J Exp Med. 1918 Feb 1;27(2):305-8.
1
First Medical Clinic of the Imperial University in Kyushu, Fukuoka, Japan.
QUOTE- "The spirochetes disappear almost completely from the organs during the convalescent stage of Well's disease, even when no serum has been administered. The only organ to be excepted is again the kidney, but no comparison between .serum-treated and non-serum-treated cases should be made in this respect, for spirochetes are found numerously in the kidneys even with serum treatment."
Link Here- https://www.ncbi.nlm.nih.gov/pubmed/19868206