A widespread community cluster of H275Y oseltamivir-resistant A(H1N1)pdm09 influenza in Australia

Transcription

1 A widespread community cluster of H275Y oseltamivir-resistant A(H1N1)pdm09 influenza in Australia Aeron Hurt WHO Collaborating Centre for Reference and Research on Influenza, Melbourne

2 Overview - Background - Are we seeing a changing resistance pattern? - Community cluster of cases in Australia - Why current oseltamivir-resistant viruses virus may be fitter - Summary

3 We all remember the spread of H275Y seasonal A(H1N1) variant in Percentage of Oseltamivir-resistant viruses Vast majority of cases were not treated with oseltamivir Europe Meijer et. al., EID, 15 (4), 2009

4 Percentage of Oseltamivir-resistant viruses We all remember the spread of H275Y seasonal A(H1N1) variant in Vast majority of cases were not treated with oseltamivir Europe = prevalence of oseltamivirresistant H275Y mutants in Oceania, South East Asia and South Africa Oceania, South East Asia, South Africa Meijer et. al., EID, 15 (4), 2009

5 Percentage Percentage of of Oseltamivir-resistant Oseltamivir-resistant viruses viruses We all remember the spread of H275Y seasonal A(H1N1) variant in = prevalence of oseltamivirresistant H275Y mutants in Oceania, South East Asia and South Africa Oceania, South East Asia, South Africa Vast majority of cases were not treated with oseltamivir Highly transmissible ( fit ) oseltamivir-resistant H275Y H1N1 viruses can occur Dismissing previous theory that oseltamivirresistant Europe strains are always unfit Oseltamivir-resistant strains can circulate and spread in the absence of drug usage Important lessons when considering resistance in A(H1N1)pdm09 Globally from 0 to 100% in one year! Meijer et. al., EID, 15 (4), 2009

6 Global A(H1N1)pdm09 resistance testing conducted within GISRS in the first two years of the pandemic: 447 oseltamivir-resistant viruses detected out of >27000 A(H1N1)pdm09 viruses tested = 1.7% frequency of resistance Such a low frequency of resistance was encouraging similar data was seen at a country or regional level

7 # (%) of oseltamivir-resistant A(H1N1)pdm09 viruses detected Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 37/6740 (0.5%) 45/5587 (0.8%) 35/3652 (1.0%) 27/2864 (0.9%) Asia-Pacific (Leang et. al., 2012, In preparation) 12/1123 (1.1%) 11/1873 (0.6%)

8 # (%) of oseltamivir-resistant A(H1N1)pdm09 viruses detected Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 37/6740 (0.5%) 45/5587 (0.8%) 35/3652 (1.0%) 27/2864 (0.9%) Asia-Pacific (Leang et. al., 2012, In preparation) 12/1123 (1.1%) 11/1873 (0.6%)

9 # (%) of oseltamivir-resistant A(H1N1)pdm09 viruses detected Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 37/6740 (0.5%) 45/5587 (0.8%) 35/3652 (1.0%) 27/2864 (0.9%) Asia-Pacific (Leang et. al., 2012, In preparation) 12/1123 (1.1%) 11/1873 (0.6%) 1.5% A(H1N1)pdm09 resistance in Thailand Dr Yingyong (Day 1 presentation) But as discussed in group work yesterday it is important to know about patient details.. were they treated with oseltamivir? Hospitalised? Immunocompromised?

10 Best insight into whether spread of resistant viruses is occurring is if there is increased detection of oseltamivir-resistant viruses in untreated patients From the first two years of the A(H1N1)pdm09 pandemic, only 14% of oseltamivir-resistant cases reported to WHO HQ were from patients with no exposure to antiviral drugs Majority of oseltamivir-resistant viruses from patients under treatment

11 # (%) of oseltamivir-resistant cases with no history of oseltamivir exposure before specimen collection Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 4/35 (11.4%) 5/44 (11.4%) 25/34 (73.5%) 10/24 (41.7%) Asia-Pacific (Leang et. al., 2012, In preparation) 1/12 (8.3%) 5/11 (45.5%)

12 # (%) of oseltamivir-resistant cases with no history of oseltamivir exposure before specimen collection Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) 4/35 (11.4%) 25/34 (73.5%) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 5/44 (11.4%) 10/24 (41.7%) Big increase in % of resistant viruses from untreated patients!! Asia-Pacific (Leang et. al., 2012, In preparation) 1/12 (8.3%) 5/11 (45.5%)

13 # (%) of oseltamivir-resistant cases with no history of oseltamivir exposure before specimen collection Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 4/35 (11.4%) 5/44 (11.4%) 25/34 (73.5%) 10/24 (41.7%) Asia-Pacific (Leang et. al., 2012, In preparation) 1/12 (8.3%) 5/11 (45.5%)

14 # (%) of oseltamivir-resistant cases with no history of oseltamivir exposure before specimen collection Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 4/35 (11.4%) 5/44 (11.4%) 25/34 (73.5%) 10/24 (41.7%) Asia-Pacific (Leang et. al., 2012, In preparation) 1/12 (8.3%) 5/11 (45.5%) The data suggest that the frequency of transmission of oseltamivirresistant viruses appears to be increasing

15 # (%) of oseltamivir-resistant cases with no history of oseltamivir exposure before specimen collection Region 2009/ /2011 U.S.A (Storms et. al., 2012, EID, 18 (2)) United Kingdom (Lackenby et. al., 2011, Eurosurveillance, 16 (5)) 4/35 (11.4%) 5/44 (11.4%) 25/34 (73.5%) 10/24 (41.7%) Asia-Pacific (Leang et. al., 2012, In preparation) 1/12 (8.3%) 5/11 (45.5%) From a surveillance point-of-view collection of oseltamivir exposure (usage) data is important information to collect, along with patient setting and immune status

16 So what is our knowledge of transmission of oseltamivir-resistant A(H1N1)pdm09 viruses? Nosocomial transmission A few examples.. University Hospital of Wales, Cardiff - 4 cases of transmission of resistant virus to untreated immunocompromised patients on same ward - No spread to other wards or community Moore et. al., Evidence of person-to-person transmission of oseltamivir-resistant pandemic influenza A(H1N1) 2009 virus in a hematology unit. J Infect Dis Jan 1;203(1): Duke University Medical Centre, USA - 3 cases of oseltamivir resistance in untreated immunocompromised patients - Not sharing same room but on same ward Chen et. al., Cluster of oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infections on a hospital ward among immunocompromised patients--north Carolina, J Infect Dis Mar 15;203(6):838-46

17 So what is our knowledge of transmission of oseltamivir-resistant A(H1N1)pdm09 viruses? Nosocomial transmission A few examples.. University Hospital of Wales, Cardiff - 4 cases of transmission of resistant virus to untreated immunocompromised patients on same ward - No spread to other wards or community Moore et. al., Evidence of person-to-person transmission of oseltamivir-resistant pandemic influenza A(H1N1) 2009 virus in a hematology unit. J Infect Dis Jan 1;203(1): Duke University Medical Centre, USA - 3 cases of oseltamivir resistance in untreated immunocompromised patients - Not sharing same room but on same ward Chen et. al., Cluster of oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infections on a hospital ward among immunocompromised patients--north Carolina, J Infect Dis Mar 15;203(6):838-46

18 So what is our knowledge of transmission of oseltamivir-resistant A(H1N1)pdm09 viruses? Nosocomial transmission A few examples.. University Hospital of Wales, Cardiff - 4 cases of transmission of resistant virus to untreated immunocompromised patients on same ward - No spread to other wards or community Moore et. al., Evidence of person-to-person transmission of oseltamivir-resistant pandemic influenza A(H1N1) 2009 virus in a hematology unit. J Infect Dis Jan 1;203(1): Duke University Medical Centre, USA - 3 cases of oseltamivir resistance in untreated immunocompromised patients - Not sharing same room but on same ward Chen et. al., Cluster of oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infections on a hospital ward among immunocompromised patients--north Carolina, J Infect Dis Mar 15;203(6):838-46

19 But what about transmission in the community between otherwise healthy people? North Carolina school camp Transmission between cabin-mates undergoing chemoprophylaxis at a school camp Oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infection in two summer campers receiving prophylaxis--north Carolina, MMWR Morb Mortal Wkly Rep Sep 11;58(35): Cluster of cases on a Vietnamese train ride 42-hour train journey, 10 students sat together Following train ride, 6 developed ILI confirmed as pdm H1 with H275Y mutation, none undergoing oseltamivir treatment No evidence of further transmission A community cluster of oseltamivir-resistant cases of 2009 H1N1 influenza. Le QM, Wertheim HF, Tran ND, van Doorn HR, Nguyen TH, Horby P; Vietnam H1N1 Investigation Team. N Engl J Med Jan 7;362(1):86-7.

20 But what about transmission in the community between otherwise healthy people? North Carolina school camp Transmission between cabin-mates undergoing chemoprophylaxis at a school camp Oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infection in two summer campers receiving prophylaxis--north Carolina, MMWR Morb Mortal Wkly Rep Sep 11;58(35): Cluster of cases on a Vietnamese train ride 42-hour train journey, 10 students sat together Following train ride, 6 developed ILI confirmed as pdm H1 with H275Y mutation, none undergoing oseltamivir treatment No evidence of further transmission A community cluster of oseltamivir-resistant cases of 2009 H1N1 influenza. Le QM, Wertheim HF, Tran ND, van Doorn HR, Nguyen TH, Horby P; Vietnam H1N1 Investigation Team. N Engl J Med Jan 7;362(1):86-7.

21 But what about transmission in the community between otherwise healthy people? North Carolina school camp Transmission between cabin-mates undergoing chemoprophylaxis at a school camp Oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infection in two summer campers receiving prophylaxis--north Carolina, MMWR Morb Mortal Wkly Rep Sep 11;58(35): Cluster of cases on a Vietnamese train ride 42-hour train journey, 10 students sat together Following train ride, 6 developed ILI confirmed as pdm H1 with H275Y mutation, none undergoing oseltamivir treatment No evidence of further transmission A community cluster of oseltamivir-resistant cases of 2009 H1N1 influenza. Le QM, Wertheim HF, Tran ND, van Doorn HR, Nguyen TH, Horby P; Vietnam H1N1 Investigation Team. N Engl J Med Jan 7;362(1):86-7.

22 Widespread cluster of cases of oseltamivir-resistant viruses in the community in Australia in 2011

23 Widespread cluster of cases of oseltamivir-resistant viruses in the community in Australia in 2011 South Australia Northern Territory Tasmania Queensland Western Australia NSW (Hunter New England health district) NSW (Sydney region) Victoria January February March April May June July August September October 2011 Hurt et al, 2012, J Infect Dis May 4. [Epub ahead of print]

24 Widespread cluster of cases of oseltamivir-resistant viruses in the community in Australia in 2011 Blue dots = sensitive strain Red dots = oseltamivir resistant H275Y strain Hospitalised and immunocompromised patients undergoing oseltamivir treated South Australia Northern Territory Tasmania Queensland Western Australia NSW (Hunter New England health district) NSW (Sydney region) Victoria January February March April May June July August September October 2011 Hurt et al, 2012, J Infect Dis May 4. [Epub ahead of print]

25 Widespread cluster of cases of oseltamivir-resistant viruses in the community in Australia in 2011 Blue dots = sensitive strain Red dots = oseltamivir resistant H275Y strain Concerning number of resistant cases from one location!!! South Australia Northern Territory Tasmania Queensland Western Australia NSW (Hunter New England health district) NSW (Sydney region) Victoria January February March April May June July August September October 2011 Hurt et al, 2012, J Infect Dis May 4. [Epub ahead of print]

26 Frequency of resistance in the Hunter New England Region N o. o f sp ecim en s co n firm ed as in flu en za p o sitive A(H1N1)pdm09 epidemic curve in Hunter New England Overall for season May/June July August September Frequency per month 5/52 (10%) 20/85 (24%) 4/45 (9%) 0/4 (0%) 29/186 (16%)

27 Frequency of resistance in the Hunter New England Region N o. o f sp ecim en s co n firm ed as in flu en za p o sitive A(H1N1)pdm09 epidemic curve in Hunter New England May/June July August September Regular and rapid shipping of viruses to WHO CC enabled the emergent resistant strain to be detected quickly and whilst the outbreak was still occurring

28 N o. o f sp ecim en s co n firm ed as in flu en za p o sitive Shipment of viruses from the lab: th June 1 st July 8 th July 15 th July 12 th August 19 th August 26 th August 30 th August 2 nd Sept 9 th Sept 16 th Sept 23 rd Sept A(H1N1)pdm09 epidemic curve in Hunter New England May/June July August September - Close monitoring of the situation, collection of detailed patient information - Discussions regarding the appropriateness of ongoing oseltamivir use

29 Summary of clinical details of oseltamivir resistant A(H1N1)2009 cases in Hunter New England region To investigate the clinical details of the 29 HNE oseltamivir resistant cases an ethics waiver was granted and authorized under the NSW Public Health Act 2010 as an urgent public health investigation. Hospital records were investigated and interviews with patients and GPs were conducted

30 Summary of clinical details of oseltamivir resistant A(H1N1)2009 cases in Hunter New England region Patient detail no. (%) a Male 12 (41%) Pregnant 3 (10%) Asthma 6 (21%) Smoker 6 (21%) Influenza vaccination in (10%) Treated with oseltamivir prior to specimen being taken 1 (3%) Cough 25 (86%) Fever 22 (76%) Hospital admission 7 (24%) ICU admission 0 (0%) Deaths 0 (0%) a number and % of cases is out of 29 oseltamivir-resistant cases detected in the Newcastle region

31 Geographic spread of oseltamivir resistant H275Y A(H1N1)2009 cases in Hunter New England region HNE health district Northern Territory Western Australia Queensland Perth South Australia New South Wales Victoria Newcastle Sydney Orange ,000 kilometers Tasmania HNE health district population of 840,00 people Newcastle major city (population ), sixth largest city in Australia Provides tertiary referral specialist services for northern NSW Located approximately 120 km north of the NSW capital, Sydney

32 Geographic spread of oseltamivir resistant H275Y A(H1N1)2009 cases in Hunter New England region Warialda (490 Km from Newcastle) Scone (150 Km from Newcastle) Bulahdelah (90 Km from Newcastle) Three additional cases outside of the Newcastle region Sydney Newcastle 26/29 oseltamivir resistant cases within 50 Km range of Newcastle

33 Geographic spread of oseltamivir resistant H275Y A(H1N1)2009 cases in Hunter New England region During the same period two oseltamivir resistant viruses were also detected elsewhere in NSW Orange (380 Km from Newcastle) Sydney Newcastle Western Australia 26/29 oseltamivir resistant cases within 50 Km range of Newcastle NSW (Hunter New England health district) NSW (Sydney region) June July August September

34 Geographic spread of oseltamivir resistant H275Y A(H1N1)2009 cases in Hunter New England region Western Australia Northern Territory South Australia Queensland HNE health district As well as one resistant strain from Perth in September 2011 New South Wales Newcastle Perth Victoria Sydney Orange ,000 kilometers Tasmania Western Australia NSW (Hunter New England health district) NSW (Sydney region) June July August September

35 All of the oseltamivir resistant cases were genetically similar HNE, other NSW and WA oseltamivir resistant H275Y viruses in red HNE oseltamivir sensitive viruses in blue Newcastle/37/2011 Newcastle/132/2011 Newcastle/53/2011 Newcastle/82/2011 Newcastle/84/2011 Newcastle/151/2011 Newcastle/62/2011 Sydney/74/2011 Sydney/59/2011 South Australia/24/2011 E129K Newcastle/2/2011 Newcastle/85/2011 Newcastle/17/2011 Hong Kong/3973/ Newcastle/89/2011 Perth/194/2011 Philippines/1343/2011 V537A South Australia/4/2011 Brisbane/70/ Newcastle/1/ Singapore/6/2011 American Samoa/4520/2011 Korea/664/2010 Japan/8153/2011 Brunei/15/2011 Wisconsin/16/2011 Singapore/9/2011 S160G Victoria/809/2011 Brisbane/210/ Newcastle/163/2011 Townsville/78/2011 Hawaii/01/2011 Maryland/06/2011 Macau/200808/2011 Brisbane/67/2011 Heilongjiang-Xiangfang/191/2011 Tanzania/42/2011 A214T Texas/04/ Washington/02/2011 Victoria/512/2011 Sydney/217/2010 Newcastle/58/2011 N16K Newcastle/14/ Newcastle/47/2011 S468N Indiana/05/2011 Maryland/07/2011 Pennsylvania/07/2011 D114N Christchurch/10/2011 Texas/10/2011 Brisbane/15/2011 Santiago/7774/2011 North Carolina/02/2011 Sydney/12/2011 E391K Alaska/09/2011 Tennessee/02/2011 D114N Perth/29/ New York/07/2011 Christchurch/16/2010 Oregon/02/2011 E391G Taiwan/967/2011 California/17/2011 Washington/09/ Brisbane/72/2011 New York/01/2011 California/07/2009 HA sequences NA sequences S44G Newcastle/82/2011 Newcastle/17/2011 Newcastle/2/2011 Newcastle/37/2011 Newcastle/53/2011 Newcastle/62/2011 Sydney/59/2011 Newcastle/89/2011 Newcastle/85/2011 Newcastle/132/2011 Newcastle/151/2011 V62I Sydney/74/2011 Perth/194/2011 N386S Newcastle/84/2011 South Australia/24/2011 Hong Kong/3973/2011 Philippines/1343/2011 Newcastle/1/2011 Brisbane/70/2011 Brisbane/67/2011 N44S Brunei/15/2011 Singapore/6/2011 South Australia/4/2011 Sydney/217/2010 Victoria/512/2011 Singapore/9/2011 Victoria/809/2011 S52N Newcastle/163/ Brisbane/210/2011 Townsville/78/ Macau/200808/2011 Newcastle/58/ Newcastle/14/2011 Newcastle/47/2011 Christchurch/10/2011 Sydney/12/2011 V241I Brisbane/15/2011 American Samoa/4520/2011 N369K Japan/8153/ Hawaii/01/2011 Washington/02/2011 Korea/664/2010 Wisconsin/16/2011 N44S Tanzania/42/2011 Texas/04/2011 Heilongjiang-Xiangfang/191/2011 Maryland/06/2011 Indiana/05/2011 Texas/10/2011 Maryland/07/2011 North Carolina/02/2011 Alaska/09/2011 Pennsylvania/07/2011 Santiago/7774/2011 New York/07/2011 Tennessee/02/2011 California/17/2011 Taiwan/967/ Washington/09/2011 Brisbane/72/2011 New York/01/2011 Oregon/02/2011 Christchurch/16/2010 Perth/29/2011 California/07/2009 The oseltamivir resistant viruses were genetically distinct, suggesting spread of the strain from a single source The resistant strains were NOT antigenically distinct, and were antigenically similar to the current A(H1N1)2009 vaccine strain A/California/7/2009.

36 So is there something special about these viruses that allowed them to spread? Early studies of seasonal A(H1N1) H275Y virus demonstrated that the resistance mutation decreased the ability of the virus to transmit and replicate But analysis of the strains that spread globally in 2008 showed that permissive NA mutations that were present in the virus before the H275Y may have meant the virus could still replicate and transmit with the H275Y mutation Holmes, E. Science. Vol 328

37 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? The V234M & R222Q mutations indentified in the Seasonal A(H1N1) are not in A(H1N1)pdm09 NAs

38 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? The V234M & R222Q mutations identified in the Seasonal A(H1N1) are not in A(H1N1)pdm09 NAs Plot of all mutations that have occurred in the NA of A(H1N1)pdm09 viruses over the last few years % Occurrence in circulating strains N369K N241I N44S N386S 10 0 March/April May June July August September October November December January February March April May June July August September October November December January February March April May June July August/Sep NA-H275Y NA-L415M NA-M15I NA-N189S NA-N248D NA-N369K NA-N386S NA-N397K NA-N44S NA-S247N NA-S82P NA-T332K NA-V106I NA-V241I NA-V394I Hurt et al, 2012, J Infect Dis May 4. [Epub ahead of print]

39 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? The V234M & R222Q mutations identified in the Seasonal A(H1N1) are not in A(H1N1)pdm09 NAs Plot of all mutations that have occurred in the NA of A(H1N1)pdm09 viruses over the last few years % Occurrence in circulating strains All four mutations were present in the HNE resistant strains - Three appear to stabilise the NA when analysed computationally N369K N241I N44S N386S 10 0 March/April May June July August September October November December January February March April May June July August September October November December January February March April May June July August/Sep NA-H275Y NA-L415M NA-M15I NA-N189S NA-N248D NA-N369K NA-N386S NA-N397K NA-N44S NA-S247N NA-S82P NA-T332K NA-V106I NA-V241I NA-V394I Hurt et al, 2012, J Infect Dis May 4. [Epub ahead of print]

40 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? Decreasing stability WT Increasing stability NA mutations

41 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? The H275Y mutation decreases stability of the NA Decreasing stability WT Increasing stability NA mutations

42 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? But when you add one of the permissive mutations it improves stability Decreasing stability WT Increasing stability NA mutations

43 So how about permissive mutations with the oseltamivir resistant viruses detected in Hunter New England region? Multiple permissive mutations improve stability even further Decreasing stability WT Increasing stability NA mutations Large improvement in stability of the H275Y variant when N369K + V241I + N386S are added to the NA

44 Decreasing stability WT Increasing stability NA mutations Suggests that viruses with N369K + V241I + N386S already in the NA (e.g. Newcastle strains) may be less compromised with the addition of the H275Y mutation than earlier A(H1N1)pdm 09 strains

45 Decreasing stability WT Increasing stability NA mutations Suggests that viruses with N369K + V241I + N386S already in the NA (e.g. Newcastle strains) may be less compromised with the addition of the H275Y mutation than earlier A(H1N1)pdm 09 strains N369K and V241I are in the majority of strains currently analysed at WHOCC Melb and in Republic of Korea Dr. Kang (Poster presentation) Q308H G77E Fiji/3/12 jan Fiji/2/12 jan Christchurch/60/11 sep Brisbane/210/11LR jun Newcastle/163/11 Jul Brisbane/373/11 aug Victoria/809/11 Jul Victoria/821/11 aug Victoria/631/11 sep LR Townsville/102/11 j un Brisbane/183/11 jun Bris bane/341/11 aug LR Victori a/356/11 oct Townsvil le/124/11 sep SthAustralia/196/11@ aug Newcastle/170/11 aug Townsvil le/104/11 jun S82P Bris bane/211/11lr jun S52N Si ngapore/kk472/11 oct cdcwis consin/26/11 oct $ SthAustrali a/68/11 aug NewCaledonia/11/11 aug Townsvi lle/95/11lr jun Darwin/82/11 mar Townsville/78/11LR apr Brisbane/67/11e feb Bris bane/141/11e apr Tasmania/21/11 Jun I122M Goroka/4/11 jul Goroka/6/11 jul Singappore/GP1806/11 nov nphl Singapore/51/11LR sep cdcstpetersburg/100/11e mar nimrstockholm/14/11 apr SthAustralia/2/11 jun SYDNEY/217/10LR sep Victori a/512/11 feb SongKhla/34/11LR feb Philippines/859/11 BRISBANE/70/11e feb Brisbane/190/11e jun Chris tchurch/18/11 aug Tas mani a/14/11e may V13I SthAustralia/4/11 jun Bris bane/158/11e apr Brisbane/121/11 mar LR Brisbane/500/11 jun Victor ia/581/11 aug@ Newc as tle/1/11lr apr Bri sbane/229/11lr jun Brunei/15/11 nimralborz/5607/10 dec Cambodia/69/11 nov L40I, V83M Cambodia/70/11 nov Cambodia/15/11 j ul Cambodia/11/11 jul Cambodia/53/11 nov G41R cdctexas/02/12 jan cdcmexico/210/12 jan N44S cdcmexico/56/11 dec cdcmexico/52/11 dec D199N, I396L cdcpennsy lvania/16/11 dec Brunei/16/11 feb Newcastl e/53/11 Newcastl e/201/11 Newcastl e/151/11 J V83 A Sydney /59/11 Aug H275Y E128G Newcastle/179/11 Y275H Sydney/525/11@ aug Perth/183/11 Sep Perth/194/11@ sep SthAustralia/24/11LR jul V62I, N386S Sydney/516/11 jul Perth/59/11 jul preg Hong Kong/3973/11 jun Sydney/17/11 may Phil ippines /959/11 jul I389T Philippines/850/11 jul Victoria/516/11 mpr Phil ippines /1343/11 Apr Singapore/TT769/11 nov S339P Singapore/TT617/11 sep A76V, I396T Singapore/GP1721/11 nov Phil ippines/477/11lr mar Perth/48/11 jul PM Perth/299/11 aug PM G77E Perth/293/11@ oct F 74L Perth/533/11e sep Perth/54/11 j ul piggery Darwin/103/11 oct Newcastle/58/11 Jul Canberra/10/11 jun Newc as tle/47/11lr jun S70N, V8 1G Sydney/12/11 may Brisbane/186/11 jun LR V241I, N369K P458S Newcastle/182/11 aug R257K Perth/39/11 Mar Wellington/1/11e may Bris bane/15/11 Sydney/56/11 aug cdcvoronezh/1/11e mar cdcflorida/35/11 dec nimrmendoz a/2672/11 jun $ cdckentucky/09/10e nov cdcarkansas/03/11 apr c dc Minnes ota/03/11 nimrcapetown/60/11 jun$ Victoria/730/11 dec Singapore/60/11 nov N386S,D451G Singapore/62/11 nov Singapore/TT773/11 nov siidcstockholm/1/12 jan R257K, I365T, N386S, I389M, I436V Perth/33/11 jan Macau/600129/11 feb c dcnew Mexico/05/11 feb Perth/30/11 mar S247N, S299A Darwin/70/11e mar Darwin/74/11 mar F322L Malaysia/478/11e apr 5b Malaysia/517/11e apr V106I Goroka/16/10e apr N248D BRISBANE/2013/09e jul M15I, N189S N4I, M373I I54 V, E287K CHRISTCHURCH/16/10e jul Victoria/663/10e dec 4 AUCKLAND/1/09e apr nimrgoteborg/1/11 apr 3 nimr LVIV/N6/09 aug Townsville/31/11 feb cdcalaska/14/11 mar 2 nimrcz ech Republic/32/11 jan cdc BAYERN/69/09 CALIFORNIA/07/09e $ Vaccine strain LR=low reactor $=serology antigen e=egg H275Y Sept/Oct 2011 Nov 2011 Dec 2011 Jan H1pdm sequences 1 7 5a

46 Decreasing stability WT Increasing stability NA mutations Suggests that viruses with N369K + V241I + N386S already in the NA (e.g. Newcastle strains) may be less compromised with the addition of the H275Y mutation than earlier A(H1N1)pdm 09 strains N369K and V241I are in the majority of strains currently analysed at WHOCC Melb and in Republic of Korea Dr. Kang (Poster presentation) These mutations are currently being investigated both in vitro and in vivo for their role in viral fitness Q308H G77E Fiji/3/12 jan Fiji/2/12 jan Christchurch/60/11 sep Brisbane/210/11LR jun Newcastle/163/11 Jul Brisbane/373/11 aug Victoria/809/11 Jul Victoria/821/11 aug Victoria/631/11 sep LR Townsville/102/11 j un Brisbane/183/11 jun Bris bane/341/11 aug LR Victori a/356/11 oct Townsvil le/124/11 sep SthAustralia/196/11@ aug Newcastle/170/11 aug Townsvil le/104/11 jun S82P Bris bane/211/11lr jun S52N Si ngapore/kk472/11 oct cdcwis consin/26/11 oct $ SthAustrali a/68/11 aug NewCaledonia/11/11 aug Townsvi lle/95/11lr jun Darwin/82/11 mar Townsville/78/11LR apr Brisbane/67/11e feb Bris bane/141/11e apr Tasmania/21/11 Jun I122M Goroka/4/11 jul Goroka/6/11 jul Singappore/GP1806/11 nov nphl Singapore/51/11LR sep cdcstpetersburg/100/11e mar nimrstockholm/14/11 apr SthAustralia/2/11 jun SYDNEY/217/10LR sep Victori a/512/11 feb SongKhla/34/11LR feb Philippines/859/11 BRISBANE/70/11e feb Brisbane/190/11e jun Chris tchurch/18/11 aug Tas mani a/14/11e may V13I SthAustralia/4/11 jun Bris bane/158/11e apr Brisbane/121/11 mar LR Brisbane/500/11 jun Victor ia/581/11 aug@ Newc as tle/1/11lr apr Bri sbane/229/11lr jun Brunei/15/11 nimralborz/5607/10 dec Cambodia/69/11 nov L40I, V83M Cambodia/70/11 nov Cambodia/15/11 j ul Cambodia/11/11 jul Cambodia/53/11 nov G41R cdctexas/02/12 jan cdcmexico/210/12 jan N44S cdcmexico/56/11 dec cdcmexico/52/11 dec D199N, I396L cdcpennsy lvania/16/11 dec Brunei/16/11 feb Newcastl e/53/11 Newcastl e/201/11 Newcastl e/151/11 J V83 A Sydney /59/11 Aug H275Y E128G Newcastle/179/11 Y275H Sydney/525/11@ aug Perth/183/11 Sep Perth/194/11@ sep SthAustralia/24/11LR jul V62I, N386S Sydney/516/11 jul Perth/59/11 jul preg Hong Kong/3973/11 jun Sydney/17/11 may Phil ippines /959/11 jul I389T Philippines/850/11 jul Victoria/516/11 mpr Phil ippines /1343/11 Apr Singapore/TT769/11 nov S339P Singapore/TT617/11 sep A76V, I396T Singapore/GP1721/11 nov Phil ippines/477/11lr mar Perth/48/11 jul PM Perth/299/11 aug PM G77E Perth/293/11@ oct F 74L Perth/533/11e sep Perth/54/11 j ul piggery Darwin/103/11 oct Newcastle/58/11 Jul Canberra/10/11 jun Newc as tle/47/11lr jun S70N, V8 1G Sydney/12/11 may Brisbane/186/11 jun LR V241I, N369K P458S Newcastle/182/11 aug R257K Perth/39/11 Mar Wellington/1/11e may Bris bane/15/11 Sydney/56/11 aug cdcvoronezh/1/11e mar cdcflorida/35/11 dec nimrmendoz a/2672/11 jun $ cdckentucky/09/10e nov cdcarkansas/03/11 apr c dc Minnes ota/03/11 nimrcapetown/60/11 jun$ Victoria/730/11 dec Singapore/60/11 nov N386S,D451G Singapore/62/11 nov Singapore/TT773/11 nov siidcstockholm/1/12 jan R257K, I365T, N386S, I389M, I436V Perth/33/11 jan Macau/600129/11 feb c dcnew Mexico/05/11 feb Perth/30/11 mar S247N, S299A Darwin/70/11e mar Darwin/74/11 mar F322L Malaysia/478/11e apr 5b Malaysia/517/11e apr V106I Goroka/16/10e apr N248D BRISBANE/2013/09e jul M15I, N189S N4I, M373I I54 V, E287K CHRISTCHURCH/16/10e jul Victoria/663/10e dec 4 AUCKLAND/1/09e apr nimrgoteborg/1/11 apr 3 nimr LVIV/N6/09 aug Townsville/31/11 feb cdcalaska/14/11 mar 2 nimrcz ech Republic/32/11 jan cdc BAYERN/69/09 CALIFORNIA/07/09e $ Vaccine strain LR=low reactor $=serology antigen e=egg H275Y Sept/Oct 2011 Nov 2011 Dec 2011 Jan H1pdm sequences 1 7 5a 6

47 Summary Overall the frequency of oseltamivir resistance remains low ( 1%) But the no. of resistant strains in untreated patients has (USA, UK, Asia-Pacific) Suggesting that there is an increased capacity of H275Y oseltamivir-resistant viruses to transmit compared with at the start of the pandemic The cluster of cases in Newcastle and HNE region represents the largest known spread of oseltamivir-resistant A(H1N1)pdm09 (20/85; 24% in July) Majority of cases within 50 km radius, but detected up to 4000 km away No known spread outside of Australia, with no widespread resistance in NH (11/12) Further studies are ongoing to determine if currently circulating strains are more permissive to the H275Y resistance mutation Laboratories should continue to conduct testing for H275Y A(H1N1)pdm09 variants Important to collect patient information, denominator data, to evaluate whether resistant viruses are spreading in the community If clusters like Newcastle are to be detected whilst they are occurring (and not after the event), regular testing or submission of viruses to testing laboratories is necessary... discussion: ideal time to ship, budget considerations, etc.

48 Acknowledgements Thank you to all WHO National Influenza Centres and other submitting laboratories for the provision of influenza isolates and epidemiological data Newcastle cluster Hunter New England Population Health Kate Hardie Maggi Osbourne Tony Merritt Craig Dalton David Durrheim Hunter Area Pathology Service Noelene Wilson Nichole Gehrig Rod Givney University of Newcastle Peter Wark Bioinformatics Institute, A-STAR, Singapore Raphael Lee Sebastian Maurer-Stroh Westmead Hospital, Sydney Dominic Dwyer Bin Wang PathWest, Perth David Smith Avram Levy NCIRS, Sydney Robert Booy Rashmi Dixit Staff of WHO CC for Influenza The WHO Collaborating Centre for Reference and Research on Influenza, Melbourne is supported by the Australian Government Department of Health and Ageing

49

50 NA inhibitor sensitivity of H275Y variant A(H1N1)2009 cases in Hunter New England region Virus Mean of HNE H275Y A(H1N1) 2009 viruses (n=11) vs Mean of HNE sensitive A(H1N1) 2009 viruses (n=65) Zanamivir Mean IC 50 ± SD (nm) Oseltamivir carboxylate fold Mean IC 50 ± diff b SD (nm) Peramivir fold Mean IC 50 ± diff b SD (nm) 0.3 ± ± ± ± ± ± fold diff b Mean of all sensitive A(H1N1)2009 viruses (n=3579) 0.3 ± ± ± 0.1 a - a Mean and standard deviation of peramivir IC 50 values based on analysis of n=273 isolates b Fold difference based on comparison with mean IC 50 of all A(H1N1)2009 viruses