JEGH: Al-Tawfiq & Memish On Recurrent MERS-CoV Transmission in Saudi Arabia

 

Credit Wikipedia

#18,748

Jaffar A. Al-Tawfiq and Ziad A. Memish - either writing together or separately - are probably the two best known and most prolific authors on the public health aspects of the Hajj - and since its emergence in  2012 - on the novel MERS coronavirus.

A partial list of my past blogs highlighting their work include:

AJIC: Intermittent Positive Testing For MERS-CoV

Evaluation of a Visual Triage for the Screening of MERS-CoV Patients

Frontiers Med.: MERS-CoV In 7 Pediatric Patients

ATS: Mass Gatherings And Lessons From The Hajj

 

This year's Hajj (June 4th - 9th) will see over 1.6 million religious pilgrims from > 180 countries attend, and then return to their respective countries.  As with all mass gathering events, the Hajj has the potential to amplify and disperse emerging and existing infectious diseases - sometimes on a global scale (see J, Epi & Global Health: Al-Tawfiq & Memish On Hajj Health Concerns).

Most infectious illnesses acquired during these mass gathering/migration events are fairly common; seasonal flu, pneumonia, measles, meningococcal disease, norovirus, and vector borne infections (Zika, CHKV, Dengue, Malaria, Yellow Fever, etc.) (see CDC's Traveler's Health Saudi Arabia).

But Saudi Arabia has also been the source of > 80% (n=2218) of all known MERS-CoV cases, and after a 5 year lull, we are seeing a noticeable uptick in human cases reported during the first 5 months of the year (see WHO: Saudi Arabia Reports 9 New MERS-CoV Cases). 

Today we have an open-access editorial, published this past week in the Journal of Epidemiology & Global Health, by Al-Tawfiq & Memish on the recent surge in cases in KSA, and the importance of healthcare preparedness and surveillance. 

This is  a relatively short review, but it reminds us that the threat from MERS-CoV has not gone away, and that asymptomatic (or mild cases) may contribute to the silent spread of the virus.  

I've only posted some excerpts, so follow the link to read the article in its entirety. I'll have a bit more after the break. 

Recurrent MERS-CoV Transmission in Saudi Arabia– Renewed Lessons in Healthcare Preparedness and Surveillance

Editorial Open access

Published: 02 June 2025

Volume 15, article number 77, (2025)

Jaffar A. Al-Tawfiq & Ziad A. Memish  

The World Health Organization (WHO) had recently announced on May 12, 2025, the reporting of nine new laboratory-confirmed cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in Saudi Arabia [1]. This announcement is a sobering reminder that while the global community remains focused on emergent threats like avian influenza or post-pandemic resilience, endemic zoonotic diseases like MERS-CoV may continue to circulate, evolve, and exploit gaps in infection prevention.

MERS-CoV, first reported in 2012 [2], is a betacoronavirus endemic to the Arabian Peninsula. Dromedary camels remain the primary animal reservoir. Though zoonotic transmission dominates most spillover events, human-to-human transmission—particularly in healthcare settings—has triggered multiple nosocomial clusters, sometimes involving a large number of cases. Notably, outbreaks in 2014 (Saudi Arabia) and 2015 (South Korea) underscored MERS-CoV’s epidemic potential when detection, triage, and infection control measures faltered or other patients characteristics predominate [3]. The number of cases had decreased significantly in the last few years (Fig. 1), with the highest number of cases in 2014.

Between February and April 2025, nine laboratory-confirmed MERS-CoV cases were reported in Saudi Arabia, primarily from Riyadh. Two elderly, non-healthcare individuals died following symptomatic illness, while a third recovered. The remaining six cases, all healthcare workers aged 18–65, were linked to secondary exposure from one index case. Five of them were asymptomatic and not hospitalized, highlighting the risk of silent transmission (Table 1) [1]. This cluster underscores the critical need for early detection, contact tracing, and strict infection control measures, especially in healthcare settings. The first multi-hospital MERS-CoV outbreak was controlled with basic infection control measures [4].

          (SNIP)

MERS-CoV’s case-fatality rate remains disturbingly high—approximately 35%—making every missed opportunity for containment a gamble with lives. The clustering of cases in early 2025, involving asymptomatic transmission, healthcare settings, and camel contact, is not new—but that’s precisely the concern. We’ve been here before.

MERS-CoV persists due to multiple factors and the complex human-animal interactions and at times due to wanes in the absence of crisis headlines. The continues zoonotic risks should be further explored from various aspects to prevent the spillover and to reawaken global stakeholders to the realities of persistent zoonoses. Surveillance must be strengthened, IPC rigorously enforced, and frontline workers empowered with knowledge and protection.

(Continue . . . )

 

While MERS-CoV hasn't managed to acquire the kind of transmissibility that made COVID a household name - we've seen large MERS-CoV outbreaks - particularly in crowded hospitals (see  Ziad Memish: Two MERS-CoV Hospital Super Spreading Studies).

Coronaviruses are highly mutable, and have the potential to recombine into new variants, which raises concerns over the co-circulation of MERS-CoV along with COVID, and other coronaviruses (see Nature: CoV Recombination Potential & The Need For the Development of Pan-CoV Vaccines).

While MERS and SARS get most of our attention, over the years we've looked at a number of non-MERS/SARS coronaviruses with zoonotic potential that are often found in bats, swine and even cattle.  A few (of many) examples include:

• 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 over two weeks ago, in J. of Infection: Novel Coronaviruses Identified in Livestock we looked at a warning from Chinese researchers on risks of livestock-borne coronaviruses.

Not so very long ago, 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).

Despite this painfully gained knowledge, most countries have elected - for political or economic reasons - to scale back on their surveillance, reporting, and preparedness efforts. 

While I can't tell you what emerging disease will spark the next pandemic - or when - it is all but guaranteed to happen again.  And when it does, we'll regret every day we squandered not aggressively preparing for its arrival.