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Although reporting has declined substantially over the past few years, on Friday the ECDC announced another MERS-CoV fatality from Saudi Arabia (see below). This makes the 12th case reported by the Saudis in 2025 (3 fatal).
Coronavirus (MERS-CoV) – Multi-country –Monthly update
Overview:
Update: Since the previous update on 1 September 2025, and as of 6 October 2025, one new MERS fatality in Saudi Arabia with date of onset in July 2025 has been reported by the World Health Organisation Eastern Mediterranean Region (WHO EMRO). The case reported no contact with camels, had comorbidities, and resided in the Riyad province. All close contacts are being followed up with no secondary cases reported so far.Summary: Since the beginning of 2025, and as of 6 October 2025, 12 MERS cases have been reported in Saudi Araba with date of onset in 2025, including three fatalities. Since April 2012, and as of 6 October 2025, a total of 2640 cases of MERS, including 958 deaths, have been reported by health authorities worldwide.
Even when countries aggressively look for cases (and many appear disinclined), detecting MERS-CoV can be difficult. Official case counts are widely 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:
EID Journal: Sensitivity and Specificity Of MERS-CoV Antibody Testing
AJIC: Intermittent Positive Testing For MERS-CoV
JIDC: Atypical Presentation Of MERS-CoV In A Lebanese Patient
Prior to SARS-CoV-2's arrival in late 2019, MERS-CoV was the top contender for sparking a coronavirus pandemic, sporting a high mortality rate, and spreading easily through hospitals in the Middle East (and South Korea) (see Ziad Memish: Two MERS-CoV Hospital Super Spreading Studies).
Last June we looked at an editorial in Journal of Epidemiology & Global Health on the importance of continued healthcare preparedness and surveillance (see Al-Tawfiq & Memish On Recurrent MERS-CoV Transmission in Saudi Arabia), with an emphasis on identifying asymptomatic carriers.
Also 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.
While MERS-CoV appears to be less of a threat today than it was a decade ago, it continues to evolve and adapt, making worth keeping our eyes on it.
To that end, we have a narrative review - published last week in Health Science Reports - on the global public heath potential of MERS-CoV. This is actually a quite lengthy (17-page PDF) report, so I've just reproduced the Abstract below.
Follow the link to read it in its entirety.
A Narrative Review on the Recent Insights Into the Pathogenicity and Potential Role of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in the Emergence of “Disease X”
Zubaier Ahmed, Kazi Milenur Rahman Prattay, Sabrina Sharmin, Fatema-Tuz-Zohora, Asef Raj, Forhad Bin Faruk … See all authors
First published: 06 October 2025
https://doi.org/10.1002/hsr2.71327
ABSTRACT
Background and Aims
Following the end of the COVID-19 global emergency, concern has shifted to “Disease X,” a hypothetical, highly transmissible, and deadly pathogen, and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a prime candidate for this. This review explores its epidemiology, mutations, transmission, and potential to become a pandemic-capable pathogen, aiming to support future research and public health preparedness against the disease.
Methods
A comprehensive search of major databases was conducted for peer-reviewed English articles (2000–2025) focusing on virology, outbreaks, treatments, and public health using relevant but definite keywords. Studies met strict inclusion criteria and standardized methods to ensure quality, reproducibility, and transparency.
Results
Since it was identified in 2012, MERS-CoV has spread across 27 countries, presenting a high case fatality rate (~34.5%) and zoonotic origin. It is primarily linked to dromedary camels, but shows limited human-to-human transmission (R₀ < 1). Unlike SARS-CoV-2, MERS-CoV's spread is confined to close contact and healthcare settings, largely in the Middle East and parts of Africa. Its pathogenesis involves severe respiratory illness, driven by immune evasion and systemic inflammation, especially in individuals with comorbidities. While MERS-CoV lacks pandemic-level transmissibility, its genetic plasticity poses a risk for future evolution. Vaccine and therapeutic development remain limited due to sporadic outbreaks and low global urgency.
Conclusion
Despite not currently fitting the Disease X archetype, MERS-CoV's high mortality, zoonotic spillover potential, and possibility for increased transmissibility warrant continued surveillance, targeted research, and strengthened public health infrastructure to prevent localized outbreaks from escalating into broader crises
For decades influenza A was considered the primary viral pandemic threat to humanity. But after SARS in 2002-2003 followed by COVID in 2019, we've learned there are plenty of other legitimate contenders in the wild (see OFID: Viral Families with Pandemic Potential).
While MERS and SARS get the bulk of our attention, over the years we've looked at a number of non-MERS/SARS coronaviruses - often carried by bats, swine and even cattle - with zoonotic potential.
- In 2014, in SECD: Another Emerging Coronavirus Threat - in the wake of several newly discovered coronaviruses detected in North American swine - we looked at growing concerns that some porcine-adapted coronaviruses might have zoonotic potential, given the similar physiology between our two species.
- In the summer of 2017 we looked at paper published in the EID Journal: A New Bat-HKU2–like Coronavirus in Swine, China, 2017, on the recent discovery of a new HKU2-like coronavirus in Chinese pigs showing symptoms of PED (Porcine Epidemic Diarrhea), which they tentatively named porcine enteric alphacoronavirus (PEAV).
- Also that summer, in a letter published in the Journal of Medical Virology, Chinese scientists made a case for the Potential Cross-Species Transmission Risks of Emerging Swine Enteric Coronavirus to Human Beings.
- Last year we looked at the concerns over the Circulation of Non-(MERS) Coronaviruses in Imported Camels in Saudi Arabia and a preprint on Human Cell adaptation of the Swine Acute Diarrhea Syndrome Coronavirus Spike Protein
- And just five months ago, in J. of Infection: Novel Coronaviruses Identified in Livestock we looked at a warning from Chinese researchers on risks of livestock-borne coronaviruses.
