- Northern Hemisphere: Widespread Influenza Activity Persists
- WHO Update 5 (Week 50; 7 to 13 Dec 2003)
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- Summary
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- Influenza activity associated with influenza A(H3N2)
viruses continues to increase in Africa (Tunisia), Europe (Czech Republic,
Denmark, Finland, Italy, Norway, Russia, Switzerland, Russia Federation
and Ukraine) and North America (the United States), and persists in France
and some parts of Canada. In other European countries (Portugal, Spain
and the United Kingdom) and most parts of Canada, activity has declined.
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- Most influenza infections this season have been attributed
to influenza A(H3N2) viruses. The majority of viruses antigenically characterized
so far have been shown to be A/Fujian/411/2002-like; the rest have been
A/Panama/2007/99-like. There have been few reports of influenza A/Fujian/411/2002-like
virus detections from Asia. Influenza A(H1) and B viruses have also been
detected in some countries. Both B/Hong Kong/330/2001-like and B/Sichuan/379/99-like
viruses have been identified. The hemagglutinins of all influenza A(H1)
viruses characterized so far have been A/New Caledonia/20/99-like.
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- An avian influenza A(H5N1) outbreak in poultry in a chicken
farm in the Republic of Korea was reported on Tue 16 Dec 2003. The outbreak
was recognized by the death of about 19 000 chickens. Surviving chickens
in the affected farm were slaughtered. As of Mon 22 Dec 2003, 9 poultry
farms in 4 provinces were found to be infected by avian influenza. About
one million chickens and ducks are to be culled. The A(H5N1) strain isolated
is being examined to determine its relation to other influenza A(H5N1)
viruses, which emerged in Asia recently. So far no human A(H5N1) cases
have been reported.
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- Additional investigation of a recent influenza A(H9N2)
case in Hong Kong SAR China (<http://www.who.int/csr/don/2003_12_10/en/>)
is on going to determine the source of infection. Virus isolates have been
sent to the WHO Collaborating Centers for Reference and Research on Influenza
(<http://www.who.int/csr/disease/influenza/collabcentres/en/>) for
sequencing and antigenic makeup characterising to update the diagnostic
reagents available for National Influenza Centers (<http://www.who.int/csr/disease/influenza/influenzanetwork/en/>).
So far all further results of investigation appear to confirm the initial
findings that this is an isolated case.
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- For previous update <http://www.who.int/csr/don/2003_12_17a/en/>
For more information:WHO Influenza web site <http://www.who.int/csr/disease/influenza/influenzanetwork/en/>
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- Canada ------ During week 50, widespread activity of
influenza was reported in British Columbia and Ontario, while localised
or sporadic activity was reported in most of other parts of Canada. The
influenza-like illness (ILI) consultation rate was 52 cases per 1000 consultations,
which is below the baseline. During this week, 17 percent of 3983 laboratory
tests were positive for influenza A and no influenza B virus was detected.
Of the 294 influenza viruses antigenically characterized by the National
Microbiology Laboratory to date, 267 (91 percent) were A/Fujian/411/2002-like,
25 (8.5 percent) were A/Panama/2007/99-like, one was an A/New Caledonia/20/99
(H1N1)-like virus, and one was A(H1N2).
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- Czech Republic -------------- An increase of influenza
A(H3N2) activity was first noted in week 48. In week 50, localised activity
of influenza was reported with 8 influenza A viruses detected.
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- Denmark ------- Influenza activity continued to increase
in week 50 and was reported as localised with 7 influenza A viruses detected.
The ILI consultation rate was above the baseline level, but below the epidemic
threshold for this time of the year. All viruses isolated so far have been
confirmed to be A/Fujian/411/2002-like.
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- France ----- Widespread activity of influenza A(H3N2)
persisted in all regions in France except Languedoc-Roussillon.
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- Italy ----- Sporadic cases of A(H3N2) were identified
in week 50 with a slight increasing trend of increase in influenza activity.
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- Norway ------ Widespread influenza activity was reported
as widespread in week 50 for the 4th consecutive week. Overall incidence
of ILI continued to increase with a large proportion in the 0-to-4 year
age group. While influenza A(H3) activity was reported throughout the country,
A(H1) activity was confined to southeast Norway. All influenza A(H3) viruses
antigenically characterized so far were A/Fujian/411/2002-like.
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- Portugal -------- A decrease in influenza activity, first
observed in week 48, continued in week 50, although activity remained widespread.
Of the influenza viruses characterized so far this season, the majority
were A/Fujian/411/2002-like.
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- Russian Federation ------------------ Regional influenza
activity associated mainly with influenza A(H3N2) was observed to be increasing
in week 50 with 25 influenza A(H3N2) viruses isolated. Sporadic cases of
influenza A(H1N1) and B were also detected. Weekly morbidity was 0.69-1.5
percent for the whole population.
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- Spain ----- Influenza activity continued to decline in
week 50 with an ILI consultation rate of 117 cases per 100 000 population.
Localised activity of influenza was reported in the Castilla y Leon autonomic
community with 2 influenza A(H3) and 3 A non-subtyped viruses detected.
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- Switzerland ----------- In week 50 activity of influenza
A(H3N2) continued to increase and was reported as widespread with 8 influenza
A viruses detected. All influenza A(H3) viruses antigenically characterized
so far are A/Fujian/411/2002-like.
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- Ukraine ------- Localised influenza activity continued
to increase in week 50. The overall weekly ILI incidence increased by 9
percent compared with week 49, while the incidence in children increased
by 23 -35 percent in some cities.
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- United Kingdom -------------- In week 50, influenza activity
declined in all countries in the UK. The ILI consultation rate was within
the baseline activity range in England and Wales, while in Scotland, it
was at the normal seasonal level. During week 50, 57 influenza A(H3) viruses
were detected. Of the viruses antigenically characterized, 55 have been
confirmed as A/Fujian/411/2002-like, 3 as A/Panama/2007/99-like and 2 as
B/Hong Kong/330/2001-like.
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- United States ------------- Influenza activity continued
to increase during week 50. The overall ILI consultation rate was 7.4 percent,
which is above the national baseline of 2.5 percent. Widespread influenza
activity was reported in 36 states, and regional activity was reported
in 12 states and New York City during week 50; 35.8 percent of the specimens
tested were positive for influenza with 1342 influenza A viruses and 23
B viruses identified. Since week 40, the Centers for Disease Control and
Prevention in Atlanta have antigenically characterized 2 influenza A(H1)
viruses, 265 A(H3N2) viruses and 2 B viruses from the U.S.. Of the 265
A(H3N2) viruses characterized, 62 (23 percent) are A/Panama/2007/99-like
and 203 (77 percent) are A/Fujian/411/2002-like. The 2 A(H1) viruses are
antigenically similar to A/New Caledonia/20/99-like virus, and the 2 B
viruses are similar to B/Sichuan/379/99-like virus.
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- Other reports ------------- Low influenza activity was
reported in Austria, Chile, Hong Kong SAR China, Hungary, Iceland, India,
Japan, Latvia, Thailand and Tunisia.
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- Croatia, Madagascar and Poland reported no influenza
activity.
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- -- Marianne Hopp mjhopp12@yahoo.com
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- [Regularly updated maps of the influenza situation in
Europe can be viewed at the European Influenza Surveillance Scheme (EUSS)
website: <http://www.eiss.org/index.cgi>. - Mod.CP]
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- Patricia A. Doyle, PhD Please visit my "Emerging
Diseases" message board at: http://www.clickitnews.com/ubbthreads/postlist.php?Cat=&Board=emergingdiseases
Zhan le Devlesa tai sastimasa Go with God and in Good Health
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