Published Date: 2003-03-27 23:50:00
Subject: PRO/AH/EDR> Avian Influenza, human - Netherlands (08)
Archive Number: 20030327.0762
AVIAN INFLUENZA, HUMAN - NETHERLANDS (08)
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Thu 27 Mar 2003
From: ProMED-mail <email@example.com>
Source: Eurosurveillance Weekly, Thu 27 Mar 2003, Volume 7 / Issue 13 [edited]
Human Infection Associated with Outbreak of Fowl Plague (Avian Influenza)
in The Netherlands: Update as of Thu 27 Mar 2003
At the beginning of March 2003 an outbreak of highly pathogenic avian
influenza (A/H7N7) in several Dutch poultry farms was reported (1). On Tue
11 Mar 2003, several workers who had been exposed to A/H7N7 infected
poultry developed conjunctivitis. Some of them tested positive for
influenza A/H7N7 (2). One week later, 2 close contacts of a worker with
H7N7 infection developed similar eye symptoms. They had also been infected
with the avian influenza virus, although they had no exposure to infected
poultry themselves, which strongly suggests human-to-human transmission of
the virus (3).
The latest enhanced surveillance (up to Wed 26 Mar 2003), established by
the Centre for Infectious Disease Epidemiology (RIVM) in collaboration with
a multi-organisation partnership, has identified 247 persons with acute
health problems among the population exposed to infected poultry. Of these,
194 had conjunctivitis, 17 had influenza-like illness (ILI) only, and 36
reported other symptoms such as diarrhoea, and nausea. Of the 194 persons
with conjunctivitis, 35 also reported ILI.
Of the 247 patients, 65 (26.3 percent) have tested positive for influenza
A/H7N7, 5 were influenza A/H3 positive, 137 were influenza virus negative,
and in 40 results are pending. Of 194 patients with conjunctivitis, 169
test results were available, 61 had conjunctival swabs positive for H7N7
(36 percent), and 4 had throat swabs positive for H3 (2 percent). 4
patients with positive H7N7 results had unknown or other (no conjunctivitis
or ILI) symptoms. No additional contacts, besides the 2 already mentioned,
have been reported A/H7N7 positive.
No double infections with influenza A/H7N7 virus and A/H1 or A/H3 influenza
viruses have been found. Co-infection with both human and avian influenza
virus could potentially lead to a reassortment of both viruses and result
in a new pandemic.
Since Thu 13 Mar 2003 there has been a fall in the number of reported
conjunctivitis patients (the total number, as well as the number and
proportion of H7 infections). This decline may be due to control measures,
e.g., wearing protective glasses, mouth masks, and improved personal
hygiene that were implemented around that time. The drop in the number of
H7 infections after 20 Mar 2003 coincides with the implementation of
oseltamivir prophylaxis, which became obligatory for all workers on 14 Mar
2003, although it is too early to suggest a causal relationship. The
enhanced surveillance continues.
(1) Ministry of Health, Welfare and Sport, The Netherlands. Ruimer pluimvee
besmet met vogelpestvirus (press release) 11 Mar 2003.
(2) Fouchier R, Koopmans M, Meijer A, Wilbrink B, van Wijngaarden J,
Osterhaus A. Avian Influenza, human - Netherlands. H7N7 Conjunctivitis;
human. ProMED mail posting, 11 Mar 2003 [see: Avian influenza, human
- Netherlands 20030311.0594].
(3) Meijer A, Du Ry van Beest Holle M, Fouchier R, Natrop G, Wilbrink B,
Bosman A, et al. Outbreak of fowl plague (avian influenza) leads to
secondary human cases, March 2003, the Netherlands. Eurosurveillance Weekly
2003; 7: 030320.
(By A. Meijer 1, M. Du Ry van Beest Holle 2, 3, R. Fouchier 4, G. Natrop 5,
B. Wilbrink 1, A. Bosman 2, 3, A. Osterhaus 4, J. van Steenbergen 6, M.
Conyn-van Spaendonck 2, M. Koopmans 1
1 National Institute of Public Health and the Environment (RIVM),
Diagnostic Laboratory for Infectious Diseases and Perinatal Screening
2 RIVM, Centre for Infectious Disease Epidemiology
3 European Programme for Intervention Epidemiology Training (EPIET),
4 Erasmus Medical Centre Rotterdam, Department of Virology
5 Municipal Health Service
6 Office of the National Coordination Structure for Infectious Disease Control)