Vaccine administration practices: Canadian Immunization Guide

For health professionals

Last partial content update: May 2023
  • The section on "Route, site and technique for vaccine administration" was updated to expand on the administration of intradermal injections.
  • This information is captured in the table of updates.

Last complete chapter revision (see table of updates): November 2017

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General considerations

Appropriate vaccine administration is essential to the optimal safety and efficacy of vaccines. Vaccine administration practices are based on clinical trials that determine the dose, route and schedule for each vaccine. Professional standards for medication and vaccine administration, and jurisdictional or organizational policies and procedures (if available) also guide vaccination practices.

All vaccine providers should receive education and competency-based training on vaccine administration before providing vaccines to the public. Programs should be in place to monitor the quality of immunization services. For detailed information about the recommended immunization competencies, refer to the Public Health Agency of Canada's Immunization Competencies for Health Professionals.

This chapter provides general guidance regarding vaccine administration practices, for use in conjunction with vaccine manufacturers' instructions as outlined in product leaflets and product monographs; professional standards of practice; and jurisdictional or organizational policies and procedures. The general principles regarding vaccine administration also apply to administration of passive immunizing agents.

Pre-vaccination counselling

Prior to vaccination, the vaccine provider should:

After informed consent is obtained, the vaccine provider should outline the process of vaccine administration and explain positioning procedures. The parent or guardian should hold a child in a position as instructed by the vaccine provider. Failed positioning can result in loss of part or the entire dose, inappropriate depth of injection, or injury to the vaccine recipient or vaccine provider. Refer to Positioning for information about positioning procedures. Refer to Table 4 for education for healthcare providers about immunization pain management strategies. Table 1 provides an example pre-vaccine administration checklist.

Table 1: Pre-vaccine administration check list
Screening questions for all vaccinesTable 1 - Footnote 1 Yes No
  1. Is the vaccine indicated according to the recommended immunization schedulesTable 1 - Footnote 2 and the vaccine recipient's immunization history?
   
  1. Has information been provided regarding administration of the vaccine as well as the benefits and risks of receiving or not receiving the vaccine?
   
  1. If the vaccine recipient is a woman, is she pregnant, or is there a chance that she may be pregnantTable 1 - Footnote 3?
   
  1. Has the vaccine recipient ever had a serious reaction (e.g., anaphylactic reaction) after receiving a vaccine or is the recipient aware of any allergies to components of the vaccineTable 1 - Footnote 4, or latex?
   
  1. Has the vaccine recipient or appropriate guardian or substitute decision-maker provided consent to vaccination and been offered an opportunity to ask questions?
   
Additional screening questions if immunizing with live vaccines YesTable 1 - Footnote 5 No
  1. Does the vaccine recipient have any acute or chronic immunocompromising condition or have they taken any medications in the past 3 months that cause immunosuppression, including corticosteroids?

    If giving a live vaccine to an infant, consider:

    1. Is there a known or suspected family history of congenital immunodeficiency disorder or HIV infection, or a history of failure to thrive AND recurrent serious infections?
    2. Has the mother taken any immunosuppressive medications during pregnancy?
   
  1. Has the vaccine recipient received any other live vaccines in the past 4 weeks?
   
  1. Has the vaccine recipient received any transfusions of blood or blood products in the last year?
   
PTable 1 - Footnote 1

Refer to vaccine-specific chapters in Part 4 for vaccine-specific screening questions.

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Table 1 - Footnote 2

Vaccines may also be recommended based on risks related to occupation, travel, chronic disease, immunocompromising condition or for post-exposure prophylaxis. Refer to Immunization of workers, Immunization of travellers, Immunization of persons with chronic diseases, or Immunization of immunocompromised persons in Part 3 for additional information.

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Table 1 - Footnote 3

Pregnancy may be a contraindication for some vaccines. Refer to Immunization in pregnancy and breastfeeding in Part 3 and vaccine-specific chapters in Part 4 for further information.

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Table 1 - Footnote 4

Refer to Contents of immunizing agents authorized for use in Canada for additional information.

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Table 1 - Footnote 5

Refer to vaccine-specific chapters in Part 4 for further information.

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Vaccine administration

Vaccines should be administered to the right person using the correct indication, correct vaccine, correct dose, correct route of administration, correct injection site (if applicable) and correct time (schedule), to optimize vaccine effectiveness and to reduce the risk of local reactions or other adverse events. For information on proper documentation of vaccine administration, refer to Immunization records in Part 1. Table 2 provides an example of a checklist for vaccine administration. Refer to Storage and handling of immunizing agents in Part 1 and vaccine-specific chapters in Part 4 for additional information.

Table 2: Vaccine provider administration check list
Vaccine administration Yes No
  1. Has the vaccine provider washed his or her hands or used an alcohol-based hand sanitizer?
   
  1. Has the patient's immunization history and the vaccine schedule been checked to ensure the appropriate vaccine is being administered at the appropriate time?
   
  1. Has the correct vaccine been selected and expiry date been checked?
   
  1. Has the vaccine been appropriately reconstituted or mixed if necessary?
   
  1. Has the appropriate needle length been selected?
   
  1. Are the dose and method of administration correct?
   
  1. Has the administered vaccine been properly documented?
   

Vaccine preparation

Vaccine inspection and mixing

Before vaccine administration, the vaccine identification label must be checked to ensure selection of the correct vaccine. The expiry date on the vaccine vial and vaccine diluent (if applicable) must be verified to ensure that they have not expired. Vaccines or diluents should not be used beyond their expiration date. Before use, inspect vaccine vials for any irregularities, such as particulate matter, damage or contamination.

Vaccines should be mixed with a careful swirling motion until a uniform suspension is achieved prior to administration. Unless otherwise instructed by the manufacturer, the vaccine should not be shaken before use.

Vaccine providers should adhere to jurisdictional or organizational policies and procedures regarding combining the contents of multi-dose vials. Refer to Storage and handling of immunizing agents in Part 1 for additional information about multi-dose vials.

Vaccine reconstitution

Vaccines should be reconstituted according to the manufacturers' guidelines, using only the diluent provided by the manufacturer for that purpose, and adhering to jurisdictional or organizational policies and procedures. The diluent should be introduced down the side of the vaccine vial and not directly into the vaccine powder, to avoid foaming or potential denaturing of the vaccine protein. The reconstituted vaccine should be mixed with a careful swirling motion until a uniform suspension is achieved prior to administration, unless otherwise instructed by the manufacturer. Once reconstituted, the vaccine should be administered within the time frame specified in the manufacturer's product information. Refer to Storage and handling of immunizing agents in Part 1 for additional information about vaccine reconstitution.

Filling syringes

Vaccine providers should observe strict aseptic technique when reconstituting and drawing vaccine into the syringe. Prior to withdrawal of vaccine into the syringe, the vaccine vial should be uncapped, the stopper wiped with a suitable disinfectant (e.g., isopropyl alcohol) and the stopper allowed to dry.

Refer to Infection prevention and control for additional information.

Pre-loading vaccine in syringes

Ideally, a vaccine should be withdrawn from the vial immediately before use by the vaccine provider who is administering the vaccine. Pre-loading syringes with vaccine is strongly discouraged because of the uncertainty of vaccine stability in syringes, risk of contamination, increased potential for vaccine administration errors, and vaccine wastage. Pre-loading of syringes may be considered in the hospital setting if vaccines are drawn up and labelled in the pharmacy, or in an immunization clinic to facilitate efficient administration of a single vaccine to a large number of people; in these circumstances, the following principles should be followed:

Vaccine providers should adhere to jurisdictional or organizational policies and procedures in regards to pre-loading vaccine in syringes. Refer to Storage and handling of immunizing agents in Part 1 for additional information.

Syringe and needle selection for parenteral vaccines

A separate sterile needle and syringe should be used for each injection. Different vaccines must never be mixed in the same syringe, unless specified by the manufacturer. The use of safety-engineered needles and syringes is preferred and, in many jurisdictions, mandated by law to reduce risk of injury. However, vaccines packaged by the manufacturer in pre-filled syringes should not be transferred to safety-engineered injection devices unless jurisdictional or organizational regulations make this mandatory.

Syringe selection

Use a 1 mL or 3 mL syringe, depending on the volume of the vaccine dose.

Needle selection

Appropriate needle selection is important because the immunizing agent must reach the appropriate tissue site (dermis, subcutaneous tissue or muscle) to optimize the immune response and to reduce the risk of injection site reactions. When considering needle length, select a needle that is long enough to reach the tissue site, but not so long as to hit underlying bone. The use of longer needles for intramuscular (IM) injection of vaccine is associated with less injection site redness and swelling than occurs with shorter needles. When needles are too short to reach muscle, vaccine may be inadvertently injected into more superficial tissue such as dermis and subcutaneous tissue, resulting in increased inflammation, induration or granuloma formation. For IM injections, the needle must be long enough to reach muscle but not involve underlying nerves, blood vessels, or bone; the needle should be inserted as far as possible into the muscle. The selection of the right needle should be based on the route of administration, the vaccine recipient's age and size of muscle mass, and the viscosity of the vaccine or passive immunizing agent. Table 3 provides guidelines for needle selection.

Table 3: Needle selection guidelines
Route of administration Needle gauge Age of vaccine recipient Site of injection Needle length

Intradermal (ID)

26 to 27

All ages

 

1.0 cm

Subcutaneous (SC)
45° angle

25

All ages

< 1 year: anterolateral thigh
≥ 1 year: upper triceps area or anterolateral thigh

1.6 cm
(⅝ inch)

Intramuscular (IM)Table 3 - Footnote 1
90° angle

22 to 25Table 3 - Footnote 2

Newborns (<28 days) and preterm infants

Anterolateral thigh

1.6 cm
(⅝ inch)

Infants
(1 to 12 months)

Anterolateral thigh

2.2 cm to 2.5 cm
(⅞ inch to 1 inch)

Young children
(>12 months to 3 years)

Deltoid muscle

1.6 cm to 2.5 cm (⅝ inch to 1 inch)

Anterolateral thighTable 3 - Footnote 3

2.5 cm to 3.2 cm
(1 inch to 1¼ inch)

Children
(>3 years to 12 years)

Deltoid muscle

1.6 cm to 2.5 cm
(⅝ inch to 1 inch)

Anterolateral thigh

2.5 cm to 3.2 cm
(1 inch to 1¼ inch)

Adolescents
(>12 years to 18 years)

Deltoid muscle

See weight-based recommendations for adolescents and adults below

Anterolateral thigh

2.5 cm to 3.2 cm
(1 inch to 1¼ inch)

Adolescents and adults
(>12 years)

Deltoid muscle

For those weighing <130 lbs (<60kg):
1.6 cm to 2.5 cm (⅝ inch to 1 inch)

Males weighing 130 to 260 lbs (60 to 118kg)
and females weighing 130 to 200 lbs (60 to 90kg):
2.5 cm (1 inch)

Males weighing >260lbs (118kg) and females weighing >200lbs (90kg):
3.8 cm (1½ inch)

Table 3 - Footnote 1

A range of needle lengths are provided as clinical judgment should be used when selecting needle length for IM injections. Consideration should be given to vaccine recipient's weight, gender and age. These recommendations are based on the practice of having the skin stretched flat (between thumb and forefinger) at the time of administration.

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Table 3 - Footnote 2

A larger gauge needle (e.g., 22 gauge) may be required when administering viscous or larger volume products such as immune globulin.

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Table 3 - Footnote 3

The deltoid site is often selected for toddlers and young children as temporary muscle pain post-vaccination in the anterolateral thigh muscle may affect ambulation.

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Filter needles are not recommended for vaccine administration as they may filter out active ingredients such as adjuvants.

Route, site and technique for vaccine administration

Parenteral vaccines

Appropriate site selection for vaccine administration is important to avoid inadvertent injection into a blood vessel or injury to a nerve. Vaccines containing adjuvants must be injected intramuscularly. If a vaccine containing an adjuvant is inadvertently injected subcutaneously or intradermally, increased inflammation, induration or granuloma formation may occur.

Injection of a vaccine into an area where lymphatic circulation may be impaired (e.g. local lymphedema, lymphangioma, axillary lymph node dissection, A-V fistula, upper limb amputation) could theoretically result in an impaired immune response due to impaired vaccine absorption, although there are no data to support this. Consider an alternative injection site if possible. There is no evidence or theoretical rationale for avoiding injection through a tattoo or superficial birthmark.

Active immunizing agents should not be administered into the buttock (gluteal muscle). The gluteal muscle is an acceptable site for administration of Ig when large volumes are administered, and activation of the immune system is not required, but appropriate site selection of the gluteal muscle is necessary to avoid injury to the sciatic nerve.

For additional information about administration of parenteral vaccines to people with bleeding disorders refer to Immunization of persons with chronic diseases in Part 3.

Intramuscular injections

Intramuscular injections (IM) of vaccine are administered into the anterolateral thigh muscle (vastus lateralis) in newborns, preterm infants and infants less than 12 months of age. The anterolateral thigh or the deltoid muscle can be used for toddlers and older children. The deltoid is usually often selected as the injection site in these age groups as temporary muscle pain post-vaccination in the anterolateral thigh muscle may affect ambulation. The deltoid muscle of the arm is the preferred injection site in adolescents and adults (unless the muscle mass is not adequate, in which case the anterolateral thigh can be used). Clinical judgment should be used when selecting needle length for IM injections as consideration should be given to vaccine recipient's weight, gender and age. IM injections should be administered at a 90o angle. The skin should be stretched flat (between thumb and forefinger) at the time of administration.

Large volumes of immune globulin for IM injection (greater than 2 mL for children or greater than 3 to 5 mL for adults, depending on muscle mass) should be divided and injected at 2 or more sites. Currently available human Ig preparations, with the exception of standard intravenous Ig, varicella Ig, CMV Ig, vaccinia Ig and botulism Ig must not be given IV because of the risk of rare anaphylactic reactions.

Subcutaneous injections

For infants younger than 12 months of age, the usual site for subcutaneous (SC) administration of vaccine is the subcutaneous tissue of the anterolateral thigh; if necessary, the upper triceps area of the arm may be used. SC injections for vaccine recipients 12 months of age and older are usually given into the subcutaneous tissue of the upper triceps area of the arm. SC injections should be administered at a 45o angle. Pinching of the skin may be necessary to ensure injection into the subcutaneous tissue.

Intradermal injections

Intradermal (ID) vaccine administration technique is product-specific and should be applied according to the vaccine's product monograph or product leaflet.

The inner forearm is the preferred site for ID injections. The skin should be pulled taut with the non-dominant hand at the time of administration to ensure easy penetration of the needle. ID injections should be administered at a 5° to 15° angle. The needle should be inserted slowly into the dermis until the entire bevel is under the skin without aspirating. The injection should produce a noticeable pale elevation of the skin known as a wheal. A wheal is an area of the skin that is raised like a blister or bubble. The presence of a wheal 6 mm to 10 mm in diameter indicates that the medicine has been administered into the dermis properly. If a wheal does not form, remove the needle and repeat the procedure in preferably a separate anatomic injection site (different limb) or in the same limb but separated by at least 2.5 cm (1 inch).

Multiple parenteral injections

All opportunities to immunize should be used. Giving multiple vaccines at the same clinic visit is encouraged as it helps to ensure that individuals are up-to-date with the vaccines required for their age and risk factors. Practice considerations for multiple injections include the following:

Oral vaccines

Oral vaccines should be administered as directed in the product leaflet. In general, oral vaccines should be given prior to injectable vaccines. If an incomplete dose of an oral vaccine is administered for any reason (e.g., infant spits or regurgitates the vaccine), a replacement dose should not be administered. Rotavirus vaccine can be given by NG or NJ tube. It should be administered and the tube rinsed according to local protocols for administration of oral medications into NG or NJ tubes.

Intranasal vaccine

Live attenuated influenza vaccine (LAIV) is the only vaccine in Canada administered by the intranasal route. LAIV should be administered by a health care provider following the instructions in the product leaflet. If the vaccine recipient sneezes immediately after administration, there is no need to repeat the dose. If significant nasal congestion is present that might impede delivery of LAIV to the nasopharyngeal mucosa, an inactivated vaccine can be administered or LAIV can be deferred until resolution of the illness.

Refer to Contents of immunizing agents authorized for use in Canada in Part 1 for information about the recommended route of administration for specific vaccines and passive immunizing agents authorized for use in Canada.

Techniques to decrease immunization injection pain

Vaccine injections can be a source of distress for individuals of any age, as well as for the immunization provider. If not addressed, the pain and anxiety associated with immunization can increase fear leading to avoidance of future medical procedures and lack of adherence to immunization schedules. It is estimated that up to 25% of adults have needle fears and 10% have needle phobias, defined as a marked and persistent fear that is excessive or unreasonable, cued by the presence of needles or anticipation of vaccination. The majority of people with needle fears develop them in childhood. Efforts to minimize pain can help to promote satisfaction and trust in health care providers and potentially prevent the development of needle fears.

Evidence exists for effective pharmacologic, physical, and psychological interventions to manage pain during immunization. Combining strategies has been shown to improve pain relief.

Refer to Table 4 for a listing of pain management strategies for children by age groups.

Table 4: Immunization pain management strategies, by age groupsTable 4 - Footnote 1
Age group Pain management strategies
All ages
Infants and young children (3 years of age and under)Table 4 - Footnote 2
  • Education of parent/caregiver about pain management before and on the day of immunization
  • Topical anesthetics prior to vaccine injection
  • Presence of parent/caregiver during vaccine injection
  • Breastfeeding during vaccine injection (≤ 2 years of age)
  • If the infant/young child is not breastfed during vaccine injection, a combination of other strategies may be used, such as:
    • Skin-to-skin contact during vaccine injection (≤1 month of age)
    • Holding during vaccine injection or holding and rocking/patting after vaccine injection
    • Administration of a sweet-tasting (sucrose or glucose) solution prior to vaccine injection (≤ 2 years of age)Table 4 - Footnote 3
Children (3 to 12 years)Table 4 - Footnote 2
  • Education of parent/caregiver about pain management before and on the day of immunization
  • Education of individual about pain management for vaccine injection on the day of immunizationTable 4 - Footnote 4
  • Topical anesthetics prior to vaccine injection
  • Presence of parent/caregiver during vaccine injection (≤ 10 years of age)
  • Sitting up during vaccine injection
Adolescents (12 to 17 years)Table 4 - Footnote 2
  • Education of parent/caregiver about pain management before and on the day of immunization
  • Education of individual about pain management for vaccine injection on the day of immunizationTable 4 - Footnote 4
  • Sitting up during vaccine injection
Adults (≥ 18 years)
  • Education of individual about pain management for vaccine injection on the day of immunizationTable 4 - Footnote 4
  • Sitting up during vaccine injection
Table 4 - Footnote 1

The strategies noted in the table are strong recommendations for reducing pain during vaccine injections from Taddio A, McMurtry CM, Shah V et al. (HELPinKIDS&Adults Team) Reducing pain during vaccine injections: clinical practice guideline. CMAJ 2015; 187(13): 975-982. For additional recommendations on pain management strategies, refer to the article.

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Table 4 - Footnote 2

There is some overlap in ages across these categories (i.e., children aged 3 and 12 years are included in two separate categories) owing to the need to balance over-simplification in creating age categories with appropriate guidance, overlap in the underlying literature base as well as substantial differences in developmental trajectories of individual children.

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Table 4 - Footnote 3

If an infant is scheduled to receive a dose of rotavirus vaccine, provide it first as it is sweet-tasting. In this scenario, no additional sweet-tasting solution is required prior to vaccine administration.

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Table 4 - Footnote 4

For example, give information on what to expect (the procedure and how it will feel) as well as suggestions on how to cope.

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Breastfeeding

Mothers should be encouraged to breastfeed their infants before, during, and after the immunization. Breastfeeding during immunization reduces pain and distress through:

Children up to 24 months of age should be breastfed before vaccine administration if a mother chooses not to breastfeed during vaccine injection. Alternatives to breastfeeding such as bottle feeding with expressed breast milk or formula should be considered if a mother chooses not to breastfeed or the infant is normally fed by other methods.

Sweet-tasting solutions

Children up to 24 months of age, who are not breastfed during immunization, may be given a sweet-tasting solution such as sucrose or glucose solution 1 to 2 minutes before vaccine injection. Administration of a sweet-tasting solution in addition to breastfeeding before vaccine injections is not recommended. The analgesic effect of a sweet-tasting solution has been demonstrated to last for up to 10 minutes following administration, and can mitigate vaccine injection pain. A sweet-tasting solution is recommended for the management of painful medical interventions only; it should not be used at home as a comfort measure for infants.

Positioning

Proper positioning can reduce pain and anxiety. Skin-to-skin contact during vaccine injections is recommended for infants up to 1 month of age who are not breastfed during vaccine injection. For children up to 3 years of age, holding is recommended during vaccine injections. If not used during vaccine injections, a combined holding intervention with patting or rocking after vaccine injections is recommended in children up to 3 years of age.

Sitting upright during vaccine injections is recommended for all individuals 3 years of age and older.

Topical local anesthetics

Topical local anesthetics act by inhibiting the generation and transmission of pain impulses across nerve endings located in the dermis. They decrease the pain as the needle penetrates the skin and reduce the underlying muscle spasm, particularly in case of sequential injections. Topical anesthetics are effective in reducing vaccine injection pain and should be applied before vaccine administration.

There is no evidence that the application of a topical local anesthetic poses a risk of decreased immune response to vaccines if the topical anesthetic is used as directed in the product leaflet and for the ages recommended by the manufacturer. Because serious adverse events have been reported following excessive application, children should be observed during and after use of topical anesthetics, as they may be at greater risk than adults for serious adverse events. For additional information refer to Health Canada's advisory Safety information regarding topical anesthetics and serious adverse events - For Health Professionals.

Oral analgesics

Administration of oral analgesics (such as acetaminophen or ibuprofen) to children to reduce pain prior to or at the time of vaccine injection is not recommended, as there is no evidence of a benefit from this intervention.

Injection without aspiration

Aspiration prior to injection of vaccine is not recommended, as there are no large blood vessels at the recommended immunization sites and not aspirating before injection has been demonstrated to reduce pain.

Order of vaccine administration

When administering multiple vaccine injections sequentially, the vaccine that causes the most injection site pain should be injected last.

Techniques to decrease anxiety and fainting

The likelihood of fainting is reduced by measures that lower stress in those awaiting immunization, such as short waiting times, comfortable room temperature, preparation of vaccines out of view of recipients, and privacy during the procedure. To reduce injuries due to fainting, people should be immunized while seated, or if considered at high-risk, while lying down.

Foster a safe environment by educating immunization personnel and vaccinees on avoiding unsafe activities, such as stair climbing or driving immediately after immunization. For example, school immunization programs may wish to institute a pairing policy (two students remain together) so vaccinees are not alone for the first 10 to 15 minutes after leaving the immediate clinic location, in case they faint and fall or begin to experience symptoms of anaphylaxis.

Post-vaccination counselling and observation

Vaccine recipients should be counselled about the reporting and management of common adverse events following immunization. The use of an adhesive bandage to cover an injection site is optional but may be desired to prevent a tiny amount of blood from staining clothing. For treatment of minor adverse reactions such as fever or injection site discomfort that might occur following vaccination, oral analgesics and antipyretics (such as acetaminophen or ibuprofen) can be used. There is no evidence that antipyretics prevent febrile seizures.

Vaccine recipients should be kept under observation for at least 15 minutes after immunization; 30 minutes is a preferred interval when there is a specific concern about a possible vaccine reaction. In low-risk situations, observation can include having vaccine recipients remain within a short distance of the vaccine provider (e.g., within the school when immunization is carried out in that setting) and in the company of another person, able to return immediately for assessment if they feel unwell. Every vaccine provider should be familiar with the signs and symptoms of anaphylaxis and be prepared to act quickly. Refer to Anaphylaxis and other acute reactions following vaccination in Part 2. For information about fainting, anxiety or breath-holding, refer to Anaphylaxis and other acute reactions following vaccination in Part 2.

Vaccine recipients or their caregivers should be advised to notify their vaccine provider or other healthcare provider about any concerns that arise following immunization. The provider can then assess these concerns and, if appropriate, complete an adverse event following immunization (AEFI) report. For information about AEFI reporting, refer to Adverse events following immunization in Part 2.

Infection prevention and control

Vaccine providers should incorporate routine infection control practices into all immunization procedures as follows:

In addition to the recommendations above, the following practices should be observed:

Additional information on infection prevention and control guidelines is available in Routine practices and additional precautions for preventing the transmission of infection in healthcare settings.

Selected references

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