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Flu, RSV, or COVID-19? Convergence of Three Viruses Creates Risk of Diagnostic Errors

Debra Kane Hill, MBA, RN, Senior Patient Safety Risk Manager, The Doctors Company

With the arrival of colder weather, it is likely that healthcare practitioners will see a spike in influenza (flu) and COVID-19 cases, particularly with the circulation of new Omicron subvariants. Additionally, respiratory syncytial virus (RSV) infection peaked unusually early this season, flooding primary care offices and hospital emergency departments with patients and creating severe shortages of pediatric hospital beds. Public health officials are concerned that these three viruses will converge on communities and create a public health “triple threat.” Healthcare practitioners should prepare now to manage the potential onslaught of respiratory illness.

If there is any good news, it is that the guidance is similar for controlling or minimizing the spread of these three contagious respiratory illnesses. While there is no vaccine for RSV,  vaccines are readily available for COVID-19 and the flu. The bad news is that all three illnesses have similar symptoms, and testing must be performed for each to effectively confirm a correct diagnosis.

Understanding the differences between the flu, RSV, and COVID-19 will help prevent misdiagnosis or delayed diagnosis when patients present with respiratory symptoms. The American Academy of Pediatrics offers information on differential diagnosis between the three viruses, and the CDC provides specific guidance on distinguishing between the flu and COVID. General information about each virus is available from the CDC for practitioners as follows: flu, RSV, and COVID-19. The CDC addresses signs and symptoms, incubation periods, length of time for spreading the viruses, how the viruses spread, individuals at higher risk for severe illness, potential complications, and approved treatments.

Flu Season

During flu season, it is possible that all three of the viruses may spread at the same time. Patients could become infected with one or all of the diseases. To counter this possibility, it is important to continue offering appropriate screening, testing, and vaccinations. Refer to the CDC’s guidance “Frequently Asked Influenza (Flu) Questions: 2022-2023 Season.” Note that both flu and COVID vaccines may be given on the same day if patients are eligible and vaccines follow the appropriate administration schedule.

Patient Safety Strategies

Enhance patient safety by taking the following actions:

Patient Care

  • Follow testing guidelines. Testing is the best method for determining which virus the patient may have while guiding you in decisions about the appropriate treatment.
  • Review the CDC’s “Information for Clinicians on Influenza Virus Testing” for patients with acute respiratory illness symptoms.
  • Encourage your patients (six months and older)—and especially those at high risk—to get an annual flu vaccine.
  • Ensure that the patient’s health record includes standard documentation about the possibility of contracting the flu, RSV, and/or COVID-19—including vaccination informed consent and informed refusal discussions.
  • Adopt a shared decision-making approach for patients at high risk for flu or COVID-19 who are reluctant to get vaccines. Ensure that patients understand the risks of not being vaccinated. Learn more about this process with the Agency for Healthcare Research and Quality’s “The SHARE Approach: Shared Decisionmaking Tools and Training.” The shared decision-making/consent discussion should be well documented in the patient’s record. For additional information, see our articles “Reduce Patient Safety Risks With Vaccinations, Including COVID-19” and “Communicating with COVID-19 Vaccine-Hesitant Patients: Top Tips.”

Office Measures

Patient Education

  • Distribute or display the American Heart Association infographic “Flu Shot 411.” Flu shots reduce the risk of death for people with heart disease.
  • Use other infographics and print resources in your office for RSV, COVID-19, and the flu.
  • Offer a free video in your waiting area to educate patients about getting vaccinated. For an example, see the Mayo Clinic Minute: “Why getting vaccinated for the flu is doubly important this season.”
  • Educate patients to stop the spread of germs:
    • Wash hands frequently.
    • Maintain respiratory etiquette (including masking when possible).
    • Avoid touching eyes, nose, and mouth.
    • Avoid close contact, particularly with those who are sick.
    • Disinfect frequently touched surfaces and objects.
    • Encourage self-isolation if sick.

Community Monitoring

For additional assistance, contact the Department of Patient Safety and Risk Management at (800) 421-2368 or by email.

The guidelines suggested here are not rules, do not constitute legal advice, and do not ensure a successful outcome. The ultimate decision regarding the appropriateness of any treatment must be made by each healthcare provider considering the circumstances of the individual situation and in accordance with the laws of the jurisdiction in which the care is rendered.

J13743 12/22

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