Immunization of patients in health care institutions: Canadian Immunization Guide

# Introduction
In both acute and long-term health care settings, it is important that immunization be part of organized care plans within each department, with clear accountability for program planning, implementation and evaluation. There is good evidence that the use of health care provider reminders and standing orders or medical directives, as well as evaluation of vaccine coverage with feedback to health care providers, improves vaccine uptake. Immunization programs or increased uptake of available vaccines has been associated with decreased antibiotic usage. Antibiotic usage reductions ranged from 5% to 10% in randomized controlled trials to relative reductions of 64% in observational studies.
Recommended vaccination schedules differ among the provinces and territories; therefore, immunization schedule differences may need to be considered when discharging a patient to another jurisdiction. When transferring a patient, information about the patient's immunization status should be provided to the receiving institution.

# Acute care institutions
Admission to hospital as well as visits to outpatient clinics or the emergency department provide important opportunities for health care providers to evaluate immunization status and to offer vaccination to patients of all ages. For patients without regular sources of health care or those followed in specialized clinics, the only opportunities for immunization may be during clinic visits or hospitalization.
In addition to routine practices, further infection control precautions may be indicated when administering live vaccines, such as varicella-containing, rotavirus, or live attenuated influenza virus (LAIV) vaccines in the hospital setting. For example, transmission of an attenuated virus through a rash occurring after immunization with a varicella-containing vaccine, or viral shedding following rotavirus vaccination could pose a risk to severely immunocompromised patients. Similarly, health care providers and other close contacts of severely immunocompromised patients should avoid contact with these patients for at least two weeks following vaccination with LAIV due to a theoretical risk of transmission. Consultation with the hospital's infection control experts is advised. Live vaccines are generally not administered to immunocompromised patients; refer to  in Part 3 for information about vaccination of immunocompromised people.
Protocols for reporting adverse events following immunization should be in place in acute care institutions. Patients may be admitted to hospital for a serious adverse event following immunization, or patients who receive a vaccine in hospital, may experience an adverse event. Any adverse event following immunization that results in hospital admission or prolongs an existing hospitalization is considered a serious adverse event and should be reported without delay. Refer to  in Part 2 for additional information about reporting adverse events following immunization.

## Pregnant women
The immunization status of any pregnant woman admitted to hospital should be assessed and arrangements should be made to optimize her immunization status. Refer to  in Part 3 for additional information.

## Newborns and infants
Newborns of hepatitis B (HB) infected mothers should receive post-exposure prophylaxis with HB vaccine and HB immune globulin within 12 hours of birth. As well, administration of the first dose of HB vaccine to other newborns at high risk of exposure to HB virus may be considered before discharge. Refer to  in Part 4 for additional information.
Neonatal intensive care units (NICU) should have immunization programs in place for infants who remain in the NICU for 2 months or longer. Refer to  in Part 1 and  in Part 3 for additional information.
Hospitalized infants who qualify for the anti-respiratory syncytial virus monoclonal antibody should receive the first dose at the onset of the RSV season. Qualifying infants who are discharged from hospital during the RSV season should receive their first dose before discharge home if possible. Refer to  chapter in part 4 for more information.

## Post-partum women and other close contacts of newborns
Post-partum, women susceptible to pertussis, rubella or varicella should receive the relevant vaccine before discharge. Arrangements should be made for varicella-susceptible women to receive a second dose of univalent varicella vaccine at least 6 weeks after the first dose. During influenza season, women who did not receive influenza vaccination during pregnancy should also receive influenza vaccine before discharge. Arrangements should be made for household and other close contacts who anticipate having regular contact with the infant to optimize their immunization status. Refer to  in Part 1 for additional information.

## Children and adolescents
Hospitalization may be an ideal opportunity to ensure catch up of routine childhood immunizations. Recommendations may need to be modified depending on the underlying condition leading to hospitalization. Refer to  in Part 3 for additional information regarding children and adolescents who may be hospitalized with immunodeficiency disorders, or undergoing chemotherapy for malignant hematologic disorders. Refer to  in Part 3 for additional information about hospitalized children and adolescents who have chronic conditions.

## Adults
There is an increasing number of vaccines recommended for adults; refer to  in Part 3 for additional information. Despite the growing list of recommended adult immunizations, young and middle-aged adults, especially men, tend to have fewer contacts with the health care system than either children or the elderly; therefore, opportunistic immunization of adults during hospitalization is very important.
Many immunosuppressive or chronic disorders are associated with increased susceptibility to complications of vaccine preventable diseases in adults. Refer to  in Part 3 for additional information on adults who may be hospitalized with HIV or other immunodeficiency disorders. Refer to  in Part 3 for additional information on hospitalized adults who have chronic conditions.

## The elderly
The admission of elderly patients to hospital is an opportunity to optimize their immunization status. Effective programs to vaccinate elderly patients before discharge or while attending a clinic will guarantee that they do not miss influenza immunization in the community during the limited influenza vaccination period. It is also a useful time to assess whether tetanus and diphtheria toxoid-containing (Td) or Tdap, pneumococcal, and herpes zoster (shingles) vaccines are needed. Refer to  in Part 3 for additional information on patients with chronic conditions.

# Long term care institutions
Residents of long-term care facilities, including children, should receive all routine immunizations, as appropriate for their age and risk status. The following vaccines are particularly important to consider: influenza, pneumococcal, and herpes zoster (for residents 50 years of age and older). Td vaccine is recommended every 10 years for adults. Immunization with Td vaccine provides an opportunity to immunize previously unimmunized or under-immunized individuals against polio or pertussis.
Annual seasonal influenza immunization is essential for adults of any age residing in a nursing home, chronic care, or continuing care facility. Programs and strategies should be implemented to ensure that annual influenza immunization occurs. Residents in long-term care facilities that have standing order programs for influenza are more likely to be immunized. Patients and their surrogate decision makers should be advised of the facility's immunization policy on admission and every effort made to obtain informed consent before the influenza season.