Rabies exposure and prophylaxis

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Rabies virus is a neurotropic lyssavirus present in saliva of infected mammals. Transmission usually follows a bite but scratches, mucosal contamination and saliva on broken skin also matter. UK terrestrial mammals are rabies-free, but imported animals and overseas exposures remain relevant; UK bats can carry European bat lyssaviruses.

After inoculation, virus may replicate locally and enter peripheral nerves at neuromuscular junctions. Retrograde axonal transport carries it to spinal cord and brain, followed by centrifugal spread to salivary glands and other tissues. The clinically silent interval creates the opportunity for wound cleansing, neutralising antibody and active immunisation.

Exposure assessment determines whether post-exposure treatment is required. Country risk, species, animal health and availability, exact contact and host immunity interact; none can be assessed safely from a single generic category. UK clinicians therefore use the current UKHSA algorithm and Rabies and Immunoglobulin Service rather than improvising from older schedules.

Once neurological symptoms appear, vaccine and immunoglobulin do not reverse established neuronal infection. Management becomes intensive supportive care, diagnostic confirmation, staff and contact risk assessment, and public-health control. Survival is exceptionally rare, making prompt pre-symptom prophylaxis the decisive intervention.

Key points

Rabies virus and related lyssaviruses are transmitted when infectious saliva from a mammal reaches broken skin or mucosa; dogs cause most human rabies globally.
Immediately wash every wound with soap and running water for about 15 minutes, irrigate thoroughly and apply a virucidal antiseptic when available.
Record country, exact location and date, animal species and behaviour, provoked or unprovoked contact, ownership, vaccination, availability for observation or testing, wound site and depth.
Contact the UKHSA Rabies and Immunoglobulin Service for individual green, amber or red risk allocation; do not substitute a remembered country list for the current algorithm.
A non-immunosuppressed person who is not fully immunised and has an amber or red exposure generally receives four intramuscular vaccine doses on days 0, 3, 7 and 21.
A fully immunised, non-immunosuppressed person with an amber or red exposure generally receives two vaccine doses on day 0 and day 3 to 7, without routine HRIG.
An immunosuppressed exposed person receives HRIG when indicated and five vaccine doses on days 0, 3, 7, 14 and 30, with specialist assessment of response.
When UKHSA authorises human rabies immunoglobulin, use 20 IU/kg and infiltrate as much as anatomically feasible into and around all wounds; never exceed the calculated dose.
Pregnancy and breastfeeding are not contraindications to post-exposure vaccination or immunoglobulin because untreated rabies risk is catastrophic.
Rabies is clinician-notifiable in England; suspected symptomatic disease requires immediate health-protection, infection, neurology and critical-care coordination.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Rabies virus

Classical rabies virus is a Lyssavirus carried by mammals and transmitted chiefly through virus-containing saliva from an infectious animal.

Dog-mediated transmission

Domestic dogs cause most human deaths globally, particularly where canine vaccination and access to post-exposure products are limited.

Bat lyssaviruses

Bats carry rabies-related lyssaviruses across regions, including European bat lyssaviruses in the UK, and bites may be inconspicuous.

Saliva inoculation

Bites, scratches, mucosal splashes and contamination of broken skin transmit infection; intact-skin contact is not an exposure.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Local replication
Virus can replicate in muscle and connective tissue near the inoculation site before entering motor or sensory nerves.
2
Retrograde neural spread
Lyssavirus travels through peripheral axons towards spinal cord and brain, largely protected from circulating antibody after neural entry.
3
Encephalomyelitis
Widespread neuronal dysfunction causes behavioural change, phobic spasms, dysautonomia, cranial-nerve disturbance, progressive paralysis and ultimately fatal respiratory failure.
4
Centrifugal dissemination
Virus spreads outward through nerves to salivary glands, skin and other tissues, enabling transmission during symptomatic disease.
5
Prophylactic interception
Wound cleansing, local passive antibody and active vaccine immunity neutralise virus before irreversible central nervous system entry.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Relevant bite or scratchRed flag

Teeth or claws breach skin in a risk country or through direct bat contact, allowing saliva-contaminated inoculation.

Mucosal or broken-skin exposureRed flag

Saliva reaches eye, mouth, nose or an existing abrasion even when no bite mark is visible.

Prodromal rabiesRed flag

Fever, headache, malaise and distinctive pain, itching or paraesthesia at a healed exposure site precede neurological deterioration.

Furious rabiesRed flag

Agitation, fluctuating confusion, phobic inspiratory spasms triggered by water or air, hypersalivation and autonomic instability dominate.

Paralytic rabiesRed flag

Flaccid weakness begins near the exposure and ascends, eventually causing sphincter, bulbar and respiratory failure without classic hydrophobia.

Advanced diseaseRed flag

Coma, seizures, arrhythmia, haemodynamic instability, respiratory failure and multiorgan complications precede death in most symptomatic cases.

Red flags requiring action

A transdermal bite or scratch, saliva on broken skin or mucosa, or direct bat exposure in a rabies-risk setting needs urgent formal assessment.
Headache, fever, paraesthesia or pain at the bite followed by agitation, hydrophobia, aerophobia, dysphagia or autonomic instability suggests furious rabies.
Ascending flaccid weakness after an animal exposure may be paralytic rabies and can be mistaken for Guillain–Barré syndrome.
A bite to the face, head, neck, hand or genitals, multiple deep wounds or exposure in a child increases concern because innervation and inoculum may shorten risk pathways.
Immunosuppression changes the post-exposure schedule and requires HRIG plus five vaccine doses even when previous vaccination history appears reassuring.
Do not postpone prophylaxis while trying to source the animal or await laboratory testing unless UKHSA explicitly advises that observation or testing resolves the risk.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
Structured exposure historyFirst step
Why
Provide the information UKHSA needs to allocate green, amber or red risk.
Interpretation and limitations
Document exact country and place, date, species, ownership, behaviour, health, vaccination, observation or test availability, contact type, wound and prior prophylaxis.
02
Wound examination
Why
Identify every inoculation site and guide cleansing, HRIG infiltration and surgical care.
Interpretation and limitations
Undress and inspect fully, including scalp and digits in children; document number, depth, nerve or tendon injury, contamination, infection and mucosal exposure.
03
Previous vaccine verification
Why
Determine whether a person meets the current fully immunised definition and select the correct schedule.
Interpretation and limitations
Check dates, products, routes and documentary evidence for pre-exposure or post-exposure courses; uncertain or incomplete records require UKHSA interpretation, not assumption.
04
Animal observation or testing
Why
Refine risk only when validated public-health or veterinary arrangements are available.
Interpretation and limitations
Do not personally arrange unsafe capture or delay treatment; UKHSA determines whether species-specific observation, laboratory testing or subsequent course cessation is valid.
05
Rabies antibody measurement
Why
Assess response in selected immunosuppressed people or after non-standard vaccination rather than diagnose routine exposure.
Interpretation and limitations
Send only with UKHSA or specialist advice at the specified interval; vaccine response does not replace indicated wound care and immediate prophylaxis.
06
Reference testing for symptomatic disease
Why
Confirm rabies or another lyssavirus while protecting staff and preserving sample quality.
Interpretation and limitations
Coordinate saliva PCR, nuchal skin biopsy, serum and CSF antibody or other samples with UKHSA and the reference laboratory; repeated specimens may be necessary.
07
Alternative encephalitis assessment
Why
Treat reversible causes of fever, encephalopathy, dysphagia, seizures or paralysis in parallel.
Interpretation and limitations
Use blood cultures, metabolic tests, neuroimaging, CSF and pathogen testing only within an infection-control plan that accounts for saliva exposure risk.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Viral or autoimmune encephalitis

Herpes simplex, arboviruses and autoimmune encephalitis cause fever, seizures and behavioural change without the characteristic exposure sequence.

Tetanus

Trismus, painful spasms and autonomic instability follow contaminated wounds, but consciousness is preserved and hydrophobic inspiratory spasms differ.

Guillain–Barré syndrome

Ascending flaccid paralysis resembles paralytic rabies; exposure history, pain or paraesthesia at the bite and reference testing help distinguish them.

Toxic or metabolic states

Strychnine, stimulant intoxication, porphyria, severe withdrawal and metabolic encephalopathy can produce agitation, spasms or autonomic instability.

Psychiatric presentation

Acute psychosis or panic may resemble early furious rabies, but organic signs and a plausible exposure require urgent exclusion.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01FIRST AIDClean before anything elseFirst stepA possible rabies exposure has just occurred or presents with an untreated wound.

1Wash and flush wounds immediately with soap and running water for about 15 minutes, then use a virucidal antiseptic such as povidone-iodine when available.
2Remove visible foreign material and assess tendon, nerve, vascular and infection damage; update tetanus and manage ordinary bacterial bite risk separately.
3Avoid primary tight closure where possible; if closure is necessary, infiltrate authorised HRIG first and use minimal loose suturing after surgical advice.
4Do not apply irritants, cautery or a tight tourniquet, and do not allow excellent wound care to delay contact with UKHSA.

02RISK ASSESSObtain current UKHSA allocationSaliva contact with broken skin or mucosa, a bite or scratch, or direct bat exposure may have occurred.

1Gather the full exposure history, wound map, immune status, pregnancy status and documentary vaccine history before calling when clinically feasible.
2Contact the Rabies and Immunoglobulin Service or out-of-hours health-protection route for a green, amber or red classification and product advice.
3Begin treatment promptly when indicated even if the exposure occurred weeks or months earlier, provided neurological rabies has not begun.
4Reassess when credible animal observation or laboratory results become available, but change or stop a course only with UKHSA advice.

03VACCINATEFollow immunity-specific schedulesUKHSA classifies the exposure as needing post-exposure vaccine.

1For a non-immunosuppressed person who is not fully immunised, give intramuscular vaccine on days 0, 3, 7 and 21 for amber or red risk.
2For a fully immunised, non-immunosuppressed person, give vaccine on day 0 and day 3 to 7; routine HRIG is not used.
3For an immunosuppressed person, give five vaccine doses on days 0, 3, 7, 14 and 30 plus HRIG when advised, and arrange antibody follow-up.
4Give vaccine into the deltoid, or anterolateral thigh when appropriate in a young child, never the buttock; resume rather than restart after most delays following UKHSA advice.

04HRIGNeutralise virus at the woundUKHSA authorises human rabies immunoglobulin under the current exposure and supply criteria.

1Calculate 20 IU/kg once and do not exceed it, because excess passive antibody can blunt the active vaccine response.
2Infiltrate as much of the calculated dose as anatomically safe into and around every wound, using dilution only according to current product and UKHSA instructions when needed.
3Give any authorised remainder intramuscularly at a site distant from vaccine; never mix HRIG and vaccine in the same syringe or anatomical site.
4Do not give HRIG later than seven days after the first vaccine dose, or after the second vaccine dose, unless the current UKHSA algorithm specifically directs otherwise.

05SYMPTOMATICEscalate suspected clinical rabiesEscalationCompatible encephalitis, hydrophobia, aerophobia, dysphagia or progressive paralysis follows a possible exposure.

1Isolate the patient, use appropriate personal protective equipment for saliva and airway procedures, and call infection, neurology, critical care and health protection immediately.
2Notify suspected rabies urgently and coordinate reference testing before collecting high-risk samples or undertaking aerosol-generating procedures.
3Provide symptom control, airway and organ support with honest prognostic communication; no antiviral or induction-coma protocol has proven reliable efficacy.
4Identify staff and contacts with mucosal or broken-skin exposure to saliva or neural tissue for separate UKHSA risk assessment; casual proximity is not an exposure.

Key medicines and prescribing safety4 treatments · regimens, roles and cautions

Active post-exposure immunisation that generates neutralising antibody before virus reaches the central nervous system.

Rabies vaccine for non-fully immunised exposure

Give one full intramuscular dose on days 0, 3, 7 and 21 for a non-immunosuppressed person with UKHSA-classified amber or red risk who is not fully immunised.

Use the product-specific full dose regardless of body weight, inject into the deltoid rather than buttock, document batch and timing, and do not withhold because of pregnancy or breastfeeding.

Rapid booster response after a documented complete pre-exposure or post-exposure course accepted by UKHSA.

Rabies vaccine after full immunisation

Give one full intramuscular dose on day 0 and a second on day 3 to 7 for a fully immunised, non-immunosuppressed person with amber or red risk.

Confirm that the previous regimen meets the current fully immunised definition; uncertain documents, intradermal schedules, immunosuppression or major delay require UKHSA interpretation.

Immediate passive neutralising antibody at the inoculation site until active vaccine immunity develops.

Human rabies immunoglobulin

When authorised, calculate 20 IU/kg once, infiltrating as much as anatomically feasible into and around all wounds and giving any advised remainder intramuscularly distant from vaccine.

Current UKHSA interim allocation criteria govern use; never exceed the dose, never share an injection site or syringe with vaccine, and generally do not administer after day 7 from first vaccine.

Enhanced post-exposure schedule for hosts whose active antibody response may be delayed or inadequate.

Rabies vaccine for immunosuppressed exposure

Give full intramuscular doses on days 0, 3, 7, 14 and 30, plus HRIG when advised, for an immunosuppressed exposed person under UKHSA supervision.

Define immune suppression with specialist input, arrange neutralising-antibody measurement when instructed, and do not infer protection solely from previous vaccination.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Respiratory failure

Bulbar dysfunction, inspiratory spasms, aspiration, paralysis and central respiratory dysregulation ultimately compromise ventilation and airway protection.

Autonomic collapse

Labile blood pressure, arrhythmias, myocarditis, temperature disturbance and cardiac arrest reflect severe brainstem and autonomic involvement.

Secondary intensive-care injury

Prolonged ventilation brings aspiration, pneumonia, thrombosis, pressure injury, line infection, delirium and treatment-related multiorgan complications during intensive care.

Contact exposure

Unprotected mucosal or broken-skin contact with saliva or neural tissue can create additional exposures among carers or laboratory staff.

Death

Symptomatic rabies is almost invariably fatal despite intensive support, which makes correct pre-symptom prophylaxis uniquely important.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Record every product, batch, dose, route, anatomical site and date, then give the patient a written schedule with a named service responsible for each remaining dose.
Actively recall missed doses and obtain UKHSA advice on timing; most interruptions are resumed rather than restarting the entire series.
Observe for immediate vaccine or immunoglobulin reactions according to local policy, while recognising that mild local reactions are not a reason to abandon life-saving prophylaxis.
Check wound healing, bacterial infection, function and tetanus status independently of rabies prophylaxis, especially after hand, facial, deep or crush injuries.
For immunosuppressed recipients, arrange the specified rabies neutralising-antibody test and additional dose plan through UKHSA.
Update the risk assessment if reliable animal observation or laboratory results arrive, documenting who authorised any change to the schedule.
For symptomatic cases, maintain an exposure log for staff and visitors and reassess any saliva or neural-tissue incident immediately.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

Washing is biological treatment

Prolonged soap-and-water irrigation physically removes and inactivates virus at the site before it enters peripheral nerves.

The buttock is the wrong site

Variable deposition into gluteal fat can reduce vaccine response, so intramuscular doses use deltoid or appropriate anterolateral thigh.

HRIG belongs in the wound

Passive antibody is most valuable where virus was inoculated, making careful infiltration more important than a remote injection alone.

Long delay does not erase benefit

An exposed asymptomatic person can still need prophylaxis after a delayed presentation because incubation may last months or longer.

Bats need special attention

Tiny teeth can leave inapparent marks, and UK bats may carry European bat lyssaviruses despite freedom from terrestrial rabies.

Scope boundary

Rabies-specific prophylaxis is detailed here; traumatic wound repair, tetanus, bacterial bite infection and generic encephalitis care proceed in parallel.

11Common pitfallsFrequent interpretation and management errors.

01
Do not wait for symptoms before acting; post-exposure prophylaxis prevents disease but cannot reliably rescue established neurological rabies.
02
Do not close a high-risk wound tightly before adequate irrigation and authorised immunoglobulin infiltration.
03
Do not use a static internet country category or an old printed schedule instead of current UKHSA individual assessment.
04
Do not inject rabies vaccine into the buttock or combine it with HRIG in the same syringe or site.
05
Do not exceed 20 IU/kg HRIG or administer it late without specific UKHSA instruction.
06
Do not withhold indicated prophylaxis because the patient is pregnant or breastfeeding.
07
Do not classify casual contact with a symptomatic patient as exposure, but assess saliva contact with mucosa or broken skin urgently.