COVID-19 and the flu are similar in some ways, but are caused by different viruses. Both flu and COVID-19 are spread from person-to-person and can cause varying illness from mild to severe. They also share some symptoms, including:
- Fever or feeling feverish/chills
- Shortness of breath or difficulty breathing
- Sore throat
- Runny or stuffy nose
- Muscle pain or body aches
- Vomiting and diarrhea (more common in children than adults)
The risk of dual diagnosis
“Although there is no clinical evidence so far to suggest that one viral infection, such as influenza, increases susceptibility of being infected by another virus, such as the novel coronavirus that causes COVID-19, it is plausible to suspect that people can be infected by both at the same time,” says Dr. Hai Shao, a board-certified infectious disease specialist affiliated with Sharp Chula Vista Medical Center. “The cell tropism, which are the cells and tissues in your body that support growth of a particular virus or bacteria, and cell surface receptors that induce changes in cell activity are different for each virus.”
Even more concerning, according to Dr. Shao, is that both viruses target and damage the respiratory tract, primarily while stimulating a robust immune response. The risk of having more severe symptoms and severe complications caused by dual infection, such as acute respiratory distress syndrome (ARDS), multi-organ system failure, or sepsis and subsequent bacterial pneumonia, is conceivably higher.
Other common respiratory symptoms — nasal congestion, runny nose, sore throat and productive cough — might also be increased in severity. And the duration of the symptoms, both mild and severe, could be longer.
The upside of flu season during the pandemic
The good news is that the precautions we have been taking for several months to decrease the spread of COVID-19 — hand-washing, wearing face coverings and social distancing — can also decrease the risk of getting the flu. This is because both viruses spread and transmit via respiratory droplets when people who are infected breathe, speak, cough and sneeze.
“Current public health measures would significantly decrease the risk of viral transmission for other common cold viruses as well as influenza,” Dr. Shao says. “It is widely predicted that if people are following guidance of public safety for COVID-19 prevention, we could have a much milder season for influenza this year.”
In addition to preventive steps to slow transmission of both illnesses, Dr. Shao and colleagues stress that the flu shot and vaccination against COVID-19 — when available — is still pivotal to achieve herd immunity and significantly decrease both infections in the community.
“People age 6 months and older should get the flu vaccine as directed by their health care providers,” Dr. Shao says. “And once a scientifically proven, safe and effective vaccine for COVID-19 is available, we should get vaccinated as soon as possible.”
For the news media: To speak with Dr. Shao for an upcoming story, please contact Erica Carlson at email@example.com.