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WHO Update:

Northern Hemisphere: Influenza Epidemic Spreads to More Countries - WHO
Update 3

Significant increases in influenza activity associated with influenza
A(H3N2) viruses continue in some countries in Europe (Finland, France, and
Norway) and North America (United States); in other European countries
(Portugal and Spain), widespread influenza A(H3N2) activity persists. In
some parts of Canada and United Kingdom (UK), where influenza activity was
first noted this season, the number of cases has started to decline,
although it is too early to predict the trend.

A rising trend has also been observed in a number of European countries
(Czech Republic, Denmark, Italy, Latvia, Russian Federation, and
Switzerland), although influenza activity remains low at present.

Influenza B viruses are most frequently reported from Asia (Hong Kong
Special Administrative Region of China, Republic of Korea, and Thailand);
sporadic cases have been detected in Europe and North America. With the
exception of an outbreak in Iceland between weeks 41 and 46, very few
influenza A(H1) cases have been reported worldwide.

This season, most influenza outbreaks are being attributed to influenza
A(H3N2) virus, and most viruses antigenically characterized so far have
been confirmed to be A/Fujian/411/2002-like, with the rest being
A/Panama/2007/99-like.

Austria (29 Nov 2003)

Influenza A virus was first detected in week 48.

Canada (29 Nov 2003)

During week 48, influenza activity declined in Alberta and Saskatchewan but
increased in other parts of Canada, particularly British Columbia, Ontario,
and Nunavut. Influenza-like illness (ILI) consultation rate was 42 cases
per 1000 consultations, which is above the national baseline level for week
48. During the same week, 18 percent of 2567 laboratory tests were positive
for influenza A and no influenza B virus was detected. Of the 155 influenza
viruses antigenically characterized by the National Microbiology Laboratory
to date, 128 (83 percent) are A/Fujian/411/2002-like, 25 (16 percent) are
A/Panama/2007/99-like and one is an A/New Caledonia/20/99-like virus.

Denmark (29 Nov 2003)

ILI activity started to increase in week 47. In week 48, the ILI
consultation rate was above the national baseline, with one influenza
A/Fujian/411/2002-like virus detected.

Finland (6 Dec 2003)

Increased influenza activity has been observed since week 47. During week
49, influenza activity was widespread, with 30 influenza A viruses detected.

France (29 Nov 2003)

Increased influenza activity has been observed. In week 48, regional
activity of influenza A/Fujian/411/2002-like viruses was reported in 13
regions.

Morocco (22 Nov 2003)

So far this season, influenza activity has remained low, with one influenza
A(H1N1) and one A(H3N2) virus detected.

Norway (29 Nov 2003)

Influenza activity continued to increase. In week 48, widespread activity
of influenza A(H3N2) was reported throughout the country. All of the 21
A(H3N2) viruses antigenically characterized so far are A/Fujian/411/2002-like.

Portugal (29 Nov 2003)

In week 48, influenza A(H3N2) activity was reported as widespread for the
3rd consecutive week. All influenza viruses antigenically characterized so
far this season are A/Fujian/411/2002-like.

Republic of Korea (29 Nov 2003)

The first influenza viruses for the season two influenza B viruses were
detected in week 48.

Russian Federation (29 Nov 2002)

The ILI incidence rate continued to rise in week 48 and exceeded the
epidemic threshold in Moscow and St Petersburg. All 3 influenza virus
subtypes A(H1N1), A(H3N2) and B were detected. During the same week, 5
influenza A(H3N2) viruses were antigenically characterized and confirmed as
A/Panama/2007/99-like.

Spain (29 Nov 2003)

Influenza activity continued to be widespread during week 48. However, ILI
incidence rate slowed down in the Castilla y Leon autonomic community.

Switzerland (29 Nov 2003)

Increased influenza activity was observed in week 48, particularly in the
western part of the country where 9 influenza A viruses were detected.

United Kingdom (29 Nov 2003)

Influenza activity appears to have levelled off but the trend remains
unclear. In week 48, ILI consultation rate remained almost the same as in
week 47 in England, continued to decrease in Northern Ireland and Scotland,
and kept rising in Wales (although it remained below the baseline level).
During week 48, 44 influenza A(H3) viruses and one B virus were detected.
Of the viruses antigenically characterized so far, 35 have been confirmed
as A/Fujian/411/2002-like and 3 as A/Panama/2007/99-like.

United States (29 Nov 2003)

Influenza activity continued to increase during week 48. Overall ILI
consultation rate was 5.1 percent, which is above the national baseline of
2.5 percent. Widespread influenza activity was reported in 13 states and
regional activity was reported in 16 states during week 48; 39.1 percent of
the specimens tested were positive for influenza with 1302 influenza A
viruses and 7 B viruses identified. Since week 40, the Centers for Disease
Control and Prevention in Atlanta have antigenically characterized 157
influenza A(H3N2) viruses, of which 45 (29 percent) are
A/Panama/2007/99-like and 112 (71 percent) are A/Fujian/411/2002-like.

Other reports

Low influenza activity was reported in Czech Republic, Germany, Hong Kong
SAR, Italy, Thailand, and Ukraine. No influenza activity was reported in
Croatia, Iceland, Japan, or Poland.