(Griep)pandemie H1N1 “Wat staat ons te wachten?” Voorlichtingsbijeenkomst Grieppandemie 20 augustus 2009 Douwe van der Werf Arts Team Infectieziektebestrijding GGD IJsselland 038 – 428 1 656 infectieziekten@ggdijsselland.,nl

Influenzapandemie H1N1: wat staat ons te wachten? Van jaarlijkse griepgolf naar pandemie Waarom speciale voorbereidingen? Actuele inschatting: het gaat meevallen Maar: blijf waakzaam!

Influenza

Transmissie

Transmissie

Replicatie virus

Normale beloop influenza 40 39 o C 38 37 1 2 3 4 5 6 7 8 Dagen na eerste klachten Verstopte neus Zere keel Spierpijn Hoofdpijn Hoesten Malaise Besmettelijkheid

Influenza: complicaties Lage luchtwegen(direct effect virus) - Croup, bronchiolitis (kinderen) - Primaire virale pneumonie Secondaire bacteriële infectie - Pneumonie - Otitis media Complicaties andere organen, bv. - Hartfalen, myocarditis - Ontregelde suikerziekte

Risicogroepen Ouderen, m.n. ook in verpleeg/verzorgingshuizen Zuigelingen Patiënten met: - COPD - asthma - cystic fibrosis etc. - hart- en vaatziekten - immunosuppressie door ziekte/behandeling - haematologische ziekten zoals leukemie - nierziekten diabetes mellitus NB: bij pandemie mogelijk andere risicogroepen, b.v. zwangeren, jongvolwassenen, obesitas

Van jaarlijkse griepgolf naar pandemie

Seizoensgriep in NL Via huisarts +/- 4 miljoen griepprikken in maanden september/oktober aan risicogroepen (opkomst 80%) Over gehele griepseizoen krijgt plm. 1% van de bevolking ziekteverschijnselen Schatting: jaarlijks nog steeds 1000 extra sterfgevallen door complicaties bij griep

Clinical attack rate seizoensgriep : 1: 100 Bron CMR-Peilstations Nederland 1970-05 1985-2005 IAZ 2 – 6/ 1.000/week 19

Pandemics of influenza Recorded human pandemic influenza (early sub-types inferred) H2N2 H2N2 H1N1 H1N1 Pandemic H1N1 H3N8 H3N2 1915 1925 1955 1965 1975 1985 1995 2005 1895 1905 2010 2015 What are pandemics? Pandemics are when a new influenza A emerges to which most or many of the population have no immunity. The result usually from an animal influenza combining some of its genes with a human influenza. To be a pandemic strain an influenza A virus needs to have three or four characteristics. They need to be able to infect humans, to cause disease in humans and to spread from human to human quite easily. An additional criteria that is often applied is that many or most of the population should be non-immune to the new virus. Note this animated slide was first developed by the National Institute of Infectious Disease in Japan and we are grateful to them and especially Masato Tashiro for letting us use it. 1889 Russian influenza H2N2 1900 Old Hong Kong influenza H3N8 1918 Spanish influenza H1N1 1957 Asian influenza H2N2 1968 Hong Kong influenza H3N2 2009 Pandemic influenza H1N1 H7 H5 H9* 1980 1997 Recorded new avian influenzas 1996 2002 1999 2003 1955 1965 1975 1985 1995 2005 Reproduced and adapted (2009) with permission of Dr Masato Tashiro, Director, Center for Influenza Virus Research, National Institute of Infectious Diseases (NIID), Japan. Animated slide: Press space bar

Verschil jaarlijkse griepgolf – pandemie Griepgolf jaarlijks Reeds bekend virus 1% zieken Vaccin beschikbaar Bekend beloop Leeftijdsverdeling zieken bekend Pandemie Nieuw influenzavirus 25% of meer zieken Vaccin (nog) niet beschikbaar Ziektebeloop kan veel ernstiger zijn Kan toeslaan in speciale leeftijdsgroepen

Waarom speciale voorbereidingen?

Clinical attack rate van de seizoensgriep NL: 1%

Seasonal influenza compared to pandemic — proportions of types of cases Deaths Requiring hospitalisation Clinical symptoms But remember this is idealised – and in 2009 in North America this is not putting as many people into Hospital as you would expect from the above. In the 2009 pandemic it is not clear yet what percentage are asymptomatic. Two reasonable estimates are 33% and 50% of the total infected. [Note to Uwe – can you increase the asymptomatic fraction in both to make them look about 33% of the total] Deaths Requiring hospitalisation Asymptomatic Clinical symptoms Asymptomatic Seasonal influenza Pandemic

Proportion of total cases, consultations, hospitalisations or de Idealised national curve for planning, Europe 2009: Reality is never so smooth and simple Initiation Acceleration Peak Declining 25% aths 20% 15% For planning purposes there are these four components of a pandemic wave – Initiation, Acceleration, Peak and Decline. The percentage on the vertical axis represents the proportion of all those infected in the first wave that are infected in the different phases After the decline there may be a second and even a third wave before influenza settles back down to its seasonal pattern again. The seasonal flu is usually worse than the years before the pandemic because the seasonal flu is invigorated with new genetic material. The same four phases actually apply to epidemics as well. This particular wave has been given an erratic Initiation Phase representing what is happening in Europe in the summer and perhaps early Autumn when there are small outbreaks and it is not clear when each country will enter their Acceleration Phase. However, no pandemic has ever behaved in quite so neat a way as shown here. Pandemics don’t follow set patterns and each is different. It is also important that this is a national curve. The local curves are more narrow and with a higher central peak, i.e. local pandemic spread is shorter and sharper but also highly variable. Proportion of total cases, consultations, hospitalisations or de 10% 5% 0% 1 2 3 4 5 6 7 8 9 10 11 12 Week Single-wave profile showing proportion of new clinical cases, consultations, hospitalisations or deaths by week. Based on London, second wave 1918. Source: Department of Health, UK Animated slide: Please wait

One possible European scenario — summer 2009 Initiation Acceleration Peak Declining 25% 20% 15% Proportion of total cases, consultations, hospitalisations or deaths Presently (May-June 2009) Europe seems to be in a prolonged initiation phase with occasional outbreaks and small peaks. This could go on for months with the real first wave coming in the autumn or winter. The pandemic waves will occur at different dates in different countries. And even within one country it will not affect every area at once 10% 5% 0% Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr Month In reality, the initiation phase can be prolonged, especially in the summer months. What cannot be determined is when acceleration takes place. Animated slide: Press key

Draaiboeken influenzapandemie Start en ontwikkeling grieppandemie Voorkomen/vertragen van de pandemie Behouden van minimale zorg in de eerste lijn Behouden van minimale zorg in de tweede lijn Maatregelen Voorkomen van maatschappelijke ontwrichting en handhaven essentiële diensten Tamiflu behandeling & profylaxe Vaccinatie Tijd

Aims of community reduction of influenza transmission — mitigation Delay and flatten epidemic peak. Reduce peak burden on healthcare system and threat. Somewhat reduce total number of cases. Buy a little time. No intervention This slide the original of which was developed by the United States CDC illustrates the theoretical aims of community mitigation by public health measures, mass use of antivirals etc. However it needs to be appreciated that the effectiveness of PHM is by no means certain. A further discussion of this can be found through the ECDC PHM ‘Menu’ http://ecdc.europa.eu/en/Health_Topics/Pandemic_Influenza/phm.aspx Daily cases With interventions Days since first case Based on an original graph developed by the US CDC, Atlanta Animated slide: Press key

Zorgverleners Continuïteit van zorg garanderen Via maatregelen continuïteitsplan

Zorg aan patiënt/cliënt uit risicogroep: Zorgverleners Zorg aan patiënt/cliënt uit risicogroep: Voorkomen van besmetting via eigen personeel (hygiëne plus griepvaccinatie personeel in direct contact!) Tijdige (binnen 48 uur) behandeling Tamiflu® (aangepaste richtlijn NVVA – afspraken met huisartsen) - Vaccineren op moment dat vaccin beschikbaar komt

het lijkt allemaal mee te vallen “Nieuw H1N1 virus” Actuele inschatting: het lijkt allemaal mee te vallen

Revised European planning assumptions for the pandemic – first wave, pandemic (H1N1) 2009 12% of workforce Peak absence rate 0.1% to 0.2% (cannot exclude up to 0.35%) of clinical cases Case fatality rate 2% of clinical cases Hospitalisation rate 15% of clinical cases Complication rate 6.5% (local planning assumptions 4.5% to 8%) per week Peak clinical attack rate 30% Clinical attack rate These assumptions represent a reasonable worst case applying to one European country (the United Kingdom) with data available as of July 2009. They should not be used for predictions. Courtesy of Department of Health, UK, http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_102892

Maar: blijf waakzaam

Idealised curves for local planning 25% aths 20% 15% Proportion of total cases, consultations, hospitalisations or de Also there is a lot of local variation. This is an idealised smooth national curve with idealised local curves showing how the national curve can hides a series of short, sharp local epidemics. These can have higher peaks and this is why planning guidance for local areas often has higher planning assumptions (e.g. numbers of patients a hospital can expect to have to deal with) that is higher than what you might expect from national idealised curves. 10% 5% 0% 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Week In reality, larger countries can experience a series of shorter but steeper local epidemics. Animated slide: Press space bar

“Spanish Flu” A(H1N1): 1918 -1919 Approximately 20 million people died worldwide, and 600,000 in US

Blijf waakzaam Piek van Nieuwe Influenza A (H1N1) kan samenvallen met piek seizoensgriep.

Wie / wat is de GHOR?

‘Warm’ ‘Koud’ Definitie GHOR Organisatie voor: Coördinatie, aansturing en Regie geneeskundige hulpverlening Advisering gemeenten en andere overheden Geneeskundige hulpverlening bij ongevallen en rampen ‘Koud’

GHOR processen Geneeskundige hulpverlening somatisch Redding en ambulancehulpverlening Behandeling (bijvoorbeeld in het ziekenhuis) Ontslag en eventuele revalidatie Psychosociale Hulpverlening bij Ongevallen en Rampen (PSHOR) Collectieve opvang van slachtoffers direct na een ramp Het verlenen van psychosociale hulp na een ramp Preventieve openbare gezondheidszorg (POG) Infectieziektebestrijding en technische hygiënezorg Medische milieukunde

Coördinatie en aansturing GHOR Dit is de lijn, daarnaast alle lijntjes naar ziekenhuizen, 1e en andere ambu’s, psycho hulpverlening, etc etc Registratie

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