IL6 and streptococcal pneumonia: Interestingly, studies focusing on inflammatory markers in order to discriminate between viral and bacterial respiratory tract infections, found an increase in IL-6 and procalcitonin in lower respiratory infections with bacteremia, and an overall tendency to higher levels of IL-1β, TNFα, IL-10, and IL-1ra in case of streptococcal pneumonia compared to influenza virus, RSV, and human metapneumovirus [49].