Epidemiologist says the dreaded triple-demic is here, with RSV, flu and Covid-19 cases all rising together

Centers for Disease Control and Prevention map

With national rates of influenza, Covid-19 and respiratory syncytial virus rising together, the "dreaded and much anticipated triple-demic is finally here," epidemiologist Katelyn Jetelina writes in her newsletter, Your Local Epidemiologist. 

RSV is a common virus that usually causes mild, cold-like symptoms. And while most people recover in a week or two, it can be serious for infants and older adults.

The weekly Centers for Disease Control and Prevention influenza-like illness (ILI) surveillance, which includes a tally of patients that go to the doctor with a fever and a cough and/or a sore throat is a general indication of the climate of respiratory health in the United States. The report does not include laboratory-confirmed flu cases. 

The ILI map for the week ending Nov. 26 shows that every state but four have a high or a very high ILI activity level. The CDC puts Kentucky's ILI activity level among the very highest. 

Jetelina writes of the national map, "This level is truly unprecedented; we’ve never seen such high levels of ILI activity at this time of year."

Hospitalizations for respiratory illness are also on the rise. CDC Director Rochelle Walensky said Monday, “Hospitalizations are the highest now than they have been in the past decade.” 

In Kentucky, Covid-19 hospitalizations increased for the second week in a row, taking a big jump in this week's Covid-19 report. Hospitals reported 383 Covid-19 patients Monday morning, an increase of 102 over the prior Monday. That same report showed that nearly 80% of the state's inpatient beds and 81% of its intensive-care beds were occupied. 

Jetelina points out that while ILI surveillance offers an overall view of respiratory illness in the U.S, surveillance for specific diseases also exist, but is imperfect. 

RSV: CDC data shows that RSV continues to rise, although we may be seeing the first signs of peaking on a national level, Jetelina reports. She adds that this is expected given that the positivity rate for RSV tests have already clearly peaked. 

Flu: "Flu cases are increasing and increasing fast," Jetelina writes. She notes that flu hospitalizations are lagged, but increasing. "We expect hospitalizations to continue to rise in weeks to come," she writes. 

Kentucky's latest flu report shows that flu activity in Kentucky continues to rise. In the week ending Nov. 26, the state confirmed 6,378 cases of the flu, up from 3,470 the prior week. So far, the total number of confirmed cases during this flu season is 15,909. 

As Inside Medicine reported, for the first time during the pandemic, flu hospitalizations overtook Covid-19 hospitalizations last week. "This may be a one-off occurrence since Covid-19 hospitalizations are increasing now, too, but it is noteworthy," she writes. 

Jetelina adds that epidemiologist are hopeful that the U.S. flu season will follow what has happened in the Southern Hemisphere (Australia specifically) where there has been a high number of flu cases but a moderate level of hospitalizations. 

Covid-19: "Covid-19 is on the rise across the globe due to the combination of seasonal changes, behaviors changes, and the variant soup. In the U.S., all signs point to the beginning of a wave. For example, SARS-CoV-2 in wastewater is rapidly increasing across all regions," she writes. 

In Kentucky, the state Department for Public Health reported 5,751 new coronavirus cases last week, or an average of 821 per day. That's a nearly 49% jump over the week before, when the state reported 3,866 new cases. But that number that was 43% lower than the week before, indicating that Kentucky continues to be on a rough plateau. 

"One major concern is the rapid rise in hospitalizations among older adults, which has exponentially increased 28% in the past two weeks," Jetelina writes. "This is partly (or wholly) due to abysmal vaccination rates—only 1 in 3 adults over the age of 65+ have their fall Covid-19 booster. A public health failure. Without a recent booster, many people are technically vaccinated but not protected." 

Bottom line, she concludes, "This viral season is like no other. . . .  I’m especially concerned for hospital systems, kids under 5, and adults over the age of 65, as they are at highest risk." 

She adds, "There’s a lot we can do: mask, test before seeing loved ones, get that airflow moving, stay home when you’re sick. The least you can do for a healthy season is get a flu and fall Covid-19 booster. If you haven’t gotten one yet, it’s never too late." 

Jetelina is a California epidemiologist and biostatistician who says she writes the newsletter on Substack as a way to translate public-health science for everyday use, helping people to make evidence-based decisions. She is also a consultant to a number of organizations, including the CDC.