>>34
maybe....
"Willis" is devided to popular English Word for Jnanese.　　That is　(will + is)

Will＝ウイル
is ＝イズ
ウイルイズ ⇒ ウイルス（easy to pronounciate)
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Virus ＝ヴィルス　⇒ウイルス（easy to pronounciate)
Then he became a kind of ill cause in Japan.