H5N1 Cluster Concerns in Fayoum Egypt
Recombinomics Commentary 20:36
March 9, 2008
The case is an 8-year-old male from Etsa District, Fayum Governorate. He was hospitalized on 3 March 2008 in Fayum Fever Hospital and his first sample was negative and the second sample in 6 March 2008 was positive (the new regulation of the Ministry of Health and Population since December 2007, if the first sample was negative the patient remain hospitalized for second sample in day 3 of hospitalization). He was confirmed as being infected with A (H5N1) by the Ministry of Health and Population Central Public Health Laboratories on 7 March at 9:30 pm and NAMRU-3 on the 8th.
The above comments from the WHO Eastern Mediterranean update provide more detail on the most recently confirmed H5N1 case in Egypt. Like the 45th case (25F), the location of the recent case is in the Foyoum governorate, about 5 miles from the city of Fayoum. The confirmation of the two cases cause concerns because of the similarities in time and location. The cluster concerns are increased by media reports indicating the sister of the earlier cases, as well as the brother of the most recent case, also have bird flu symptoms.
Confirmation of clusters in Egypt is rare, although the number may rise because of more extensive testing which generated a positive result in the most recent cases, even though the initial test was negative. The largest confirmed cluster to date in Egypt was the Gharbiya cluster which involved three fatalities in one family. H5N1 was isolated from two of the cluster members, and both sequences had two receptor binding domain changes, V223I and M230I. The same two changes were found in poultry from Gharbiya and Beni Suef last season.
This season, isolates most closely related to the Gharbiya chicken sequence were isolated. In addition to the two receptor binding domain changes, the isolates also had the HA cleavage site first identified in the Guangdong goose in 1996, RERRRKKR. Last season M230I was associated with fatal infections in two additional cases. Thus, all patients infected with H5N1 containing M230I died.
The sequences from the patients infected at the end of last year, or the more recent patients this year have not been released. However, all of the cases confirmed this year have had pneumonia, in marked contrast to patients confirmed at his time last year, who have mild H5N1 (only one in seventeen died).
This latest cluster of two confirmed and two suspect H5N1 cases in Fayoum is cause for concern. Release of the H5N1 sequences from these patients would be useful.
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