According to an article published by Dr. Richard Atkinson in the journal Mayo Clinic Proceedings, "the growing body of evidence that viruses produce human obesity supports the concept that at least some of the worldwide epidemic of obesity in the past 25 years is due to viral infections."
Dr. Atkinson views the pattern of spread of obesity since 1980 as an epidemic compatible with "infectious origin." Although noting that lack of exercise and food intake were obviously of great importance to this epidemic, he has focused on various animal and human viruses that have been shown to increase obesity. For instance, the SMAN-1, an avian adenovirus from India, is the only animal virus "associated with human obesity."
The clinical implications of this research, if it stands up, would point to development of infection controls. "Ideally," Dr. Atkinson noted, "we could prevent infection and virus-induced obesity with a vaccine for the obesity viruses. Development of a human vaccine will take several years.” .