Wednesday 28 August 2013

Dr Ziad Memish discusses MERS in the Kingdom of Saudi Arabia (KSA)

Insights from the Front Lines. UPMC Center for Health
Security presentation by Dr Ziad Memish on MERS-CoV.
August 21, 2013
University of Pittsburgh Medical Center (UPMC) Center for Health Security recently organized a seminar by Dr Memish in which he discusses the Saudi experience with the Middle East respiratory syndrome outbreak. 

Dr Memish, is among the most important health professionals in the world on this topic and he is located at the front-line of understanding the behaviour of this new virus and its ongoing outbreak in humans.

I've distilled some quotes (with some of my additions in brackets) and points that I found interesting during his 30-min presentation:
  • In addition to his many awards and roles in consultancy and medicine (including roles as Deputy Minister of Health for Public Health (KSA), Director for WHO collaborating centre for Mass Gathering Medicine; consultant for infectious diseases at King Fahd medical city, Faculty of College of Medicine at Alfaisal University/King Saud University/Emory University/Liverpool School of Medicine and on committees (Executive Board of the WHO), Dr Memish also has >300 peer-reviewed publications and chapters. I recently summarized a few of the MERS-CoV-related ones here.
  • Dr Memish and the KSA Ministry of Health (MOH) have a "huge public health team" investigating the new virus (currently 96 cases and 47 deaths worldwide; 76/39 in KSA)
  • More and more mild and symptomatic cases being detected - more extensive testing on contacts
  • Healthy and well MERS-CoV infectees do better than those with underlying conditions
  • Dr Memish saw the Prof Ali Zaki report of the first MERS-CoV case in Bisha/Jeddah, on his Blackberry, and an MOH team was then immediately dispatched and communication with WHO, CDC, Columbia University and the EcoHealth alliance to work with the KSA MOH including extensive investigation of at least 29 family members and 100 employees in Bisha and the hospital in Jeddah - none of whom were MERS cases (around 7min in the video)
  • Reminder of the 2002/2003 8,098 probable SARS-CoV cases and 774 deaths over 5-7-months, costing the economy >$30-billion. SARS differs from MERS in the lower proportion of cases of severe disease linked to an underlying condition
  • Between Jan and end of July - there were close to 8-million umrah visitors. The month of Ramadan had almost 15-million people perform the hajj (5-million from outside KSA)
  • We think there is a some sort of pre-existing genetic underlying disease predisposing to MERS; based on studies of family clusters (late 18min)
  • The Al-Ahsa hospital cluster
    • Al-Ahsa represents 25% of the area of KSA; population 1.3-million
    • No increase in mortality, but local infection control team noted a shift in mortalities from the "usual" causes towards pneumonia 
    • The hospital cares of the elderly (a geriatric hospital)
    • Very good documentation at this hospital which helped track infection
    • Had to stop shared transport (ambulance) system for dialysis patients coming to hospital, stopping  those with suspected disease from coming to the dialysis unit, enhancing cleaning and excluding visitors and non-essential staff
    • 10/30 had animal exposures of any sorts (birds, bats, camels, cats etc). Hard to get families to recall exposures-problem for animal source tracking.
    • Lesson learned include
      • MERS-CoV can causes healthcare-associated infections
      • Early symptoms of MERS can be mild and non-specific and can be missed
      • 1/3 of patients have gastrointestianl symptoms
      • Human-to-human transmission does occur but how is not clear
      • Droplet and contact precaution are essential
      • Don't know if asymptomatic but MERS-CoV PCR positive patients can transmit virus
      • PCR is the gold standard testing method
      • Deeper airway samples give better results - repeat sampling required if negative on first sampling, when MERS is clinically suspected
  • Collaborating with international groups (CDC, NIH etc) to standardise and validate antibody testing methods
  • Potential sources includes dates, bats, livestock, stray cats and dogs, pet birds and camels (antibody-positive in Oman despite absence of human cases there)
    • >1000 bat samples collected but relationship between bats and patients is undocumented
  • Transmission routes include:
    • Sporadic community cases with non-human exposures (animals or environmental)
    • Family clusters
    • Healthcare clusters
    • Travel-related/workplace transmission
  • Clinically, MERS-CoV can cause severe disease on older, immunocompromised patients, those with underlying conditions, and primary index cases but also causes mild or asymptomatic disease in the previously healthy, young and secondary cases; most HCW infections were in teh young and healthy. Standard acute (48-hour) fever and myalgia in the healthy cases.
  • Risk for HCWs was related to invasive procedures (see WHO IPC linked and discussed in previous post on this). Diabetes and obesity is relatively high in KSA so need more cases to determine risks.
  • Looking at therapeutics that have and have not worked for SARS infections
  • MOH website adds cases daily at 5 o'clock
  • Reservoir needs to be determined
  • Sample type, false negatives and lack of serology are diagnostic challenges
  • MERS-CoV has limited transmission
In follow-up questions, Dr Memish noted that the first the KSA MOH knew of the new CoV was when they read Dr Zaki's eMail to ProMED. Since then, surveillance testing of anyone at key sites, with pneumonia admitted to an intensive care unit was extrapolated post-hajj 2012, to all of the KSA. Other patients can get tested. MERS-CoV testing is centralised - 3 KSA labs now test, 24/7.

70 suspected cases are reported per day. Most testing is on those who are hospitalised.

The KSA is working with Sanger Institute in the UK for sequencing. All samples are being sent there. Not every case yields a full genome (real-time PCR threshold cycle values >30-35 may fail). 21 more genomes are being finalised-coming out in the next few days-to add to the existing 9. KSA also works with other institutes worldwide and it seems that local capacity for virus discovery and genome sequencing is lacking at this stage. This means delays due to forging new international alliances and in getting materials out of the KSA and into other countries, with strong biohazard importation borders to cross and regulations to satisfy, will probably continue. But things should speed up as the process becomes more familiar to all parties.

Dr Memish, supporting comments he has made previously, still suspects that other countries both in the region and globally, would find more MERS-CoV cases if they looked as hard and as proactviely as the KSA is doing. 

At around 48-40min Dr Memish made an important comment about epidemiology:

Epi 101. If you don't look for something you will not find it. You have to look for the disease and if you're not testing and you are not doing anything you will not pick it up.

I only got to 50-min, so feel free to follow the link and hear more. 

A great summary of the situation so far from the country at the center of the emergence of this new virus.

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