11 avr. 1920 - William Park, MD
Description:
He worked for the New York City Health Department. He helped develop diptheria immunization and was convinced that pfeiffer's bacillus was the cause of 1918's deaths. Vaccines weren't available till october 17th, 1918Ajouté au bande de temps:
Date:
11 avr. 1920
Maintenaint
~ Il y a 105 ans