W J Paget

Heterogeneous case definitions used for the surveillance of influenza in Europe.

We reviewed the case definitions used by 21 influenza sentinel-based surveillance networks in Western Europe. Two clinical syndromes were used with a wide range of case definitions that nevertheless shared common criteria. Although there is currently no international consensus, efforts are being undertaken to standardise influenza case definitions in Europe.

The evolution of influenza surveillance in Europe and prospects for the next 10 years

This report traces the evolution of surveillance programmes for influenza in the United Kingdom and countries of western Europe since the World Health Organisation (WHO) resolution to establish an international influenza reference centre in 1947. The introduction of clinical surveillance schemes in the late 1960s and their gradual integration with laboratory-based surveillance is described, with particular emphasis on the need for integrated surveillance based on population-specific denominators. The function of the European Influenza Surveillance Scheme (EISS), its work programme in the last 5 years, and the likely direction of future developments is outlined. The report advocates the EISS model of influenza surveillance, which involves the integrated collection of clinical and laboratory data in the same population using sentinel practitioners.

Harmonising the virological surveillance of influenza in Europe: results of an 18-country survey.

Abstract The European influenza surveillance scheme (EISS) is based on a surveillance model that combines clinical and virological data in the general population. Eighteen countries in Europe report weekly influenza activity to EISS (http://www.eiss.org). A questionnaire on the virological data collection was sent electronically to the EISS members. Questions on the specimen collection, representativity, laboratory diagnosis of influenza, reporting of variants, testing for other respiratory infections, serological testing, near-patient tests and preparedness for a pandemic were included. The results of the survey showed that for the typing of influenza, the methods polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HAI) methods are used most frequently. For the subtyping of influenza, HAI and PCR are used most often. An east-west divide was seen for the use of PCR in typing and subtyping (more PCR use in the west). Differences in the virological surveillance systems in Europe can make direct comparisons difficult because detection rates may differ by test. For the reporting of other respiratory infections besides influenza, many networks (68%) collect information on RSV. This is important because RSV causes similar clinical symptoms as influenza and can have a similar impact in terms of burden of disease. With the collection of RSV data, EISS is moving to a broader spectrum of viral respiratory diseases. The findings of this survey will be used to better harmonise laboratory methods in EISS in order to obtain more reliable and comparable information on influenza activity in Europe.

Avaliação epidemiológica e virológica da actividade gripal na Europa durante a temporada 2003-2004

Na Europa, a temporada da gripe 2003-2004 foi marcada pela disseminacao de uma nova variante, o virus A/Fujian/411/2002 (H3N2), um pouco differente do componente da estirpe A(H3N2) utilizada na vacina antigripal. Na Europa, foram detectados casos esporadicos no fim da temporada 2003-2004 e a actividade gripal associada com este virus occorreu no principio da temporada 2003-2004. Geralmente, a actividade gripal manifestou-se primeiro na Europa occidental (Irlanda, Reino Unido e peninsula iberica) nos meses de outobro e novembro, pois foi se deslocando em direcao do leste a traves da Europa, afectando a Letonia, a Lituania e a Polonia em janeiro e fevereiro de 2004. Em geral, a intensidade da actividade clinica foi superior a aquela da temporada 2002-2003 (segundo 13 redes das 20). Alem disso, nos paises que declarem dados por grupos etarios as taxas de consultas mais altas foram observadas em criancas de 0 a 14 anos. No entanto, apesar da emergencia desta nova variante A(H3N2), as incidencias clinicas nao aumentaram especialmente, comparadas com os dados historicos. A composicao da vacina antigripal 2004-2005 foi modificada comparada com a temporada 2003-2004, e inclui uma estirpe semelhante ao virus A/Fujian/411/2002 (H3N2) e uma nova estirpe de tipo B (B/Shanghai/361/2002).

Evaluación epidemiológica y virológica de la actividad gripal en Europa durante la temporada 2003-2004

En Europa, la temporada gripal 2003-2004 estuvo marcada por la diseminacion de una nueva variante, el virus A/Fujian/411/2002 (H3N2), un poco diferente del componente de la cepa A(H3N2) utilizada en la vacuna antigripal. En Europa se detectaron casos esporadicos a finales de la temporada 2002-2003 y la actividad gripal asociada con este virus ocurrio a comienzos de la temporada 2003-2004. Generalmente, la actividad gripal se manifesto primero en Europa occidental (Irlanda, Reino Unido y peninsula iberica) en los meses de octubre y noviembre, luego se desplazo gradualmente rumbo al este a traves de Europa, afectando a Letonia, Lituania y Polonia en enero y febrero de 2004. En general, la intensidad de la actividad clinica fue superior a la de la temporada 2002-2003 (segun 13 redes de las 20). Ademas, en los paises que declaran datos por grupos de edad, las tasas de consultas mas altas se observaron en ninos de 0 a 14 anos. Sin embargo, pese a la emergencia de esta nueva variante A(H3N2), las incidencias clinicas no aumentaron especialmente, comparadas con los datos historicos. La composicion de la vacuna antigripal 2004-2005 fue modificada comparada con la de la temporada 2003-2004, e incluye una cepa semejante al virus A/Fujian/411/2002 (H3N2) y una nueva cepa de tipo B (B/Shanghai/361/2002).