Wednesday, August 20, 2025

IJID Editorial: Al-Tawfiq on Global Epidemiology and Public Health Challenges of Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

 
Credit WHO 

#18,844

Until the SARS-CoV virus began its limited world tour in 2002-2003, (see SARS and Remembrance), only four coronaviruses (Alpha coronaviruses 229E and NL63, and Beta coronaviruses OC43 & HKU1) were known to infect humans.
These 4 human coronaviruses were thought unlikely to produce severe disease, but were believed responsible for 15%-30% of the `common colds’ around the world.  Only rarely did they migrate to the lower respiratory tract (cite).
The SARS-CoV epidemic was followed a decade later (2012) by the emergence of MERS-CoV on the Arabian Peninsula - carried silently by camels - where it has sparked numerous large and deadly nosocomial outbreaks, and has spread (via infected travelers) to other countries.
The ECDC currently lists (as of Aug 5th, 2025) a total of 2639 cases and 957 deaths worldwide since 2012, although there are reasons to believe the actual numbers are far higher.
Even when countries aggressively look for cases, detecting MERS-CoV can be difficult, and official case counts are assumed to be undercounts (see EID Journal: Estimation of Severe MERS Cases in the Middle East, 2012–2016. Some past blogs on these challenges include: 

Today Jaffar A. Al-Tawfiq is back again (solo this time) with another editorial in the ISID (International Society of Infectious Diseases) journal - which once again stresses the importance of detecting asymptomatic cases of the disease, particularly in hospital settings. 

While it's a relatively short article, I've only posted some excerpts. Follow the link to read it in its entirety.   

Global Epidemiology and Public Health Challenges of Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Jaffar A. Al-Tawfiq1,2,3,4

Middle East Respiratory Syndrome (MERS) is a viral respiratory disease caused by the MERS coronavirus (MERS-CoV), first identified in 2012 [1,2]. The MERS-CoV Dashboard, managed by the World Health Organization (WHO), provides a centralized visualization of confirmed human cases reported through the International Health Regulations (IHR) and WHO Disease Outbreak News (DON) [3]. By providing concise summary statistics and epidemiological trends, this tool improves situational awareness, aids in risk assessment, and guides public health responses.

Since 2012, globally there have been 2,626 laboratory-confirmed cases of MERS-CoV . The vast majority—over 90%—originated from the Arabian Peninsula, with Saudi Arabia alone accounting for approximately 2,200 cases. Other countries with reported case counts include the Republic of Korea (186 cases) and the United Arab Emirates (94 cases). Sporadic cases were also reported from Jordan (28), Qatar (28), Oman (26), Iran (6), the United Kingdom (5), and several other countries[3] (Figure 1).

(SNIP)

Among all reported MERS-CoV cases, healthcare workers (HCWs) represent a substantial portion, accounting for 15% of total cases according to WHO data [3]. This reported proportion underscores the hallmark role healthcare settings play in MERS transmission. HCWs often experience greater exposure due to close contact with infected patients, and outbreaks in healthcare facilities can amplify spread [13].

Compared to non-HCW cases, infected healthcare workers tend to be younger, more often female, and have fewer comorbidities, which corresponds with a generally higher survival rate and a higher frequency of asymptomatic infections among HCWs. The case fatality rate among HCWs is substantially lower than among non-HCWs, attributable to factors like earlier detection and better baseline health [14].

Evidence indicates that asymptomatic or mildly symptomatic HCWs can carry and shed virus, posing challenges for infection prevention and control (IPC), as their unnoticed infections may silently contribute to transmission chains in clinical settings. Hospital outbreaks have often been linked to delayed diagnosis, insufficient PPE use, and lapses in IPC protocols, emphasizing the need for rigorous protective measures to safeguard healthcare workers and prevent further nosocomial spread [6,7].

Given these findings, protecting HCWs is critical both for their safety and for maintaining continuity of care. Improved awareness, strict adherence to infection control recommendations, and early identification of cases among HCWs are vital to reducing healthcare-associated outbreaks [7,14,15]. The significant burden brought by healthcare workers, including psychological and workforce impacts, makes investment in their protection a public health priority in regions where MERS-CoV is endemic

(SNIP)

In conclusion, MERS-CoV continues to pose a substantial threat, particularly in regions with close human-animal interface and in healthcare settings where infection control measures may be insufficient. The demographic skew toward older adults with comorbidities, the high case fatality rate, and the absence of targeted therapeutics or vaccines highlight the urgent need for sustained surveillance, research, and investment in preventive strategies.

Lessons learned from MERS are also directly applicable to preparedness for other emerging zoonotic diseases, reinforcing the importance of a One Health approach to global health security. 

        (Continue . . . )

Prior to the emergence of COVID in 2019, MERS-CoV was viewed as being the top coronavirus pandemic threat (see 2017's A Pandemic Risk Assessment Of MERS-CoV In Saudi Arabia), with its R0 (basic reproduction number) briefly flirting with 1.0.

While case reports have dwindled in recent years, the virus still circulates in camels, and the zoonotic risk has not gone away.

Last June, in JEGH: Epidemiological Characteristics of MERS-CoV Human Cases, 2012- 2025, we looked at the changing epidemiology of MERS-CoV cases since 2012, as well as substantial gaps in our current understanding of the disease.

A reminder that just because MERS-CoV activity is often out of sight, it shouldn't be out of mind. 

Posted by at