| Chapter 2 The
Central Scotland and Tayside Outbreaks and Their
Implications |
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| The
Central Scotland Outbreak |
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| 2.1 Perhaps
somewhat against hope and expectations, it is not our
intention to describe or debate in any detail in this
report the likely cause of the Central Scotland outbreak
or the individual roles and actions of those involved in
its occurrence, management and control. That is for the
FAI and any criminal proceedings and, as indicated
earlier, commentary on these issues could delay
publication of this report. The findings of the FAI will
be published in due course and there may be further
issues identified and recommendations arising out of that
process to add to those in this report. We also
recommend, later in this document, that a full scientific
report of the Central Scotland outbreak should be written
up and published in due course. |
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| 2.2
Therefore, the aim of this chapter is to set out very
briefly the course and scale of the outbreak and some of
the key facts, statistics and issues associated with it -
to help set the context for the response measures we
propose and which are set out later in this report. |
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| Background |
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| 2.3 The
possibility of an outbreak of food poisoning caused by
infection with E.coli O157 was identified on the
afternoon of Friday, 22 November 1996 when the Public
Health Department of Lanarkshire Health Board ('the
Health Board') became aware of several cases of
infecXtion (some of which had been confirmed by
microbiological testing) in residents of Wishaw in the
central belt of Scotland. |
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| 2.4 The
Health Board informed the Environmental Services
Department of North Lanarkshire Council ('the Council')
that day, 22 November, and arrangements were subsequently
put in place to investigate and control the outbreak in
accordance with the updated guidelines issued in 1996 by
The Scottish Office Department of Health Advisory Group
on Infection4. An outbreak control team (OCT) was formed
on Saturday, 23 November. |
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| The
Source of the Outbreak |
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| 2.5 By the
evening of 22 November 1996, histories had been obtained
from 9 of the 15 confirmed or suspected cases.
Indications are that 8 of these 9 had consumed food
obtained, either directly or at a church lunch, from J
Barr and Son, Butchers, of Wishaw. The possibility of
other common exposures could not at this stage be
excluded, as a high proportion of the population of
Wishaw might patronise Barr's in any one week. Although
outwardly a small, local butcher with adjacent bakery
shop, the business was involved at the time of the
outbreak in a substantial wholesale and retail trade
involving the production and distribution of raw and
cooked meats and bakery products from the Wishaw
premises. It employed some 40 people, many on a part-time
basis. |
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| 2.6 The
Group was told that Mr Barr was visited by
representatives of the Health Board and the Council late
on Friday 22 November. The circumstances of that meeting
are relevant to a current criminal charge against Mr Barr
and it would be inappropriate to comment further at this
time. The voluntary closure of the entire business
(including the bakery) was announced on Wednesday, 27
November 1996. |
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| 2.7 The
distribution chain of meat and meat products from Barr's
was diverse and complex and it took some days for the
details on that to be unravelled from a painstaking
investigation of the company's records. That caused
delays in relation to the identification, publicly, of
some of the outlets involved or potentially involved in
the outbreak. Some 85 outlets throughout the central belt
of Scotland were eventually identified as being supplied
by the company, making the task of outbreak management
and control extremely difficult. |
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| 2.8 Large
quantities of meat and meat products were taken from
Barr's, or from other premises supplied by Barr's, for
microbiological testing. These included cold cooked meats
supplied to other butchers and the remains of gravy
supplied with cooked steak to the Wishaw Parish Church
lunch on 17 November. Microbiological swabbing of Barr's
premises was undertaken and some items of equipment sent
for detailed examination. The large numbers of food
samples have placed a heavy burden on the testing
laboratories and testing is still on-going. The staff of
Barr's were subsequently screened. It would not be
appropriate to go into the results of testing while
criminal proceedings are pending. |
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| 2.9 It is
understood that Barr's had claimed exemption from the
Meat Products (Hygiene) Regulations 1994 ('the 1994
Regulations') so as to be subject only to the Food Safety
(General Food Hygiene) Regulations 1995 ('the 1995
Regulations') - see Chapter 7 of this report. We
understand that the Procurator Fiscal's enquiries include
the question of possible contravention of the 1994
Regulations in respect of alleged handling of meat
products for sale other than to the final consumer when
the premises were not approved under these regulations.
It would not therefore be appropriate to comment further
on that matter. |
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| 2.10 Members
of the Group visited Barr's premises during the course of
our investigations, in order to familiarise themselves
with the physical layout and to gain a first hand
impression of the circumstances and nature of the
operation of the business. The premises comprise 2 retail
units - a butcher's and a baker's. At the rear of the
butcher's retail premises is the manufacturing area. The
premises are long established and have been extensively
converted and extended. However, the premises are similar
to many other premises of this age. The layout and design
constrain the measures that can be taken to ensure
effective product flows and separation of cooked and raw
products. However a significant capital investment had
been made in the premises, which have modern chillers,
equipment and work surfaces. |
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| Management
and Control of the Outbreak |
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| 2.11 The OCT
first convened on Saturday, 23 November and met initially
daily (less frequently later on as it became clear that
the outbreak was being brought under control). It was
chaired by Dr Syed Ahmed, Consultant in Public Health
Medicine (Communicable Diseases/Environmental Health) of
Lanarkshire Health Board and included representatives of
the Health Board, North Lanarkshire Council, local
hospital and healthcare NHS Trusts, the Scottish Centre
for Infection and Environmental Health (SCIEH) and the
Wishaw Health Centre. |
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| 2.12
Representatives of The Scottish Office Department of
Health (SODoH) and Agriculture, Environment and Fisheries
Department (SOAEFD) met with the Health Board and the
Council on the evening of Tuesday, 26 November and a Food
Hazard Warning was issued by The Scottish Office on
Wednesday, 27 November. This provided details of the
outbreak and asked food authorities in the central belt
to investigate suspected outlets. Further advice and
guidance to butchers was issued by The Scottish Office by
means of a further Food Hazard Warning on 28 November
1996. The Scottish Office attended OCT meetings, as
observers, from Thursday, 28 November. |
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| 2.13 We
reviewed the minutes of OCT meetings and spoke to key
representatives of the Team. The OCT dealt during the
outbreak with the full range of matters envisaged in the
guidelines and some specific issues arose out of that. We
expect that the OCT's operation, individuals' roles and
related issues will be examined in the context of the
FAI, so it is not possible to comment in detail on these
issues in this report. However our interim report
recorded our view that the guidelines, and the
arrangements put in place locally for outbreak management
and control, apparently worked reasonably well in
practice - albeit that the nature and scale of the
outbreak presented a stern test and challenges to the
system. We have not substantively changed our view on
that. Some recommendations were made in our interim
report and some further commentary on outbreak management
and control is included in Chapter 12. |
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| 2.14
Regardless of the outcome of the FAI, recognition needs
to be given to the efforts of all those involved in the
identification, management and control of the outbreak
and in dealing with its effects. The enormous personal
efforts, the difficult professional judgements and
resource pressures involved have not always been
recognised in the face of understandable concern about
the outbreak. There has also been some explicit or
implied criticism of those involved. There are, no doubt,
lessons to be learned: but that should not detract from
what was achieved, in extremely difficult circumstances
and in the face of a rapidly evolving situation, by those
most closely involved. |
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| The
Course and Scale of the Outbreak |
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| 2.15 As the
epidemic curve for the outbreak indicates, the number of
cases of suspected or confirmed infection increased
dramatically from the outset of the outbreak. By Sunday,
24 November reports indicated that distribution of
products from Barr's had extended beyond the local
authority area into the central belt of Scotland. Cases
of infection were subsequently reported in Forth Valley,
Lothian and Greater Glasgow. In the early days of the
outbreak, before full exposure histories were obtained
and in the absence of comprehensive information about
supply and distribution, the OCT could not assume that
there was only one source of contaminated food. |
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| 2.16
Epidemiological and subsequent microbiological evidence
shows that the outbreak comprised of several separate but
related incidents - relating to the lunch (attended by
around 100 people) held in Wishaw Parish Church Hall, a
birthday party held in the Cascade Public House on 23
November 1996 and retail sales in Lanarkshire and Forth
Valley. All isolates of E.coli O157 from
individuals in the outbreak belonged to phage type 25 and possessed the verocytotoxin
gene VT2. To date, 262 of these isolates (which total
272) have been subjected to pulsed-field gel
electrophoresis (PFGE): all had indistinguishable
profiles. |
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| 2.17 As of
27 March 1997, the final date of onset of illness in a
confirmed case of illness associated with the outbreak is
15 December 1996. A possible case was, however, reported
with a date of onset of 29 December 1996. The outbreak
was declared over on Monday, 20 January 1997 - although
it was recognised that further cases could occur as a
result of secondary (person to person) spread, or could
be identified retrospectively as laboratory results
became available. It was also recognised that further
deaths could occur following prolonged illness. |
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| 2.18 After
the outbreak was declared over, microbiological and
serological results have continued to be accumulated and
clinical and exposure histories reviewed. The 27 March
figures are provisional but unlikely to change
significantly. They show 496 cases of infection with E.coli
O157 linked to the outbreak, of which 272 are
confirmed, 60 probable and 164 possible. It is the
largest ever outbreak of infection with the organism in
the UK. A further breakdown of these figures is as
follows:- |
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Note:
Confirmed case: someone with E.coli O157
identified in their stool, irrespective of clinical
history;
Probable case: someone with bloody diarrhoea and positive
serology;Possible case someone who has non-bloody
diarrhoea with positive serology or someone who
has no symptoms with positive serology or someone
who has bloody diarrhoea without positive serology. |
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| 2.19 The
outbreak placed substantial presures on local health
resources. In Lanarkshire, the Wishaw clinic carried out
batches of tests on some 969 people with diarrhoea (and
there will have been, in addition, a substantial number
of people who attended their GP). There were admitted to
hospital 127 people, of whom 13 required dialysis (all
transferred to Glasgow). Twenty seven people were
diagnosed as having evidence of thrombotic
micro-angiopathy (ie haemolytic uraemic syndrome or
thrombotic thrombocytopaenia purpura)6. |
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| 2.20 There
have been 18 deaths (all adults) associated with the
outbreak - the second highest number of deaths associated
with an outbreak of E.coli O157 infection in the
world. Of these, 8 people had attended the luncheon
served at Wishaw Old Parish Church on 17 November 1996
and 6 were residents of Bankview Nursing Home in
Bonnybridge, Forth Valley. The age range of the 12
residents of Lanarkshire who died was 69 to 90 years and
in Forth Valley it was 70 to 93 years. |
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| Issues
Arising |
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2.21 The
following chapter sets out some of what is (and is not)
known about E.coli O157, its characteristics and
behaviour. The Central Scotland outbreak has brought some
of that very sharply into focus and has caused us to
examine a number of general issues and questions. These
include:-
- how and why fresh
meat becomes contaminated with E.coli O157 in the
first place;
- the likely
distribution in the food chain;
- the measures that can
and should be taken to minimise
contamination/cross-contamination;
- how these measures
are regulated and enforced; and
- once an outbreak has
occurred, the steps that need to be taken to
manage and control it - and the adequacy of
systems and arrangements for that.
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| 2.22 The
potential for contamination/cross-contamination with the
organism, its virulence and the very severe effects it
can have on particularly vulnerable groups of the
community have been tragically underlined. Of particular
significance is the issue of asymptomatic excretion of
the organism, which may have very substantial
implications in terms of the potential for the spread of
infection and outbreak management and control. |
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| 2.23 All of
these issues, and more, have been taken into account by
the Group in the preparation of this report and our
recommendations. As previously noted, the full facts and
circumstances of the outbreak cannot be discussed because
of the limitations imposed by the judicial processes now
underway. Nonetheless, we believe that what we have
learned about the circumstances of the Central Scotland
outbreak, and the inevitable uncertainties that may
surround outbreaks generally, provide strong
justification for the precautionary, preventive measures
we propose and the recommendations we make. |
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| The
Tayside Outbreak |
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| 2.24 For
completeness, it should be recorded that, as requested by
the Secretary of State, we reviewed the circumstances of
the Tayside outbreak in preparing this report and
recommendations. |
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| 2.25 Six
people in a Tayside nursing home were identified as
showing symptoms of disease, 5 of whom fell ill on 31
January 1997 and the other on 9 February. Of the 6 cases,
5 have been confirmed as infected with E.coli
O157. There have been 3 deaths associated with the
outbreak. |
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| 2.26 All of
the circumstances of the Tayside outbreak point to the
likelihood of it being a point-source outbreak (ie an
outbreak associated with a single event or a single
place). In that sense, it raises no issues that do not
arise out of the Central Scotland outbreak. Nonetheless,
the fact that it occurred at all (along with other recent
outbreaks), and has had a grievous impact on a further
group of elderly, vulnerable people, has served to
reinforce the issues and concerns discussed throughout
this report. It also confirms the possibility of a high
level of asymptomatic carriage in humans and the
difficulties that may cause in outbreak investigations |
