COVID-19 pandemic underlines link between health-harming behaviors and communicable diseases

If we are to tackle future pandemics successfully, and reduce their impact on people's health and our global healthcare systems, we need to invest in developing fitter, healthier, more resilient populations that are less likely to become infected with communicable diseases and less likely to develop more severe symptoms if infected.

The recent COVID-19 pandemic has highlighted that individuals with health-harming behaviors such as obesity and smoking, which are more commonly associated with non-communicable diseases (NCDs), are more likely to contract and have poorer outcomes from COVID-19.

A new synthesis of research looking at COVID-19 and a range of different communicable diseases suggests that if we are to prepare for future infectious disease pandemics, then we have to tackle the on-going global health crises relating to obesity, inactivity, smoking and alcohol misuse.

Writing in BMC Public Health Dr. Sophie Harrison and colleagues at the Public Health Collaborating Unit, School of Medical and Health Sciences, Bangor University, and Public Health Wales, combined findings from 53 reviews, which included over 2000 individual pieces of research, on the topic of health-harming behaviors (smoking, alcohol abuse, drug use, obesity, physical inactivity) and their association with different infectious diseases, including influenza, tuberculosis, hepatitis and COVID-19. Findings suggest that individuals with existing health-harming behaviors are also at increased risk of contracting and/ or developing more severe forms of a range of infectious diseases.

The authors believe this to be the first time that a review has brought together studies exploring the impact of behavioral risk factors on a range of communicable diseases.

Dr. Sophie Harrison of Bangor University explained: "Behavioral factors, such as alcohol use, smoking, obesity, and illicit drug use, are well documented to impair the immune system. Impairments to the immune system can make individuals more susceptible to communicable diseases and less able to control or recover from infection, leading to worse outcomes. The use of alcohol or drugs may also reduce the efficacy of treatment for communicable diseases."

Professor Mark Bellis, a co-author of the study said: "We do not know which infectious organism will represent the next major threat to global health. For that reason, we have examined how risks of infection and illness from a range of infectious diseases are affected by so called 'lifestyle' behaviors typically associated with non-communicable diseases such as diabetes and cancer. Our findings suggest that reducing health harming behaviors such as poor diets, smoking and alcohol misuse is likely to improve resilience to different infections and reduce the risks and impacts of known, and potentially unknown, future infectious disease threats."

Natasha Judd of Bangor University added: "Health-harming behaviors are known to cluster in disadvantaged populations, and therefore preventing these behaviors, especially among disadvantaged populations, is likely to play an important role in reducing health inequalities and unequal burden of future pandemics."

Sara Wood, lead author at Public Health Wales added: "With public interest in health increasing over the COVID-19 pandemic, this is a good opportunity for people to consider health-improving steps they can take to help protect themselves from both communicable and non-communicable diseases."