Thursday, September 26, 2013

Memorializing the First Confirmed Case of A(H7N9)

Since February 2013, a novel avian influenza virus, A (H7N9), has infected more than  130 individuals in the People’s Republic of China and Taiwan. At least 44 of these infected individuals have died.  In a current article in the journal Respiratory Care, Chinese medical specialists report on the case-patient details of the first officially confirmed case from March 2013.[1]  Even with treatment, The 87-year-old man died a few days after admission to the hospital on March 4, 2013.
The authors state

 . . . we identified the world’s first human case of avian influenza A H7N9 virus infection. When we first admitted this patient, there were no health care guidelines that we could follow. Even in the absence of a definite diagnosis of influenza infection, we actively carried out isolation protection in accordance with the  standard  hospital  infection-protection  protocols  while  closely coordinating the activities of different departments and ensuring the protection of the medical  supplies.  In  addition,  we  organized  the  training  for  respiratory  infectious disease  protection  in  the  nursing  department.  We  believe  that  first-line  health  care providers  should  be  highly  aware  of  the   appropriate  infection-prevention  measures before  determining  whether  the  pathogen  has  the  capability  for  human-to-human transmission.

This individual is a member of a family cluster identified as the Shanghai Family Cluster.[2]   The two sons of this man were retrospectively reported as a confirmed and suspected case. Based on the onset dates, the son who died on February 28th may have been the index case in this cluster.

Each novel disease outbreak starts with an officially confirmed initial case. If A(H7N9) becomes a pandemic virus, the article in  Respiratory Care will be one of the first footnotes in a future history of such a pandemic.

Thursday, September 19, 2013

A MERS-CoV Cluster Outbreak in Medina, Saudi Arabia

Since August 28, seven cases of Middle East respiratory syndrome coronavirus (MERS-Cov) infection have been reported from the city of Madinah (Medina) by the Kingdom of Saudi Arabia Ministry of Health. Only minimal information about these cases has been provided in media statements.  The table below presents the information on these seven cases. Several have had contact with previously confirmed cases. Three individuals have died. Two individuals including one healthcare worker are reported as asymptomatic. And two individuals including the first reported case from Medina are still being treated.  Although it is possible that the initial case, the 55M, may have died and is double counted and reported as Case 2 in the table below. It is difficult to reconcile this case list with unconfirmed media reports from September 7 of  a doctor’s death in Medina. [1]

Without more information, it is not possible to speculate whether there is one or more clusters, and whether or not these are family clusters or clusters of nosocomial infection.


Wednesday, September 18, 2013

Recent MERS-CoV Sequences from the Kingdom of Saudi Arabia

At Epidemic - Molecular Epidemiology and Evolution of Viral Pathogens, Andrew Rambaut has compiled a list of 21 recently reported sequences of the Middle East Respiratory Coronavirus (MERS-CoV) from the Kingdom of Saudi Arabia (KSA).[1]

Lacking age and sex, and only having the collection date makes it difficult to correlate the sequence samples with previous, individually identified cases in the KSA. For provinces and cities in KSA that have only a few reported MERS-CoV cases, correlation of the sequences with individual cases is straight forward as the sample name is a clue to the geographic location. 

For several of the recently released sequences, case information is provided below. 

Bisha_1_2012 is likely from the 60-year-old-male from the town of Bisha in Asir Province. He experienced onset on June 6, 2012, was hospitalized on June 13, 2012 and died on June 24, 2012. He is not reported as part of any cluster of cases. 

Riyadh_1_2012 is likely from a retired 70-year-old male from Riyadh who is reported to have experienced onset on October 5, 2012, was hospitalized on October, 13, 2012 and died on October 23, 2012. He is one of two individuals reported as a family cluster (see Riyadh_2_2012 below).

Riyadh_2_2012 is likely from a 39-year-old male factory worker from Riyadh who is reported to have experienced onset on October 24, 2012, was hospitalized on October 28, 2013 and died on November 2, 2012. He is possibly the son of the individual who represents sample Riyadh_1_2012.

Riyadh_3_2013 seems to be a sample collected in February of 2013 from one of three brothers from Riyadh who were infected with MERS-CoV. All three brothers lived in one large house with 10 other adults. The 51-year-old male was being treated in a Riyadh hospital when he apparently experienced onset from MERS-CoV on February 13, 2013.  He died on February 24, 2013. This cluster of 3 cases is reported in the September issue of the International Journal of Infectious Diseases.[2] Apparently only two household members, two  brothers of the index case, were infected, a 39- year-old and a 40-year-old.  The 39-year-old died on March 2, and the other individual recovered. 

WHO confirmed the 39-year-old in an update published on March 12, 2013.  The 40-year-old was reported by WHO on March 23, 2013 as a recovered individual who had contact with a previous case (his brother[s]).  The 51-year-old male was not reported by WHO until August 28, 2013.  WHO did not identify these three cases as a family cluster. 

Buraidah_1_2013 may possibly be from a 63-year-old male from the city of Buraydah in Al-Qassim Province.  The collection date for this sample is May 13, 2013, however, the man is reported to have been hospitalized on May 15, 2013 and died on May 20, 2013. He is not reported as part of a cluster of cases and no other MERS-CoV cases have been officially reported from Al-Qassim Province in May 2013.   If there are no reporting errors in the collection date or the dates of hospitalization and death, then there is one additional unconfirmed, unaccounted case from Al-Qassim Province. 

Hafr Al-Batin_1_2013 is likely from a 21-year-old male from the town of Hafar Al-Batin, in the Eastern Province. This case was reported in June 2013. He is not reported as part of a cluster of cases.

Al-Hasa Sequences

A large outbreak of MERS-CoV cases occurred in April and May 2013 in the Eastern Province of KSA. [3] At least 24 individuals were confirmed cases and about half of them died. Most of infections occurred in nosocomial settings in the city of Al-Hofuf (also referred as Al-Hasa), although some cases were reported from a regional hospital more than 160 km away. 

Without more details about the sequences it is not possible to associate any Al-Hasa sequence with any specific individual from this outbreak. However, the reported collection dates for the Al-Hasa samples all fall after May 2, 2013. So it is unlikely that any of these sequences are from the 5-6 individuals in the cluster who died before May 2, 2013. 

It is not clear how representative these sequences are for the range of MERS-CoV infections in the KSA. 

Wednesday, September 11, 2013

MERS-CoV Outbreak Map – September 11, 2013

The eight countries reporting Middle East respiratory syndrome coronavirus (MERS-CoV) cases through September 11, 2013 are color coded by frequency of reported cases in the map below.  The numbers presented for all countries, with the exception of Saudi Arabia,  are presumed to be accurate.  The count from Saudi Arabia is uncertain due to poor case reporting from the Saudi Arabia Ministry of Health.  The local cluster outbreaks in the countries of France, Italy, Tunisia, and the United Kingdom are a result of the human-to-human infection. In each of these country clusters, the index case had recently returned from a trip to the Middle East. 

  World map of MERS--CoV cases as of September 11, 2013.

It Is Not Too Soon to Develop a MERS Vaccine

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is spreading throughout Saudi Arabia. The first known human infections of MERS-CoV occurred in 2012 in Jordan in a hospital setting.[1] Since then, more than 130+ suspected and confirmed cases have been recorded from eight countries in Europe, Africa, and the Middle East. More than 100 cases (about 80% of all cases) have occurred in Saudi Arabia.  More concerning is that the number of cases is increasing rapidly in Saudi Arabia. In the last two weeks the Saudi Arabia Ministry of Health has reported about 25 new cases.[2]

Most of these new cases in Saudi Arabia appear to have been infected by human-to-human contact. It is time for public health officials to be proactive and support plans for developing a MERS-CoV vaccine. Spanish researchers have taken the first step and report that they are working towards developing a MERS-CoV candidate vaccine.[3] More MERS-CoV vaccine research is needed immediately, just in case.

h/t Giuseppe Michieli