John G. Bartlett, MD


July 24, 2014

Editor's Note: This is the fifth installment of the Medscape Awards in Infectious Diseases, a series that honors the greatest achievements in the field of infectious diseases. In this article, John G. Bartlett, MD, Professor Emeritus of Medicine at Johns Hopkins University School of Medicine in Baltimore, Maryland, offers his choice for the most important vaccine developed since 1980.


Vaccines are a remarkably effective preventive strategy in the field of infectious diseases. The power of this weapon (often referred to as the "pediatric vaccines") is illustrated in the Table, which shows Centers for Disease Control and Prevention (CDC) surveillance data for selected vaccine preventable diseases, comparing median annual disease rates before vaccine availability with recently reported results (2011-2014).

Table. Vaccine Efficacy

Vaccine Prevaccine Cases (n) Cases Reported 2011-2013 (n) Reduction (%)
Measles 502,282 288 99.6
Mumps 186,000 404 99.6
Polio 16,316 0 100
Rubella 47,740 4 > 99.6
Diphtheria 206,000 0 100
Pertussis 147,271 48,277 68
Hib 20,000 9 99.2

Hib = Haemophilus influenzae type b. From Centers for Disease Control and Prevention

Eradication and Reemergence

Measles was declared eradicated in 2002, but is now back, with a 20-year high in reported cases (554 cases from January 1 to July 3, 2014). Most cases have occurred in unvaccinated travelers, who then became sources of transmission when exposed to unvaccinated US natives.

Pertussis rates[1] reflect the subpar protection that accompanied the shift to the acellular vaccine, but there is no going back.[1] These data are misleading because pertussis severity is reduced in those who received the acellular vaccine.

Polio has been eliminated in the United States, but the global picture for polio eradication is grim, with the recent surge of cases in affected countries. None of these vaccines are considered for the Medscape Awards, because all were introduced before 1980.

The Candidate Vaccines

The candidates under consideration for the Medscape Award for most important vaccine developed since 1980 are those developed to prevent infections caused by Haemophilus influenzae type b (Hib), Streptococcus pneumoniae, hepatitis B virus (HBV), and human papillomavirus (HPV). Note that influenza vaccines are not considered because, although there is a new version nearly every year, the first was introduced in 1942 and there is no consensus about how well it works or whether it even works at all.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: