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Norovirus: challenges of outbreak management in community hospitals

Agnes Crighton
BN SPQ RSCN RGN
Infection Control
Nurse
NHS Tayside, Dundee

Emma Burnett
MSc BN SPQ RGN
Lecturer and
Researcher in Infection Prevention and
Control, University of
Dundee

Norovirus outbreaks are a common occurrence in healthcare settings and can be problematic due to the rapid spread of the virus and the vulnerability of patients, particularly in the community. This article identifies some of the key challenges involved in containing and managing such outbreaks effectively

Norovirus, previously known as Norwalk, was first recognised in 1968. It is an extremely infectious, small round structured virus and is commonly acquired from an infected person via the faecal-oral route, or by aerosol spread, particularly when a patient vomits.1 A small infectious dose of 10-100 organisms is all that is required, making spread difficult to control.2

Outbreaks in community hospitals often begin with an infected patient or staff member coming into the hospital from the community setting and the virus being transmitted directly from person to person.3 Within this setting, the transmission predominantly occurs through ingestion via the faecal-oral route. Laboratory diagnosis of norovirus is determined by virology testing of faeces using reverse-transcription polymerase chain reaction (RT-PCR), which has the ability to detect low levels of the virus.

To enable the most reliable laboratory results, faecal
specimens should be obtained within 48-72 hours after the onset of clinical symptoms.4 There is no current treatment or vaccination for the virus. Symptomatic therapy would consist of replacing fluid loss from vomiting and diarrhoea, and correcting electrolyte imbalances through oral or intravenous fluid administration. This would be especially important for the young and the elderly population.

Clinical presentation of norovirus infection

  • Incubation period: 24-72 hours (although cases have been known to occur within 12 hours of exposure).
  • High attack rates: average 45%.
  • Acute gastroenteritis with predominant vomiting, nausea, abdominal cramps, diarrhoea ("stomach flu"), low-grade fever.
  • Dehydration.
  • Duration of clinical symptoms: 12-72 hours.5

Challenges in community hospitals
The distance between community hospitals and regional centres can present several challenges during an outbreak. Specimen collection times and transportation to laboratory is often sporadic, so regular collections can be difficult to achieve during an outbreak. Healthcare workers should communicate with the infection prevention and control team, and need to be aware of systems in place in their area, which allows them to have specimens transported quickly to the laboratory. In some areas this may include using a pre-arranged taxi service.

Out-of-hours services can also vary and may result in reduced or no medical cover during these times. Furthermore, reduced domestic and support services may also provide further challenges. Additional environmental cleaning is essential during an outbreak, therefore healthcare workers and the infection prevention and control team will have to liaise with domestic services in order to provide an increased,
effective service.

Isolation of patients is a fundamental measure in preventing the transmission of norovirus to patients and healthcare workers. Many community hospitals are often situated in older buildings, which can have inadequate or no isolation facilities. Indeed, many also still have the layout of old Nightingale wards, which makes isolation or separation of infected patients even more problematic. If isolation is unachievable either due to lack of facilities or increased numbers of infected patients, then cohorting symptomatic patients in the same area, nursed by the same members of staff, can also assist in reducing the spread of the virus.6 However, this in itself can present problems as it is often difficult to achieve if there are no separate areas from the main ward available.

Support from the infection prevention and control team is essential during outbreaks in community hospitals. However, regular physical contact can be challenging due to the locations of some community hospitals. Most infection prevention and control teams have responsibility for a wide geographical area and are often located in a central hospital; so are generally not on site. Therefore, the team will need to consider time and distance from their place of work so that they are able to visit on a regular basis during the outbreak. Communication by phone offers advice and support but regular visiting is essential for an accurate and well executed planning process through the outbreak.

Management
The first essential step to be taken by ward staff is the immediate reporting of any patient with sudden or unexplained vomiting or diarrhoea to the infection prevention and control team, in addition to the immediate isolation or cohorting of affected patients. Subsequent infected patients should also be isolated and cohort nursed as required, considering the facilities available.

Contact precautions, in addition to standard infection control precautions should be adopted immediately. Stool specimens should be obtained for microbiology, virology and Clostridium difficile toxin testing within the first 24 hours. This will allow for rapid action to be taken in an attempt to prevent further spread.

Effective hand hygiene is the single most important measure to prevent the spread of infection.7 This not only includes healthcare workers, but also patients.8 Sadly, hand hygiene compliance can be more difficult in older facilities, as many do not have the recommended number of sinks to patients ratio.

The handwash sinks can also be inappropriately positioned in ward areas, especially in the Nightingale-type wards and many still do not have elbow- or wrist-operated taps. Alcohol-based hand gels should not be used for hand hygiene purposes during any diarrhoea-related outbreak, and this must be made explicit to all relevant healthcare staff. The appropriate use of personal protective equipment, such as disposable aprons and gloves, is also an essential part of precautionary measures; therefore, staff must ensure there are adequate supplies to enable extra use.

Effective decontamination with hypochlorite solution is essential to reduce the microbial load on surfaces and equipment. Local policies and guidance should be adhered to at all times and further advice sought from the infection prevention and control team if required. Many old buildings still in use have not been renovated to modern standards, which can mean multiple ridges, uneven surfaces and unsealed walls and floors, making decontamination even more problematic.

Estates personnel may need to be brought in to assess the condition of the environment and undertake any work required.
Staff from the affected ward should not work in other clinical areas during the outbreak to prevent further spread. It is also vital to restrict staff coming in from other ward areas, including use of bank nurses and agency staff. Healthcare workers from other departments also require relevant information concerning the outbreak to allow them to cancel and rearrange non-essential care until the ward reopens.

Symptomatic patients should not visit other departments to prevent transmission of the virus into another area. If treatment or investigations are essential to a patient's care, staff must liaise with each other to minimise the risk of transmission by taking the patient last on the list and performing decontamination of the area as per guidelines. Furthermore, it may also be necessary to restrict relatives and visitors to the ward, depending on the severity of the outbreak.

As in regional centres, ward closures impact on admissions, discharges and transfers within the system. Patients involved or affected by the outbreak:

  • Cannot be transferred from one healthcare facility to another when they are symptomatic.
  • Have to be symptom-free for 48 hours before transfer is possible within healthcare settings.
  • Can be discharged to their own homes if they
  • are asymptomatic.

Constant surveillance by the infection prevention and control teams and adherence to the current outbreak pack policy should be undertaken. Accurate written documentation between ward staff and the infection prevention and control team is essential. Daily email communication is used by some health boards to inform all relevant disciplines of changes during the outbreak. However, this method can also cause problems if emails are not accessed regularly. Outbreak meetings involving all relevant disciplines are required throughout the duration of the outbreak. This includes the communications team responsible for dealing with the media.

Education
It is imperative that all healthcare workers have the appropriate infection prevention and control knowledge and skills to effectively respond to the challenges of a norovirus outbreak. They should attend regular educational sessions provided by the infection prevention and control team. Senior charge nurses and managers of individual departments can arrange extra education with the team if this is deemed appropriate.

During an outbreak such as this, the infection prevention and control team would usually provide additional education to staff involved. Difficulties can arise in staff attendance to arranged updates due to staff shortages, distances from venue and lack of motivation. Attendance at these sessions is important as they provide guidance, support and advice.

Conclusion
It is estimated that norovirus affects between 600,000 and one million people in the UK every year. Vulnerable patients such as the elderly are at particular risk of this infection, which can result in a number of devastating symptoms. Outbreaks in community hospitals are particularly problematic as the virus spreads very easily from person to person and can continue for long periods of time and the population are usually elderly.

As a result of this, the management of norovirus within community hospitals presents significant challenges to the organisation, healthcare workers and the infection prevention and control team. High-quality infection prevention and control measures, especially hand hygiene, robust organisation structure and effective communication are some of the most important aspects to consider when dealing with such
an outbreak.

References
1. Health Protection Scotland (HPS). Gastro-intestinal and foodborne infections: Laboratory reports for common bacterial, protozoal and viral infections 2009. Edinburgh: HPS; 2010. Available from: www.hps.scot.nhs.uk/giz/wrdetail.aspx?id=43840&wrtype=6
2. Cowden JM. Winter vomiting: Infections due to Norwalk-like viruses are underestimated. BMJ 2002;324:49-50.
3. Health Protection Scotland. Norovirus outbreak: control measures and practical considerations for optimal patient safety and service continuation in hospitals. Glasgow: HPS; 2009. Available from: www.documents.hps.scot.nhs.uk/hai/infection-control/toolkits/norovirus-c...
4. Marshall JA, Bruggink LD. Laboratory diagnosis of norovirus. Clin Lab 2006;52:571-81.
5. Moe CL, Liu P. Studies of Norovirus: Infectivity, Persistence and Reducuction. Center for Global Safe Water. Rollins School of Public Health. Emory University, Atlanta, GA.
6. Smith PW, Bennett G, Bradley S et al. SHEA/APIC guideline: infection prevention and control in the long-term care facility. Infect Control Hosp Epidemiol 2008;29(9):785-814.
7. World Health Organization (WHO). WHO Guidelines on Hand Hygiene in Health Care. First Global Patient Safety Challenge: Clean Care is Safer Care. Geneva: WHO; 2009. Available from: http://whqlibdoc.who.int/publications/2009/9789241597906_eng.pdf
8. Burnett E. Perceptions, attitudes and behaviour towards patient hand hygiene. Am J Infect Control 2009;37:638-42.