An old foe and the new kid on the block – influenza and SARS-CoV-2 are two potentially deadly viruses that may circulate concurrently this fall and winter. A Baylor College of Medicine expert outlines the precautions to take to prevent contracting and spreading them.
According to Dr. Pedro Piedra, professor of molecular virology and microbiology and of pediatrics at Baylor, it is too early to know what this year’s flu season will be like, but we know that a lot of respiratory viruses that usually circulate during the spring and summer months have quieted down due to social distancing and masking precautions. He said that currently we are not seeing a lot of respiratory activity other than SARS-CoV-2.
But that may change as children and young adults head back into the classroom and college environment. School-aged children have historically played a significant role in the transmission of influenza virus within the household and community, and now we know that SARS-CoV-2 can be efficiently transmitted by children to others in a school-like environment, he said.
In addition to influenza and COVID-19, another virus that could be circulating toward the end of this year and into next is respiratory syncytial virus, or RSV, which has similar symptoms to influenza and SARS-CoV-2, but often does not cause a fever. It’s even possible for someone to contract two viruses at the same time, although this might not be the biggest issue.
“If we see these viruses circulating when SARS-CoV-2 is circulating, my primary concern is that it will be difficult clinically to distinguish one from the other at the beginning of illness until the individual is tested,” Piedra said. “It’s likely going to impact the amount of testing done and the utilization of healthcare. It’s going to complicate matters more.”
The long-term consequences from influenza and RSV can make individuals, especially older adults and those with underlying disease, more susceptible to severe complications if they are subsequently infected with SARS-CoV-2.
This is why staying in good health and taking preventative measures against other viruses is so important, Piedra said.
The best preventative measure against flu would be getting vaccinated against influenza. This year, trivalent and quadrivalent formulations of the vaccine are available:
- Quadrivalent vaccine: contains four strains of the virus, including two influenza B lineages (Yamagata and Victoria) and two influenza A lineages (H1N1 and H3N2)
- Trivalent vaccine: contains three strains of the virus, including one influenza B lineage (Victoria) and two influenza A lineages (H1N1 and H3N2)
Adults over the age of 65 should get either the higher dosage or adjuvanted vaccine as they are more likely to develop an immune response with one of these vaccines. Children under 8 years of age who have never been vaccinated against the flu will need two vaccine doses four weeks apart. The nasal spray vaccine also is available this year for healthy individuals 2 to 49 years old. Remember, it takes two weeks to be protected after all doses of vaccination have been administered.
For those who are nervous to visit the doctor’s office or pharmacy during the pandemic, Piedra reassures that masking and social distancing can mitigate the risk of being infected with SARS-CoV-2. He suggests scheduling a time with the doctor’s office or pharmacist to reduce the risk of exposure to others.
Since there is overlap of symptoms between viruses, knowing which viruses are circulating in their community can help individuals determine which one they might have. If an individual tests positive for influenza and is still within 48 hours of the onset of illness, then antivirals can be prescribed to help lessen the severity of the influenza virus. Antivirals are not used in treating SARS-CoV-2.
“The verdict is out as to what type of season we are going to have for influenza. If we have good social distancing and if more schools are virtual, then that’s one less virus we have to worry about,” Piedra said. “But because we don’t know what the future holds, it’s important to still be vaccinated against the flu.”