England: 6,000 new clinical cases in week 51

[Celvin11]

England: HPA estimates around 6,000 new cases in week 51

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 6,000 (range 3,000 ? 13,000) new clinical cases in England in week 51. The estimated number of new cases has decreased in all regions and age groups.

http://www.hpa.org.uk/web/HPAwebFile/HPAweb_C/1259152416075

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

Cumulative numbers

Period 24 Aug 2009 - 20 Dec 2009 (covering four months)

HPA estimations return 506,500 clinical H1N1 cases in England this autumn, corresponding to 1 % of population
(range 254,500 - 1,094,500)

Week 35 : 4,500 (range 2,500 - 10,000) reported 3 Sep
Week 36 : 3,000 (range 1,500 - 6,500) reported 10 Sep
Week 37 : 5,000 (range 3,000 - 11,000) reported 17 Sep
Week 38 : 9,000 (range 5,000 - 20,000) reported 24 Sep
Week 39 : 14,000 (range 7,000 - 30,000) reported 1 Oct
Week 40 : 18,000 (range 9,000 - 38,000) reported 8 Oct
Week 41 : 27,000 (range 13,000 - 58,000) reported 15 Oct
Week 42 : 53,000 (range 27,000 - 115,000) reported 22 Oct
Week 43 : 78,000 (range 39,000 - 169,000) reported 29 Oct
Week 44 : 84,000 (range 42,000 - 181,000) reported 5 Nov
Week 45 : 64,000 (range 32,000 - 140,000) reported 12 Nov
Week 46 : 53,000 (range 26,000 - 114,000) reported 19 Nov
Week 47 : 46,000 (range 23,000 - 99,000) reported 26 Nov
Week 48 : 22,000 (range 11,000 - 47,000) reported 3 Dec
Week 49 : 11,000 (range 6,000 - 24,000) reported 10 Dec
Week 50 : 9,000 (range 4,500 - 19,000) reported 17 Dec
Week 51 : 6,000 (range 3,000 - 13,000) reported 24 Dec
Total : 506,500 (range 254,500 - 1,094,500)

Weekly epidemiological updates archive
http://www.hpa.org.uk/webw/HPAweb&HPAwebStandard/HPAweb_C/1244442494458?p=1259151876580

Mid-year 2008 pop of England stood at 51,446,200

HPA estimates a number corresponding to 1 % of England's population among clinical swine flu cases this autumn

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

First wave

Estimates of the numbers of clinical infections

It is estimated that by 27 September, the cumulative number of people in England with symptomatic illness was between 144,000 and 670,000 people, with a mid-estimate of 320,000

http://www.hpa.org.uk/web/HPAwebFile/HPAweb_C/1258560552857 (p. 14)

By age group (extracted from table p. 8):
< 1 y 0.6 %
1-4 y 0.7 %
5-14 y 1.8 %
15-24 y 1.4 %
25-44 y 0.5 %
45-64 y 0.2 %
65+ y less than 0.05 %
Total all ages 0.66

During the first wave of pandemic (H1N1) in England it is estimated that 0.66% of the population fell ill (p. 16)

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

BMJ:

Mortality from pandemic A/H1N1 2009 influenza in England: public health surveillance study

Liam J Donaldson, chief medical officer for England (and others)

Published 10 Dec 2009 http://www.bmj.com/cgi/content/full/339/dec10_1/b5213

By 8 November, about 1% of England?s population had had symptomatic pandemic A/H1N1 2009 infection (estimated range 0.5-2.2%). We estimate that 0.026% (range 0.011-0.066%) of these individuals died from causes related to this infection. Most (64%) of those who died had severe or incapacitating underlying disease. The risk of contracting and dying from pandemic A/H1N1 was nine times greater for people in one of the high risk groups currently being offered vaccination than for the rest of the population. A considerable minority of those who died, however, were largely healthy.

The first influenza pandemic of the 21st century is considerably less lethal than was feared in advance.

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

From BBC Fergus Walsh on Flu 17 Dec 2009

 

[SusanC]

Re: England: 6,000 new clinical cases in week 51

Celvin, do you have a link to the source for Walsh's figures? Thanks!!

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

@SusanC

BBC Fergus Walsh on Flu
http://www.bbc.co.uk/blogs/thereporters/ferguswalsh/

Source for number of cases in first and second waves is obvious HPA reports

There will be some minor discrepancies in numbers, depending on from when you start counting 2nd wave.

HPA report suggests first wave ended 27 Sep. Fergus Walsh in his diagram a few weeks earlier

Hospitalisations: I reckon, (but not 100% sure) source is also the weekly epidemiological updates. Likely, he went through all of them adding numbers

 

[SusanC]

Re: England: 6,000 new clinical cases in week 51

Also, from Donaldson's paper, overall CFR 26 per 100,000 cases, or 0.026%, distributed as follows:

age vs Case fatality rate deaths per 100 000 cases (range):
<1 : 30 (2-260)
1-4 : 27 (3-120)
5-14 : 11 (3-36)
15-24 : 12 (3-40)
25-44 : 30 (10-88)
45-64 : 65 (21-200)
65 or over : 980 (300-3200)

The UK is now vaccinating healthy kids aged 6 months to 5 years (with the adjuvanted vaccine). In an article in Pulse, Donaldson says it's time to vaccinate the general population because some of those who died were previously healthy. However, the published data from his own paper (link in Celvin's post) shows that among children aged 5 or below, ALL those who died had either incapacitating or severe systemic illness, and NONE had mild systemic illness or were previously healthy.

Based on the above, I think it's time they change their vaccination strategy, and focus on older adults and stop pushing the vaccine on young kids.

 

[SusanC]

Re: England: 6,000 new clinical cases in week 51

@SusanC

BBC Fergus Walsh on Flu
http://www.bbc.co.uk/blogs/thereporters/ferguswalsh/

Source for number of cases in first and second waves is obvious HPA reports

There will be some minor discrepancies in numbers, depending on from when you start counting 2nd wave.

HPA report suggests first wave ended 27 Sep. Fergus Walsh in his diagram a few weeks earlier

Hospitalisations: I reckon, (but not 100% sure) source is also the weekly epidemiological updates. Likely, he went through all of them adding numbers

Thanks!!

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

Also, from Donaldson's paper, overall CFR 26 per 100,000 cases, or 0.026%, distributed as follows:

age vs Case fatality rate deaths per 100 000 cases (range):
<1 : 30 (2-260)
1-4 : 27 (3-120)
5-14 : 11 (3-36)
15-24 : 12 (3-40)
25-44 : 30 (10-88)
45-64 : 65 (21-200)
65 or over : 980 (300-3200)

The UK is now vaccinating healthy kids aged 6 months to 5 years (with the adjuvanted vaccine). In an article in Pulse, Donaldson says it's time to vaccinate the general population because some of those who died were previously healthy. However, the published data from his own paper (link in Celvin's post) shows that among children aged 5 or below, ALL those who died had either incapacitating or severe systemic illness, and NONE had mild systemic illness or were previously healthy.

Based on the above, I think it's time they change their vaccination strategy, and focus on older adults and stop pushing the vaccine on young kids.

Good point!

Thanks for adding CFR by age group to the thread, and for highlightng the realitively high CFR among middle-aged and, especially among elderly

 

[Celvin11]

Re: England: 6,000 new clinical cases in week 51

Total number of incidents of A/H1N1 infections in England surely is several millions (I have been searching on internet for more details, but England is very much concentrating on clinical cases)

Just for the exercise of the mind: if the '8% symptomatic, but 39% seropositive' formula was valid for the entire population, understood as almost four times more people being seropositive than those being symptomatic*, we would see a picture of 750,000-800,000 falling ill (as described by HPA) - and another 2.908 - 3.102 million seropositive not falling ill - total number of infected between 3.658 and 3.902 million (7.1 - 7.6 % of England's population). Maybe not too far off. (All those symptomatic were of course also seropositive, representing around 20.5 per cent of all seropositive)

I will try to look further for some reliable estimates on total number of infections.

France reported a total of 1.98 m infected on 19 November
http://news.xinhuanet.com/english/2009-11/19/content_12488417.htm

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*and, hence, not indicating 8% of total pop being symptomatic, 39% seropositive (added for clarification)