Weekly pandemic flu media update (6 August 2009)

6 August 2009

KEY POINTS

• There is a clear indication that the number of cases in England has decreased significantly in the last week.
• Weekly GP consultation rates decreased over the last week in England, coinciding with the first full week of operation of the National Pandemic Flu Service.  
• 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.
• Producing reliable estimates at present is very challenging with the move from GP consultations to the National Pandemic Flu Service. HPA modelling gives an estimate of 30,000 new cases in England last week (range 15,000 to 85,000). 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 (H1N1v) 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 31 (ending 02 August) GP consultation rates for flu-like illness in England decreased compared to the previous week (138 per 100,000 to 42 per 100,000). The rate declined in all three RCGP regions (North 36.1 per 100,000, Central 49 per 100,000 and South 39.2 per 100,000) and Central) and 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 dramatically from 225.7 per 100,000 to 72.2 per 100,000 in week 31. The daily rate for flu-like illness for the last few days remained low. These decreases coincide with the school holidays commencing on July 18 and the introduction of NPFS on July 23.

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 (09/06 to 04/08) all ages 

Figure 4: QSurveillance influenza-like illness rate by age band in week 31 (ending 02 August)

The latest rates were reduced in all age groups. This coincided with the introduction of the National Pandemic Flu Service and school closures. The highest flu-like illness consultation rates were in the <1 group="group" (who="(who" are="are" not="not" considered="considered" by="by" the="the" National="National" Pandemic="Pandemic" Flu="Flu" Service="Service" always="always" referred="referred" to="to" a="a" GP)="GP)" and="and" 1-4="1-4" year="year" age="age" groups.</p="groups.</p" />

SYNDROMIC SURVEILLANCE

NHS Direct
On 23 July the National Pandemic Flu Service (NPFS) was implemented. This had an impact on the number of 'cold/flu' calls received through the routine NHS Direct service so interpretation of these data is uncertain. The proportion of total estimated cold/ flu calls is currently 6.7%

Figure 5: Daily NHS Direct/HPA Syndromic Surveillance System estimated total cold/flu calls 2009 compared to routine daily NHS Direct 'cold/flu' calls 2008-2009 shown as a percentage of all NHS Direct calls

VIRAL CHARACTERISTICS

Viral characteristics (including antiviral susceptibility (as at 05/08/09): Testing for antiviral susceptibility is carried out by the Agency's Respiratory Virus Unit, Centre for Infections, in Colindale. 607 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, 110 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: 530 patients (hospitalised as of 8am on 05 August)

Deaths - the number of deaths related to swine flu in England is 36. (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

Total of Confirmed Cases reported by European Centre for Disease Prevention and Control (ECDC) (Update 17:00 CEST 04 August 2009)

Grand total of cases confirmed: 193,574
Total of deaths reported: 1,362

Table 1: Countries with more than 1000 laboratory-confirmed cases reported, as at 04 August (in addition to UK).

Country	Cases	% increase in last 7 days	Cumulative deaths
				Canada*	10449		59
China (Hong Kong)	4504	46%	3
China (mainland)	2152	16%	0
Germany	7177	114%	0
Israel	1719	13%	2
Japan*	5022		0
Malaysia	1460	20%	8
Mexico	16442	5%	146
Philippines	3207	20%	8
Singapore*	1217		6
South Korea	1520	19%	0
Spain*	1538		7
Taiwan*	1280		1
Thailand	8879	31%	65
USA**	43771		353
Southern Hemisphere
Argentina	4895	60%	243
Australia	23692	25%	70
Brazil	1958	25%	56
Chile	11860	2%	96
New Zealand	2872	6%	14
Peru	4781	45%	30

* No case update available since last week, although numbers of deaths are updated
**Cases in the US include both probable and confirmed cases. They also include confirmed cases from Puerto Rico, American Samoa, Guam and Virgin Islands.

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 6647
020 8327 7098
020 8327 7097
020 8327 6690

Weekly pandemic flu media update (PDF, 75 KB)

Last reviewed: 26 May 2010