12 February 2007
WHO Reports on 251
Persons with H5N1 Infection (2003-2006) and Confirms First Patient in Nigeria
(2007)
The World Health
Organization (WHO) 9 February issue of the weekly epidemiological record (WER)
contains a detailed update on 251 WHO laboratory-confirmed patients with H5N1
avian influenza A infections from 25 November 2003-24 November 2006. On 3 February the WHO also confirmed the
infection of the first patient in Nigeria (Lagos) with H5N1 virus infection.
The patient in Lagos, Nigeria’s largest city, was a 22 year-old woman who died on 16 January 2007. The definitive source of her infection is still under investigation. The 10 Feb 2007 issue of the International Herald Tribune carries an Associated Press article cites Tony Forman, the leader of the U.N. (FAO) team of experts assisting the Nigerian investigators, as attributing the human infection to exposure to a chicken purchased in a live bird market in Lagos just before Christmas. The young woman’s 52 year-old mother died on 4 January of similar flu-like symptoms, but tests for H5N1 have so far been negative for H5N1 infection, as have tests on other close contacts of the 22 year old patient.
Nigeria is the 11th
nation to report lab-confirmed H5N1 avian flu infections in humans. The total number of lab-confirmed human
infections with this virus is 271 of whom 165 (61 %) have died. The newspaper
“Vanguard” published a report online on 5 February, by Chioma Obinna, stating
that new outbreaks of H5N1 virus in avian populations have occurred in the
states of Edo, Kwara, and Sokoto with at total of 17 states in Nigeria
(including Lagos) having reported past H5N1 infections.
The WHO update
summarizing clinical and epidemiological data on the initial 251 lab-confirmed
patients with H5N1 influenza A virus infection contains 6 tables and 5 figures.
Examples of the important findings include:
A: The overall case
fatality rate was 60%.
B. Four days was the
median time from symptom onset until hospitalization.
C. There was no
statistical difference in median duration from symptom onset until
hospitalization between persons who lived and those who died.
D. The media time
from symptom onset until death was 9 days.
E. The median age was 18 years, with 52% of the
256 patients < 20 years and 89% < 40 years of age.
F. The gender ratio
of cases was 1.0 (129 males/127 females).
March 19-21, 2007 the
WHO will hold its 2nd consultation on clinical aspects of human
infection with H5N1 virus, in Antalya, Turkey.
Daniel R. Lucey, MD,
MPH
Director, Center for
Biological Counterterrorism and Emerging Diseases, EROne Institute, Department
of Emergency Medicine
Washington Hospital
Center
Adjunct Professor of
Microbiology and Immunology
Georgetown University
Medical Center
Washington, DC
E-mail: Daniel.R.Lucey@Medstar.net
Website:
www.BePast.org