Prescribing antivirals at the retirement home, and long term care home settings
Purpose
This document outlines local guidance in terms of use of antiviral medications for influenza treatment in individuals at retirement homes, nursing homes, long term care home or other chronic care facilities.
Key messages
- Treatment of antiviral medications can decrease the duration of influenza symptoms and may reduce risk of influenza-related complications, including hospitalization and death.1
- Early empiric antiviral therapy is recommended in adults belonging to priority groups, including (see Box 2 for complete list, also attached as appendix):1
- o Age 65 years or older
- Residents of nursing home or other chronic care facilities
- Chronic conditions (e.g., COPD, congestive heart failure, chronic renal insufficiency, diabetes mellitus, chronic liver disease)
- Having antiviral prescriptions in advance help prevent delays in starting therapy during potential influenza outbreaks for both staff and residents.2
- Antiviral medications are recommended for both suspected and confirmed mild or uncomplicated influenza and severe, complicated influenza.1
- Antivirals work best if administered early (within 48h of symptom onset) but should be used beyond this time period in severely ill individuals (i.e., hospitalized patients, those at risk of severe, complicated illness).
- When influenza is circulating in community, antiviral treatment should be started ASAP; initiation of therapy should not wait for laboratory confirmation of influenza.1
- Antiviral treatment can be discontinued if laboratory testing for influenza is negative.
Recommendations for residents
As per guidance from AMMI (2021-2022), recommendations remain focused on the use of oseltamivir, zanamivir, and amantadine.1
- Oseltamivir (oral): drug of choice for treatment and prophylaxis of influenza (for residents in long-term care homes).
- Zanamivir (inhaled): use in those not responding to oseltamivir, or if suspected/confirmed influenza B infection.
- Not preferred in elderly individuals due to difficulty administering inhaled zanamivir.
- Not recommended in COPD or asthma due to risk of bronchospasms.
- Cannot be administered to intubated patients
- Amantadine: not recommended due to concerns of widespread resistance to influenza A.
In advance to start of influenza season, consider:2
- Prescriptions (with refill orders) for influenza antivirals to have on file for pharmacy/residents, as a standing order in preparation of use during outbreak at facility.
Prophylaxis2,3
- During a laboratory-confirmed influenza outbreak, antiviral prophylaxis should be provided to residents as per Table 1.
- If respiratory symptoms develop in a resident while on prophylaxis, dose should be changed to treatment dose as per Table 1.
Treatment2,3
- Once outbreak has been declared, additional laboratory confirmation of new cases is not required to begin treatment (see Table 1) of residents who meet case definition.
- Ill residents should remain in their rooms for the duration of the antiviral treatment (i.e., total 5 days).
Table 1 (based on recommendations from Association of Medical Microbiology and Infectious Diseases Canada (AMMI)3 and treatment guidance from Public Health Ontario4
|
Antiviral treatment |
Prophylaxis |
---|---|---|
TamifluTM (drug of choice)
|
75 mg PO BID for 5 days |
75 mg PO OD |
RelenzaTM (alternative if Tamiflu resistance suspected)
|
10 mg (2 puffs) INH BID for 5 days (Avoid use in persons with |
10 mg (2 puffs) INH OD
(Avoid use in persons with |
Recommendations for staff
Further details on guidance can be found on Ministry of Health and Long-Term Care and CDC interim guidance on outbreak management. In brief, if outbreak has been declared:
Note: Refer to Table 1 re: prophylaxis and treatment doses for influenza
Immunized staff2,5
- Staff immunized ≥2 weeks (inactivated or live attenuated influenza vaccine) prior to
outbreak declaration are considered immune, and therefore, have no work restrictions, provided they are feeling well.
- Staff immunized <2 weeks with inactivated influenza vaccine, should take antiviral prophylaxis until immunity is reached (2 weeks from vaccination) or until outbreak is declared over, whichever is shorter.
- Staff immunized <2 weeks with live attenuated influenza vaccine, should not receive antiviral treatment or prophylaxis for at least 2 weeks after vaccination, unless medically indicated.
- Antiviral agents may kill the replicating virus from the administered live vaccine. If antivirals are given during the 2 week timeframe after vaccination, revaccination should be done with an inactivated influenza vaccine.
Unimmunized staff2,5
- Unimmunized staff should be offered vaccine and antiviral prophylaxis until immunity is reached (2 weeks from vaccination) or until outbreak is declared over, whichever is shorter.
- If unimmunized staff refuse to be immunized, then antiviral prophylaxis should be taken until outbreak is declared over, while working at outbreak-affected area
- Staff may commence work with residents as soon as they start antiviral prophylaxis
- Staff who choose to be immunized, but refuse antiviral medications, shou ld NOT be permitted to work in outbreak-affected area until 2 weeks has lapsed since vaccination
- Staff who choose not to be immunized and refuse antiviral medications, may be excluded from working in the outbreak-affected area depending on policies from the facility (refer to MOHLTC for details)
Nirmatrelvir/ritonavir (Paxlovid):
- Patients with both influenza virus and SARS-CoV-2 co-infection receiving SARS-CoV-2 antivirals should also receive oseltamivir per the oseltamivir treatment regimen, based on a medical assessment. Drug-drug interactions with co-administration remain uncertain1
- In the setting of a mixed influenza, SARS-CoV-2 outbreak, symptomatic residents should be started on an antiviral treatment regimen as outline above. Should the causative organism be determined to not be influenza, this treatment course should be stopped.1
- If SARS-COV-2 infection is determined to be the causative organism by diagnostic testing, medical assessment and consideration should be given for appropriate antiviral treatment for COVID-19 such as nirmatrelvir/ritonavir (Paxlovid)