Weekly pandemic flu media update

10 December 2009

KEY POINTS

• The consultation rate for flu-like illness in England from the Royal College of General Practitioners (RCGP) scheme has decreased slightly to 33.1 per 100,000 in week 49 compared to 38.6 in week 48. This remains above the English baseline threshold of 30/100,000.
• The estimated cases self referring to the National Pandemic Flu Service have shown decreases in all areas of assessments, authorisations and collections. This is across all age groups. 
• Interpretation of data to produce estimates on the number of new cases continues to be subject to a considerable amount of uncertainty. HPA modelling gives an estimate of 11,000 new cases in England last week (range 6,000 to 24,000) which represents a significant decrease from the previous week.    
  This estimate incorporates data from National Pandemic Flu Service and GP consultations.
• The HPA estimates a cumulative total number of cases of 795,000 (with a range 380,000 to 1,665,000) since the pandemic began.
  

Following the move from laboratory testing for confirmation of swine flu to clinical diagnosis of cases, the level of flu in the community is being monitored using a range of surveillance mechanisms, including the RCGP consultation rates, QSurveillance®, and the National Pandemic Flu Service.

A more detailed UK weekly epidemiology update can be accessed at:
www.hpa.org.uk/swineflu/surveillance&epidemiology

CLINICAL INDICATORS
Clinical data are obtained from GP surgeries that report the weekly and daily consultations for flu-like illness and other acute respiratory illness.

Current estimated weekly Royal College of General Practitioners (RCGP) consultation rates of flu-like illness

From a network of approximately 100 general practices covering a population of approximately 900,000 with an equal distribution within each of three defined reporting regions; North, Central and South.

In week 49 (ending 6 December) GP consultation rates for flu-like illness in England have shown a very slight decrease compared to the previous week (38.6 per 100,000 in week 48 to 33.1 per 100,000 in week 49) which is still above the English baseline threshold of 30/100,000.

Figure 1: Current estimated weekly RCGP consultation rates of flu-like illness

QSurveillance®
Set up by the University of Nottingham and EMIS (the main supplier of general practice computer systems within the UK) in collaboration with the Health Protection Agency, QSurveillance® is a not-for-profit network of over 3,300 general practices covering a total population of almost 22 million patients (> 25% of the UK population).

The weekly QSurveillance® flu-like illness consultation rate showed a slight decrease from 44.9 per 100,000 in week 48 to 38.6 per 100,000 in week 49. The weekly rate for flu-like illness in all SHA regions show general decreasing trends.  A decrease is also seen in most age groups with some increases in the

NB: QSurveillance® is based on data from 43% of England's population (about 3000 practices), 10% of the population in Wales, 17% in Northern Ireland, and 0% in Scotland.

Figure 2: QSurveillance® - weekly consultation rate for flu-like illness in England, Wales and Northern Ireland (all ages)

Figure 3: QSurveillance® - weekly consultation rate for influenza-like illness by English SHA (all ages)

Figure 4: QSurveillance influenza-like illness rate by age band in week 49 (ending 6 December)

SYNDROMIC SURVEILLANCE

NHS Direct
On 23 July the National Pandemic Flu Service was implemented. This had an impact on the number of 'cold/flu' calls received through the routine NHS Direct service. For this reason, data from NHS Direct do not reflect the true pattern of cold/ flu callers and so are not currently an accurate surveillance tool.

VIRAL CHARACTERISTICS
To date (as of 9 December 2009) 4,214 viruses have been analysed by the HPA Centre for Infections for the genetic marker commonly associated with resistance to oseltamivir in seasonal H1N1 flu (H274Y). 25 viruses have been found to carry this marker in the UK with three of these, through additional testing, showing evidence of resistance when viral growth is tested in the presence of oseltamivir. These viruses are still sensitive to zanamivir. In addition, 293 specimens have been fully tested for susceptibility to antivirals. 

Information on medical history was available for 17 cases, all of whom had an underlying medical condition: 14 were immunosuppressed and three had chronic respiratory or neurological illnesses.

Testing of samples, taken before and after treatment with oseltamivir, show that the antiviral resistance in 14 of the cases was treatment-induced, four are probably acquired through person to person transmission, and in four cases the origin of the resistant virus is still under investigation.

The agency is continually assessing its advice to government on health protection policies such as antiviral use. Currently there is no requirement to change existing guidance.

There have been no significant changes in the virus.

SEVERITY
Disease severity continues to be monitored. The disease is generally mild in most people so far, but is proving severe in a small minority of cases.

Swine flu hospitalisations in England: 636 patients (currently hospitalised as of 8am on 9 December). 

Deaths - the number of deaths related to swine flu in England is 191 (This figure represents the number of deaths in individuals with swine flu but does not represent the number of deaths that can be attributed to swine flu).

INTERNATIONAL SUMMARY

Confirmed global deaths reported by ECDC (Update 17:00 CEST 9 December 2009)

Total deaths reported 10,074
 In the last 7 days, the total number of deaths reported globally has increased by 15% on the previous week.

NB: Laboratory confirmed case numbers are no longer being reported for most countries as they do not give a representative view of the actual number of cases worldwide.

The World Health Organization (WHO) reported on 4 December that for:

• Tropical regions: transmission of flu remains geographically widespread, but disease activity is declining in the tropical regions of the Americas and Caribbean, apart from focal areas of increasing activity in Jamaica, Venezuela and Ecuador.    
• Central and Western Asia: disease activity continues to increase in Kazakhstan, Kyrgyzstan, Uzbekistan, Iran and Iraq, while activity may have peaked in Israel, Jordan and Afghanistan.
• Temperate northern hemisphere regions: The early arriving winter flu season continues to intensify across central Europe and parts of central, eastern and southern Asia. In North America and much of western and northern Europe disease activity has peaked, or is currently peaking. 
  • In Europe: widespread and intense transmission of swine flu virus continues to be observed across much of the continent.  Flu activity has peaked in a number of western and northern European countries, but continues to increase in central European countries between the Baltic and the Balkans and from Germany to Romania.  In Eastern Europe, disease activity has recently peaked in Ukraine, Belarus, Bulgaria and the Republic of Moldova.  In the Russian Federation, disease remains active and intense in some regions, with an overall increasing trend.  A moderate impact on the healthcare system has been reported in parts of northern and eastern Europe. 
  • In the United States and Canada: transmission of flu remains active and geographically widespread, although disease activity appears to have peaked.
• Temperate southern hemisphere region: very little swine flu activity reported.
• Eastern and southern Asia: increasing respiratory disease activity was reported in southern China and Japan.  A recent decline in activity was reported in northern China.  In South and Southeast Asia, flu activity continues to increase in the north-west of India, Nepal, Sri Lanka and Cambodia, while activity in the rest of the region remains low.
• Africa: The swine flu virus continues to be isolated from all parts of the continent, and there is evidence of continued co-circulation of seasonal H3N2 viruses.

More information on the latest global situation can be found on the WHO website at: http://www.who.int/csr/don/2009_12_04/en/index.html

ENDS

Notes to editors

General infection control practices and good respiratory hand hygiene can help to reduce transmission of all viruses, including swine flu. This includes:

• Maintaining good basic hygiene, for example washing hands frequently with soap and water to reduce the spread of virus from your hands to face or to other people.
• Cleaning hard surfaces (e.g. door handles) frequently using a normal cleaning product.
• Covering your nose and mouth when coughing or sneezing, using a tissue when possible.
• Disposing of dirty tissues promptly and carefully.
• Making sure your children follow this advice. 

Further information on swine flu is available on the Health Protection Agency's website at www.hpa.org.uk/swineflu.

For media enquiries only please contact the Health Protection Agency's Centre for Infections press office on:  

020 8327 7080   
020 8327 7097  
020 8327 7098
020 8327 6690  
020 8327 6647

Last reviewed: 10 December 2009