Lippincott Nursing Pocket Card - November 2023

Recognizing and Managing Adult Viral Infections


About Adult Viral Illnesses

Adult viral illnesses are on the rise in a post-pandemic season. Cases of respiratory syncytial virus (RSV) and influenza have increased with the loosening of COVID mitigation strategies, resuming of social interactions as well as reduced masking and social distancing.  Thus, with the relaxation of these measures, there has been an increase in the number of viral infection cases.


RSV, Influenza, and COVID-19

Respiratory Syncytial Virus (RSV)

  • Although mostly associated with infants and children, RSV can infect and sicken adults as well.
  • Healthy adults infected with RSV have acute respiratory tract infection (RTI) symptoms, such as runny nose and cough.
  • In adults over 50 years of age and those with comorbidities (such as immunocompromised host and advanced age), RSV is often an oversight when patients present with lower RTI symptoms.
  • Mortality in hospitalized adults over 50 years of age is 6-8%.
  • The traditional season for RSV in the United States usually occurs from October to April, with a peak in winter months. Off-season outbreaks may occur with the reduction of mask-wearing and physical distancing.
  • The virus can survive on surfaces for several hours, making handwashing a critical measure to prevent transmission.
  • Risk factors for severe illness include:
    • Cardiopulmonary disease
    • Immunocompromised status
    • History of persistent asthma
    • Residence of altitude greater than 2500 meters elevation
    • Institutionalized individuals
    • Older adults with chronic pulmonary disease or functional disability


  • Infection can occur with influenza A or Influenza B.
  • The traditional season for influenza in the United States is during the winter months, although off-season outbreaks have occurred since COVID mitigation efforts have been relaxed.
  • Older adults and immunocompromised patients may present with milder symptoms and may be afebrile.
  • Symptoms may differ with various strains.
  • Risk factors for severe illness include:
    • Unvaccinated status
    • Underlying pulmonary conditions
    • Underlying central nervous system (CNS) conditions
    • Extremes of age
    • Institutionalized individuals
    • Obesity
    • Immunocompromised status

Coronavirus Disease-2019 (COVID-19)

  • Infection is caused by one of multiple variants of SARS-CoV-2.
  • Although most areas currently do not have strict mitigation policies in place, the virus continues to circulate and mutate into new variants.
  • Vaccines are continuously being upgraded to include as many variants as possible.
  • Different variants have different symptoms and variable incubation periods.
  • Risk factors for severe illness include:
    • Advanced age
    • Asthma and chronic lung disease
    • Cancer
    • Chronic kidney disease
    • Chronic liver disease
    • Diabetes
    • Disabilities
    • Human immunodeficiency virus (HIV)
    • Mental health disorders
    • Obesity
    • Pregnancy
    • Smoking
    • Immunosuppression

The following table summarizes information about each viral illness.  There are many features that are similar among them, making diagnosis based on clinical presentation difficult.
Adult Viral Illnesses
  RSV Influenza COVID-19
Transmission Inoculation of mucous membranes, direct surface contact with droplets to mucous membranes Inoculation of mucous membranes, direct surface contact with droplets to mucous membranes
Inoculation of mucous membranes, direct contact
Incubation 4-6 days 1-4 days Varies depending on variant
  • Cough, rhinorrhea, conjunctivitis, sinusitis, otitis, tracheobronchitis, wheezing
  • Exacerbation of chronic pulmonary diseases 
  • Acute respiratory failure in severe cases
  • Abrupt onset of fever, nonproductive cough, body aches, malaise, nausea, congestion, sore throat, headache
  • Vomiting and diarrhea rare in adults
  • Fever, chills, cough, fatigue, shortness of breath, headache, body aches, congestion, runny nose, loss of taste or smell, vomiting or diarrhea
Testing  Multipathogen PCR, rapid antigen testing, viral culture
Molecular assay, multipathogen PCR, antigen detection assay
Nucleic acid amplification testing (NAAT), antigen testing
Treatment Symptom management: oxygen, bronchodilators, antipyretics
Supportive care: antipyretics, analgesics, hydration; antiviral treatment may be indicated
NIH Guideline for Treatment for Hospitalized Adults
NIH Guideline for Treatment for Non-Hospitalized Adults
Prevention of Severe Illness
Precautions Airborne
Droplet Airborne


With the relaxing of COVID restrictions, reduced mask wearing, and less social distancing, adult viral illnesses are more common than ever. During COVID, there were record low rates of these illnesses, but it is thought that lack of exposure to the viruses due to COVID mitigation may have led to an increase in cases after these measures were lifted and social interaction resumed. These viral illnesses are not an all-inclusive list, but currently are the most common being treated in hospitals (November 2022).
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