Vaccination against infectious diseases is perhaps the most important reason why millions of additional persons do not succumb with morbidity and mortality from viral and bacterial infections in the modern world. Vaccines are most effective when they are administered with sufficient distribution and frequency to protect as many people as possible.
In the July 23, 2009 issue of the New England Journal of Medicine (N Engl J Med 2009;361:335-44, there appeared an article reporting a study by Dipika Sur, MD and colleagues entitled “A Cluster-Randomized Effectiveness Trial of Vi Typhoid Vaccine in India.” The premise of the study was that typhoid fever, caused by infection with the bacteria Salmonella enterica serotype typhi (S. typhi), causes up to 600,00 deaths per year, mostly in developing countries. Injectable Vi polysaccharide vaccine has up to this time been used in a limited fashion in public health programs, and there have been unanswered questions about its effectiveness in children (ages 2 to 5 years) and in particular its use to cause “herd” immunity (e.g., if it is given to a large population living in close proximity, will it promote immunity in the nonimmunized “herd” of people). Read more »
This post, Vi Typhoid Vaccine: Safe And Effective For Young Children, was originally published on Healthine.com by Paul Auerbach, M.D..