Wednesday, June 25, 2014

Updated Map Showing the General Locations of MERS-CoV Cases on the Arabian Peninsula (June 25, 2014)



Current map of the general geolocations of more than 700 local MERS-CoV infections on the Arabian Peninsula as of June 25, 2014. Location names are labeled in red. The area of the circle depicts the relative number of reported cases at that location. 

 
Map note: On June 3, the Saudi Arabia Ministry of Health announced more than 100 additional MERS cases that occurred between May 2013 and April 2014 (link).  No geographic information about these cases was provided by the Ministry of Health and they are not included on this map. Previous map, April 21, 2014 here.

Thursday, June 19, 2014

Discrepancies in the World Health Organization’s Count of MERS Cases in Saudi Arabia



With Saudi Arabia reporting more than 80% of all Middle East Respiratory Syndrome (MERS) cases to date, detailed information about the individual cases from Saudi Arabia is critical to understanding the nature and spread of this novel disease. There are some discrepancies among the MERS cases reported by World Health Organization (WHO) from Saudi Arabia. Of course, WHO is constrained by the quality of data provided by its various member states.

Generally, WHO provides detailed information on the initial cases of a novel disease outbreak in its online publication, Disease Outbreak News (DON). The first WHO report of a MERS [novel coronavirus] infection was published on September 23, 2012. Between September 2012 and April 16, 2014, WHO reported details on 228 MERS cases with varying levels of details provided by the reporting member states. Of the 228 cases reported by WHO though that date, 181 were individually reported cases from Saudi Arabia. The DON of April 14, 2014 (15 reported cases from Jeddah and Riyadh) was the last Saudi Arabian case-by-case report from WHO. After that date, WHO only provided aggregate case totals from Saudi Arabia. These aggregate totals were embedded in 6 DON reports between May 7, 2014 and June 13, 2014 as noted in the table below.

On June 13, 2014, WHO provided a summary of these aggregated cases. According to WHO, 402 cases were summarized. However, a tally of the WHO totals from the previous DONs indicates that only 401 cases were actually aggregated. A comparison of the WHO total with media reports from the Saudi Arabia Ministry of Health indicates that 404 MERS cases were publicly reported by the Ministry of Health.

For the period between April 11, 2014 and May 4, 2014, WHO reports 229 cases from Saudi Arabia, although the Saudi Arabia Ministry of Health only publicly reported 228 cases during that period. One possible explanation is that the 51 one-year-old individual from Riyadh reported on April 9, 2014 by  the Saudi Arabia Ministry of Health (link FluTrackers case # 227), not previously enumerated by WHO, was added to the aggregate total (see: link). Also,  between May 5, 2014 and May 9, 2014 Saudi Arabia Ministry of Health reported 62 MERS cases. During this same period WHO only reported 58 cases in aggregate (see: link). It is possible that WHO failed to incorporate four cases into its cumulative tally for this 5-day period in Saudi Arabia.

With the reporting of specific case details of two individuals from Saudi Arabia in DON on June 16, 2014,  WHO has now apparently returned to reporting individual case details from Saudi Arabia. Better individual case details may again be flowing from Saudi Arabia to WHO.

Depending on the quality and accuracy of the data provided by Saudi Arabia, a discrepancy of 3 or 4 cases among more than 500 reported cases falls within a reasonable error factor. Such differences will not appreciably affect interpretations or speculations drawn from such a large sample of cases.

Of more serious concern is a report on June 3, 2014  by the Saudi Arabia Ministry of Health indicating retrospective reporting of more than 100 additional MERS cases in Saudi Arabia (and acknowledged by WHO - link) going back to May 2013 (See: The Saudi Arabia Ministry of Health Quietly Announces an Additional 113 Cases of MERS). This means that from May 2013 through April 2014, about 15% of all MERS cases in Saudi Arabia were unreported. A 15% error factor is unacceptable when public health officials and the rest of the world are trying to understand the nature of a novel infectious disease with a high fatality rate.
 

Tuesday, June 3, 2014

The Saudi Arabia Ministry of Health Quietly Announces an Additional 113 Cases of MERS


Today, the Ministry of Health (MOH) officials in the Kingdom of Saudi Arabia (KSA) revised upward the number of Middle East Respiratory Syndrome (MERS) case and MERS-related deaths that have occurred in the KSA (link). As noted by Michael Coston (link), the KSA MOH added a total of 113 cases and 92 deaths to the official cumulative count from that county. The lack of any details for these additional cases or the individuals who died, precludes determining whether all of the unreported deaths are only from the previously unreported cases. In several instances in recent MOH media reports, there have been reported deaths that could not be correlated with previously reported cases because the combination of age/gender of the reported deaths from a specific location could not be associated with previously reported cases (link, link).

Through yesterday, publicly reported cases from the KSA represented about 82% of all MERS cases reported from around the world. Today, with these additional reported cases, the KSA lays claim to about 85% of all cases, not including the 20 infected cases that have been exported to at least 12 different countries. Without doubt, the nexus of worldwide MERS infections is the KSA.

This revelation of previously unreported cases by the KSA MOH ought to be disconcerting. A review of the graph associated with the report indicates that a few of these unreported cases go back as far as May of 2013. There are two possible conclusions about the delay in reporting these case by KSA MOH.  The fact that these cases are only now being publicly and officially reported could suggest that the MOH has been purposefully withholding information about these MERS cases since May of 2013.

Or, maybe the KSA MOH has been so overwhelmed by this outbreak, that they have only now been able to go back and sift through their data to find these additional cases. Either way, the announcement today, with no details or explanations, reflects negatively on the KSA MOH and their ability to track the MERS outbreak within their country.

Monday, May 19, 2014

The First 2014 MERS Wave Peaked in Late April



About three week ago, I posted a graph that suggested the first wave of Middle East Respiratory Syndrome (MERS) infections in 2014 peaked about April 20th and was starting to decline (Number ofCurrent MERS Infections on the Arabian Peninsula May Be Declining).

Since April 30 almost 200 additional MERS cases have been reported. Extending the graph to include data through May 17, the additional data clearly show that the number of MERS cases (based on the plotting criteria) started to decline about April 20 and has continue to decline since then. The date associated with each individual case varies with the publicly available information. Where possible, the onset date is used. If the onset date is not provided, the date of hospitalization is used or the date of death. If the case is asymptomatic, the date of confirmation is used if available, if not, the date of the official report is used. If no other calendar information is available, the date of the report is used.  Importantly, the distribution of these additional cases by onset date, hospitalization or death date, or date of report, did not appreciably alter the shape of the graph or shift it closer in time. The plotted 5-day central moving average (incorporating all of the additional cases) is almost coincidental with the moving average plotted through April 30 as show on the graph below. 




Since most MERS cases are being reported from Saudi Arabia, the decline in cases is welcome news.  However, the number of exported MERS cases from Saudi Arabia to other countries seems to be increasing and should of concern for public health officials worldwide.