Weekly pandemic flu media update

27 August 2009

KEY POINTS

• This week there has been a further reduction in the rates of flu-like illness and related activity.
• Weekly GP consultation rates continued to decrease over the last week in England.  
• The majority of cases continue to be mild. There is no sign that the virus is changing. It is not becoming more severe or developing resistance to anti-virals.
• 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 5,000 new cases in England last week (range 3,000 to 12,000). There has been a decrease in estimated number of cases in all age groups and in all regions.
  This estimate incorporates data from National Pandemic Flu Service and GP consultations.
  

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 34 (ending 23 August) GP consultation rates for flu-like illness in England decreased compared to the previous week (21.1 per 100,000 to 16.5 per 100,000). The rate continued to decrease in North (17 per 100,000) and Central (19 per 100,000) regions but stayed stably low in the South (15 per 100,000). The rate has decreased in all age groups.

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 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 decreased from 30.8 per 100,000 to 19.3 per 100,000 in week 34. The daily rate for flu-like illness for the last few days remained low for all regions.

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® - daily consultation rate for influenza-like illness by English SHA (all ages)

Figure 4: QSurveillance influenza-like illness rate by age band in week 34 (ending 23 August)

The latest weekly flu-like illness rates show that the highest consultation rates were in the <1 15-24="15-24" group.="group." NB:="NB:" <1="<1" year="year" age="age" group="group" are="are" not="not" considered="considered" by="by" the="the" National="National" Pandemic="Pandemic" Flu="Flu" Service="Service" and="and" always="always" referred="referred" to="to" a="a" GP.</p="GP.</p" />

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

Viral characteristics (including antiviral susceptibility (as at 26/08/09): Testing for antiviral susceptibility is carried out by the Agency's Respiratory Virus Unit, Centre for Infections, in Colindale. 719 viruses have been analysed for the marker commonly associated with resistance to oseltamivir in seasonal influenza (H274Y); none were found to carry this marker. In addition, 210 specimens have been fully tested for susceptibility; all were found to be sensitive to oseltamivir and zanamivir.  

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: 218 patients (currently hospitalised as of 8am on 26 August).

Deaths - the number of deaths related to swine flu in England is 57. (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 cases and deaths reported by ECDC (Update 17:00 CEST 25 August 2009)

Grand total of cases confirmed *: 254,947

Total deaths reported: 2,594

* This figure represents the number of laboratory confirmed cases and is therefore not representative of the actual number of cases worldwide.

In the last 7 days, cases reported globally have increased by 8% and the number of deaths by 21%.

Key points:

Americas
WHO continues to report a decrease or no change in the trend of respiratory activity in the Americas in week 32 (9 Aug 09) compared to the previous week.  Countries showing increasing trends are Bolivia, Honduras, and Haiti. Intensity of acute respiratory disease in the population remains low or moderate in most countries with Argentina, Costa Rica, El Salvador, Guatemala, and Paraguay showing high intensity and Mexico very high intensity. Geographical spread is widespread in most countries and impact on healthcare services is low or moderate.

Europe
In the latest Euroflu bulletin, all countries reported low or moderate intensity indicating a normal or slightly increased proportion of their populations were affected by respiratory illness.  Widespread activity was reported for Austria, Israel, England and Sweden http://www.euroflu.org/index.php. The majority of new confirmed cases are being reported from Germany (ECDC).

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: 19 May 2010