Dr. Francisco R. Velázquez: Fall is here, and with it the beginning of respiratory illness season

By Francisco R. Velázquez, M.D., S.M., FCAP

The autumnal equinox came and went, and now fall colors adorn the Pacific Northwest landscape. The busy summer season is over, students are back in school, and believe it or not there are already signs of the upcoming seasonal holidays and festivities. These holiday previews seem to start earlier every passing year.

In addition to signaling changing weather patterns, fall also means that an increase in respiratory viral infections is coming. The seasonality and cyclical nature of respiratory viral diseases has been recognized for thousands of years. One of the earliest documented accounts of the seasonality of some viruses can be found in the “Book of Epidemics” written by Hippocrates around 400 BC. The causal relationship of temperature, humidity and human activities have been examined and debated for years.

With colder temperatures and more inclement weather, indoor activities increase, as well as the time that we all spend around each other in close proximity. Although warm, cozy and festive, these activities contribute to the transmission of viruses with familiar names like influenza, and respiratory syncytial virus. Others like adenovirus and rhinovirus, which cause the common cold, can be seen throughout the year. SARS-CoV-2, which causes COVID-19, has not demonstrated an identifiable seasonal pattern, but the same cold-weather behaviors can cause an increase in COVID-19 transmission too.

As we saw last year, we anticipate seeing flu, RSV and COVID-19 infections coincide. Let’s review what we know, and how to best protect our community.

Let’s start with the flu, whose expectant seasonality helps us to predict what transmission will look like. The flu season in the Southern Hemisphere is usually between April and September, giving us an early look at which flu types are circulating, the severity of illness, and the season longevity. What happens in the other half of the world does not mean we will see the exact same pattern, but it does inform the strategy for the upcoming flu season, including the composition of the current flu shot and the potential for severe disease. Flu season in the Northern Hemisphere can start as early as October and extend into April and May. Based on preliminary data from five countries in the Southern Hemisphere, the flu vaccines may have prevented up to 50% of potential hospitalizations. The quadrivalent vaccine for our flu season is available and being actively administered.

RSV season usually starts in September and runs through January. We have already seen an increase in positive tests and cases in the southeast portion of the country. Historically, such regional increases are typical with increased activity moving north and west over the following two or three months. This year we have two therapeutic options which were not available before. Two vaccines have been released this year for people 60 and older. Recommendations will be made individually using shared clinical decision making, which means age, comorbidities, and other variables will be taken into consideration. One of the vaccines has also been approved for pregnant women between 32 and 36 weeks of pregnancy during September through January. This provides up to six months of protection once the baby is born.

In addition, a monoclonal antibody compound can be given to babies under 8 months of age who are entering their first RSV season. Children who are 8 to 19 months old, who are at increased risk for severe disease, and who are entering their second RSV season can also receive this treatment.

Lastly, COVID-19 continues to be present in the environment. Members of the Omicron family, which have been with us for a long time, continue to mutate and become more effective at transmission. Cases around the country have increased over the past few weeks, including here in Spokane County. This fall, a reformulated vaccine was made available, which takes into consideration the newer sublineages. This type of reformulation isn’t new. It happens every year with the flu vaccine as we determine which strains have the highest probability to cause disease.

Given the person-to-person transmission that each of these viruses is known for, it is important to follow a few very simple precautions:

• Know your personal risk for severe disease and the risk for those around you, including family, friends, and co-workers.

• Know the transmission risk in your community so you can plan your activities accordingly – check transmission rates at covid.srhd.org and the Respiratory Illness Dashboard at doh.wa.gov.

• Wash your hands thoroughly and often.

• Properly cover your sneezes and coughs.

• If you feel sick, get tested, stay home, and monitor your symptoms.

• Don’t forget to test and mask as recommended.

• And, very importantly, talk to you provider about what vaccines are important for you, and when to get them.

Generally, I recommend you start thinking about getting your vaccinations after Labor Day and be completed with the process before Halloween. That makes it easy to remember. The best way to prevent these respiratory viruses is by getting the vaccines each year.

Stay safe, stay well and let’s do our best to have great fall and winter seasons.

Francisco R. Velázquez, M.D., S.M., FCAP, is health officer for the Spokane Regional Health District.