Weekly epidemiological update

Summary for 04 February 2010 (Week 05)

• Pandemic influenza activity is generally decreasing across the UK.
• In week 04 (ending 31 January), the weekly influenza/influenza-like illness (ILI) consultation rate decreased or remained stable in England, Wales and N. Ireland and increased slightly in Scotland.
• The National Pandemic Flu Service (NPFS) continues to issue antiviral drugs to people in England with an influenza-like illness who call or log onto the internet site. The number of assessments and antiviral collections through this service have decreased over the past week. This service will continue until 11 February 2010; from this date onwards, antivirals will be authorised via health care professionals.
• A decrease in respiratory syncytial virus detections has been observed recently though GP consultation rates for acute bronchitis have increased from week 03 to 04, mainly in people aged under 5 years and 65 years or over.
• The main influenza virus circulating in the UK continues to be the pandemic (H1N1) 2009 strain, with few influenza H1 (non-pandemic), H3 and B viruses detected. Thirty-eight of 5,174 pandemic viruses tested have been confirmed to carry a mutation which confers resistance to the antiviral drug oseltamivir; three are phenotypically resistant to the drug but retain sensitivity to zanamivir.
• The weekly number of pandemic influenza cases reported as admitted to hospital has decreased recently. There have been 411 deaths reported due to pandemic (H1N1) 2009 in the UK.
• The UK pandemic influenza vaccination programme continues for people at high risk for severe disease, health-care workers and healthy children aged between 6 months and 5 years. For further information see the Department of Health website.
• According to the World Health Organisation (29 January), virus transmission remains active in several later affected areas, particularly in North Africa, limited areas of eastern and south eastern Europe, and in parts of South and East Asia. Pandemic virus accounted for 54% of all influenza virus detections (decreased from 73% in the previous week) and influenza B accounted for 36%. The influenza B detections have mainly been reported from China, where they account for 49% of all detections.