proper protection for medical caregiver in

As I have begun my research, I wish to raise a few concerns for your consideration and guidance.

The entire area of preventive medicine, which we might define as "shmirat haguf", and would include proper diet, sleep, , exercise, as well as annual visits to the doctor, inoculation's ,immunizations etc., while listed in the Rambam, De'ot 3-4, do not appear in the regular ShulchanAruch — only Shuchan Aruch HaRav & Kitzur. Why? Does this mean that the entire area of preventive medicine and health maintenance is only a " r'shut," albeit a most critical one? If one does not maintain his health, is he violating (m'vatel) any mitzvat Aseh? (It seems from the Poskim that Rapo Y'rapeh pertains exclusively to permit the doctor to practice,V'nishmartam & V'chai bahem apparently relate to avoid placing oneself directly in a spiritual or physical danger — but not ongoing health maintenance). Indeed, the Rambam in De'ot 3:3 and 4:1 states that maintaining proper health is critical to proper avodat Hashem and Torah study, implying, perhaps, that not maintaining one's health is a kind of bitul Torah.

According to halacha, would a caregiver who enters an ICU and treats a vulnerable, high-risk patient without being properly immunized or not wearing gowns, gloves, or PPE, be considered a potential " mazik ( hezek sheino nikar)?

I look forward to hearing from you. Shabbat shalom & Chodesh Tov!

Rabbi S