Middle East respiratory syndrome coronavirus (MERS-CoV) - Qatar
12 May 2022
Outbreak at a glance
From 22 March to 3 April 2022, two laboratory-confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV), including one death, were reported to the WHO by the National IHR Focal Point of Qatar. Both cases had frequent close contact with dromedary camels and consumption of their raw milk in the 14 days prior to the onset of symptoms. The Qatar Ministry of Public Health immediately initiated case investigation and contact tracing. These are the first cases of MERS-CoV infection reported from Qatar since February 2020. The notification of these cases reiterates the need for global awareness of MERS-CoV but does not change the overall risk assessment. WHO expects that additional cases of MERS-CoV infection will be reported from the Middle East and/or other countries where MERS-CoV is circulating in dromedaries.
Outbreak overview
Between 22 March and 3 April 2022, the National IHR Focal Point of Qatar reported two laboratory-confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection to the WHO.
The first case was a 50-year-old male, working and living in a camel farm in Al Shaniya Doha. On 16 March, the case presented to the emergency department at Hamad Medical Corporations in Doha with a history of productive cough for one-week, high grade fever and shortness of breath. The patient was admitted to the medical ward on 17 March, and on 18 March due to a deterioration of the health status was transferred to the Intensive Care Unit (ICU). A nasopharyngeal swab was collected and tested positive for MERS-CoV by reverse transcription polymecercarase chain reaction (RT-PCR) (upE and Orf1a genes) at the virology laboratory, Hamad Medical Corporation on 19 March. The patient has no comorbidities, and reported frequent close contact with dromedary camels and consumption of their raw milk in the 14 days prior to the onset of symptoms. No recent travel history was reported for the case or any of the case’s contacts. None of the identified four contacts reported symptoms of the disease and all tested MERS-CoV negative. No further information on the health status of the case is available at the time of writing.
The second case was an 85-year-old male, dromedary camel owner living in Doha. On 18 March, the patient presented to the emergency department at Hamad Medical Corporations with a history of productive cough for one-week, high grade fever and shortness of breath, and was admitted to the medical ward on the same day, during which the clinical status of the patient deteriorated. A nasopharyngeal swab was collected and tested positive for MERS-CoV by RT-PCR (upE and ORF1a genes) at the Hamad Medical Corporation virology laboratory on 19 March. On 22 March, the patient was intubated and transferred to the ICU where he died on 14 April. The patient had comorbidities including diabetes mellitus, hypertension, and hypercholesterolemia. The epidemiological investigation revealed that 14 days prior to admission to the hospital the case had travelled with his camel to Saudi Arabia, where he visited other dromedary camel owners. The case also reported frequent contact with dromedary camels, as well as consuming raw milk from dromedary camels in Saudi Arabia.
The case initially presented to a health centre while he was in Saudi Arabia, with symptoms including vomiting, loss of appetite, fever, and chills. He was subsequently diagnosed with an acute urinary tract infection. The medical staff at the health center in Saudi Arabia referred him to a hospital, but he decided to return to Qatar immediately. Investigation of 12 household contacts and health care workers has been completed and all have tested negative for MERS-CoV . The IHR-NFP of Saudi Arabia has also been notified.
Before these notifications, the last MERS-CoV infection reported from Qatar was in February 2020. Since 2012, Qatar has reported a total of 28 human cases of MERS-CoV, and 7 deaths, including the two new reported cases. There have been no hospital outbreaks or reported infections among healthcare workers.
Public health response
According to the national protocol for management of MERS-CoV cases, both patients were isolated, and the infection prevention and control protocol was activated. The Ministry of Public Health immediately initiated case investigation and contact tracing. Respiratory swabs were collected from 12 household contacts, 4 co-workers and 15 health care workers and all tested negative for MERS-CoV. None of the above contacts reported any symptoms of MERS-CoV. All contacts have been monitored until the end of their monitoring period (14 days from the last exposure to the patients) and no secondary cases were identified. Infection prevention and control measures in all health facilities have been reinforced by the Ministry of Public Health. Health education messages about appropriate preventive measures will be shared with all contacts and they will be advised to comply with the recommended public health measures for MERS-CoV and to report to the health authorities if they develop any respiratory symptoms. The Animal Health Resources Department has been notified and investigation of dromedary camels is ongoing.
WHO risk assessment
MERS-CoV is a viral respiratory infection of humans and dromedary camels which is caused by a coronavirus called Middle East Respiratory Syndrome Coronavirus. Infection with MERS-CoV can cause severe disease resulting in high mortality. Approximately 35% of reported patients with MERS-CoV have died, but this may be an overestimate of the true mortality rate, as mild cases of MERS-CoV may be missed by existing surveillance systems and the case fatality rates are counted only amongst the laboratory-confirmed cases.
Humans are infected with MERS-CoV from direct or indirect contact with dromedaries who are the natural host and zoonotic source of MERS-CoV infection. MERS-CoV has demonstrated the ability to transmit between humans but it has, so far, mainly occurred in health care settings and to a limited extent among close contacts.
One of the new reported cases had travel history outside of Qatar and it is likely that the infection was acquired as a result of zoonotic infection from direct or indirect contact with infected dromedary camels. WHO expects that additional cases of MERS-CoV infection will be exported from countries where MERS-CoV is circulating in dromedaries by travelers who may acquire infection after exposure to: 1) infected dromedaries or dromedary products (for example, following contact with camels); or 2) to infected humans (for example, in a health care setting).
As of 12 May 2022, the total number of laboratory-confirmed MERS-CoV infection cases reported globally to WHO is 2591 including 894 associated deaths and reflects the total number of laboratory-confirmed cases and deaths reported to WHO under IHR (2005) to date. The majority of the reported cases have occurred in countries in the Arabian Peninsula. Outside of this region, there has been one large outbreak in the Republic of Korea, in May 2015, during which 186 laboratory-confirmed cases (185 in Republic of Korea and 1 in China) and 38 deaths were reported.
The notification of these cases does not change the overall risk assessment. WHO expects that additional cases of MERS-CoV infection will be reported from the Middle East and/or other countries where MERS-CoV is circulating in dromedaries, and that cases will continue to be exported to other countries by individuals who were exposed to the virus through contact with dromedaries or their products (for example, consumption of camel’s raw milk), or in a healthcare setting. WHO continues to monitor the epidemiological situation and conducts risk assessments based on the latest available information.
WHO advice
Based on the current situation and available information, WHO re-emphasizes the importance of strong surveillance by all Member States for acute respiratory infections, including MERS-CoV, and to carefully review any unusual patterns.
As a general precaution, anyone visiting farms, markets, barns or other places where dromedaries are present, should practice general hygiene measures, including regular hand washing after touching animals, avoiding touching eyes, nose or mouth with hands, and avoiding contact with sick animals. People may also consider wearing protective gowns and gloves while professionally handling animals.
The consumption of raw or undercooked animal products, including milk, meat, blood and urine, carries a high risk of infection from a variety of organisms that might cause disease in humans. Animal products processed appropriately through proper cooking or pasteurization are safe for consumption but should also be handled with care, to avoid cross-contamination with uncooked foods.
Human-to-human transmission of MERS-CoV in healthcare settings has been associated with delays in recognizing the early symptoms of MERS-CoV infection, slow triage of suspected cases and delays in implementing infection, prevention and control (IPC) measures. IPC measures are therefore critical to prevent the possible spread of MERS-CoV between people in health care facilities.
Early identification, case management and isolation of cases, quarantine of contacts, together with appropriate infection prevention and control measures in health care setting and public health awareness can prevent human-to-human transmission of MERS-CoV.
Healthcare workers should always apply standard precautions consistently with all patients, at every interaction in healthcare settings.
- Droplet precautions should be added to the standard precautions when providing care to patients with symptoms of acute respiratory infection;
- Contact precautions and eye protection should be added when caring for probable or confirmed cases of MERS-CoV infection;
- Airborne precautions should be applied when performing aerosol generating procedures or in settings where aerosol generating procedures are conducted.
WHO does not advise special screening at points of entry with regard to this event nor does it currently recommend the application of any travel or trade restrictions.