N Hamlet, J Miller, H Gourlay, J Kerr and G Cunningham
N
Hamlet, Locum Consultant Public Health Medicine
J
Miller, CPHM (CDEH), Lanarkshire
NHS Board, 14 Beckford Street, Hamilton ML3 0TA
H
Gourlay, Healthcare Manager, Scottish
Prison Service, Calton House, 5 Redheughs Rigg, Edinburgh EH12 9HW
J
Kerr, Senior Nurse Advisor, Communicable Disease Control, Lanarkshire
NHS Board, 14 Beckford Street, Hamilton ML3 0TA
G
Cunningham, Food Safety Manager, Planning and Environment Department, North
Lanarkshire Council, Council Offices, 303 Brandon Street, Motherwell
Address for correspondence: Dr Neil Hamlet, Forth Valley NHS Board, 33 Spittal Street, Stirling FK8 1DX Neil.hamlet@fvhb.scot.nhs.uk
SMJ 2006 51(3): 50
Following
notification of a stool sample positive for Salmonella from an inmate of a
maximum security prison a concerted multidisciplinary public health response was
undertaken. Lanarkshire NHS Board Health Protection Team (HPT) held one Problem
Assessment Group Meeting and two Outbreak Control Team Meetings. The outbreak
period spanned three weeks during which there were three confirmed and six
probable cases of Salmonella enteritidis PT4 in prison inmates. The source was
not identified despite thorough investigation, however the outbreak control team
(OCT) was able to identify key recommendations around general hygiene, shared
toilet facilities and storage of cooked food in cells. The outbreak stimulated
closer working arrangements between the prison medical services and the local
HPT. Co-operation during the outbreak investigation and subsequent to the OCT
report facilitated both operational changes at the prison and improvements to
the management of infection control across the Scottish Prison Service.
The prison environment poses unique issues in relation to the potential for control or transmission of gastrointestinal pathogens. Her Majesty’s Prison (HMP) Shotts is a maximum security long term male adult prison catering for convicted prisoners serving sentences of four years to life. The prison has single cell accommodation with integral sanitation or access to night sanitation facilities. The prison population comprised around 530 inmates and 400 staff (150-200 per shift) at the time of the outbreak. The influx of new inmates and release of those having served their sentence is around 5-10 per week. The inmates stay in four halls (A-D), a National Induction Centre (NIC) and the Shotts Unit. Inmates only mix outwith the hall setting in the multifaith centre, library, gym, work areas and to a lesser extent when seeing visitors in the visitors’ hall. Generally staff are allocated to one area of the prison with limited cross-cover to other areas.
The
reporting of diarrhoea as a symptom is common in the prison. Prisoners are
routinely kept off work for a minimum of a half-day during which time they are
asked to submit a stool sample. If no sample is provided, as is the case in most
instances, and the prisoner appears clinically well they are returned to work
that afternoon.
Lanarkshire
NHS Board Health Protection Team (HPT) had never previously been called upon to
investigate a gastrointestinal outbreak in HMP Shotts.
According
to the Scottish Prison Service (SPS) there had been no reported gastrointestinal
outbreaks in Scottish prisons in the previous five years.
(Dr Alan Mitchell, Head of Heath Care, SPC; personal communication, 17/10/02)
Salmonella
are bacteria that cause infections of the bowel. The incubation period for
Salmonella is usually 12-36 hours but can range from 6-72 hours. Symptoms
include nausea, vomiting, abdominal pain and fever followed by diarrhoea which
usually settles in a few days.
The
index case was a young prisoner of Hall B, who had been admitted to the prison
in late 2001. He developed nausea, vomiting, non-bloody diarrhoea and abdominal
pain on 15th August 2002. A stool sample was reported as a
‘presumptive salmonella’ to the HPT eight days later. Other than a weekly
visit from his partner and child who had previously reported similar symptoms he
had no contact with the outside community. His duties in the prison were those
of a ‘passman’ and included cleaning the corridor and communal toilets in
Hall B. His duties did not include serving or delivering food to other
prisoners. Records revealed a negative stool sample in June 2002.
Epidemiology
Confirmed
cases were defined as those persons connected with the prison who were ill from
14/8/02 with symptoms of diarrhoea, vomiting and fever and who were reported
microbiologically positive for salmonella. Probable cases were as per 'confirmed
cases' but with no salmonella positive microbiology. Possible cases were not
defined due to the unusual situation relating to the ‘material advantage’ of
prisoners reporting diarrhoea in order to gain time off work to rest in their
cells. This situation would have significantly artificially inflated ‘possible
case’ numbers. Outbreak cases
were either ‘confirmed’ or ‘probable’ cases.
Enhanced
surveillance/case finding:
Notices
posted around the prison requested staff and prisoners to report to the Prison
Health Centre with any sickness or diarrhoeal illness. Stool samples were sought
from all prisoners who had recently reported to the Prison Health Centre with
diarrhoeal symptoms. Attempts were made to trace a prisoner who had been
released the previous day but had been unwell for three days prior to departure.
Stool samples and details of illness were sought from the child of the index
case. All newly self reported cases had stool samples taken promptly.
Analytical
epidemiology was not considered appropriate due to the small number of cases.
Environmental
investigations
North
Lanarkshire Council (NLC) Health Protection Service undertook a comprehensive
environmental assessment, including environmental sampling of all food
preparation areas including main kitchen, WRVS canteen, hall food trolleys and
microwaves. A full assessment was made of communal toilet and handwashing areas
and the council food safety service and HMP Shotts jointly assessed the physical
state of cooking facilities in Hall areas and sought evidence of hoarding of
foodstuffs in prisoner's cells.
Microbiology
Positive
isolates from clinical samples were forwarded to the Scottish Salmonella
Reference Laboratory. Environmental samples taken from food preparation and
delivery areas were analysed at Glasgow Scientific Services Laboratory.
Epidemiology
A
total of nine outbreak cases were identified. Three prisoners were defined as
confirmed cases. Two had duties as passmen which involved cleaning communal
toilets. Each was located in a different Hall. Six prisoners were classified as
probable cases and were located across the four Halls and the NID.
Despite repeated interviews no clear links could be identified between
the six probable cases or the three confirmed cases. The outbreak curve
generated suggested ongoing spread rather than a point source [Figure
1].
Environmental
Food
preparation and delivery:
The only point of concern raised from an initial kitchen risk assessment was the use of pooling whole eggs for the preparation of scrambled eggs. Nineteen samples taken from food preparation and delivery areas including the prison kitchen, WRVS canteen, hall serveries and hall microwaves were reported negative.
Communal
Toilet Areas Assessment:
Assessment
of toilet and hand washing areas in work sheds revealed significant deficiencies
in infection control practices. In the work sheds toilet areas were dirty and
rubbish was lying around. Washbasins were extremely dirty, some with stagnant
water and rubbish such as paper, tea-bags and tissues in the sinks.
Bar soap when available appeared mostly wet and soggy. Electric hand dryers were available in all toilets while in
others dirty and wet terry towels were in use. Some toilet bowls were found in a
state of disrepair while the majority were very dirty with scum and faecal
smearing seen. No toilet tissue was noted in any of the toilets since paper is
issued only on request. The toilet and hand washing facilities in the other
communal areas examined (education centre, visitor’s room, gym and hall C)
were noted to be very good.
Food
in cells:
Prisoners
frequently stored cooked prison food in their cells for later consumption or
bartering purposes. A significant amount of food was found in cells. Hygiene
standards varied greatly between individual cells but in up to 50% of cells
hygiene was a matter of concern.
Microbiological
A
total of 13 samples were examined from the prison community plus the daughter of
the index case over the period 21/8/02 to 10/9/02. Three positive stool samples
were obtained. All three were later identified as Salmonella enterididis Phage
Type 4.
The
index case had a history of contact with a symptomatic daughter during weekly
visits. Stool samples from the child were negative.
Control
Measures
Care
of cases
One
case was admitted to the local NHS Infectious Diseases Unit for one week.
Twenty-seven prisoners were placed in their cells during working hours while
awaiting stool samples or clinical improvement. Only four prisoners were placed
in isolation for periods in excess of one full day, the range being 3- 6 days.
Isolation
To
prevent primary and secondary spread the advice of the OCT was that cases should
be kept off work duties until 48 hours symptom free. This was managed in the
prison setting by ensuring that all confirmed and probable cases were confined
to their cells and assessed daily by prison nursing staff. This procedure went
further than the OCT advice but ensured symptomatic cases did not attend work or
have recreational time with other prisoners in their own hall.
Information
Posted
notices informed staff and prisoners regarding infection control and good
hygiene.
Improved
hygiene
Regarding
communal toilet and handwashing facilities the OCT advised:
·
A ‘deep clean’ be carried out of all communal toilet areas, and then
kept clean.
·
Use of liquid soap in wall mounted dispensers.
·
Paper towels be made available and disposed of in foot-operated, lidded
bins.
·
In those areas assessed to be a ‘fire risk’ adequately maintained
warm air dryers could be used.
·
Plugs be removed from the communal area washhand basins.
·
Passmen
be issued with protective clothing for toilet cleaning duties.
Although
environmental health inspection of kitchens gave little objective cause for
concern a precautionary ‘deep clean’ of the kitchen was recommended.
Steps
to improve food hygiene
In
response to the concerns raised surrounding the storage of food within cells and
a subsequent risk assessment exercise the following recommendations were made:
·
Refurbishment of one Hall servery as a pilot project with planned further
upgrading of other servery areas subject to available resources.
·
Named staff to be given responsibility for monitoring cleanliness in each
accommodation area.
·
Food safety advice to be displayed on notice boards, menus, and in every
cell.
·
General hygiene advice to be incorporated in SPS video link service.
·
Facilities made available to encourage the dispose of waste food by
prisoners.
National
implications
The
OCT made recommendations to the SPS in its entirety as well as formulating local
recommendations to the Shotts prison.
The
reporting of gastrointestinal outbreaks in Scottish prisons is not a common
occurrence. This was the first such incident reported to the Scottish Centre for
Infection & Environmental Health (SCIEH)[i]
since a robust surveillance system was introduced across Scotland in 1996. (John
Cowden, Epidemiologist, SCIEH, personal communication, 25/9/02).
In England and Wales the then Public Health Laboratory Service (PHLS)[ii] monitored gastrointestinal outbreaks in prisons, young offenders institutions and secure units. There had been 16 outbreaks between 1992 and 2001 and one outbreak in 2002. Salmonella enteriditis PT4 had been the causative organism in seven outbreaks. Numbers affected were between two and 200 (Surveillance Co-ordinator, Gastrointestinal Disease Division, PHLS, personal communication, 16/10/02).
[i] SCIEH is now Health Protection Scotland (HPS)
[ii] PHLS is now part of Health Protection Agency (HPA)
This outbreak was small in nature, but due to the unique community nature of the prison setting it was appropriate to activate a full investigative and control response at an early stage. Despite this the cause of the outbreak was not ascertained.
In this setting NHS and environmental health staff were reliant on advice regarding the application and adaptation of control measures to the security environment and the sometimes adversarial, often mistrusting, culture of prison life. A clear example of this was that the OCT did not accept self-reporting of symptoms without a degree of healthcare ‘approval’. The hoarding of cooked food by prisoners in cells is not in itself a contravention of prison rules and therefore influencing such practices was difficult. Yet it was considered that a high proportion of cells were a hygiene risk due to food storage.
The levels of toilet cleanliness, provision of toilet paper and appropriate hand-washing and hand-drying facilities particularly in work sheds was clearly inadequate. Parallels can be drawn with research findings from standards in school toilets where hygiene standards are found to be poor and the facilities poorly maintained. 1 The application of evidence based infection control practices such as the provision of single use paper towels for hand drying were practically difficult in this setting given perceived risks of fire hazards and blockage of basins and toilets.
Recognising the unusual nature of this outbreak and the learning which had taken place by all involved, the OCT made a number of local and national recommendations to the NHS Board and the Scottish Prison Service.
It was considered there was a need to increase the proactive interaction between SPS institutions and both Local Authority Health Protection Departments and NHS Board Public Health Departments in regard to food safety and infection control practices.
Despite
recognised practical difficulties, the SPS was reminded that it must provide
acceptable standards of hygiene particularly in relation to toilet and washing
facilities.
The storage of cooked food in individual cells was felt to be potentially hazardous. The SPS was asked to assess its ‘duty of care’ in this regard and consider advice to inmates and ensure the easy and hygienic disposal of cooked food from cells.
The
OCT welcomed the SPS Infection Control Manual 2 but to improve staff and inmates
safety asked that the SPS should ensure that due consideration be given to
adequate resources.
POSTIVE
OUTCOMES
This was a relatively small outbreak, but one which by combination of setting and timing has had significant positive benefits at national level.
Recent national guidance recommended that NHS Boards be responsible for following up on the outcome of OCT recommendations 3 By doing precisely this and with good co-operation by Shotts Prison, environmental hygiene and food hygiene showed demonstrable improvement. For example, liquid soap and paper towels were made available in all communal toilet areas, the cleaning frequency within those areas was increased and passmen were issued with protective clothing. The usual practice of serving food to other prisoners, by passmen with toilet cleaning duties, was ceased. All servery areas were upgraded and the prison established a monthly Infection Control Group.
Of
perhaps more significance, formal follow up on the OCT recommendations to the
SPS was influential at a national level in assisting the SPS to progress the
development of an infection control structure across the service, with a planned
programme of work and regular reporting. This built upon the SPS infection
control guidelines also published in late 2002.
A full time infection control adviser was promptly seconded to SPS
headquarters, appropriate training started, and the first national SPS infection
control committee was established within six months of the OCT report. This
committee has successfully increased the profile of infection control across the
SPS, with prison based infection control groups established in several prisons
across Scotland. Indeed the SPS has now corporately embedded infection control
as part of their civilising agenda. Members of the Lanarkshire HPT continue to
provide NHS input to the national SPS infection control committee building on
the links started during the outbreak.
ACKNOWLEDGEMENTS
This
publication acknowledges the full involvement of the members of the OCT.
REFERENCES
Barnes PM, Maddocks A. Standards in school toilets – a questionnaire survey. J Public Health, 2002; 24:85-87
SPS
Control of Infection Guidelines, Sept 2002, Scottish Prison Service,
Edinburgh
Managing
incidents presenting actual or potential risks to the public health.
Guidance on the roles and responsibilities of incident control teams. 2003,
Scottish Executive, Edinburgh