Analysis of the characteristics of viral infections in children with diarrhea in Beijing from 2018 to 2022 / 中华预防医学杂志

Objective: To explore the characteristics of viral infections in children with diarrhea in Beijing from 2018 to 2022. Methods: Real-time PCR and enzyme-linked immunosorbent assay were used to detect viral nucleic acid of Norovirus (NoV), Sappovirus (SaV), Astrovirus (AstV), Enteric Adenovirus (AdV) or antigen of Rotavirus (RV) in 748 stool samples collected from Beijing Capital Institute of Pediatrics from January 2018 to December 2021. Subsequently, the reverse transcription PCR or PCR method was used to amplify the target gene of the positive samples after the initial screening, followed by sequencing, genotyping and evolution analysis, so as to obtain the characteristics of these viruses. Phylogenetic analysis was performed using Mega 6.0. Results: From 2018 to 2021, the overall detection rate of the above five common viruses was 37.6%(281/748)in children under 5 years old in Beijing. NoV, Enteric AdV and RV were still the top three diarrhea-related viruses, followed by AstV and SaV, accounting for 41.6%, 29.2%, 27.8%, 8.9% and 7.5%, respectively. The detection rate of co-infections with two or three diarrhea-related viruses was 4.7% (35/748). From the perspective of annual distribution, the detection rate of Enteric AdV was the highest in 2021, while NoV was predominant in the other 4 years. From the perspective of genetic characteristics, NoV was predominant by GⅡ.4, and after the first detection of GⅡ.4[P16] in 2020, it occupied the first two gene groups together with GⅡ.4[P31]. Although the predominant RV was G9P[8], the rare epidemic strain G8P[8] was first detected in 2021. The predominant genotypes of Enteric AdV and AstV were Ad41 and HAstV-1. SaV was sporadic spread with a low detection rate. Conclusion: Among the diarrhea-related viruses infected children under 5 years of age in Beijing, the predominant strains of NoV and RV have changed and new sub-genotypes have been detected for the first time, while the predominant strains of AstV and Enteric AdV are relatively stable.

Observation on two kinds of recombinant hepatitis B vaccines used in populations with different immunity / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the immunity status on different hepatitis B vaccines currently being used in Beijing.</p><p><b>METHODS</b>College students who had not received hepatitis B vaccine and children who had received whole-course immunization at birth, were tested HBsAg, anti-HBs and anti-HBc. All the test-negative cases were served as research subjects. 3 doses recombinant hepatitis B vaccines were given to the college students, following the 0, 1, 6 months schedule. Among which, 140 cases received recombinant beer yeast hepatitis B vaccine (BY vaccine, 10 microg, 5 microg, 5 microg), and 140 cases with recombinant hansenula polymorpha hepatitis B vaccine (HP vaccine, 10 microg, 10 microg, 10 microg). 1 dose was given for boosting immunization to 98 children, in which 49 cases with BY vaccine (5 microg) and 49 cases with HP vaccine (10 microg). Anti-HBs was tested 1 month after.</p><p><b>RESULTS</b>The total positive (> or = 10 mIU/ ml) rate was lower among BY vaccine group than HP vaccine group for the college students (93.5 %, 99.3% , P<0.05), but no statistical difference on GMT(81.2 mIU/ml, 94.6 mIU/ml, P>0.05) was found. For males, the positive rate and GMT were lower in BY vaccine group than in HP vaccine group (85.7% ,100.0%, P<0.01)(56.6 mIU/ml, 98.6 mIU/ml, P<0.01), but with no statistical difference for females (98.8%, 98.5%, P> 0.05) (103.4 mIU/ml, 90.3 mlU/ml, P> 0.05). For the same vaccine, the positive rate and GMT were lower in males than in females when using BY vaccine (85.7% , 98.8%, P<0.01)(56.6 mIU/ml,103.4 mIU/ml, P< 0.01), but no statistical difference was found on HP vaccine(100.0%, 98.5%, P>0.05)(98.6 mIU/ml, 90.3 mIU/ml, P>0.05). The positive rate of anti-HBs was decreasing along with age among the children who had received a whole-course immunization at birth (P <0.01). 98.6 % of the 70 negative cases appeared positive conversion after receiving 1 dose and the GMT raised significantly by 15 times. No statistical difference was found between the two kinds of vaccines(100.0%, 97.4%, P>0.05)(80.5 mIU/ml, 68.5 mIU/ml, P>0.05).</p><p><b>CONCLUSIONS</b>The type of vaccine and sex were related to the effects, better with HP vaccine than BY vaccine in males but was the same for females in adults receiving basic immunization according to the conventional doses. Both kinds of vaccines were ideal when children receiving boosting immunization. The immune memory was good for persons who had received primary immunization with recombinant vaccine but antibody appeared negative conversion. It was not necessary to boost immunization within 6 years after a whole-course immunization with recombinant hepatitis B vaccine in infancy.</p>