Avery and the pneumococcus

I gave a lecture on Streptococcus pneumoniae (pneumococcus) in our global antimicrobial resistance course today. Despite more than a hundred years of work, the pneumococcus remains a major cause of morbidity and mortality worldwide. We have vaccines, we have effective antibiotics (fewer and fewer…), yet pneumococcal infection still kills about a million kids every year.

Here’s something that I do when I want to feel small: I look back at the papers that Oswald Avery published on the topic of the pneumococcus between 1915 and 1946 in the Journal of Experimental Medicine. (Thanks, JEM, for opening up your archive back to the very first issue!). Not only is the paper defining DNA as the transforming substance in there, but nearly everything that we understand about the pneumococcus was done or predicted by Avery. The carrier state, capsular polysaccharide (and the fact that one can diagnose pneumococcal infection by detecting it in the urine), autolysis, hydrogen peroxide production, discovery of C-reactive protein, and how to make a conjugate vaccine: it’s all there. Our best diagnostics and vaccines are still offshoots of his work.

As with any great scientist, he did not work alone, and many others have contributed to advancing the field, but I remain in awe of Avery.




Dochez, A.R., Avery, O.T. (1915). THE OCCURRENCE OF CARRIERS OF DISEASE-PRODUCING TYPES OF PNEUMOCOCCUS . Journal of Experimental Medicine, 22(1), 105-113.