Situation at glance:
On 10 July 2023, the United Arab Emirates (UAE), notified WHO of a case of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in a 28-year-old male from Al Ain city in Abu Dhabi. The case had no history of direct or indirect contact with dromedaries, goats, or sheep. The patient was admitted to the hospital on 8 June. A nasopharyngeal swab was collected on 21 June and tested positive for MERS-CoV by polymerase chain reaction (PCR) on 23 June 2023. All 108 identified contacts were monitored for 14 days from the last date of exposure to the MERS-CoV patient. No secondary cases have been detected to date.
Since July 2013, when the UAE reported the first case of MERS-CoV, 94 confirmed cases (including this new case) and 12 deaths have been reported. Globally, the total number of confirmed MERS-CoV cases reported to WHO since 2012 is 2605, including 936 associated deaths.
WHO continues to monitor the epidemiological situation and conducts risk assessments based on the latest available information. 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.
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.
Description of the case:
On 10 July 2023, the International Health Regulations National Focal Point (IHR NFP) of the United Arab Emirates (UAE) notified WHO of a confirmed case of MERS-CoV in Abu Dhabi. The patient is a 28-year-old male, non- Emirati national living in Al Ain city, a non-healthcare worker. The case visited a private medical center multiple times between 3 and 7 June 2023, complaining of vomiting, right flank pain, and dysuria (pain when passing urine). On 8 June, the case presented to a government hospital with vomiting, and gastrointestinal symptoms including diarrhea, and was given an initial diagnosis of acute pancreatitis, acute kidney injury, and sepsis.
On 13 June, he was in critical condition and referred to an intensive care unit (ICU) at a specialized government tertiary hospital where he was put on mechanical ventilation. He deteriorated and a nasopharyngeal swab was collected on 21 June and tested positive for MERS-CoV by PCR on 23 June 2023.
The case has no known co-morbidities, no history of contact with MERS-CoV human cases, and no recent travel outside the UAE. The patient has no known history of direct contact with animals including dromedary camels, nor consumption of their raw products.
All 108 contacts that were identified have been monitored for 14 days from the last date of exposure to the MERS-CoV patient, no secondary case was identified. The case has no family members or household contacts identified in the UAE.
Prior to this notification, the last MERS-CoV infection reported from the UAE was in November 2021. The first laboratory-confirmed case of MERS-CoV in UAE was in July 2013. Since then, the UAE has reported 94 cases of MERS-CoV (including this current case) and 12 associated deaths (Case Fatality Ratio (CFR): 13%).
Epidemiology of the disease:
Middle East respiratory syndrome (MERS) is a viral respiratory infection that is caused by a coronavirus called Middle East respiratory syndrome coronavirus (MERS-CoV). Humans are infected with MERS-CoV from direct or indirect contact with dromedary camels who are the natural host and zoonotic source of the MERS-CoV infection.
MERS-CoV infections range from asymptomatic or mild respiratory symptoms to severe acute respiratory disease and death. A typical presentation of a person with MERS-CoV disease is fever, cough and shortness of breath. Pneumonia is a common finding, but not always present. Gastrointestinal symptoms, including diarrhoea, have also been reported. The virus appears to cause more severe disease in older people, persons with weakened immune systems and those with chronic diseases such as renal disease, cancer, chronic lung disease, and diabetes. Severe illness can cause respiratory failure that requires mechanical ventilation and support in an intensive care unit resulting in high mortality.
No vaccine or specific treatment is currently available, although several MERS-CoV-specific vaccines and treatments are in development. Treatment is supportive and based on the patient’s clinical condition.
Public health response
- A total of 108 contacts from health care facilities were identified and screened for MERS-CoV (56 from the first government hospital and 52 from the second government hospital) all of which were health care workers (HCWs), screening for exposed HCWs was repeated by respiratory samples, all results were negative.
- All 108 identified contacts were monitored for 14 days from the last date of exposure to the MERS-CoV patient, and no secondary cases have been detected to date.
- Abu Dhabi Public Health Centre (ADPHC) has updated the case definition for MERS-CoV, strengthened surveillance activities to identify possible cases, conducted several workshops and issued circulars for MERS-CoV.
WHO risk assessment
Middle East Respiratory Syndrome (MERS) is a viral respiratory infection of humans and dromedary camels which is caused by a coronavirus called the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Infection with MERS-CoV can cause severe disease in humans resulting in high mortality. Approximately 35% of 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. Until more is known about the disease, the case fatality rates are counted only amongst the laboratory-confirmed cases reported to WHO.
Humans are infected with MERS-CoV from direct or indirect contact with dromedaries, a host and zoonotic source of MERS-CoV infection. MERS-CoV has demonstrated the ability to be transmitted between humans. So far, the observed non-sustained human-to-human transmission has occurred among close contacts and in healthcare settings. Outside of the healthcare setting, there has been limited human-to-human transmission.
Cases of MERS-CoV infection are rare in the UAE. Since July 2013, a total of 94 MERS-CoV cases, including this current case, resulting in 12 deaths (CFR 13%) have been reported to WHO from the UAE.
Globally, the total number of laboratory-confirmed MERS-CoV cases reported to WHO since 2012 is 2605, including 936 associated deaths as of July 2023. 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 the Republic of Korea and one in China) and 38 deaths were reported. The global number reflects the total number of laboratory-confirmed cases and deaths reported to WHO under IHR (2005) to date.
The notification of this case 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.
Given that this latest case presents with severe disease but has no comorbidities and no exposure history to camels, camel raw products or MERS-CoV human case, it will be important to sequence the virus and conduct genomic analysis to screen for any unusual patterns. The process for genomic analysis has begun. This will identify any genetic evolution of the virus and support WHO’s global risk assessment efforts.
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 carefully 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. Health -care facilities should ensure environmental and engineering controls are in place including adequate ventilation, spatial separation of at least one meter between patients and others, including health and care workers and adequate environmental cleaning. Health care workers should consistently apply standard precautions to all patients at every interaction in healthcare settings. Droplet precautions, including eye protection, should be applied in addition to standard precautions when providing care to patients with symptoms of acute respiratory infection; contact precautions 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. Early identification, case management and isolation of cases, quarantine of contacts, appropriate infection prevention and control measures in health care settings, and public health awareness can prevent human-to-human transmission of MERS-CoV.
MERS-CoV appears to cause more severe disease in people with underlying chronic medical conditions such as diabetes, renal failure, chronic lung disease, and in immunocompromised persons. Therefore, people with these underlying medical conditions should avoid close contact with animals, particularly dromedaries, when visiting farms, markets, or barn areas where the virus is known to be potentially circulating.
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.
Further information
- MERS-CoV Fact sheet: https://www.who.int/en/news-room/fact-sheets/detail/middle-east-respiratory-syndrome-coronavirus-(mers-cov)
- Infection prevention and control during health care for probable or confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection Interim guidance: https://apps.who.int/iris/handle/10665/174652
- MERS-CoV global summary and assessment of risk: https://www.who.int/publications/i/item/WHO-MERS-RA-2022.1
- EPI-WIN Update 88: MERS-CoV, a circulating coronavirus with epidemic and pandemic potential – Pandemic preparedness, prevention and response with a One Health approach: https://www.who.int/publications/m/item/update-88-mers-cov-a-circulating-coronavirus-with-epidemic-and-pandemic-potential-pandemic-preparedness–prevention-and-response-with-a-one-health-approach
- Middle East Respiratory Syndrome Overview: https://www.who.int/health-topics/middle-east-respiratory-syndrome-coronavirus-mers#tab=tab_1
- WHO-EMRO MERS monthly bulletin: https://www.emro.who.int/health-topics/mers-cov/mers-outbreaks.html?format=html
- Middle East Respiratory Syndrome Outbreak Toolbox: https://www.who.int/emergencies/outbreak-toolkit/disease-outbreak-toolboxes/mers-outbreak-toolbox
- MERS outbreak in the Republic of Korea, 2015: https://www.who.int/westernpacific/emergencies/2015-mers-outbreak
- Korea Disease control and Prevention agency, Middle East Respiratory Syndrome (MERS) outbreak in 2015: https://www.kdca.go.kr/contents.es?mid=a30329000000
- United Arab Emirates (UAE) EIS November 2021: https://extranet.who.int/ihr/eventinformation/event/2021-e000387
Citable reference: World Health Organization (24 July 2023). Disease Outbreak News; Middle East Respiratory Syndrome Coronavirus in United Arab Emirates. Available at https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON478