RESUMO
Objective@#To compare the safety and immunogenicity of two different sequential schedules of inactivated poliomyelitis vaccine made from Sabin strain (sIPV) followed by typeⅠ+Ⅲ bivalent oral poliovirus vaccine (bOPV) in Drug Candy (DC) form or liquid dosage form).@*Methods@#This randomized, blinded, single center, parallel-group controlled trial was done from September 2015 to June 2016 in Liuzhou, Guangxi province. Healthy infants aged ≥2 months were eligible for enrollment and divided into 1sIPV+2bOPV or 2sIPV+1bOPV sequential schedules. According to the bOPV dosage form each sequential schedules, the subjects again were divided into drug candy(DC) form or liquid dosage form group, being 1sIPV+bOPV (DC)/1sIPV+2bOPV(liquid)/2sIPV+1bOPV(DC)/2sIPV+1bOPV(liquid). According to 0, 28, 56 d immunization schedule, Each group were given 3 doses. We recorded adverse events during the clinical trial (399 participants who receive at least one dose). 28 days post-Dose 3, we receive a total of 350 blood samples (excluding the quitters or subjects against trial plan), using cell culture trace against polio virus neutralization test Ⅰ, Ⅱ, Ⅲ neutralizing antibody (GMT), calculating the antibody positive rate.PolioⅠ,Ⅱand Ⅲ antibody titers were assessed by virus-neutralizing antibody assay and the seroconversion (4-fold increase in titer) from pre-Dose 1 to 28 days post-Dose 3 was calculated (total 350 samples) .@*Results@#During the vaccination, the incidence of AEs in 1sIPV+2bOPV(DC), 1sIPV+2bOPV (liquid), 2sIPV+1bOPV(DC), 2sIPV+1bOPV (liquid) group were 79%, 76%, 80% and 74% (χ2=1.23, P=0.747) , respectively. The severe AEs in groups were 6%, 5%, 6% and 4% (χ2=0.57, P=0.903) , respectively, and none was considered to be vaccination related. 28 days after 3rd vaccination, the seroconversion rates in 1sIPV+2bOPV (DC), 1sIPV+2bOPV (liquid), 2sIPV+1bOPV (DC), 2sIPV+1bOPV (liquid) group, were 99%, 100%, 99% and 99% (χ2=0.94, P=0.815) , respectively, for type Ⅰ poliovirus; and 47%, 57%, 80%, 79% (χ2=31.56, P<0.001) , respectively, for type Ⅱ; and were 100%, 99%, 100%, 99% (χ2=2.02, P=0.568) , respectively, for type Ⅲ. In each group, the GMT of antibody against poliovirus typeⅠ were 4 539.68, 6 243.43, 6 819.53 and 7 916.29 (F=25.87, P<0.001) , respectively; Type Ⅱ were 12.98, 10.54, 63.75 and 84.21 (F=8.68, P=0.034) , respectively; Type Ⅲ were 1 172.55, 1 416.03, 2 648.89 and 3 250.75 (F=14.50, P=0.002) , respectively.@*Conclusion@#On the same sequential schedules, there was no significant difference between the dosage forms, all of them showed good safety and immunogenicity. In the same dosage forms with different sequential schedules, the seroconversion rate was higher in 2 dose sIPV group than the 1 dose sIPV group, especially at the neutralizing antibody GMT level against polio type Ⅱ and Ⅲ after vaccination.
RESUMO
One unusual human G3P[3] group A rotavirus (RVA) strain M2-102 was identified in stool sample collected from a child with diarrhea in Guangxi Province, China in 2014. It is well known that G3P[3] is a genotype commonly identified in feline and canine RVAs. However, the preliminary phylogenetic analyses of the VP7 and VP4 genes of strain M2-102 indicated that these two genes were closely related to bat RVA strain MYAS33 and simian strain RRV, respectively, whereas both clustered distantly to feline/canine-like RVA strains. In this study, full genome sequencing and molecular analyses were conducted to obtain the true origin of strain M2-102. It was revealed that strain RVA/Human-wt/CHN/M2-102/2014/G3P[3] exhibited a G3-P[3]-I3-R3-C3-M3-A9-N3-T3-E3-H6 genotype constellation for VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5 genes. Phylogenetic analyses revealed that 5 genes (VP7, VP1, VP2, NSP2 and NSP3) from strain M2-102 were closely related to those of bat strain MYAS33 from Yunnan Province which was thought a true bat RVA strain rather than a virus transmitted between species, while another 5 genes (VP4, VP3, NSP1, NSP4 and NSP5) clustered closely with those of simian strain RRV, yet the VP6 gene was closely related to that of human G3P[9] strain AU-1 and AU-1-like RVAs. The epidemiological data indicated that the child infected with M2-102 came from a countryside village, located in Dong Autonomous County of Sanjiang (subtropical hilly wooded area), Liuzhou city in Guangxi Province which might provide natural environment for reassortment events occurring among animal and human RVAs. Therefore, the data suggest that human strain M2-102 might originate from multiple reassortment events among bat, simian and human AU-1-like RVAs, yet it is not clear whether the genomic backbone based on bat MYAS33 (5 genes) and simian RRV (5 genes) like rotaviruses had been obtained through reassortment before being transmitted to the human. This is the first report on whole genome analysis of human G3P[3] RVA from China.