About transmission based precautions (TBPs)

SICPs may be insufficient to prevent cross-transmission of specific infectious agents. Therefore, additional precautions known as transmission based precautions (TBPs) are required to be used by staff when caring for patients with a known or suspected infection or colonisation.

The way in which we describe transmission routes has changed. You can find out more about this in our ‘what’s changed’ guide. Our Frequently Asked Questions (FAQs) resource provides answers to some of the common queries associated with the changes. 

Transmission routes

Transmission routes are the ways in which an infectious agent spreads from one place or person to another.  Some infectious agents can be transmitted by more than one route. 

Contact transmission route

Transmission of infectious agents from one person to another by direct physical contact (direct contact transmission) or indirectly through contact with a contaminated object or surface (indirect contact transmission).

Air transmission route

Transmission of infectious agents from one person to another (without touching) via body fluids that travel from the infected person through the air. Air-transmitted infectious agents can be transmitted by splashing or spraying of body fluid particles onto the mucosa and/ or by inhaling body fluid aerosols.

Application of TBPs

Application of TBPs may differ depending on several factors. Clinical judgement and decisions should be made by staff on the necessary precautions.  This should be based on the:

• suspected or confirmed infectious agent
• transmission route of the infectious agent
• care setting and procedures undertaken
• severity of the illness caused

Respiratory infections

Respiratory infectious agents are mainly transmitted via the air transmission route. To support the application of TBPs, respiratory infectious agents have been grouped into three respiratory (R) categories: R1, R2 and R3. 

These categories take into account:

• severity of illness associated with infection,
• transmissibility
• associated availability of vaccination and treatments (prophylaxis)

Appendix 11 provides details of infectious agents, associated presentation or disease, the type of precautions, optimal patient placement, isolation requirements and respiratory (‘R’) category (for respiratory infectious agents).

If you want to understand more about how each pathogen is categorised, this is described in the NIPCM glossary under 'respiratory categories'.

Resources

Further information can be found in the Transmission Based Precautions Definitions literature review. 

2.1 Patient Placement/Assessment for transmission risk

The potential for transmission of infection must be assessed on the patient's arrival to the care area (or before arrival if possible), before transferring a patient to another care area and should be continuously reviewed throughout their stay. The assessment should support placement decisions in accordance with clinical or care need(s).

Patients who may present a transmission risk in any setting may include  those:

• with symptoms such as loose stools or diarrhoea, vomiting, fever or respiratory symptoms. 
• with a suspected or laboratory confirmed infectious agent for which appropriate duration of precautions as outlined in the A-Z of pathogens are not yet complete
• who are suspected or confirmed to have been previously positive with a Multi-drug Resistant Organism (MDRO), for example MRSA, CPE
• who have been hospitalised (inpatient) outside Scotland in the last 12 months (including those who received dialysis)

This is not an exhaustive list, and risks need to be assessed for each patient.

Further information regarding general respiratory screening questions can be found within the resources section of the NIPCM.

Within healthcare settings, different types of specialised ventilation isolation facilities are used to prevent transmission of infection.  Those most commonly found in NHS Scotland are;

• Negative pressure isolation room (NPIR)
• Positive pressure isolation room (PPIR)
• Positive Pressure Ventilated Lobby (PPVL) room

A description of these rooms and their intended use can be found in the glossary.

Isolation facilities should be prioritised depending on the suspected or confirmed infectious agent (refer to Appendix 11).  All patient placement decisions and assessment of infection risk (including isolation requirements) must be clearly documented in the patient notes.

• Patient placement should be reviewed daily, taking account of the clinical judgement and expertise of the staff involved in a patient's management. Where required, the advice of the Infection Prevention and Control Team (IPCT) or Health Protection Team (HPT) should be sought, for example, for isolation prioritisation when single rooms are in short supply.
• When specialised ventilated isolation is indicated but unavailable, the next best option should be considered with an appropriate risk assessment. Options are provided in Appendix 11.
• Those who are at increased risk of acquisition and adverse outcomes resulting from HAI should also be prioritised for placement in a single room.

Hospital settings

Patients who present transmission risk should be risk assessed and placed in appropriate isolation as follows:

• Patients with a suspected or confirmed R2 or R3 respiratory infectious agent, should be placed in a specialised negative pressure isolation room where available.

• • If this is not available, the patient should be placed in a single room when it is appropriate and following risk assessment.

• Patients with suspected or confirmed infection spread by the contact route, should be placed in a single room.
• Signage should be used on doors or areas to communicate isolation and TBP requirements.
• Doors to isolation rooms should be kept closed, where it is safe to do so.
• Infectious patients should only be transferred to other departments if medically necessary.  If the patient has an infectious agent transmitted by the air route, then, if possible or tolerated, the patient should wear a surgical face mask during transfer.
• Receiving department or hospital and transporting staff must be aware of the necessary precautions.

Cohorting in hospital settings

Cohorting of patients

Cohorting of patients should only be considered when single rooms are in short supply and should be undertaken in conjunction with the local IPCT.

Patients who should not be placed in multi bed cohorts:

• patients with different infectious agents or strains and patients with unknown infectious agents (laboratory confirmation still awaited)
• patients considered more vulnerable to infection
• patients who are unlikely to comply with TBPs

Patients with suspected infection should not be cohorted alongside  those with confirmed infection even if the same infectious agent is suspected.

• In such circumstances, suspected patients should be prioritised for single-room isolation.

Staff cohorting

Where possible, consider assigning a dedicated team of care staff to patients in isolation or cohort rooms as an additional infection control measure during outbreaks/incidents.

Primary care or out-patient settings

• Where possible, virtual assessments (by telephone, email or other appropriate media) of infection risk should be conducted for patients who are due to attend these settings.
• Patients attending these settings with suspected or confirmed infection or colonisation should be prioritised for assessment or treatment, for example scheduled appointments at the start or end of the clinic session. Infectious patients should be separated from other patients whilst awaiting assessment and during care management wherever possible.
• Patients should be asked to wear a surgical face mask if attending with a suspected or confirmed respiratory infection
• If transfer from a primary care facility to hospital is required, the ambulance service should be informed of the infectious status of the patient.

Additional considerations

Before discontinuing isolation in hospital settings

Individual patient risk factors should be considered, for example there may be prolonged shedding of certain infectious agents in immunocompromised patients. Clinical and, where appropriate, molecular tests to show the absence of microorganisms may be considered in the decision to discontinue isolation and can reduce isolation times. 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 on decisions regarding isolation discontinuation.

Residual respiratory exposure risk

If a patient vacating a room has a suspected or confirmed respiratory infection, the room may need to be left vacant for a period of time to ensure that any remaining potentially infectious particles are adequately cleared from the air to minimise the exposure risk to the next occupant. The clinical team should assess:

• the stage of infection, and whether the vacating patient continues to pose a transmission risk.
• the R category of the infectious agent (R1, R2, or R3), and the vulnerability of the incoming patient

If a vacancy period is required, and should a healthcare worker need to enter the room during the vacancy period, healthcare workers should wear appropriate PPE: a surgical mask or respiratory protective equipment (RPE) should be used in line with the respiratory category associated with the vacating patient. Refer to Appendix 15. This would include when undertaking cleaning post discharge.

See Hierarchy of Controls (engineering controls) for information on the impact of ventilation on clearance times.

Ensure a minimum of 10 minutes has passed to allow the largest particles to settle on surfaces before terminal decontamination – see terminal decontamination for additional information.

Resources

Further information can be found in the patient placement literature review.

2.2 Safe Management of non-invasive, reusable, shared care equipment in an Isolation Room/Cohort Area

• Use single-use items if possible.
• Non-invasive, reusable, care equipment should be dedicated to the isolation room or cohort area and decontaminated prior to use on another patient Section 1.5. Safe Management of Care Equipment.
• An increased frequency of decontamination should be considered for non-invasive, reusable, care equipment when used in isolation or cohort areas.
• Detergent, disinfectant or combination products should be prepared and used according to manufacturer instructions including chemical concentration, application style and contact time, whilst taking into account the specific equipment manufacturers instructions.

Resources

For how to decontaminate non-invasive reusable equipment see Appendix 7.

2.3 Safe Management of the Care Environment

Routine environmental decontamination

Hospital setting

Patient isolation/cohort rooms/area should be decontaminated at least daily, this may be further increased on the advice of IPCTs/HPTs. These areas should be decontaminated using either:

• A detergent followed by a disinfectant solution

or

• A combination product

Manufacturer’s instructions should always be followed regarding preparation and use of a detergent, disinfectant or combination products.

Increased frequency of decontamination/cleaning schedules should be incorporated into the environmental decontamination schedules for areas where there may be higher environmental contamination rates, for example 

• toilets/commodes particularly if patients have diarrhoea
• “frequently touched” surfaces such as door/toilet handles and locker tops, over bed tables and bed rails

Patient rooms must be terminally decontaminated following resolution of symptoms, discharge or transfer. This includes removal and laundering of all curtains and bed screens.

Primary care/out-patient settings

The extent of decontamination between patients will depend on the duration of the consultation/assessment, the patients presenting symptoms and any visible environmental contamination. 

Equipment used for environmental decontamination must be either single-use or dedicated to the affected area then decontaminated or disposed of following use for example cloths, mop heads.

Terminal decontamination

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)
• non-invasive, reusable, care equipment should be decontaminated prior to removal from the area

The room should be decontaminated using either:

• A detergent followed by a disinfectant solution

or

• A combination product

The room should be cleaned from the highest to lowest point and from the least to most contaminated point.

Manufacturer’s instructions should always be followed regarding preparation and use of detergent, disinfectant or combination products.

If a patient vacating a room has a suspected or confirmed respiratory infection, healthcare workers should wait a minimum of 10 minutes before commencing terminal decontamination. This allows larger respiratory particles to settle onto surfaces. 

For longer vacancy periods, see patient placement considerations.

 

2.4 Personal Protective Equipment (PPE)

All PPE should:

• be located close to the point of use
• be stored in a clean and dry area to prevent contamination until needed for use
• be within expiry dates
• be single-use only items unless specified as reusable by the manufacturer
• be checked for any damage or defects before donning
• be changed immediately after use and/or following completion of a procedure or task
• be disposed of after use into the correct waste stream
• not be worn inappropriately outside of care delivery for example, moving around corridors, at IT work stations or non-clinical areas

2.4.1   Gloves

Gloves should:

• not be worn as a substitute to hand hygiene

• be worn when exposure to blood, body fluids, (including but not limited to secretions and/or excretions), non-intact skin, lesions and/or vesicles, mucous membranes, hazardous drugs and chemicals, e.g. cleaning agents is anticipated/likely
  • Gloves are a single-use item and should be donned immediately prior to exposure risk and should be changed immediately after each use or upon completion of a task
• never be worn inappropriately in situations such as to go between patients, move around a care area, work at IT workstations
• be changed if a perforation or puncture is suspected or identified
• be appropriate for use, fit for purpose and well-fitting

Double gloving is only recommended during some Exposure Prone Procedures (EPPs), for example orthopaedic and gynaecological operations, or when attending major trauma incidents and when caring for a patient with a suspected or known High Consequence Infectious disease.  Double gloving is not necessary at any other time.

Resources

For appropriate glove use and selection see Appendix 5.

Further information can be found in the Gloves literature review.

2.4.2  Aprons and Gowns

The type of aprons or gowns used in health and care settings should be selected based on the task being undertaken, and the anticipated levels of body fluid exposure.

A disposable apron should be worn when in contact with a patient’s environment or when providing direct care to those suspected or confirmed to be colonised or infected with a transmissible infectious agent.

A fluid repellent gown should be used if excessive splashing or spraying is anticipated.

Resources

Further information can be found in the Aprons/Gowns literature review.

2.4.3  Eye and face protection

Eye and face protection should be worn:

• when there is an anticipated risk of splashing and/or spraying of blood or body fluids

Types of eye or face protection suitable for use include goggles, face shields or visors, and surgical face masks with integrated face shields. Prescription eyeglasses and contact lenses should not be considered a form of eye or face protection.

2.4.4  Fluid resistant surgical masks (FRSM)

Fluid resistant surgical masks should be:

• worn when a patient presents with symptoms indicative of a transmissible respiratory infection and the infectious agent has not yet been determined
• worn when caring for a patient with a suspected or confirmed R1 respiratory infection– see Appendix 15 for RPE options.
• donned prior to entry to, and for the duration within, areas containing patients who are suspected or confirmed to have an R1 respiratory infection
• worn by patients with a suspected or confirmed transmissible respiratory infection when a healthcare worker enters their room, whilst outside their room, and whilst being moved or transported to other departments, where it is clinically safe to do so and can be tolerated by the wearer.
• worn by healthcare workers, visitors and patients (where tolerated and does not compromise clinical care) during epidemics or periods of increasing or high rates of local transmission of respiratory infection within healthcare areas. Local health boards may undertake a risk assessment and advise extended use of FRSMs as part of a suite of control measures.  Local epidemiology should be used to inform the risk assessment.

FRSMs may be worn sessionally when providing care to a cohort of patients with the same confirmed respiratory infection.  Sessional use of a FRSM means that staff do not need to change these when moving between patients within the cohort however the FRSM should be changed if it becomes damaged or contaminated.  Other items of PPE should not be used sessionally and should be changed between procedures/tasks and patients as indicated.  

Transparent face masks may be used

• when there are communication barriers
• if they meet the specifications of BS EN 14683:2025  

2.4.5  Respiratory Protective Equipment (RPE)

RPE should be worn when caring for a person with a suspected or confirmed R2 or R3 respiratory infection.

RPE may be worn when caring for a person with a suspected or confirmed R1 respiratory infection if the staff member has been advised to do so by occupational health, GP, or another personal medical practitioner.

RPE should be changed after each use. Other indications that a change is required include:

• if breathing becomes difficult
• if the respirator becomes wet or moist
• if the respirator is damaged or contaminated

Staff may choose to wear RPE where FRSM is indicated for use when caring for a patient with a suspected or confirmed R1 respiratory infection, based on personal choice. Refer to Appendix 15.

RPE should never be worn by an infectious person as the respirator filters incoming air and not the air being expelled by the wearer.

There are two main types of respirators used within health and care settings in Scotland:

• tight-fitting respirators (FFP3) that require the wearer to be face fit tested, and to perform a fit check on each use
• loose fitting respirators (often referred to as powered hoods, powered respirators or PAPR)

 

Filtering Face Piece 3 (FFP3) Respirators

RPE should be changed after each use. Other indications that a change is required include:

• if breathing becomes difficult
• if the respirator becomes wet or moist
• if the respirator is damaged or contaminated

FFP3 respirators with unshrouded valves are not considered to be fluid resistant. Where there is a risk of splash contamination for the wearer with blood or body fluids additional PPE should be worn, such as a full face shield/visor.

Valved RPE respirators should not be worn when a sterile field is required. An MHRA safety alert can be viewed. 

FFP3 respirators should be compatible with other facial protection used, for instance eye protection, so that this does not interfere with the seal of the respiratory protection.

The wearer should be clean shaven and free of any jewellery or piercings to support effective fit testing by ensuring a smooth surface area for a seal. The Facial Hairstyles and Filtering Facepiece Respirators poster gives further information on compatibility of facial hair and FFP3 respirators and can be used when fit testing and fit checking.

Fit testing

All tight-fitting RPE (for instance FFP3 respirators) must be face fit tested. Face fit testing should be:

• conducted by a competent fit tester as outlined by British and International Standards BS ISO 16975-3: 2017
• recorded for each individual, including mask brand, style, model and size
• repeated if changing brand, style, model brand or size
• repeated following reported or observed changes to the wearer’s face that could impair the seal (for example, due to weight loss or gain, dental or cosmetic work)

Fit checking

A fit check should be performed each time tight fitting RPE is donned, to ensure a tight seal has been achieved. A fit check is not a substitute for fit testing.

If a fit test or check fails, then the RPE should be adjusted and fit test/check repeated. If a tight seal cannot be achieved then other types of RPE that offer equivalent protection may be considered.

Staff should not undertake tasks where RPE is required if a fit test or a fit check has failed and alternative RPE is unavailable.

Resources

Poster on Facial Hairstyles and Filtering Facepiece Respirators can be used when fit testing and fit checking

See Appendix 6 for donning and doffing advice.

Further information regarding fitting and fit checking of respirators can be found on the Health and Safety Executive website.

Powered respirator hoods

Powered respirator hoods are an alternative to FFP3 respirators for example when fit testing cannot be undertaken or achieved.

Where feasible, reusable components (for example, powered hoods and helmets) should be issued for individual use.

Powered hoods should be:

• single-use (disposable) and fluid resistant
• the filter must be enclosed with the exterior and the belt decontaminated following the manufacturer’s instructions.

Donning and Doffing RPE

Donning (putting on)

• RPE should be checked for any damage or defects before donning.
• Donning RPE should be performed in line with manufacturer’s instructions.
• Hand hygiene should be performed before donning RPE
• If using an FFP3 respirator, a fit check should be performed once donned to ensure a tight seal has been achieved.
• RPE should be donned outside of the patient’s room or care area, or within an ante room.
• Once donned (and following fit check for FFP3 respirator use), the front of the RPE should not be touched.

Doffing (Removing)

• RPE must be removed after exiting the care area or room.
• Where worn with other items of PPE, RPE should be removed last.
• FFP3 respirators should be removed using only the straps to minimise contact with the outside surface.
• Hand hygiene should be performed before and after removal of RPE.

Further information can be found in the Respiratory Protective Equipment (RPE) literature review and the Personal Protective Equipment (PPE) for High Consequence Infectious Diseases (HCIDs) Literature review.

PPE should always be used in line with SICPs and as below as part of TBPs.

TBP PPE summary table:

Gloves	Aprons	Gowns	Eye/Face protection	Fluid Resistant Surgical Masks (FRSM)	Respiratory Protective Equipment (RPE)
As per SICPs	As per SICPs	As per SICPs	When there is an anticipated risk of splashing and/or spraying of blood or bodily fluids.	When caring for a person with suspected or confirmed respiratory infection and the infectious agent has not yet been determined. When caring for a person with suspected or confirmed R1 respiratory infection.	Worn when caring for a person with a suspected or confirmed R2 or R3 respiratory infection. Worn following a personal assessment (medical or choice) – see Appendix 15.

 

 

PPE for visitors

Visitors do not routinely require PPE unless they are providing direct care to the individual they are visiting. 

However, if visiting a patient with a suspected or confirmed respiratory infection, visitors may be offered a FRSM to wear for the duration of the visit. Consideration should be given to providing visitors with RPE when visiting a patient with a suspected or confirmed infection caused by a category R2 or R3 respiratory infectious agent. Note: If the R2 or R3 infectious agent is a HCID, visiting must be discussed with your local IPCT.

If the need for PPE is identified, staff should provide advice on its correct use. This must include fit testing for FFP3 (if required), advice on fit checking and appropriate donning and doffing for all PPE.

If, following an explanation of potential risks, a visitor declines to wear PPE when it is offered, then this should be respected, and the visit should not be refused. PPE use by visitors cannot be enforced and there is no expectation that staff monitor PPE use amongst visitors.

The table below shows the PPE which should be worn where appropriate and when the visitor chooses to do so.

TBP PPE summary table for visitors:

Gloves	Apron	FRSM	RPE	Eye or Face Protection
Not required unless providing direct care, which may expose the visitor to blood and/or body fluids, for instance assisted toileting or feeding.	Not required unless providing care resulting in direct contact with the service user, their environment or blood and/or body fluid exposure, for instance toileting, bed bath. A gown may be used where excessive splashing or spraying may be anticipated.	Where splash or spray to nose or mouth is anticipated AND for the duration of a visit to a patient with suspected or confirmed respiratory infection. During essential visiting arrangements when the visitor has a suspected or confirmed transmissible respiratory infection.	When visiting someone who has a suspected or confirmed R2, R3 infection	Where splash or spray to the visitor's eyes/face is anticipated

 

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 the contact route. 

It is important that information on the infection status of the deceased is sought and communicated at each stage of handling. Appropriate risk assessment must be carried out before performing activities that may increase the risk of transmission of infectious agents from deceased individuals (see literature review for further information on these activities).

Washing and/or dressing should not be carried out when the deceased is known or suspected to have been infected by any of the following key infectious agents: ACDP Hazard Group 4 organisms, anthrax, and rabies. For other HCIDs a local risk assessment should be undertaken to inform any decision making on washing and/or dressing of the deceased.

Viewing of the deceased should be avoided when the deceased is known or suspected to have been infected by ACDP Hazard Group 4 organisms, specifically those causing VHFs (including Ebola, Lassa etc.) and anthrax. For other HCIDs a local risk assessment should be undertaken to inform any decision making on viewing of the deceased.

See Appendix 12 Application of infection control precautions in the deceased.

Staff should advise relatives of the appropriate precautions when viewing and/or having physical contact with the deceased including when this should be avoided.

Deceased individuals known or suspected to have a ACDP Hazard Group 4 infectious agent should be placed in a sealed double plastic body bag with absorbent material placed between each bag. A product should then be used to decontaminate the outside of the bag, following the manufacturer’s instructions. Once it has been disinfected, place the bag into a robust, sealed coffin.

Post-mortem examination should not be performed on a deceased individual known or suspected to have a ACDP Hazard Group 4 infectious agents.  See Appendix 12 Application of infection control precautions in the deceased. Blood sampling can be undertaken in the mortuary by a competent person to confirm or exclude this diagnosis.  Refer to Section 2.4  or, for suspected or confirmed HCIDs, the HCID addendum for suitable PPE. 

Post-mortem examination of deceased individuals known or suspected to have been infected by transmissible spongiform encephalopathies (TSE) causing agents should be carried out in such a way as to minimise contamination of the working environment. See Literature review for further information.