H5N1 Confirmation in Fatal Cairo Teenager Case
Recombinomics Commentary
April 11, 2007
Case number 34
Reported on 8 April 2007 This case is a female adolescent, 15 years old from Cairo Governorate. Date of onset of illness was on March 30. She was hospitalized into Abbasya Chest hospital on the 5th of April and the sample was taken on the 7th. It was confirmed positive for H5N1 in both MOH (7 April) and NAMRU-3 (8 April) laboratories. At the beginning, the patient denied exposure to sick poultry from the market one week before the onset of symptoms.
She died on April 10 at 7:30 pm at Abbasya Chest Hospital due to respiratory failure resulted from bi-lateral pneumonia.
The above details on the latest confirmed case in Egypt detail the differences between this case and the recent mild cases in central and southern Egypt. The initial cases this season in Egypt were confirmed in late 2006 and were from the Gharbiya governorate and all four were fatal. Sequences were generated from three of the cases and all had M230I, a change adjacent to the receptor binding domain which matches human strains (H1N1, H3N2, influenza B).
This change was in the last fatal case prior to the case in Cairo, and was also in a chicken isolate from Gharbiya in February, 2007. The poultry isolate shared a number of polymorphisms found in the Gharbiya cluster, including HA M230I and V223I, although Tamiflu (oseltamivir) resistance (N294S) was not found in the chicken isolate. However, the sequence had mixed signals at a number of positions indicating the chicken was infected with multiple strains of H5N1. Plaque purification of this isolate would be required to rule out N294S.
The latest case, like the earlier cases developed bi-lateral pneumonia in spite of Tamiflu treatment. The sequence of the isolate would help determine if the treatment failure was due to the time lag between the disease onset and treatment, or was due to genetic changes such as HA M230I or NA N294S.
The linkage to poultry a week before the onset of symptoms is also unclear because of the time lag. More poultry sequences from the Cairo area would be useful.
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