Saxon Graham lecture takes on COVID-19 and non-communicable disease epidemiology

Taking place in person for the first time since 2019, the School of Public Health and Health Professions’ 15th annual Saxon Graham Lecture this year featured noted UB epidemiology alumnus Zuo-Feng Zhang, PhD ‘91, distinguished professor and chair of the UCLA Fielding School of Public Health’s Department of Epidemiology, who discussed “Challenges and Opportunity of the COVID-19 Pandemic on Non-communicable Disease Epidemiology.”

Zhang, who is also a medical doctor, began by reviewing COVID-19 pandemic statistics – infection rates and in the context of herd immunity – and compared the United States to other countries.

• Of 458.9 million cases worldwide resulting in 6 million deaths, the U.S. counted 81 million infections and 993,000 deaths as of the date of Zhang’s lecture. Worldwide, 6% have had the disease while 400 million are said to have recovered.
• Zhang estimates that 90% of the U.S. population has antibodies from either vaccines or infection.
• Case fatality in the U.S. is currently the highest worldwide at 2.3%. Even as infections and deaths occur daily, Zhang considers every survivor a contributor toward the endemic stage, basing this prospect on his experience with common influenza.
• The U.S. current daily mortality average for COVID-19 is 3.5 per million, or 421,575 annually. We might consider COVID-19 endemic, he said, when daily mortality drops to 0.3 per million (99 deaths per day). Annualized at 36,135 deaths, this would be similar to the number of influenza’s annual deaths – 34,157 in the 2018-19 flu season.

“As higher proportions of people gain immunity protection from vaccines and natural infection, we will see less transmission, much less hospitalization and death, even as the virus continues to circulate at a stable level of infection,” he said.

Stay-at-home policies and masking continue to be protective, Zhang said, citing his own research on risk factors and his paper correlating smoking and air pollutant impacts on the SARS infection.

The risks apply to COVID-19 as well, with non-communicable diseases (NCD) such as cancer, cardiovascular and chronic lung conditions, and diabetes presenting significant severity and mortality rates in those infected with COVID-19. The highest risks are posed by high blood pressure, smoking and air pollution; overlapping factors and co-morbidities, including obesity, smoking and diabetes, further increase risks.

Zhang emphasized that while 80% of those who recover from COVID-19 will develop one or more long-term symptoms, 10 to 15 years of observation would be required to better understand the more than 60 potential “long COVID” symptoms, including the most common: fatigue, headache, “brain fog,” hair loss and shortness of breath.

Understanding the correlations between existing NCD and long-term COVID-19 symptoms, how vaccines will mitigate both infections and long COVID symptoms, and the interrelatedness of all risk factors, will all help to shape strategies for controlling both NCDs and COVID-19, Zhang said.

The Saxon Graham Lectureship honors the life and legacy of a man known as one of the fathers of U.S. chronic disease epidemiology, L. Saxon Graham, a longtime SPHHP professor and chair of the Department of Epidemiology and Environmental Health from 1981 to 1991. Zhang completed his PhD on cancer epidemiology and experimental pathology under Graham’s mentorship.