Bear in mind that at that time TB was considered highly infectious and that is one reason why most 'ordinary' sufferers were sent to sanatoria for treatment.
In fact, it's rather more complicated than that. The bacillus spreads quite easily, but a person in good physical health with a strong immune system will develop antibodies without developing 'active TB'. There was quite a lot of TB in earlier generations of my family, and I have the antibodies, but never a sign of actual TB.
My father's much older half-brother (over 20 years between them), got TB in the 1930s and died from it aged 26. One of the concerns was apparently that he was likely to infect my father ands his sister (aged 6 and 4). So not surprising that the rest of the family stayed away from poor Georgi.
Ann