherlands:
– Isolate obtained from lung tissue of a fatal case earlier this year in a 60
year-old Saudi national
– This comparison indicated 99.5% identity, with one nucleotide
mismatch over the regions compared.
Jordan cluster
• On 30 November 2012: two cases from Jordan were
added.
• The fatal cases occurred in April 2012. At that time, a
number of severe pneumonia cases occurred in the
country – cluster in hospital setting.
• On 24 April 2012: samples had tested negative for
known coronaviruses and other respiratory viruses.
• In October 2012: stored samples from the cluster of
April 2012 were sent by MOH Jordan to NAMRU-3.
• In November 2012: NAMRU-3 confirmed two cases of
infection with the novel coronavirus.
Reservoir
• The full picture on the source is not yet clear.
– Camels:
• Camels are a likely source of infection in humans.
• Strains of MERS‐CoV in camels across Africa and the
Middle East.
• Human and camel genetic sequence data demonstrate
a close link between the virus found in camels and that
found in people.
– Other reservoirs may exist.
Modes of transmission
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Different modes of transmission are occurring
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Zoonotic transmission from animals, camels, to humans
 Thus far: primary cases have steadily been reported since April 2013
with recent increase in March and April 2014
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Human-to-human transmission:
• Very little human-to-human transmission is occurring among family
members in household settings
• Nosocomial transmission is occurring health care workers and between
patients resulting in large health care setting outbreaks
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Transmission via environmental or fomite contamination
 Experimental studies of virus persistence on surfaces and at different
environmental conditions show that MERS-CoV can be transmitted via
contact or fomite
Source: WHO
Incubation period
• Usually 5 days
• Range: 2-14 days
Source: Hospital Outbreak of Middle East Respiratory
SyndromeCoronavirus - n engl j med 369;5 nejm.org
august 1, 2013
Symptoms
• A typical case of MERS consists of
– Acute respiratory infection:
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Fever
Cough
Shortness of breath / Dyspnea
Pneumonia is a common finding on examination
– Gastrointestinal symptoms: diarrhoea may be reported
– Severe illness:
• Respiratory failure requiring mechanical ventilation and support in
intensive‐care unit.
• Organ failure: renal failure, septic shock.
– Approximately 27% of patients with MERS have died.
– More severe disease is observed in people with weakened
immune systems, older people, and those with such
chronic diseases as diabetes, cancer, and chronic lung
disease.
Symptoms
Source: Epidemiological, demographic, and clinical characteristics of 47 cases of Middle East respiratory syndrome
coronavirus disease from Saudi Arabia: a descriptive study. Abdullah Assiri MD,Jaffar A Al-Tawfiq FACP,Abdullah A AlRabeeah FRCS,Fahad A Al-Rabiah MD,Sami Al-Hajjar MD,Ali Al-Barrak MD,Hesham Flemban MD,Wafa N Al-Nassir MD,Hanan
H Balkhy MD,Rafat F Al-Hakeem MD,Hatem Q Makhdoom PhD,Prof Alimuddin I Zumla FRCP,Prof Ziad A Memish FRCP. The
Lancet Infectious Diseases - 1 September 2013 ( Vol. 13, Issue 9, Pages 752-761 ). DOI: 10.1016/S1473-3099(13)70204-4
Para-clinical tests
Source: Epidemiological, demographic, and clinical characteristics of 47 cases of Middle East respiratory syndrome
coronavirus disease from Saudi Arabia: a descriptive study. Abdullah Assiri MD,Jaffar A Al-Tawfiq FACP,Abdullah A AlRabeeah FRCS,Fahad A Al-Rabiah MD,Sami Al-Hajjar MD,Ali Al-Barrak MD,Hesham Flemban MD,Wafa N Al-Nassir MD,Hanan
H Balkhy MD,Rafat F Al-Hakeem MD,Hatem Q Makhdoom PhD,Prof Alimuddin I Zumla FRCP,Prof Ziad A Memish FRCP. The
Lancet Infectious Diseases - 1 September 2013 ( Vol. 13, Issue 9, Pages 752-761 ). DOI: 10.1016/S1473-3099(13)70204-4
Underlying medical conditions
Source: Epidemiological, demographic, and clinical characteristics of 47 cases of Middle East respiratory syndrome
coronavirus disease from Saudi Arabia: a descriptive study. Abdullah Assiri MD,Jaffar A Al-Tawfiq FACP,Abdullah A AlRabeeah FRCS,Fahad A Al-Rabiah MD,Sami Al-Hajjar MD,Ali Al-Barrak MD,Hesham Flemban MD,Wafa N Al-Nassir MD,Hanan
H Balkhy MD,Rafat F Al-Hakeem MD,Hatem Q Makhdoom PhD,Prof Alimuddin I Zumla FRCP,Prof Ziad A Memish FRCP. The
Lancet Infectious Diseases - 1 September 2013 ( Vol. 13, Issue 9, Pages 752-761 ). DOI: 10.1016/S1473-3099(13)70204-4
Pulmonary picture
Source: Family Cluster of Middle East Respiratory Syndrome Coronavirus Infections.
Ziad A. Memish, M.D., Alimuddin I. Zumla, M.D., Ph.D., Rafat F. Al-Hakeem, M.D.,
Abdullah A. Al-Rabeeah, M.D., and Gwen M. Stephens, M.D.
Example of case
Source: Family Cluster of Middle East Respiratory Syndrome Coronavirus Infections.
Ziad A. Memish, M.D., Alimuddin I. Zumla, M.D., Ph.D., Rafat F. Al-Hakeem, M.D., Abdullah A. Al-Rabeeah,
M.D., and Gwen M. Stephens. n engl j med 368;26 nejm.org june 27, 2013
Example of case
Source: Family Cluster of Middle East
Respiratory Syndrome Coronavirus
Infections.
Ziad A. Memish, M.D., Alimuddin I.
Zumla, M.D., Ph.D., Rafat F. Al-Hakeem,
M.D., Abdullah A. Al-Rabeeah, M.D.,
and Gwen M. Stephens.
n engl j med 368;26 nejm.org june 27,
2013
Case management:
Early recognition and management
1.
Recognize severe manifestations of acute respiratory infections
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Initiate infection prevention and control measures
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Give supplemental oxygen therapy to patients with SARI
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Collect respiratory and other specimens for laboratory testing
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Give empiric antimicrobials to treat suspected pathogens,
including community-acquired pathogens
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Use conservative fluid management in patients with SARI when
there is no evidence of shock
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Closely monitor patients with SARI for signs of clinical
deterioration, such as severe respiratory distress/respiratory
failure or tissue hypoperfusion/shock, and apply supportive care
interventions
Source: WHO
Case management:
Management of severe respiratory distress,
hypoxemia and ARDS
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Recognize severe cases, when severe respiratory distress may not be sufficiently
treated by oxygen alone, even when administered at high flow rates
Wherever available, and when staff members are trained, mechanical ventilation
should be instituted early in patients with increased work of breathing or
hypoxemia that persists despite high-flow oxygen therapy
Consider NIV if local expertise is available, when immunosuppression is also
present, or in cases of mild ARDS without impaired consciousness or
cardiovascular failure
If equipment is available and staff are trained, proceed with endotracheal
intubation to deliver invasive mechanical ventilation
Use a lung-protective ventilation strategy (LPV) for patients with ARDS
In patients with severe ARDS, consider adjunctive therapeutics early, especially if
failing to reach LPV targets
Use a conservative fluid management strategy for ARDS patients who are not in
shock to shorten the duration of mechanical ventilation (18)
Source: WHO
Case management: infection control
Standard
Apply routinely in all health-care settings for all patients.
precautions
Standard precautions include:
- hand hygiene
- and use of personal protective equipment (PPE) to avoid
direct contact with patients’ blood, body fluids, secretions
(including respiratory secretions) and non-intact skin.
When providing care in close contact with a patient with
respiratory symptoms (e.g. coughing or sneezing): use eye
protection, because sprays of secretions may occur.
Standard precautions include:
- prevention of needle-stick or sharps injury;
- safe waste management;
- cleaning and disinfection of equipment;
- and cleaning of the environment.
Source: WHO
Case management: infection control
Droplet
precautions
Use a medical mask if working within 1 meter of the
patient.
Place patients in single rooms, or group together those
with the same etiological diagnosis.
If an etiological diagnosis is not possible, group patients
with similar clinical diagnosis and based on
epidemiological risk factors, with a spatial separation of
at least 1 meter.
Limit patient movement and ensure that patients wear
medical masks when outside their rooms.
Source: WHO
Case management: infection control
Airborne
precautions
Ensure that healthcare workers performing aerosolgenerating procedures use PPE, including:
- gloves, long-sleeved gowns,
- eye protection
- and particulate respirators (N95 or equivalent).
Whenever possible, use adequately ventilated single
rooms when performing aerosol-generating
procedures.
Source: WHO