#MERS Season’s Greetings?

Updated on March 23rd 2016

Four main information to be posted this month:

  1. The last WHO audit in KSA, noticing improvments and may be influencing performances in ICP by preventing nosocomial infection, so far.
  2. Almost all MERS cases are primary cases: difficult today to deny any connection with camels…and no outbreak. (see below)
  3. A Management of change regarding the way KSA is taking care of asymptomatic Mers-CoV tested positive for Camels and consequences
  4. To be noticed is the great improvement of Infection control prevention in health facilities: zero nosocomial case reported so far! Was wrong unfortunately; one nosocomial cluster in Buraidah.

Here we are in winter season; we observe reoccurence of Mers Cases in KSA; as a reminder a question has been raised about possible seasonality of MERS-CoV and so far not answered.

On December 16th 2015, one female,expat and HCW was reported ill in Buraidah; classified as secondary acquired…but by whom and where (nosocomial infection?)

On December 17th, a new Mers case reported in Najran; primary case of a Saudi, 48 y/old in a critical condition.

We shall have to pay attention in the coming days and to monitor the new cases in order to follow up the emergence of possible strain related to seasonality (?).

Mers and calves

Happy Holidays then return to business as usual?

Since January 1st 2016, 4 Fatalities in KSA

Symptomatic cases:

  • 34 primary cases in KSA, 32 secondary:
    • including 7 HCW (Jedah, Buraidah (4 asymptomatic?), Ryadh)
    • 29 cases in Buraidah since 2016=>nosocomial cluster:(26) + source of primary cases (2 for 2015/2016)

      -15 deaths (mortality = 52%)

      -6  HCW

      see Buraidah nosocomial outbreak

  • 2 primary cases in UAE,
  • 1 primary case in Qatar, the 1st recorded but coming from KSA.

Asymptomatic cases:

  • 8 secondary cases, expats, in KSA (near Jedah, Ryadh, Buraidah), including 3 HCW in Buraidah. I take the opportunity to point out and congratulate Saudia MoH for improving not only the daily reporting but to have launched a tracking of Mers cases whenever Mers-CoV identified in camels or during nosocomial infection. On the way to a pro-active management of Mers cases. Good point!
  • 2 household case in link with a previous symptomatic primary case.

Imported cases:

  • 1 case traveling from Oman to Thailand. More details here:

    On 24 January, the National IHR Focal Point of Oman was informed about the case for the necessary follow up on contacts back in Oman and investigation of history of exposure. Investigations revealed that the case had contacts with camels in the 14 days prior to the onset of symptoms. No epidemiological links have been established between this case and the latest case detected in Oman.

    Measures are being taken to trace all contacts of the cases in Oman, during his journey to Thailand, and within Bangkok.

All are in close contacts with camels, not HCW. Interesting isn’t it?

But curiously, referring to the case reported on Dec.16th 2015, no other case has been reported…How did the HCW to be infected? By who and how? Good questions…poor answer.


See also “Stay away from young camels”

#MERS:Risks exposure & Risks factors in KSA

This week was posted the first case control study on MERS in KSA. Not really a surprise but new evidence on the key role of dromedary camels as the source and reservoir for MERS-CoV . Two main causes to explain the spread of MERS in KSA since 2012:

  1. Zoonosis: People indirect contact with camels are more exposed to get MERS; Camel herdsmen or slaughterhouse workers are mostly the primary cases.
  2. Nosocomial outbreak: People with underlying or pre-existing medical conditions like diabetes,cardiac or pulmonary failures,kidney disease or immuno-compromised are high risks to get MERS at the hospital whenever a lack of the infectious control protocol is occurring. Health Care Workers (HCW) are impacted but also responsible for this nosocomial outbreak.

MERS Risk Exposure and Factors_2015

 Regarding Epidemiology, this study brings up interesting data regarding the ratio primary/secondary MERS cases:

  • 6% are primary cases related to zoonosis; up to 56% died. This fatality rate is over the total MERS fatality rate around 42%.
  • 94% are secondary cases, human to human spread which occurs mostly at the hospital (Emergency room,ICU,renal dialysis) due to underlying poor medical conditions.

The flow chart above summarizes the different root causes, risk exposure and how risks factors are playing a key role in the outcome.

Risk factors of #MERS Coronavirus nosocomial infection

Recently a good question was raised by @gwendolbowling about the occurrence of a nosocomial infection in an university hospital, referenced as best of the class?


My first answer was to refer to a continous quality improvement process/PDCA wheel by including on a regular basis, health process audit and ICP inspection; as explained in another blog (Comprehensive understanding of nosocomial #MERS outbreaks), to track and check any critical point which might be responsible for a cross contamination leading to nosocomial infection.


There are different types of risk factors which contribute to trigger off a nosocomial infection:

  • Architecture:residential hospital preferable for admitting/treating infectious diseases
  • Logistics and hospitalization:a step by step inspection from supply (income), management of care (indoor) to waste management (outcome).

Noso Tab

It is always a multifactorial root causes tree which explains the occurrence of nosocomial infection.

screen prevention

Replace Malaria by MERS in the figure and you understand that several screens exist to prevent infection and each time one screen is missing then there is an increase of the infection risk leading to possible nosocomial infection. In other words, a lack of ICP is responsible for nosocomial outbreak.

By conducting an health process audit focusing on ICP, close to HACCP audit for water and food safety, it is possible to identify gaps, critical points and cross contamination risks due to lack of controls or absence of preventive measures (primary,secondary or tertiary).

What do we observe for MERS as a nosocomial infection leading to outbreak? It starts with one index case, infected outside the hospital (at home or workplace) who is admitted at the emergency room. He is waiting for a long time, sharing the overcrowded location with other ill people. As he is not identified as MERS carrier, HCW do not apply on a 24/7 the ICP by wearing adequate PPE; HCW become ill but also vector for spreading MERS infection to others, mostly by close contact (MERS is not an airborne disease), leading to an intra hospital outbreak: this is the chain reaction described in Nosocomial Mers outbreak in Riyadh.


But we have to consider that there are alternative ways to contaminate an hospital building and it is of great importance to audit the logistics process: what is going in (food, medical equipment/tools, linen) and waste management coming from infected patient, classified as bio-hazard with a specific way for elimination. Here we are talking also about hygiene and sterilization inside the hospital.


Cleaning, hand sanitazing, by insisting on specs related to MERS-CoV which can contaminate from fomites, some of them staying on sponges or rags for a while.

Implementing ICP is one thing; auditing and checking on regular basis that procedures are applyed and that performances show a low rate of nosocomial infection are the key values to prevent outbreak. Training, drills and performance review are part of the ICP.

At this stage, it is easier to understand why a nosocomial outbreak can occur even in the most famous international university hospital if there is one or multiple failures in the ICP. Zero nosocomial infection remains a day to day challenge.

Reference: Prevention of hospital-acquired infections A PRACTICAL GUIDE by WHO,2002

Towards a #MERS Vaccine? Who is the target?

Helen Branswell has recently published Camel vaccine against MERS could slow human to camel infections.

In its 10th meeting hold on september 3rd, IHR Emergency Committee of WHO addressed a couple of things related to vaccine:

WHO Statement on 10th meeting IHR/EC

  • International collaboration to develop human and animal vaccines and therapeutics should be accelerated.

Laboratories have launched their battle-field researchers in order to be the first to produce a vaccine against MERS; whatever the vaccine would be?


Since 2012, Virology and Epidemiology have brought on the table a lot of information about the virus itself, a coronavirus, same family of SARS virus.

As of today we know how MERS is operating as an infectious disease, hosted by dromadary camels mainly in Middle-East (>90% infected), starting by a zoonosis then spreading human to human through clusters in household or nosocomial infection in the hospitals.

Two kinds of infected (by Mers-Cov) population have emerged in KSA:

  • symptomatic:either elderly or People with underlying poor medical conditions or chronic diseases including but not limited to diabetes,chronic renal failure, cardio-respiratory diseases or immunosuppressed
  • asymptomatic:healthy carriers

Root causes,mitigations and prevention of MERS-CoV_2015

Identifying healthy carriers, asymptomatic ones is based on positive testing, sometimes in link with health risks exposure like camels herds owners, slaughterhouse workers, or health care workers (HCW). Even if prevalence is quite low, we have identified a life cycle for Mers infection and outbreaks (see chart).

It is not the purpose here to review the conditions for nosocomial outbreak at the hospitals; see: Follow-up of the nosocomial #MERS outbreak in Riyadh,KSA

Knowing that, how could we prevent MERS from spreading both at community hospital level and at household level? Would it be realistic to vaccine the entire KSA population or only People at high risks? Would such a vaccination program prevent actually MERS from spreading?

Or do we focus on the source of MERS Coronavirus, I mean dromadary camels and manly young calves under 5 years old? It would make more sense with a long lasting and sustainable outcome to prevent Mers coronavirus from jumping outside of animal to human; in other words to prevent a zoonosis?

The answer seems obviously understood in the question…KSA MOH is supporting and sponsoring the idea of an animal vaccine by working hard on this issue.

Once upon the time…#MERS Coronavirus

The kissOnce upon the time in a Middle-Eastern Kingdom, a new infectious disease appeared which looked like a Flu but more critical, remembering SARS a long time ago.

After a while and by using alternative ways, a new virus was identified in the family of the Coronavirus who is responsible for respiratory syndrome. It was called MERS CoV in reference to the first location: Middle East.

It was in 2012….

It took some time to learn more about this virus: where is it coming from? How is it spreading and infecting ?

As of today, virology brought on the table and media clear evidences with phylogenetics. Step by step, study after study, virology helped epidemiology to start understanding MERS CoV better and better.

  • Where does MERS CoV come from?

The coronavirus was previously hosted by bats then more recently move to camels in Africa, mainly horn of Africa before jumping to Middle East following camels herds and markets close to Jeddah port, the main region for importing camels from Africa (Soudan,Ethiopia,Somalia).

7.700 dromedary camels infected in KSA=3.3% of camel herds.

  • What is MERS?

MERS is a zoonosis, spreading recently from animal (camel) to human then from human to human under certain circumstances in link with environment and pre existing medical conditions.

Closed locations (confined space) like household or hospital ICU are known to spread infection. People with cardiac, respiratory or kidney failure, diabetic or immunosupressed disease are more subject and vulnerable to MERS.

The fatality rate is 40% based on recorded cases but might be lower around 20% of the entire infected population (see recent South Korea nosocomial outbreak).

  • How to get MERS?

As a zoonosis, the most likely way to get MERS CoV is by handling or touching camels, their milk, meat or urine. Once introduced in human being, contamination can occur by close contacts through droplets or fomites. Hygiene including hand washing and sanitation, cough etiquette or facial masks are key factors to prevent contamination.Key words MERS

Slaughterhouse workers exposed to infected camels (unlikely) have been infected at higher rate compared with non exposed population.

Difficult to fight cultural issues in an area where camels are beloved animals like cows are in India. How to inform, train camel herders, farmers from getting too close from young and juvenile calves? Because in addition to environtmental and health factors, there is another key factors for spreading the virus during childbirth at winter/spring season. Yes, there is a seasonal cycle for MERS outbreak!

Surprisingly, the second likely place to get coronavirus is at the hospital. Health care workers, patients hospitalized or their visitors have been exposed and contaminated leading to a huge and repetitive nosocomial outbreaks. At everytime a gap in the infection control prevention has been observed due to lack of knowledge and training.

Fortunately, human to human transmission is low with mostly two generations but no more. The recent outbreak in South Korea has demonstrated that one imported MERS case is responsible of 186 cases and 36 deaths. But most likely, one infected patient contaminates one or two People only.

So far, no treatment and no vaccine are available !

The only way to avoid spread of MERS CoV is by preventing contact between young calves and infected camels with human body. No more but no less…looking forward R&D of a vaccine (animal or human ?).

Time for One Health issue by combining veterinary and global health watching the emergence of new diseases and zoonosis.