Answer:
Stress influence T cells levels, which act as suppressors of the immune system.
Explanation:
According to the National Institutes of Health (NIH), the relationship between stress and illness is really complex, because sometimes stress can act as a booster, improving the immune system, and also can cause a negative effect on the immune system.
Either way, it's being proved that stress affects the immune system, whereas negatively or positively. When the stress is chronical, the immune system is affected negatively, this means that those people will get sick very easily, getting physical or psychological illness.
Specifically, stress influence T cells levels, which act as suppressors of the immune system. So, this suppression is what increases the posibilities of viral infections, that's why chronical stress is so harmful.
