Public Health Wales CDSC Weekly Influenza Surveillance Report Wednesday 21 st January 2015 (covering week )

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1 The The Influenza B in certain countries8 Public Health Wales CDSC Weekly Influenza Surveillance Report Wednesday 21 st January 215 (covering week 3 215) Current level of activity: Low Trend: Decreased compared to last week Dominant type: Influenza A(H3) News: Data suggests influenza is circulating in Wales Update Middle East respiratory syndrome coronavirus (MERS-CoV) (page 3) Update Influenza A(H7N9) in China (page 4) Key points Wales Surveillance indicators suggest that influenza is now circulating at low levels in the community in Wales. The use of antivirals for treatment and prophylaxis of influenza should now be considered in line with NICE guidance. The consultation rate for influenza in Wales during week 3 (week ending 18/1/215) reported through the GP Sentinel Surveillance of Infections Scheme was 16.9 consultations per 1, practice population. The provisional consultation rate was highest in patients aged years of age (3.5 per 1, practice population). The consultation rate decreased compared to the previous week (22.5 per 1,), but remains above the Moving Epidemic Method (MEM) threshold of 9.7 consultations per 1,, and still below the historical threshold for normal seasonal activity (25 consultations per 1, per week). The total number of consultations with Out of Hours (OOH) doctors in Wales, reported to Public Health Wales during week 3 was 11,391(compared to 11,975 in week 2), The proportion of respiratory-related consultations with OOH doctors increased to 17.9% (Figure 6). During week 3, six surveillance samples from patients with influenza-like illness were submitted by sentinel GPs (Figure 3). Samples are routinely tested for influenza A, influenza B, RSV, rhinovirus, parainfluenza, adenovirus, mycoplasma, human metapneumovirus, enterovirus, bocavirus, and coronaviruses. Four samples tested positive for influenza A(H3) (two patients aged years and two patients aged years, all from South East Wales), and one tested positive for RSV (a patient aged years from South East Wales), and the other sample was negative for routinely tested respiratory pathogens. A number of confirmed outbreaks of influenza A(H3) have been reported to Public Health Wales, the majority of these outbreaks have been in hospital or care home settings. During week 3, 1 outbreaks of acute respiratory illness, six in care homes and four in hospitals, were reported to Public Health Wales. During week 3, 172 specimens were received and tested by Public Health Wales Microbiology, from non-sentinel GP and hospitalised patients with influenza-like symptoms, 41 (24%) tested positive for influenza A(H3), 2 tested positive for RSV, five tested positive for rhinovirus, three tested positive for human metapneumovirus, three tested positive for adenovirus, and two tested positive for parainfluenza. Early evidence from the UK and Europe suggests that some influenza A(H3N2) viruses detected so far this season have drifted, making them different to the influenza A(H3N2) virus which is contained in the seasonal influenza vaccine. Although the differences potentially make the vaccine less effective against these particular influenza A(H3N2) viruses, seasonal influenza vaccination is still important for those at risk because other influenza viruses which are also currently circulating remain similar to the viruses contained in the vaccine. Public Health England have reported that the majority of influenza A(H3N2) viruses detected and characterised from England and Wales are similar to the virus contained in the seasonal influenza vaccine, however, as at 15/1/215, 12 (21%) displayed differences. The vast majority of influenza viruses - 1 -

2 tested to date for oseltamivir and zanamivir susceptibility by Public Health England were sensitive to these antivirals. Public Health Wales and colleagues throughout the UK continue to closely monitor the situation. Key points Influenza vaccination rates in Wales Influenza vaccination rates in Wales reported through Audit+, as at 13/1/215: 67.1% of patients aged 65 years and older have been vaccinated against influenza (Health Board range 63.6% to 69.4%). 48.2% of patients aged six months to 64 years in at-risk groups have been vaccinated against influenza (HB range 42.6% to 51.9%). 36.1% of children aged 2 to 4 years have been vaccinated against influenza (HB range 3.7% to 44.3%). As at the end of December 214, 41.5% of NHS staff have been vaccinated against influenza (Health Board / NHS Trust range 24.6% to 67.7%). Key points UK and Europe Based on the latest data available (15/1/15): In week 2 overall influenza GP consultations increased in Scotland (27.6 per 1,) and Northern Ireland (47.6 per 1,). The weekly ILI consultation rate through GP In Hours Syndromic Surveillance for England remained elevated in week 2 (21.3 per 1,). One-hundred and ten samples tested positive for influenza through the English GP sentinel schemes in week 2 (92 influenza A(H3), nine H(H1N1)pdm9, five influenza A(not subtyped), and four influenza B); and 425 influenza positive detections were reported through Public Health England s DataMart scheme (355 influenza A(H3), 51 influenza A(not subtyped), eight influenza A(H1N1)pdm9 and 11 influenza B). UK summary data are available from the Public Health England National Influenza Report. The WHO and the European Centre for Disease Prevention and Control (ECDC) report that during week 2 the number of countries in the European region with increased influenza activity continued to rise. During week 2 a total of 1195 sentinel specimens were tested for influenza, 34 of which were positive (196 were positive for influenza A(H3N2), 58 influenza A(H1N1)pdm9, 31 influenza A (not subtyped), and 55 influenza B). For more information on European level influenza surveillance see Flu News Europe: World update The WHO report that, as of 12/1/15, global influenza activity continued to increase in the northern hemisphere with influenza A(H3N2) viruses predominating so far. In North America, the influenza season was ongoing with influenza activity still increasing in most areas. Influenza A(H3N2) was the predominant virus. In Europe influenza activity was still low, but the season seemed to have started. In eastern Asia, influenza activity increased with influenza A(H3N2) virus predominating. In northern and western Africa influenza activity increased with influenza B virus predominant. In tropical countries of the Americas, influenza activity increased in some countries of the Caribbean, decreased in Central America and was low in the tropical countries of South America. In tropical Asia, influenza activity increased slightly but remained low with influenza B predominating. In the southern hemisphere, influenza activity remained at low levels. The WHO recommendation on the composition of influenza vaccines for the southern hemisphere 215 was announced on 25 September 214. The recommendation and associated technical report are posted at the WHO website: Based on FluNet reporting (as of 9/1/215), during weeks 51 to 52 (14/12/214 27/12/214) National Influenza Centres and other national influenza laboratories from - 2 -

3 8 countries, areas or territories reported influenza surveillance data. The WHO Global Influenza Surveillance and Response System laboratories tested more than 96,535 specimens, of which 23,421 were positive for influenza viruses. Of these, 22,129 were typed as influenza A (163 influenza A(H1N1)pdm9, 9,211 influenza A(H3N2) and 12,755 influenza A(not sub-typed)) and 1,292 influenza B (of the characterised influenza B viruses 423 belonged to the B-Yamagata lineage and nine to the B-Victoria lineage). Source: WHO influenza update: Update on influenza activity in North America The USA Centers for Disease Control and Prevention (CDC) report that during week 1 (4/1/215 1/1/215) influenza activity remained elevated in the United States. Nationally, 5,284 (2.2%) out of 26,24 specimens tested positive for influenza. Of the influenza positive specimens reported, 1,868 were influenza A(H3), seven were influenza A(H1N1)pdm29, 3,176 were influenza A(not sub-typed) and 233 were influenza B. Of the 349 influenza A(H3N2) viruses characterised to date, 65% displayed differences to the influenza A(H3N2) virus contained in the northern hemisphere 214/15 influenza vaccine. Most of the viruses which displayed genetic or reactivity differences were antigenically similar to the A/Switzerland/ /213 virus. Weekly surveillance report on the flu season in the USA is available from: The Public Health Agency of Canada reported that during week 1 national ILI consultation rate decreased to 5.1 consultations per 1, patient visits, which is still above expected levels for this time of year. During week 1, there were 4,45 laboratory detections of influenza reported, 4,32 influenza A (3,433 influenza A(H3), and 887 influenza A (not subtyped)) and 13 influenza B. Source: Public Health Agency of Canada Middle East respiratory syndrome coronavirus (MERS-CoV) latest update from WHO and ECDC On 2/1/15, WHO reported five additional laboratory-confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection, including one death. Globally, 955 laboratory confirmed cases of human infection with MERS-CoV, including at least 351 related deaths, have officially been reported to WHO. Based on the current situation and available information, WHO encourages all member states to continue their surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns. Health care providers are advised to be vigilant among recent travellers returning from the Middle East who develop SARI. Health care workers should be trained and/or refreshed with skills on infection prevention and control to decrease the risk of transmission from an infected patient to others. It is currently thought people with diabetes, renal failure, chronic lung disease and immunocompromised persons are considered to be at high risk of severe disease from MERS-CoV infection. These people are advised to avoid close contact with animals, particularly camels, when visiting farms, markets or barn areas where the virus is known to be potentially circulating. It is advised that people should avoid drinking raw camel milk or camel urine, or eating meat that has not been properly cooked. Updates are available from the WHO Global Alert and Response website: An updated rapid risk assessment on MERS-CoV has been published by ECDC. The report provides an epidemiological summary of the MERS-CoV situation and an update on the growing evidence suggesting that dromedary camels are a host species for the MERS-CoV and may play a role in the transmission chain. The assessment also contains advice for EU residents travelling to, or returning from the Arabian Peninsula, in addition to advice for the international public health community. For more information - 3 -

4 from the updated rapid risk assessment see: WHO also provide advice on MERS-CoV for pilgrimages: Human infection with avian influenza A(H7N9), China latest update from WHO On 19/1/215, the WHO reported an additional 15 laboratory-confirmed case of human infection with novel avian influenza A(H7N9) virus in China, including three deaths. So far, the risk for ongoing human-to-human transmission is low. The risk of international spread of avian influenza A(H7N9) is considered to be low at present. However, it is important that clinicians are aware of the possibility of human infection with animal influenza, in persons presenting with severe acute respiratory disease, while travelling or soon after returning from an area where avian influenza is a concern. World Health Organisation is following this event closely with the Chinese authorities and updates are available from the WHO Global Alert and Response website:

5 Summary of influenza activity in Wales Figure 1. Clinical consultation rate per 1, practice population in Welsh sentinel practices (as of 21/1/15). 2 Consultation rate per 1, MEM threshold** Higher than average seasonal activity Normal seasonal activity Low activity Week ** The Moving Epidemic Method has been adopted by the European Centre for Disease Prevention and Control to calculate thresholds for GP ILI consultations for seasonally expected influenza activity in a standardised approach across Europe. The threshold calculated for Wales ILI consultation rates is 9.7 per 1,. Figure 2. Historical clinical consultation rate per 1, practice population in Welsh sentinel practices (week week 3 215). Consultation rate per 1, Epidemic activity Higher than average seasonal (winter) activity Normal seasonal activity (winter) * October 1996 April 1997 October 1997 April 1998 October 1998 April 1999 October 1999 April 2 October 2 April 21 October 21 April 22 October 22 April 23 October 23 April 24 October 24 April 25 October 25 April 26 October 26 April 27 October 27 April 28 October 28 April 29 October 29 April 21 October 21 April 211 October 211 April 212 October 212 April 213 October 213 April 214 October 214 *Reporting changed to Audit+ surveillance system - 5 -

6 Table 1. Age-specific consultations (per 1,) for influenza in Welsh sentinel practices, week week (as of 21/1/215). Age group < Total Figure 3. Specimens submitted for virological testing by sentinel GPs as of 21/1/215, by week of sample collection, week week Influenza A positive Influenza B positive RSV positive Rhinovirus positive Adenovirus positive Parainfluenza positive Mycoplasma positive Human metapneumovirus Enterovirus Bocavirus Coronaviruses Negative* Sentinel GP consultation rate 2 Rate per 1, Sample test results Week ( ) * Tested negative for influenza, adenovirus, rhinovirus, RSV, adenovirus, parainfluenza, mycoplasma, human metapneumovirus, enterovirus, bocavirus and coronaviruses

7 Figure 4. Specimens submitted for virological testing for hospital patients and nonsentinel GPs as of 21/1/215, by week of sample collection, week week Influenza A positive Influenza B positive RSV positive Rhinovirus positive Adenovirus positive Parainfluenza positive Mycoplasma positive Human metapneumovirus Negative* dummy 25 Sample test results Week ( ) Combined data for tests carried out in Public Health Wales Microbiology: Cardiff laboratory, provided by Public Health Wales Microbiology Cardiff Specialist Virology Centre. * Tested negative for influenza, adenovirus, rhinovirus, RSV, adenovirus, parainfluenza, mycoplasma and human metapneumovirus Adenovirus data not available after week 46 Update on influenza immunisation in Wales Table 2. Uptake of influenza immunisation in patients aged 65y and older and in those aged 6m to 64y at clinical risk, data correct as at 21/1/215. Health Board Patients aged 65y and older Immunised Denominator Data source: General Practice data, extracted using the Audit+ Data Quality System Uptake (%) Patients aged 6m to 64y at risk Immunised Denominator Uptake (%) Abertawe Bro Morgannwg UHB Aneurin Bevan UHB Betsi Cadwaladr UHB Cardiff and Vale UHB Cwm Taf UHB Hywel Dda UHB Powys Teaching HB Wales

8 Figure 5. Uptake of influenza vaccine in patients aged 65y and older and in those aged 6m to 64y at clinical risk, data correct as at 21/1/ y and older 6m to 64y at risk Table 3. Uptake of influenza vaccine in patients by clinical risk group, data correct as at 21/1/215. Risk Group Immunised Denominator Uptake (%) 65y and older 399,11 594, At clinical risk 6m to 64y 156, , Chronic heart disease 6m to 64y 26,757 56, Chronic kidney disease 6m to 64y 8,8 15, Chronic liver disease 6m to 64y 3,28 7, Chronic respiratory disease 6m to 64y 8,883 17, Diabetes 6m to 64y 47,154 74, Immune-suppression 6m to 64y 11,547 2, Neurological conditions 6m to 64y 14,774 32, Pregnant women at clinical risk 1,494 2, Pregnant women not at risk 1,115 24, Table 4. Influenza immunisation uptake in NHS staff up to the end of December 214, by Health Board. Health Board Immunised Total Staff Staff with direct patient contact 1 Denominator Aneurin Bevan UHB Abertawe Bro Morgannwg UHB Betsi Cadwaladr UHB Cardiff and Vale UHB Cwm Taf UHB Hywel Dda UHB Powys Teaching HB Velindre NHS Trust Welsh Ambulance Service NHS Trust Public Health Wales NHS Trust Wales Combined figures for: Additional Prof Scientific and Technical, Additional Clinical Services, Allied Health Professionals, Medical and Dental, Nursing & Midwifery Registered staff groups. 2 Data submitted by Health Boards on the number of Public Health Wales NHS Trust staff immunised Uptake (%) Immunised Denominator Uptake (%)

9 Out of Hours consultations and calls to NHS Direct Wales Figure 6. Weekly total consultations to Out of Hours services in Wales and numbers of respiratory-related diagnoses (as of 21/1/215). 25 Total OOH consultations % of consultations respiratory related Respiratory-related OOH consultations Consultations % of consultations 22/1/212 4/3/212 15/4/212 27/5/212 8/7/212 19/8/212 3/9/212 11/11/212 23/12/212 3/2/213 17/3/213 28/4/213 9/6/213 21/7/213 1/9/213 13/1/213 24/11/213 5/1/214 16/2/214 3/3/214 11/5/214 22/6/214 3/8/214 14/9/214 26/1/214 7/12/214 18/1/215 Figure 7. Influenza related calls to NHS Direct Wales 1 (as a percentage of total calls) from week week (as of 21/1/215). Percentage of total calls (%) Jan Feb Mar Apr-11 9-May-11 6-Jun-11 4-Jul-11 1-Aug Aug Sep Oct Nov Dec Jan Feb Mar-12 9-Apr-12 7-May-12 4-Jun-12 2-Jul-12 3-Jul Aug Sep Oct Nov Dec Jan Feb Mar-13 8-Apr-13 6-May-13 3-Jun-13 1-Jul Jul Aug Sep Oct Nov Dec Jan-14 1-Feb-14 1-Mar-14 7-Apr-14 5-May-14 2-Jun-14 3-Jun Jul Aug Sep-14 2-Oct Nov Dec Jan-15 Week commencing During week 3, the percentage of total calls to NHS Direct Wales which were influenza-related decreased to 9.9% (Figure 7). 1 Data supplied by Health Statistics and Analysis Unit, Welsh Government. Flu related calls are the sum of calls recorded as 'cold/flu', 'cough', 'headache', 'fever' and 'sore throat'

10 Links: Public Health Wales influenza surveillance webpage: NICE influenza antiviral usage guidance: Wales influenza information: England influenza surveillance: Scotland influenza surveillance: Northern Ireland influenza surveillance: European Centre for Communicable Disease: European influenza information: Advice on influenza immunisation (for NHS Wales users) For further information on this report, please Public Health Wales using: - 1 -