Not CLL related, but for those that have pet cats, something to consider given your low immunity with CLL.
"An estimated 22.5% of the U.S. population aged 12 and older has been infected with toxoplasmosis, which is caused by the parasite Toxoplasma gondii (T. gondii). Though cats are the target hosts of T. gondii, any vertebrate can be infected and serve as an intermediate host.
Humans can become infected by coming in contact with infected cats, which shed them in microscopic oocyte form through their waste. It is estimated that 60 million Americans are latently infected with toxoplasmosis, but most people don't show obvious symptoms because they have healthy immune systems. (my emphasis)
A growing body of research suggests the parasite should be considered more of a threat than it is, especially in the realm of mental health. The link between T. gondii and schizophrenia, in particular, has been well established.
...a study released last year suggested the parasite could be involved in one-fifth of schizophrenia cases."
Perhaps a good excuse to have someone else handle the kitty litter tray, or at least wash your hands very well and consider wearing a mask when disposing of the kitty litter.