Isolation paradox: Isolating will help you be less susceptible to illness. Isolation is known to cause higher levels of loneliness, depression, fear, anxiety and weaker immune system increasing susceptibility to illness.
It's not really a paradox because it's understood. Isolation signals to your body that you are being excluded from your tribe or low on the social ladder, which means your world is now more threatening than it used to be, so you need to use more energy to be hyper-vigilant and responsive to stressors.
Social status alters immune regulation and response to infection in macaques