Chapter 2 - Transmission Based Precautions (TBPs)
Standard Infection Control Precautions (SICPs) may be insufficient to prevent cross transmission of specific infectious agents. Therefore additional precautions (TBPs) are required to be used by staff. SICPs must still be applied with these additional considerations.
TBPs should be applied when caring for:
- patients with symptoms of infection;
- asymptomatic patients who are suspected of incubating an infection; or
- patients colonised with an infectious agent.
TBPs are categorised by the route of transmission of infectious agents (some infectious agents can be transmitted by more than one route):
- Contact precautions: Used to prevent and control infections that spread via direct contact with the patient or indirectly from the patient’s immediate care environment (including care equipment). This is the most common route of cross-infection transmission.
- Droplet precautions: Used to prevent and control infections spread over short distances (at least 3 feet (1 metre)) via droplets (>5μm) from the respiratory tract of one individual directly onto a mucosal surface or conjunctivae of another individual. Droplets penetrate the respiratory system to above the alveolar level.
- Airborne precautions: Used to prevent and control infections spread without necessarily having close patient contact via aerosols (≤5μm) from the respiratory tract of one individual directly onto a mucosal surface or conjunctivae of another individual. Aerosols penetrate the respiratory system to the alveolar level.
Further information on Transmission Based Precautions can be found in the definitions of Transmission Based Precautions literature reviews.
Posters to display on the doors of patients being cared for under contact, droplet or airborne precautions and a TBP aide memoire are available in Resources.
2.1 Patient Placement/Assessment for Infection Risk
The potential for transmission of infection or infectious agents must be assessed at the patient’s entry to the care area and should be continuously reviewed throughout their stay. The assessment should influence placement decisions in accordance with clinical /care need(s).
Patients who may present a cross-infection risk include those:
- With diarrhoea, vomiting, an unexplained rash, fever or respiratory symptoms.
- Known to have been previously positive with a Multi-drug Resistant Organism (MDRO) e.g MRSA, CPE.
- Who have been hospitalised outside Scotland in the last 12 months.
These patients should be prioritised for placement in a suitable area to minimise cross transmission pending investigation e.g.
- In a single room with a clinical wash hand basin; or
- Cohort area/room with a clinical wash hand basin.
Patients being transferred by ambulance should be transported in accordance with Scottish Ambulance Service (SAS) local guidance.
Isolation within a care home for a known/suspected infection may be necessary to prevent spread. In most cases this can be achieved in the persons’ bedroom.
The clinical judgement and expertise of the staff involved in a patient’s management and the Infection Prevention and Control Team (IPCT) or Health Protection Team (HPT) should be sought particularly for patient placement decisions such as the application of TBPs e.g. isolation prioritisation when single rooms are in short supply.
For patients with a suspected/known infectious agent. Appendix 11 provides details of the route of transmission, optimal patient placement, duration of isolation and type of precautions required.
If multiple patient cases of the same infection are confirmed or if single rooms are unavailable, cohorting of patients may be appropriate. Patients should be separated by at least 3 feet (1m) if cohorted.
Consider assigning a dedicated team of care staff to care for patients in isolation/cohort rooms/areas as an additional infection control measure (staff cohorting). This can only be implemented if there are sufficient levels of staff available (so as not to have a negative impact on non-affected patients’ care).
Duration of isolation/cohort
Patient(s) should remain in isolation/cohort whilst they remain symptomatic and/or are considered infectious and the door must remain closed.
Before discontinuing isolation; individual patient risk factors should be considered (e.g. there may be prolonged shedding of certain microorganisms in immunocompromised patients); and the clinical judgement of those involved in the patient’s management should be sought.
Avoid unnecessary transfer of patients within/between care areas.
All patient placement decisions and assessment of infection risk (including isolation requirements) must be clearly documented in the patient notes.
Further information can be found in the Patient Placement (Isolation and Cohorting) literature review.
2.2 Safe Management of Patient Care Equipment in an Isolation Room/Cohort Area
- Use single-use items if possible.
- Reusable non-invasive care equipment should be dedicated to the isolation room/cohort area and decontaminated prior to use on another patient.
- An increased frequency of decontamination should be considered for reusable non-invasive care equipment when used in isolation/cohort areas.
For how to decontaminate non-invasive reusable equipment see Appendix 7.
Further information can be found in the management of patient care equipment literature review.
5Scottish Ambulance Service (SAS) and Scottish National Blood Transfusion Service adopt practices that differ from those stated in the National Infection Prevention and Control Manual.
2.3 Safe Management of the Care Environment
Routine environmental decontamination
Patient isolation/cohort rooms/area must be decontaminated at least daily using either:
- a combined detergent/disinfectant solution at a dilution of 1,000 parts per million available chlorine (ppm available chlorine (av.cl.)); or
- a general purpose neutral detergent in a solution of warm water followed by disinfection solution of 1,000ppm av.cl.
Increased frequency of decontamination should be incorporated into the environmental decontamination schedules for areas where there may be higher environmental contamination rates e.g.
- toilets/commodes particularly if patients have diarrhoea; and
- "frequently touched" surfaces such as door/toilet handles and locker tops, over bed tables and bed rails.
Equipment used for environmental decontamination must be either single-use or dedicated to the affected area then decontaminated following use e.g. mop and bucket.
Following patient transfer, discharge, or once the patient is no longer considered infectious:
Remove from the vacated isolation room/cohort area, all:
- healthcare waste and any other disposable items (bagged before removal from the room);
- bedding/bed screens/curtains and manage as infectious linen (bagged before removal from the room); and
- reusable non-invasive care equipment (decontaminated in the room prior to removal) Appendix 7.
The room should be decontaminated using either:
- a combined detergent disinfectant solution at a dilution (1,000ppm av.cl.); or
- a general purpose neutral detergent clean in a solution of warm water followed by disinfection solution of 1,000ppm av.cl..
The room must be cleaned from the highest to lowest point and from the least to most contaminated point. Manufacturers’ guidance and recommended product "contact time" must be followed for all cleaning/disinfection solutions .
Further information can be found in the environmental decontamination and terminal cleaning literature review.
6Scottish Ambulance Service (SAS) and Scottish National Blood Transfusion Service adopt practices that differ from those stated in the National Infection Prevention and Control Manual.
2.4 Personal Protective Equipment (PPE): Respiratory Protective Equipment (RPE)
Where it is not reasonably practicable to prevent exposure to a substance hazardous to health (as may be the case where healthcare workers are caring for patients with suspected or known airborne micro-organisms) the hazard must be adequately controlled by applying protection measures appropriate to the activity and consistent with the assessment of risk. If the hazard is unknown the clinical judgement and expertise of IPC/HPT is crucial and the precautionary principle should apply.
Respiratory Protective Equipment (RPE) i.e. FFP3 and facial protection, must be considered when a patient is admitted with a known/suspected infectious agent/disease spread wholly or partly by the airborne or droplet route and when carrying out aerosol generating procedures (AGPs) on patients with a known/suspected infectious agent spread wholly or partly by the airborne or droplet route.
The decision to wear an FFP3 respirator/hood should be based on clinical risk assessment that includes e.g task being undertaken, the infectious state of the patient, the presenting symptoms, risk of acquisition and the availability of treatment.
For a list of organisms spread wholly or partly by the airborne (aerosol) or droplet routes see Appendix 11.
The following risk categorisation is the minimum requirement for staff groups that require FFP3 fit testing. NHS Boards can add to this for example where high risk units are present. This categorisation is inclusive of out of hours services.
National Minimum Risk Categorisation for fit testing with FFP3
Level 1 – Preparedness for business as usual
Staff in clinical areas most likely to provide care to patients who present at healthcare facilities with an infectious pathogen spread by the airborne route; and/or undertake aerosol generating procedures i.e. A&E, ICU, paediatrics, respiratory, infectious diseases, anaesthesia, theatres, Chest physiotherapists, Special Operations Response Team (Ambulance), A&E Ambulance Staff, Bronchoscopy Staff, Resuscitation teams, Mortuary staff.
Level 2 – Preparedness in the event of emerging threat
Staff in clinical setting likely to provide care to patients admitted to hospital in the event of an emerging threat e.g. Medical receiving, Surgical, Midwifery and Speciality wards, all other ambulance transport staff. In the event of an ‘Epidemic/Pandemic’ Local Board Assessment as per their preparedness plans will apply.
All tight fitting RPE i.e FFP3 respirators must be:
- Fit tested on all healthcare staff who may be required to wear a respirator to ensure an adequate seal/fit according to the manufacturers’ guidance.
- Fit checked (according to the manufacturers’ guidance) every time a respirator is donned to ensure an adequate seal has been achieved.
- Compatible with other facial protection used i.e. protective eyewear so that this does not interfere with the seal of the respiratory protection. Regular corrective spectacles are not considered adequate eye protection.
- Donned and removed in a safe area (e.g. outside the isolation/cohort room/area).
Further information regarding fitting and fit checking of respirators can be found on the Health and Safety Executive website. Powered respirator hoods are an alternative to tight-fitting FFP3 respirators for example when fit testing cannot be achieved.
FFP3 respirator or powered respirator hood:
- may be considered for use by visitors if there has been no previous exposure to the infected person or infectious agent; but
- must never be worn by an infectious patient(s) due to the nature of the respirator filtration of incoming air not expelled air.
Powered hoods must be:
- Single use (disposable) and fluid repellent
- The filter must be enclosed with the exterior and the belt able to withstand disinfection with 10,000ppm av Chlorine
Further information can be found in the Respiratory Protective Equipment (RPE) literature review and the Personal Protective Equipment (PPE) for Infectious Diseases of High Consequence (IDHC) literature review.
Frameworks to support the assessing and recording of staff competency in PPE for IDHC are available in the resources section of the NIPCM.
2.5 Infection Prevention and Control during care of the deceased
The principles of SICPs and TBPs continue to apply whilst deceased individuals remain in the care environment. This is due to the ongoing risk of infectious transmission via contact although the risk is usually lower than for living patients.
Washing and/or dressing of the deceased should be avoided if the deceased is known or suspected to be harbouring invasive streptococcal infection, viral haemorrhagic fevers or other Group 4 infectious agents.
Details of pathogens can be found in Appendix 12. Key Infections from HSE Guidance “Controlling the risks of infection at work from Human Remains.
Staff should advise relatives of the precautions following viewing and/or physical contact with the deceased and also when this should be avoided.
Deceased individuals known or suspected to be harbouring a Group 4 infectious agent should be removed to a sealed double plastic body bag with absorbent material placed between each bag. The surface of the outer bag should then be disinfected with 1000ppm av.cl before being placed in a robust sealed coffin. This should be identified as a high risk and placed within a cold storage facility by mortuary staff whilst awaiting ongoing transport.
Further information can be found in the infection prevention and control during care of the deceased literature review.
- 2.1 Patient Placement/Assessment for Infection Risk
- 2.2 Safe Management of Patient Care Equipment in an Isolation Room/Cohort Area
- 2.3 Safe Management of the Care Environment
- 2.4 Personal Protective Equipment (PPE): Respiratory Protective Equipment (RPE)
- 2.5 Infection Prevention and Control during care of the deceased