Epidemiology study of pediatric primary intussusception aged ≤24 months in pre-rotavirus vaccine era of Jinan, China.

INTRODUCTION: Few studies have reported on the epidemiological characteristics of pediatric primary intussusception in the pre-rotavirus vaccine era of China. It is important to complementary baseline data before rotavirus vaccine introduction in China. This study conduct a retrospective investigation and evaluated the incidence rate, described the epidemiology of pediatric primary intussusception aged ≤24 months. METHODS: We conducted a retrospective investigation in all secondary- and tertiary-hospitals in Jinan. Pediatric primary intussusception inpatients aged ≤24 months were identified depending on ICD-10 discharge code from a total of 63 hospitals from 2011 to 2015. Demographic and clinical information were extracting from the electronic clinical record systems. RESULTS: A total of 575 pediatric primary intussusception inpatients were identified with average annual incidence of 86.5 per 100,000. A significantly higher incidence was observed in males (χ2 = 13.8, P < 0.01), in the ≤12 months old age group (χ2 = 19.5, P < 0.01) and from the urban areas (χ2 = 63.31, P < 0.001). No clear seasonality found. Abdominal pain (80.9%) and vomiting (63.3%) were the most frequently reported. Most intussusception cases occurred in ileo-cecum. Over 92% of intussusception cases were diagnosed by ultrasound alone and 77.4% was successfully treated by air enema. 99.7% were cured. The median time of hospitalization was 2 days (range: 0-35 days). CONCLUSION: This retrospective study provides baseline information of incidence, epidemiologyand clinical characteristics of pediatric primary intussusception in Jinan City during 2011-2016 before the introduction of rotavirus vaccine. It will be important for evaluating safety of rotavirus vaccine if it will be introduced to the routine immunization program in China.

Effects of pidotimod soluble powder and immune enhancement of Newcastle disease vaccine in chickens.

The aims of this study were to prepare pidotimod (PDM) soluble powder and to investigate the immune enhancement properties of PDM in chickens vaccinated with Newcastle disease virus vaccine. In vivo experiment, 360 6-day-old chickens were averagely divided into 6 groups. The chickens, except blank control (BC) group, were vaccinated with Newcastle disease vaccine (NDV). At the same time of the vaccination, the chickens in three PDM groups were given water with PDM for 5days, respectively, with the PDM at low, medium and high concentrations (0.25g/L, 0.5g/L, 1g/L), in control drug group was treated with 0.2ml/PDM dose via drinking water, in vaccination control (VC) and BC group, with equal volume physiological saline, once a day for five successive days. On days 14, 21 and 28 after the vaccination, the growth performance, the lymphocyte proliferation, serum antibody titer, the CD4/CD8 cell ratios and interleukin-2 (IL-2) and interferon-gamma (IFN-γ) were measured. The results showed that PDM at suitable dose could significantly promote growth performance, lymphocyte proliferation, enhance serum antibody titer, CD4/CD8 cell ratios and improve serum IL-2 and IFN-γ concentrations. It indicated that PDM could significantly improve the immune efficacy of Newcastle disease vaccine using doses of 0.5g/L, these results are consistent with the drug acting as an immunopotentiator.