From September 13, 2022, to August 12, 2023, the Kingdom of Saudi Arabia (KSA) reported three laboratory-confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV) to the World Health Organization (WHO). Among these cases, two individuals tragically succumbed to the virus. The Ministry of Health of KSA undertook comprehensive follow-ups on close contacts related to the three cases, and reassuringly, no secondary cases were identified. These occurrences underscore the ongoing global need for vigilance and awareness of MERS-CoV, particularly in regions where the virus is prevalent among dromedary camels, including the Middle East.
Between September 13, 2022, and August 12, 2023, KSA’s Ministry of Health reported three additional cases of MERS-CoV, accompanied by two fatalities. These cases were recorded in various regions: Riyadh, Asser, and Makkah Al Mukarramah (Figure 1). Rigorous laboratory confirmation was conducted using real-time polymerase chain reaction (RT-PCR) testing.
All three cases involved non-healthcare workers, who presented symptoms such as fever, cough, and shortness of breath, and had existing medical conditions. Notably, two of the cases had direct contact with dromedary camels, while all three cases consumed raw camel milk within two weeks preceding symptom onset. The age range of the affected individuals was 42, 83, and 85 years (Table 1).
Since the initial MERS-CoV report in KSA in 2012, human infections have been documented across 27 countries and all six World Health Organization (WHO) regions. KSA remains at the forefront with the highest number of reported cases, accounting for 2,196 out of 2,605 globally. Furthermore, out of 937 reported deaths worldwide, 856 occurred in KSA, including the recent cases.
Epidemiology of MERS-CoV:
MERS, caused by the Middle East respiratory syndrome coronavirus (MERS-CoV), results in a viral respiratory infection. The mortality rate among MERS patients is approximately 36%. The virus is primarily transmitted to humans through direct or indirect contact with dromedary camels, the natural host and zoonotic source of the virus. While human-to-human transmission has been observed, it remains limited.
Symptoms of MERS-CoV infection can range from mild respiratory symptoms to severe acute respiratory disease, with potential fatalities. Gastrointestinal symptoms have also been reported. Severe cases can lead to respiratory failure, necessitating intensive care. Those at higher risk of severe illness include older individuals, those with weakened immune systems, and those with underlying medical conditions.
At present, there is no specific treatment or vaccine for MERS-CoV. Supportive care is administered based on clinical conditions.
Public Health Response:
All close contacts of the three cases were closely monitored, and no secondary cases were identified.
For cases involving contact with camels, the Ministry of Agriculture was notified, leading to an investigation of the camels involved. Isolation was implemented for positive camels until negative RT-PCR test results were obtained.
WHO Risk Assessment:
From September 13, 2012, to August 12, 2023, a total of 2,605 laboratory-confirmed MERS-CoV infections have been reported globally, with 937 associated deaths (case fatality ratio of 36%). The majority of cases (2,196 cases with 856 deaths) were reported in KSA. The risk of further cases and exportation remains, especially in regions with dromedaries carrying the virus. WHO continues to monitor the situation and conduct risk assessments.
The number of reported MERS cases has decreased due to the prioritization of COVID-19 surveillance. The ongoing pandemic has also led to decreased testing for MERS-CoV, in addition to similar clinical presentations of both diseases.
WHO emphasizes strong surveillance for respiratory infections, including MERS-CoV, and urges vigilance in identifying unusual patterns.
Effective infection prevention and control measures are essential, especially in healthcare settings. Early identification, case management, and isolation, along with hygiene practices, can help prevent human-to-human transmission. Those with underlying medical conditions should avoid close contact with dromedaries.
At present, WHO does not recommend travel or trade restrictions related to MERS-CoV.