January 25, 2024 – Amid the current wave of respiratory virus cases in the winter, the flu (Type A and B) has the highest number of emergency room visits, closely followed by COVID-19, thanks to the JN.1 variant, and Respiratory Syncytial Virus (RSV). How challenging is it for doctors to differentiate, diagnose, and treat COVID-19, RSV, and influenza, given their similarities and differences in symptoms?
While these three respiratory viruses often present similar symptoms, according to Cyrus Munguti, MD, Assistant Professor of Medicine at KU Medical Center and hospitalist at Wesley Medical Center in Wichita, Kansas, patients with COVID-19 often experience more fever, dry cough, and breathing difficulties.
„COVID-19 patients tend to have respiratory distress due to Alveolar involvement, leading to inflammation and fluid accumulation in the lungs, ultimately resulting in low to no oxygen,“ said Munguti. „When we check their vital functions, COVID patients tend to have hypoxemia [meaning saturations are less than 88% or 90% depending on the guidelines you follow].“
Patients with RSV and influenza tend to have more upper respiratory symptoms, such as a runny nose and sneezing, which can later develop into upper airway cough, said Munguti. Unlike COVID-19, patients with RSV and influenza often do not experience hypoxemia unless they progress to a severe illness.
All three viruses can cause inflammation of the respiratory tract. Additionally, bacteria residing in these airways could lead to secondary bacterial infections in the upper and lower airways, which could result in pneumonia, said Munguti.
According to Panagis Galiatsatos, MD, Pulmonologist and Associate Professor at Johns Hopkins Medicine, COVID-19 variants have evolved over the years, making it increasingly difficult to distinguish COVID-19 symptoms from those of RSV and influenza. „With the COVID-19 Omicron family, their abilities resemble those that influenza and RSV have achieved over the years, penetrating the airways more aggressively,“ said Galiatsatos.
Galiatsatos emphasized the importance of understanding that diagnosing these illnesses based solely on symptoms can be inconsistent. Objective tests, either at home or in a laboratory, are preferred due to the manifestation of the illness’s dependence on the host factors the virus enters, according to Galiatsatos. For example, virus symptoms may look different in a patient with asthma than in someone with a heart condition.
According to Stan Spinner, MD, Chief Medical Officer at Texas Children’s Pediatrics and Urgent Care, testing and treatment are crucial and can be very accurate in times when respiratory viruses thrive, as children are among the most vulnerable to severe respiratory illnesses. „When individuals are tested for any of these diseases while the prevalence in the community is low, we tend to see false positive results,“ said Spinner.
Texas Children’s Pediatrics and Urgent Care’s 12 locations offer COVID-19 and influenza antigen tests with results available in approximately 10 minutes. RSV tests, on the other hand, are limited to about half of Texas Children’s Pediatrics locations and none of the urgent care facilities, as the test can only be performed by a nasal swab administered by a physician. With no specific treatment or therapy for RSV, the benefits of RSV tests may be limited, often leaving parents frustrated about the next steps post-diagnosis.
„There are a number of respiratory viruses that can produce symptoms similar to RSV, and some of these viruses can even lead to the same side effects as the RSV virus,“ said Galiatsatos. „This is why our doctors need to help parents understand this and provide them with clues on when to seek medical attention for worsening symptoms.“
Spinner added that there are two new RSV vaccines available for specific patient groups. One is an RSV vaccine for infants under 8 months, although its availability is limited. There is also an RSV vaccine for pregnant women (between the 32nd and 36th week of pregnancy), which has proven effective in protecting against RSV infections in newborns up to 6 months old.
Doctors should continue to carefully advise their patients that vaccinations against COVID-19 and influenza play a key role in protecting their families during times of severe respiratory infections.
„These vaccines are extremely safe, and while they may not always prevent an infection, they are highly effective in preventing more serious outcomes like hospitalization or death.“