Last fall, California experienced a surge in cases of respiratory viral illness—including but not limited to SARS-CoV-2, influenza, and respiratory syncytial virus (RSV)—that strained health care facilities statewide. Recently there has been a nationwide rise in SARS-CoV-2 cases and hospitalizations, and indications that RSV is rising in the southeastern states.
While local influenza and RSV transmission remain low at this time, and SARS-CoV-2 hospitalizations may be plateauing, seasonal activity of those viruses is expected to increase in the coming weeks to months.
The following information for healthcare providers offers disease-specific clinical guidance in anticipation of respiratory virus season. For more information about health care facility planning and response, healthcare administrators may also refer to the AFL Guidance for Response to Anticipated Surges in Respiratory Virus Transmission.
Immunizations for COVID-19, influenza, RSV and pneumococcal disease are recommended for eligible persons this fall. In general, healthcare providers should follow CDC recommendations, and should encourage patients to receive new or updated doses of respiratory virus immunizations this fall. Beginning in October, healthcare providers may view the CDPH Influenza, RSV, and Other Respiratory Viruses Surveillance Weekly Report for statewide respiratory virus activity.
Healthcare providers may continue to track California COVID-19 data to see recent trends in disease activity. Healthcare providers should encourage patients to test and vaccinate for COVID-19. In case of infection, isolation and early therapeutic treatment is recommended.
Vaccination: Everyone 6 months and older (especially health care staff and high-risk groups) should stay up to date on COVID-19 vaccines. More vaccine resources may be found at the CDPH Vaccine site.
Antibody pre-exposure prophylaxis with cilgavimab plus tixagevimab (Evusheld) is no longer indicated because it is unlikely to be active against most (>90%) currently-circulating United States SARS-CoV-2 variants.
Therapeutics: Treatment as soon as possible (ideally <48 hours from symptom onset) with COVID-19-specific agents decreases risk of serious illness, hospitalization, and death. Healthcare providers are recommended to evaluate any symptomatic patient who tests positive for COVID-19 for treatment within 24 hours of seeking care to reduce the risk of hospitalization and death. The CDPH COVID-19 Treatments webpage contains more information about therapeutic treatment.
Healthcare providers may access CDC and CDPH influenza activity and surveillance data. CDPH urges healthcare providers to prepare for increases in seasonal influenza activity even while influenza activity remains low through:
Vaccination: Everyone 6 months and older (including health care staff) should receive a seasonal influenza vaccine. The 2023-2024 influenza vaccines are available now, and for most persons, vaccination should ideally be offered during September or October. However, vaccination should continue after October and throughout the season as long as influenza is circulating, and the vaccine is available.
Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection.
Adults 65 years and older should preferentially receive any one of the following: higher dose, recombinant, or adjuvanted flu vaccines. If none of these three vaccines is available at an opportunity for vaccine administration, then any other age-appropriate influenza vaccine should be used.
New: Additional safety measures are no longer recommended for flu vaccination of persons with egg allergy beyond those recommended for receipt of any vaccine.
Therapeutics: Influenza antiviral treatment is recommended as soon as possible (ideally <48 hours from symptom onset) for any patient with suspected or confirmed influenza who is hospitalized; has severe, complicated, or progressive illness; or is at higher risk for influenza complications. The CDC has issued prioritization guidance in the event of influenza antiviral shortages.
Respiratory Syncytial Virus (RSV)
RSV poses the greatest risk for infants and older adults, especially older adults with chronic medical conditions. RSV activity is currently low in California. More information and resources on RSV may be found at the CDPH RSV site. The following actions are recommended for RSV prevention:
Vaccination for adults:
Vaccination for pregnant persons:
Preventive Monoclonal Antibody Products (Passive Immunization) for Infants and Young Children: Nirsevimab (Beyfortus), a new long-acting monoclonal antibody product, is recommended for prevention of severe RSV lower respiratory tract disease in infants and young children. Nirsevimab can provide protection for at least 5 months (the average length of one RSV season), and only one dose is recommended for an RSV season. Nirsevimab should be available in October 2023. Following pre-COVID-19 pandemic patterns, nirsevimab could be administered from October through the end of March. In accordance with general best practices for immunization, simultaneous administration with age-appropriate vaccines is recommended:
All infants younger than 8 months who are born during – or entering – their first RSV season should receive one dose of nirsevimab. Infants born shortly before or during the RSV season should receive nirsevimab within 1 week of birth. Nirsevimab administration can occur during the birth hospitalization or in the outpatient setting.
Children between the ages of 8 and 19 months who are at increased risk of severe RSV disease are recommended to receive one dose of nirsevimab at the start of their second RSV season. Palivizumab (Synagis) is another monoclonal antibody product that may be used for eligible high-risk infants and children if nirsevimab is not available.
Either a maternal vaccination or a monoclonal antibody is recommended to protect infants against severe RSV disease, but administration of both is not needed for most infants.
Pneumococcal disease is any type of illness caused by Streptococcus pneumoniae bacteria. Some studies have shown an association between increased risk of developing invasive pneumococcal disease and influenza or RSV infection. To prevent pneumococcal disease, CDC recommends pneumococcal vaccination for all adults who are at increased risk for pneumococcal disease, either because of their age (aged 65 years or older) or having certain medical conditions or other risk factors. Routine pneumococcal vaccination is also recommended for all infants and young children.
Infection Control Measures
During periods of increased transmission of respiratory viruses and in the event of a facility outbreak, healthcare providers facilities should consider implementing source control masking policies as described in CDPH's Guidance for Face Coverings as Source Control in Healthcare Settings and in accordance with their local health department recommendations or requirements.
Providers working in hospitals and long-term healthcare facilities (including skilled nursing facilities) should immediately test patients and residents with signs or symptoms potentially consistent with respiratory infection, and promptly isolate in accordance with CDC healthcare infection control guidance: CDC 2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings and CDC Interim Infection Prevention and Control Recommendations for Healthcare Personnel During the Coronavirus Disease 2019 (COVID-19) Pandemic.
Healthcare providers working in licensed healthcare facilities who test positive for COVID-19 should follow return-to-work policy as outlined in the AFL-21-08. For more information on infection control measures in Skilled Nursing Facilities, healthcare providers may visit the CDPH Recommendations for the Prevention and Control of Influenza in CA SNFs during the COVID-19 Pandemic.
Note on diagnostic testing to guide treatment and clinical management
Diagnostic testing can distinguish among viruses that do and do not have antiviral therapies and rationalize their use to reduce illness duration and severity while minimizing unintended consequences.
Diagnostic testing should be considered for patients with suspected respiratory virus infections, those with factors placing persons at high risk for severe outcomes from influenza and COVID-19, and those with severe or progressive illness.
Molecular assays are recommended when testing for RSV, influenza, SARS-CoV-2 in hospitalized patients, and other respiratory viruses should be considered since concomitant infections can cause severe illness. Antigen testing is recommended for non-hospitalized patients. Information to assist healthcare providers about when to consider respiratory virus testing is available at Information for Clinicians on Influenza Virus Testing, Respiratory Syncytial Virus for Healthcare Professionals, and COVID-19 Testing: What You Need to Know.
Surge Measures for Hospitals
Healthcare providers at all hospitals, especially those experiencing a surge, should follow the recommendations listed in the AFL Guidance for Response to Anticipated Surges in Respiratory Virus Transmission.