Context
I live in an Eastern European country within the EU where COVID-19 has created relatively few victims due to the lock-down being put in place quite quickly in the spring. However, as the autumn started the number of cases grew exponentially and the victims as well (the highest mortality rate due to COVID in EU). This is due to some people not being compliant (i.e. wearing masks) and poor hospital infrastructure.
What is worse is that in the last weeks the hospitals have become full and many people cannot be treated anymore (COVID and non-COVID patients).
For several months now, I have been periodically discussing with my brother and my father, and each time I kindly ask them to take care and respect the COVID-19 related restrictions. However, they are telling me that COVID-19 is not that serious (some kind of flu) and are not reducing social interactions.
My father in particular believes that COVID diagnostic is abused and that not that many people dying because of it (this is also due to media stressing out the comorbidities of the most notorious cases). He also avoids wearing a mask whenever possible (the law requires to wear inside and in "crowded" places only, but this is not seriously enforced). One such example was when he had a trip by train and multiple passengers agreed not to wear a mask.
Quite recently they have also sent some pictures about a so-called "miracle" medicine that can help you if you get infected with SARS-COV2. I have told them that this is clearly not a real medicine and the best way to protect yourself before having a vaccine is by drastically reducing physical contact with other people and wearing a mask. This is perfectly feasible for them (100% remote work/retirement).
I have also asked my aunt (retired biochemistry teacher) and my cousin (researcher that worked in all biosafety levels) to talk to them and provide more in-depth explanations. Their feedback is that they did not manage to convince my father about the seriousness of the coronavirus.
The issue
I am very tolerant of people having different opinions of my own (even if such opinions seem absurd to me), but the issue appeared when they reproached me for not paying visits anymore. I said that during this period it is strongly recommended to avoid all unnecessary visits/trips.
Since both my father (65+ and unknown medical issues because he didn't pay a visit to any doctor in years) and my wife (has some respiratory issues) have a higher chance of complication in case of getting sick with this coronavirus, I think it is especially important to sacrifice visiting in order to gain medical safety.
The relationship with my father and brother was never very close, but I do not want to completely ruin it. It has become clear that all my rational arguments are in vain.
So, my question is how to politely enforce to my relatives my will of limiting physical meetings in these uncertain times? My current strategy is to avoid any direct contact (only phone discussions), but I am not sure that this is the best option since SARS-COV2 is not going to leave any time soon.