I did a quick search on google and this is the from the first result that I found here
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Background: Catscratch disease (CSD) is a self-limiting infectious disease characterized by edema and pain in the lymph nodes (ie, regional lymphadenopathy, lymphadenitis). Symptoms can vary from mild to severe and may include malaise, anorexia, or both. Approximately 75% of cases occur from September through March. The first description is credited to Henri Parinaud, who referenced the condition in French medical literature in 1889. Dr Robert Debré was the first to recognize the cat as a vector for this disorder and coined the term catscratch disease in 1931.


Pathophysiology: Lymphatic and reticuloendothelial systems are most commonly involved, although constitutional and ocular symptoms are also described.
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They are discussing the disease in people here, but they go on to say that it can be gotten from scratches from critters (not just cats), so maybe they thought Timmy might have gotten it by being scratched....