In a similar study, among 203 HPIV-positive patients (aged 1 to 71 months) with LRTI in China, a total of 32 (15.8%) had an underlying disease, 21 patients were preterm and 18 patients needed oxygen support, 47 patients had leukocytosis, and 39 patients had increased CRP and ESR [27]. Here, CRP is linked to Increased total leukocyte count.