CRP is an acute phase protein produced by the liver and is a sensitive marker for the inflammatory response. It did not directly related to viral load [17] . However, CRP continuously increased in the initial stages of infection for both the patients with severe and those with moderate H1N1. The CRP of patients with severe H1N1 took longer to return to normal, which might be the result of underlying disease. Each lymphocyte subgroup has made correlatively analyzed with CRP and the results show no significant correlations.