Iowa State University Veterinarian Records, RS 22/6/0/9, University Archives, Special Collections Department, Iowa State University, http://www.add.lib.iastate.edu/spcl/arch/rgrp/22-6-0-9.html
The leptospiroses are infectious and contagious diseases of wild and domestic mammals. Nearly 80 serotypes or species of Leptospira have been identified throughout the world as being responsible for one form or another of leptospirosis. There are probably 8 or 10 serotypes currently recognized in the United States. There is little doubt that in time more will be found in our domestic animal populations.
Morse, Erskine V.
"What You Should Know About Leptospirosis,"
Iowa State University Veterinarian: Vol. 21
, Article 1.
Available at: https://lib.dr.iastate.edu/iowastate_veterinarian/vol21/iss2/1