Safety of routine childhood vaccine coadministration versus separate vaccination

Available evidence on the co-administration of the four-component meningococcal B vaccine (4CMenB) with three vaccines at the same visit among pediatric individuals

Vaccine co-administration is a useful strategy for improving vaccine coverage and adherence. In Italy, an update to the national immunization program (NIP) in 2023 included recommendations for co-administration of pediatric vaccines, including the four-component vaccine for meningococcus B (4CMenB), pneumococcal conjugate vaccine (PCV), hexavalent vaccines, and oral rotavirus vaccines. Safety is a major concern when considering vaccine co-administration; therefore, a literature review of the available evidence on 4CMenB co-administration with PCV, hexavalent/pentavalent, and rotavirus vaccines was performed. Of 763 publications screened, two studies were reviewed that reported safety data on 4CMenB co-administration with PCV, hexavalent/pentavalent, and rotavirus vaccines in infants aged 0-24 months. Overall, these studies supported that there were no significant safety signals when co-administering 4CMenB with PCV, hexavalent/pentavalent, and rotavirus vaccines, compared with individual vaccination. This review provides key insights for healthcare professionals on the tolerability of co-administering 4CMenB with routine vaccines.

Surveillance for adverse events following immunization with DTaP-containing combination vaccines in Linping, China, 2019-2022

Background

The DTaP-Hib and DTaP-IPV/Hib combination vaccine can be used as a substitute for the diphtheria, tetanus, and acellular pertussis combined vaccine (DTaP). We aimed to evaluate the safety of multi-component vaccines containing DTaP by analyzing the reporting rates and characteristics of adverse events following immunization (AEFIs) in Linping District during the years 2019 to 2022.

Methods

We obtained data of AEFI and vaccination from the National AEFI Surveillance System of China and Zhejiang Municipal Immunization Information Management System, respectively, during 2019-2022 for a descriptive, epidemiological analysis.

Results

The total number of AEFI reported following vaccinations with DTaP-containing combination vaccines was 802 in Linping District from 2019 to 2022. The overall reporting rates of AEFIs following DTaP, DTaP-Hib, and DTaP-IPV/Hib vaccinations were 445.72 (537 cases), 536.29 (45 cases), and 306.13 (220 cases) per 100,000 doses in Linping District from 2019 to 2022, respectively. Only one case of a serious AEFI following DTaP vaccination, with a reporting rate of 0.83 per 100,000 doses. The composition ratio of vaccine product-related reactions for DTaP, DTaP-Hib, and DTaP-IPV/Hib were 99.81, 97.78, and 100.00%, respectively. The composition ratio of coincidental events for DTaP and DTaP-Hib were 0.19 and 2.22%, respectively. The reporting rates of total AEFIs for DTaP-IPV/Hib were lower than for DTaP. The reporting rate of local induration for DTaP-Hib was lower than for DTaP, and the reporting rates of local redness & swelling and local induration for DTaP-IPV/Hib were both lower than for DTaP. DTaP-IPV/Hib had a higher proportion of AEFIs in first quarter compared to DTaP. The reporting rate after the second dose of DTaP-Hib was higher than that of DTaP, and the reporting rates of AEFIs after the first dose and third dose of DTaP-IPV/Hib were lower than DTaP.

Conclusion

The reported AEFIs to multi-component vaccines containing DTaP components during 2019-2022 in Linping District were mainly mild vaccine reactions. DTaP-containing combination vaccines demonstrated a good safety profile.

Intussusception and Other Adverse Event Surveillance after Pilot Introduction of Rotavirus Vaccine in Nam Dinh and Thua Thien Hue Provinces-Vietnam, 2017-2021

Rotavin-M1 (POLYVAC) was licensed in Vietnam in 2012. The association of Rotavin-M1 with intussusception, a rare adverse event associated with rotavirus vaccines, and with adverse events following immunization (AEFI) have not been evaluated and monitored under conditions of routine use. From February 2017 to May 2021, we conducted a pilot introduction of Rotavin-M1 into the routine vaccination program in two provinces. Surveillance for intussusception was conducted at six sentinel hospitals. AEFI reports at 30 min and 7 days after vaccination were recorded. Among 443 children <12 months of age admitted for intussusception, most (92.3%) were children ≥ 6 months. Of the 388 children who were age-eligible to receive Rotavin-M1, 116 (29.9%) had received ≥1 dose. No intussusception cases occurred in the 1-21 days after dose 1 and one case occurred on day 21 after dose 2. Among the 45,367 children who received ≥1 dose of Rotavin-M1, 9.5% of children reported at least one AEFI after dose 1 and 7.3% after dose 2. Significantly higher AEFI rates occurred among children given Rotavin-M1 with pentavalent vaccines (Quinvaxem®, ComBE Five®) compared to Rotavin-M1 without pentavalent vaccines. There was no association between intussusception and Rotavin-M1. The vaccine was generally safe when administered alone and when co-administered with other vaccines.

Insights and expectations of healthcare professionals on the implementation of the updated pediatric regional immunization Calendar in Calabria, Italy

The Regional Immunization Calendar in Calabria, a region of Italy, was updated in 2022, introducing optional co-administration of three injectable vaccines, with one oral vaccine, at 3 and 5 months old, and three injectable vaccines at 13-14 months old. In this project, the opinions and expectations of healthcare professionals (HCPs) in Calabria were investigated, with respect to the updated recommended practices. An 11-question survey was developed, which addressed concepts and topics related to immunization calendar implementation. Focus group discussions were also organized to provide further insight on the survey findings. A total of 132 HCPs completed the survey (86 public health providers [PHs] and 46 family pediatricians [FPs]). Overall, ≥50% of respondents agreed that vaccine co-administration would be advantageous for public health by reducing the number of vaccination sessions required. Most PHs and FPs agreed that dissemination of available safety data on vaccine co-administration is a necessary action to facilitate effective implementation of the strategy into clinical practice. The importance of safety data related to vaccine co-administration was supported further by discussions held in PH and FP focus groups. Overall, these findings demonstrate support from HCPs in Calabria for vaccine co-administration, and highlight key activities needed for successful uptake.

Safety of concomitant administration of inactivated hepatitis A vaccine with other vaccines in children under 16 years old in post-marketing surveillance

BACKGROUND

Concomitant administration refers to the receipt of two or more vaccines during a single healthcare encounter, which is an efficient way to increase vaccination coverage in children. However, the post-marketing safety studies of concomitant administration are scarce. Inactivated hepatitis A vaccine (Healive®) has been used widely in China and other countries for more than a decade. We aimed to explore the safety of Healive® co-administered with other vaccines compared to Healive® alone in children under 16 years old.

METHODS

We retrieved Adverse Events Following Immunization (AEFI) cases and vaccination doses of Healive® during 2020-2021 in Shanghai, China. The AEFI cases were divided into concomitant administration group and Healive® alone group. We used administrative data on vaccine doses as denominators to calculate and compare crude reporting rates between groups. We also compared baseline gender and age distribution, clinical diagnoses, and time interval from vaccination to onset of symptoms between groups.

RESULTS

A total 319,247 doses of inactivated hepatitis A vaccine (Healive®) were used and 1,020 AEFI cases (319.50 per million doses) associated with Healive® were reported during 2020-2021 in Shanghai. There were 259,346 doses concomitantly administered with other vaccines and 830 AEFI cases (320.04 per million doses) were reported. There were 59,901 doses of Healive® that vaccinated alone, with 190 AEFI cases (317.19 per million doses). There was only one case with serious AEFI in concomitant administration group, with a rate of 0.39 per million doses. Reported rates of AEFI cases were similar between groups in general (p > 0.05).

CONCLUSION

Concomitant administration of inactivated hepatitis A vaccine (Healive®) with other vaccines has a similar safe profile as Healive® alone.