Public health priority: Urgent. MERS coronavirus is a scheduled disease under NSW Public Health Act 2010 with notification required by doctors, hospitals and laboratories.
Case management: Isolate suspected cases in a single room with negative pressure air-handling (if available) and use standard and transmission-based precautions (contact and airborne).
Contact management: Close contacts are monitored for development of fever and respiratory symptoms in the 14 days following the last contact.
Urgent.
MERS coronavirus is a scheduled disease under NSW Public Health Act 2010 with notification required by doctors, hospitals and laboratories.
In other jurisdictions, advice should be sought, where applicable, from the relevant State or Territory central Communicable Diseases agency on the process for reporting of suspected, probable and confirmed MERS-CoV cases. MERS-CoV infection was not a nationally notifiable disease.
Isolate suspected cases in a single room with negative pressure air-handling and an en-suite bathroom (if available) and use standard and transmission-based precautions (contact and airborne).
Close contacts of probable and confirmed cases are subject to some work and travel restrictions and should be actively monitored for development of fever and respiratory symptoms in the 14 days following the last contact, while casual contacts are subject to self-monitoring only.
The Middle East respiratory syndrome coronavirus (MERS-CoV).
Coronaviruses are a large and diverse family of viruses that include viruses that are known to cause illness in humans (including the common cold) and animals.
It is likely that the virus has come from an animal source. MERS-CoV has been detected in camels in several Middle East countries with human cases of MERS-CoV infection. Additionally, serological evidence of camel exposure to MERS-CoV or a closely related virus has been found in camels over a wide area of northern Africa and the Middle East. It is suspected, but not confirmed, that infected camels may be the source of the virus for some human cases. There are also limited reports of MERS-CoV being detected in bats.
More information is needed to identify the possible role that camels, bats, and other animals may play in the transmission of MERS-CoV. MERS-CoV is genetically distinct from SARS-CoV, and appears to behave differently, being less transmissible but with a higher mortality rate. However, the full spectrum of illness remains unclear.
The mode or modes of transmission of MERS-CoV are not fully known.
There have been some cases with a strong history of exposure to camels or camel products (e.g. milk), including at least one cluster where the camels also tested positive. However, there have been many sporadic cases with no history of prior exposure to camels or other animals.
There have been multiple clusters of cases in which human-to-human transmission has occurred. These clusters have been observed in health-care facilities, among family members and between co-workers. However, the mechanism by which transmission occurred in these cases, whether respiratory (e.g. coughing, sneezing) or direct physical contact with the patient or via fomites after contamination of the environment by the patient, is unknown.
Infection control recommendations for managing suspected, probable and confirmed cases are consistent with those recommended for SARS-CoV and pandemic influenza. As further information becomes available, these recommendations will be re-evaluated and updated as needed.
From 2 to 14 days; most commonly 5 days.
The duration of infectivity for MERS-CoV infection is unknown. Standard Precautions should be applied throughout any admission; additional isolation precautions should be continued until 24 hours after the resolution of symptoms.
Given that little information is currently available on viral shedding and the potential for transmission of MERS-CoV, testing to detect the virus may be necessary to inform decision-making on infectiousness. Patient information (e.g. age, immune status and medication) should also be considered.
Clinical presentation ranges from asymptomatic to severe pneumonia with acute respiratory distress syndrome and multi-organ failure. Nearly all symptomatic patients have presented with fever. Respiratory symptoms are common and gastrointestinal symptoms are less commonly reported.
Typically, the disease starts with fever and cough. Other common symptoms are myalgia and chills. Sore throat, arthralgia, dyspnoea, nausea, vomiting and diarrhoea are less commonly present. In the 2015 South Korean outbreak, pneumonia was present in a minority of patients at initial presentation but it is unclear whether early testing of contacts with, at the time, milder clinical manifestations of MERS-CoV infection may have influenced the reported spectrum of illness.
Patients who develop pneumonia or pneumonitis often require mechanical ventilation and other organ support. The case fatality rate for confirmed cases is estimated at 30-40 per cent, but this may decrease when the spectrum of disease is better understood, as suggested by lower case fatality observed in the South Korean outbreak.
The age distribution of reported cases is skewed heavily to the middle-aged and elderly. Cases who are elderly, immunocompromised or with co-morbidities have an increased case fatality rate [1].
As of June 2015 there have been no confirmed MERS-CoV cases reported in Australia.
Countries that have reported cases in the Middle East include Iran, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia (KSA), United Arab Emirates (UAE) and Yemen, with Saudi Arabia and UAE being most affected.
Persons who acquired MERS-CoV in Middle Eastern countries have exported the infection to many other countries, which has resulted in health facility outbreaks in France, the United Kingdom, and most notably South Korea. For a full list of countries where MERS-CoV cases have been detected see the World Health Organization (WHO) coronavirus infection website [1].
WHO expects that additional cases of MERS-CoV infection will be reported from the Middle East, and that it is likely that cases will continue to be exported to other countries by tourists, travellers, guest workers or pilgrims who might acquire infection following exposure to human cases (possibly in a health care setting), or possibly from camels or other unknown animal sources (for example, while visiting farms or markets).
Until more is understood about the mode of transmission and risk factors for infection, it is expected that sporadic cases will continue to occur, with potential for limited transmission within households and healthcare settings.
It is recommended that people with significant medical conditions such as diabetes, renal disease and chronic lung disease who are intending to travel to the Middle East – including those undertaking the Hajj or Umrah - should consult a doctor prior to travel.
People travelling in countries affected by MERS-CoV should maintain good hygiene practices, avoid contact with animals, especially camels, and refrain from consuming unpasteurised milk or undercooked meat.
Travellers to the Middle East and travel organisations should be advised of general travel health precautions which will lower the risk of infection in general, including respiratory viruses and traveller’s diarrhoea. Specific emphasis should be placed on:
Travel advice for Australians is available at the Australian Department of Health MERS-CoV web page [2]. Travellers should check if there are any travel restrictions in place prior to travel.
Confirmed, probable and suspected cases of MERS-CoV infection should be entered onto the NCIMS database within one working day of notification/report.
Where applicable, public health units should immediately notify the central state/territory communicable diseases agency of suspected, probable and confirmed cases once notifications/reports are received. Provide the case’s age, sex, place of residence, indigenous status, date of onset, travel history, laboratory results, clinical status, likely place of acquisition, and follow-up action taken.
State/territory communicable diseases agency should immediately notify probable and confirmed MERS-CoV cases to the National Incident Room.
Knowledge and understanding of MERS-CoV infection continues to expand. The following criteria are based on case series reported from recent outbreaks and represent combinations of symptoms and epidemiological criteria in which MERS-CoV testing is strongly recommended.
Atypical presentations occur, and clinical and public health judgement should also be used to determine the need for testing in patients who do not meet the criteria below.
Testing and initial infection control and public health actions for MERS-CoV should be undertaken for persons with:
Confirmed and probable cases should be nationallly notified.
A confirmed case requires laboratory definitive evidence only.
Detection of MERS coronavirus by polymerase chain reaction (PCR) in a public health reference laboratory using the testing algorithm described in Appendix 3 and summarised below. [6]
A probable case requires clinical evidence and epidemiological evidence.
Close contact with a laboratory-confirmed case.
See Section 8. Laboratory testing and Appendix 3 for additional MERS-CoV laboratory testing information.
Patients to be considered for MERS-CoV testing are described under the suspected case definition (see above). Consult with the Communicable Diseases Branch, Health Protection NSW to seek advice on which NSW laboratories can provide MERS-CoV testing, the appropriate specimen types, collection and transport advice, and also to facilitate contact management if indicated.
Transmission-based contact and airborne precautions must be used when collecting respiratory specimens [3]. These include:
Routine tests for acute pneumonia/pneumonitis should be performed where indicated, including bacterial cultures, acute and convalescent serology, urinary antigen testing and tests for respiratory viruses, according to local protocols.
Serology, if available, may be useful in cases where MERS-CoV is strongly suspected but non-confirmed with nucleic acid testing (NAT), but requires paired acute and convalescent sera – seek expert clinical microbiology advice. Serology is also useful to estimate secondary infection rates in asymptomatic cases following exposure to MERS-CoV.
Refer to Appendix 3 for additional MERS-CoV laboratory testing information.
On the same day as notification of a suspected, probable or confirmed case, begin follow up investigation and notify the Communicable Diseases Branch, Health Protection NSW.
The response to a notification will normally be carried out in collaboration with the clinicians managing the case, and be guided by the MERS-CoV public health unit checklist (Appendix 2) and the MERS-CoV Investigation Form (Appendix 4).
Regardless of who does the follow-up, PHU staff should ensure that action has been taken to:
Note: If interviews with suspected cases are conducted face-to-face, the person conducting the interview must have a thorough understanding of infection control practices and be competent in using appropriate PPE.
Wherever possible, cases should be managed in hospital. If clinically indicated, cases may be managed at home only if it can be ensured that the case and household contacts are counselled about risk and that appropriate infection control measures are in place.
In the absence of pathogen-specific interventions, patient management largely depends on supportive treatment, and vigilance for and prevention of complications.
Further advice on clinical management is available from WHO [4].
Provide MERS-CoV fact sheets (Appendix 1) to cases and their close contacts. Ensure that they are aware of the signs and symptoms of MERS-CoV, the requirements of isolation, contact details of the PHU and the infection control practices that can prevent the transmission of MERS-CoV.
Cases must be isolated in an appropriate health facility, unless alternative arrangements are recommended on expert advice. Healthcare workers and others who come into contact with suspected, probable and confirmed cases must be protected according to recommended infection control guidelines. Visitors should be restricted to close family members.
A risk assessment should be undertaken for suspected cases who initially test negative for MERS-CoV. If there is no alternative diagnosis and a high index of suspicion remains that such cases may have MERS-CoV infection, consideration should be given to continued isolation and use of the recommended infection control precautions, pending further testing (see Section 8. Laboratory testing and Appendix 3) and re-assessment.
Given the severity of reported infections, the evidence of limited person-to-person transmission, and gaps in knowledge of transmission pathways, the recommendations on isolation and PPE for management of suspected, probable and confirmed cases take a deliberately cautious approach.
Infection control measures should be those applicable to control the transmission of pathogens that can be spread by the airborne route. These measures are detailed in the Interim infection prevention and control advice for acute care hospitals relating to suspected Middle Eastern respiratory syndrome coronavirus (MERS-CoV) infections [3].
In summary, transmission-based precautions for suspected, probable and confirmed cases should include:
Contacts (see Section 11. Contact management) should be identified and advised to immediately seek medical advice should they develop symptoms. Contacts or caregivers should be asked to also inform the public health agency if they develop symptoms.
Where local transmission of MERS-CoV is thought possible, a thorough review of contributing environmental factors should be done. This should include a review of infection control procedures, and opportunities for exposure to respiratory or faecal contamination.
If a case has had occupational exposure to animals it may be appropriate to consult with animal health authorities.
As there remain gaps in the understanding of infectivity of MERS-CoV cases and transmission modes the definition of contacts is based on observations of people infected in large outbreaks, particularly the outbreak in South Korea. The definition of contacts and recommended control measures are subject to review as more information on MERS-CoV becomes available.
All persons categorised as a contact (see definitions of "close contacts" and "casual contacts" following) of probable and confirmed cases should be followed-up and monitored for the development of symptoms for 14 days after the last exposure to the case (i.e. the maximum incubation period).
Close contacts of suspected cases should also be considered for contact management if there is likely to be a delay in confirming or excluding the suspected case, such as delayed testing.
A close contact is defined as requiring greater than 15 minutes face-to-face contact with a symptomatic probable or confirmed case in any setting, or the sharing of a closed space with a symptomatic probable or confirmed case for a prolonged period (e.g. more than 2 hours).
Hence, close contacts may include:
Contact tracing by public health units should prioritise identifying close contacts particularly healthcare workers, and other close contacts who may be at higher risk of severe disease, including the elderly and those with significant co-morbidities.
Casual contact is defined as any person having less than 15 minutes face-to-face contact with a symptomatic probable or confirmed case in any setting, or sharing a closed space with a symptomatic probable or confirmed case for less than 2 hours. This will include healthcare workers, other patients, or visitors who were in the same closed healthcare space as a case, but for shorter periods than those required for a close contact. Other closed settings might include schools or offices.
Note that healthcare workers and other contacts who have taken recommended infection control precautions, including the use of full PPE, while caring for a symptomatic probable or confirmed MERS-CoV case are not considered to be close contacts. However, these people should be advised to self-monitor and if they develop symptoms consistent with MERS-CoV infection they should isolate themselves and notify their public health unit or staff health unit so they can be tested and managed as a suspected MERS-CoV case (see recommendations below under Management of symptomatic contacts).
Other casual contacts may include:
Where resources permit, more active contact tracing may be extended to other persons who have had casual contact (as defined above), particularly in school, office, or other closed settings. In these circumstances, the size of the room/space and degree of separation of the case from others should be considered in identifying contacts.
All persons identified as having had contact with a symptomatic probable or confirmed case should be assessed to see if they should be classified as a close contact and have demographic and epidemiological data collected. Information on close contacts should be managed according to jurisdictional requirements.
Identification and assessment of the contacts of suspected cases may be deferred pending the results of initial laboratory testing. However, contact tracing should be considered if MERS-CoV infection remains high on the list of differential diagnoses, even if initial laboratory results are negative or are pending.
Routine laboratory screening for MERS-CoV infection is not recommended for asymptomatic contacts. One exception is in the setting of a hospital outbreak, where WHO recommends RT-PCR testing of nose/throat swabs of asymptomatic close contacts be considered, if feasible. RT-PCR-positive asymptomatic close contacts in this setting should be isolated, monitored closely for symptoms and only released from isolation following two negative RT-PCR tests separated by 24 hours [5]
Serological testing of close contacts may be useful, if available, in order to help determine the secondary infection-attack rate and the proportion of infections that are asymptomatic. Contacts who agree to be tested should be advised that serological testing will not be done immediately and is not being conducted for contact management purposes.
Consent should be sought from household and healthcare worker close contacts for the collection of the following samples:
The collection of nasopharyngeal (NP) swabs from asymptomatic close contacts for MERS-CoV nucleic acid testing (NAT) is not recommended. There is little information available currently to reliably inform the timing of testing or the interpretation of negative test results in this setting.
Serial PCR testing of NP swabs from asymptomatic close contacts to detect MERS-CoV viral shedding may be conducted as part of ethics-approved research studies.
No specific chemoprophylaxis is available for contacts.
Close contacts should be counselled about their risk and the symptoms of MERS-CoV and provided with a MERS-CoV fact sheet (Appendix 1). They should be advised to self-isolate if they develop symptoms, and to immediately notify their public health unit and, if appropriate, their facility infection control unit (i.e. for healthcare workers).
Home quarantine of asymptomatic contacts is not routinely recommended, but people identified as close contacts are advised to monitor their health for 14 days after the last possible contact with a symptomatic probable or confirmed MERS-CoV case.
Public health units should conduct active daily monitoring of close contacts for symptoms for 14 days after the last possible contact with a symptomatic probable or confirmed MERS-CoV case.
Close contacts should be advised to immediately telephone the public health unit to arrange medical attention if they develop symptoms such as fever, respiratory symptoms (including coughing and shortness of breath), headache, muscle pain or diarrhoea.
Less frequent active follow-up together with passive surveillance may be necessary if there are large numbers of close contacts to monitor.
Close contacts should also be advised to not travel internationally for 14 days after the last close contact with a probable or confirmed case of MERS-CoV, and any travel within Australia during this period should be subject to discussion with the public health unit.
Close contacts should be excluded from schools and sensitive occupations or settings such as health care, aged care, or child care during the 14 days after last unprotected contact with a case.
Casual contacts should monitor their health for 14 days and report any symptoms immediately to the local public health unit. There are no restrictions on movements; however casual contacts should be advised to contact the public health unit if they develop symptoms.
Healthcare worker close contacts (i.e. persons exposed while unprotected, as described in the Contact definition section) should not undertake work in a healthcare setting for 14 days following the last possible contact with the case. Home quarantine is not routinely recommended during this period if these individuals remain asymptomatic, but some restrictions may be recommended based on a risk assessment of the particular circumstances.
Public health units may assist infection control units of health facilities to identify and monitor healthcare worker close contacts.
It is recognised that clinical work restrictions on healthcare worker close contacts may place strain on individuals and on health services. This underlines the importance of ensuring healthcare workers implement appropriate infection control precautions when assessing and managing suspected, probable and confirmed MERS-CoV cases.
These recommendations are based on reports from large health facility-based MERS-CoV outbreaks in the Middle East and South Korea which have involved nosocomial transmission of MERS-CoV to both patients and healthcare workers. CDNA will continue to monitor the emerging evidence around MERS-CoV transmission risks in healthcare settings and revise these recommendations as needed.
If fever, respiratory symptoms or other symptoms consistent with MERS-CoV infection develop within the first 14 days following the last contact, the individual should be immediately isolated and managed as per the current recommendations for suspected MERS-CoV cases, with urgent testing for MERS-CoV infection undertaken in an environment which minimises the exposure of others.
Ill contacts who are being evaluated for MERS-CoV infection can be appropriately isolated and managed at home, unless their condition is severe enough to require hospitalisation.
Symptomatic contacts who test negative for MERS-CoV by PCR will still need to be monitored for 14 days after their last contact with a probable or confirmed MERS-CoV case and may require re-testing. There have been a number of reports of MERS-CoV cases who initially tested negative for MERS-CoV by PCR.
If one or more probable or confirmed MERS-CoV cases are identified in a healthcare facility, an outbreak management team should be convened, including a senior facility manager, an infection control practitioner and appropriate clinical staff, in consultation with PHU staff. Control measures may include:
There have been few if any reports of MERS-CoV outbreaks in institutions other than in healthcare facilities, and transmission within households appears to be uncommon. Nevertheless, it is assumed that fellow residents in an institution will be at greater risk of infection if there has been a confirmed case living at the institution while infectious.
If one or more probable or confirmed MERS-CoV cases are identified in a residential care facility or institution, an outbreak management team should be convened, in consultation with PHU staff.
MERS coronavirus is a scheduled disease under the NSW Public Health Act 2010, with notification required by doctors, hospitals and laboratories.
Appendix 1 - MERS-CoV fact sheetAppendix 2 - MERS-CoV PHU checklist [PDF]Appendix 3 - MERS-CoV laboratory testing information [PDF]Appendix 4 - MERS-CoV case investigation form [PDF]