Weekly pandemic flu media update

5 November 2009

KEY POINTS

• The consultation rate for flu-like illness in England from the Royal College of General Practitioners (RCGP) scheme decreased to 37.7 per 100,000 in week 44 compared to 42.8 in week 43.
• The main burden of flu-like illness nationally in week 44 is in the <1 and="and" 1-4="1-4" years="years" age="age" groups.</li="groups.</li" />
• This week, the antiviral collection numbers in the National Pandemic Flu Service have decreased in the 5-14 and 15-24 years 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 84,000 new cases in England last week (range 42,000 to 181,000). This represents an 8% increase on 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 621,000 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 44 (ending 1 November) GP consultation rates for flu-like illness in England have shown a small decrease compared to the previous week (42.8 per 100,000 in week 43 to 37.7 per 100,000 in week 44).

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 showed a slight decrease from 49.2 per 100,000 in week 43.to 48.5 per 100,000 in week 44. The weekly rate for flu-like illness in all SHA regions and all age groups showed a mixed picture with some increasing and others decreasing.

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 44 (ending 1 November)

The latest weekly flu-like illness rates show that the highest flu-like illness consultation rates were in the <1 1-4="1-4" year-old="year-old" groups.="groups." Compared="Compared" with="with" 43="43" this="this" week="week" (week="(week" 44)="44)" rates="rates" have="have" increased="increased" most="most" groups,="groups," but="but" decreased="decreased" school="school" children="children" young="young" adults="adults" in="in" the="the" 5-14="5-14" and="and" 15-24="15-24" years="years" age="age" bands.="bands." </p="</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

To date (as of 4 November 2009) 2,437 viruses have been analysed by the Centre for Infections for the genetic marker commonly associated with resistance to oseltamivir in seasonal H1N1 flu (H274Y). Three viruses have been found to carry this marker in the UK. In addition, 299 specimens have been fully tested for susceptibility. 

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: 848 patients (currently hospitalised as of 8am on 4 November). 

Deaths - the number of deaths related to swine flu in England is 105 (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 4 November 2009)

Total deaths reported: 6,255

In the last 7 days, the total number of deaths reported globally has increased by 5% - compared to the 12% increase reported last 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 30 October that for:

• Tropical regions: influenza activity remains active in many countries in the Americas, most notably in several Caribbean countries. Overall transmission continues to decline in most but not all parts of the tropical zone of South and Southeast Asia.
• Temperate southern hemisphere regions: no significant pandemic related activity has been reported from these regions in the past week.
• Temperate northern hemisphere regions: influenza activity continues to intensify, marking an unusually early start to winter influenza season in some countries. In North America, the US and parts of western Canada continue to report high rates of influenza-like-illness (ILI) and numbers of pandemic H1N1 2009 virus detections; Mexico has reported more confirmed cases since September than during the springtime epidemic. In western Europe, high rates of ILI and proportions of respiratory specimens testing positive for pandemic H1N1 2009 have been observed in at least four countries: Iceland, Ireland, Belgium, and the Netherlands. Many other countries in Europe and western and central Asia are showing evidence of early influenza transmission, including in Spain, Austria, parts of northern Europe, Russia, and Turkey. In Japan, influenza activity has also increased sharply, especially on the northern island, approximately 10 weeks ahead of the usual start of the winter influenza season.

More information on the latest global situation can be found on the WHO website at: http://www.who.int/csr/don/2009_11_03/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: 3 June 2010