http://www.eurosurveillance.org/ew/2005/050407.asp

E-alert 13 April: Worldwide laboratory distribution of influenza A/H2N2
virus similar to 1957-58 pandemic strain, labs asked to destroy all samples
immediately

Editorial team1 (eurosurveillance.weekly@hpa.org.uk), Adam Meijer2, Caroline
Brown2 and John Paget2

1Eurosurveillance editorial office
2European Influenza Surveillance Scheme co-ordination centre, NIVEL,
Utrecht, the Netherlands

An influenza A/H2N2 virus, similar to that which caused the 1957-8 influenza
pandemic has been inadvertently distributed in proficiency panels for
quality control assessment to at least 3686 laboratories in Canada and the
United States, and 61 laboratories worldwide, the World Health Organization
announced on 12 April [1]. The distribution occurred between October 2004
and February 2005.

The A/H2N2 virus concerned, A/Japan/305/57 H2N2, is the same strain of virus
that circulated during the 1957-58 influenza pandemic. The pandemic strain
was highly transmissible among humans, and continued to circulate in humans
causing annual epidemics until 1968, after which time it vanished. An A/H2N2
virus is not included in current trivalent influenza vaccines, and it is
thought that people born after 1968 have no immunity to A/H2N2 infection.

The virus was identified by a local laboratory in Canada and reported to the
Public Health Agency of Canada (PHAC, http://www.phac-aspc.gc.ca), which
informed WHO on 26 March. The PHAC immediately initiated appropriate
biosafety measures and respiratory surveillance and traced the source of the
virus to a panel of proficiency testing samples distributed by the College
of American Pathologists (CAP, http://www.cap.org). This information was
passed to WHO and the United States Department of Health and Human Services
(HHS) on 8 April. HHS has since learnt that additional A/H2N2 samples were
sent to additional laboratories in the US by other proficiency testing
providers.

On 8 April, the CAP, at the request of the US government, contacted all
laboratories participating in the proficiency testing and asked them to
destroy all samples containing A/H2N2 virus. On 12 April the CAP further
asked all the laboratories to send confirmation of the destruction, and to
investigate and notify national authorities of any respiratory disease seen
in laboratory staff.

WHO has the addresses of all laboratories involved and has passed these on
to the relevant ministries of health, requesting their collaboration.

The European Early Warning and Response System (EWRS) [2] today issued a
level 2 alert to the competent public health authorities in the EU, with the
information currently available from WHO. The European Commission is in
permanent contact with the member states concerned and WHO and is following
the situation closely.

The European Influenza Surveillance Scheme (EISS, http://www.eiss.org/) has
today issued an urgent questionnaire for all laboratories participating in
the Community Network of Reference Laboratories for Human Influenza in
Europe [2], with guidance. All laboratories in this network can detect the
A/H2N2 virus, but only 38% (12/32) of them currently have the reagents
available to identify the H2 subtype of the virus [2]. EISS is working with
laboratories to improve the detection of potential pandemic viruses,
including A/H2N2 viruses [2].

Based on virus detection, there have so far been no reports of any A/H2N2
infections in laboratory staff associated with this sample distribution.
When proper biosafety precautions are taken, the risk of laboratory-acquired
influenza infections is greatly reduced and the likelihood of any infections
in these staff and the general public is low.

WHO recommends that all proficiency panel specimens containing A/H2N2 be
destroyed immediately, and that biosafety procedures for influenza viruses
that are no longer circulating in humans be reviewed.



Countries in which at least one laboratory is currently known to have
received virus samples:

European countries:

Belgium
France
Germany
Italy



Other countries:

Bermuda
Brazil
Canada
Chile
Hong Kong Special Administrative Region of China
Israel
Japan
Lebanon
Mexico
The Republic of Korea
Saudi Arabia
Singapore
Taiwan
United States



Reference:

1. WHO CSR. International response to the distribution of a H2N2 influenza
virus for laboratory testing: Risk considered low for laboratory workers and
the public. Press release, 12 April 2005.
(http://www.who.int/csr/disease/influenza/h2n2_2005_04_12/en/)
2. Commission decision of 22 December 1999 on the early warning and response
system for the prevention and control of communicable diseases under
Decision No 2119/98/EC of the European Parliament and of the Council
(notified under document number C(1999) 4016) (2000/57/EC). Official Journal
of the European Communities 2000; L21/32. 26 January 2000.
(http://europa.eu.int/eur-lex/pri/en/oj/dat/2000/l_021/l_02120000126en003200
35.pdf)
3. Meijer A, Valette M, Manuguerra J-C, P閞ez-Bre馻 P, Paget J, Brown C, van
der Velden K, on behalf of the Virology Working Group of the European
Influenza Surveillance Scheme. Implementation of the Community Network of
Reference Laboratories for Human Influenza in Europe. Journal of Clinical
Virology 2005. (http://dx.doi.org/10.1016/j.jcv.2005.02.005) .

HK destroys H2N2 live virus samples

Hong Kong´s Queen Mary Hospital has destroyed the influenza A (H2N2) live virus samples a United States-based institution sent for use in a quality-control proficiency panel, Hong Kong´s Center for Health Protection said on Wednesday.

    The World Health Organization (WHO) informed the center Tuesday that urgent action had to be taken to destroy the samples which were sent by the College of American Pathologists to laboratories in 18 countries for use in a quality-control proficiency panel.

    WHO acknowledged that the H2N2 virus, which circulated in people in 1957-58 until it eventually vanished in 1968, can readily transmit between people and a considerable segment of the population does not have immunity against it.

    Upon receiving the notification, the center immediately contacted the laboratory of Queen Mary Hospital, the sole local institution to receive the specimens in January and February.

    The hospital has confirmed the specimens in question had been kept safely and had not been operated upon by laboratory workers since April 1. Proper biosafety measures were observed all along. The laboratory destroyed the specimens on Tuesday.

    The Center for Health Protection said that no laboratory workers have influenza, nor are H2N2 isolates found in Hong Kong.