Report of the 5th European expert meeting on rotavirus vaccination (EEROVAC)

The Fifth European Expert Meeting on Rotavirus Vaccination was convened in Utrecht, The Netherlands, in March 2017. The 2-day meeting included invited lectures as well as original oral and poster presentations and brought together experts from 21 countries. Summary findings of the meeting include: Rotavirus vaccination programmes in Europe have resulted in reductions of 60–90% in rotavirus outpatient visits and hospitalizations. Long term trends indicate this impact is sustained over the years. Herd effects, protecting unvaccinated children and neonates too young to be vaccinated have been observed in many European countries. Early evidence now also suggests that rotavirus vaccination may be instrumental in the prevention of celiac disease. Special attention should be given to preterm infants, who may age out of the vaccination window before hospital discharge and to HIV infected children who are at increased risk of severe rotavirus AGE. There is a small but increased risk of IS following rotavirus vaccination and parents should therefore be informed about possible signs and symptoms of IS. New insights in rotavirus genetic susceptibility and interactions with microbiome may open opportunities for interventions to improve protection by vaccination, in particular in LMIC. The development of several novel rotavirus vaccines discussed at the meeting is also promising in this respect.

Immunogenicity and safety of concomitant administration of meningococcal serogroup B (4CMenB) and serogroup C (MenC-CRM) vaccines in infants: A phase 3b, randomized controlled trial

BACKGROUND

After implementation of routine infant MenC vaccination, MenB remains a serious cause of meningococcal disease, yet to be targeted by vaccination programs in several countries. This study (NCT01339923) investigated the immunogenicity and safety of MenC CRM-conjugated vaccine (MenC-CRM) concomitantly administered with MenB vaccine (4CMenB).

METHODS

Infants (N=251) were randomised 1:1 to receive 4CMenB and MenC-CRM (Group 1) or MenC-CRM alone (Group 2) at 3 and 5months (M3, M5) and a booster at 12months of age (M12), and pneumococcal vaccine at M3, M5, M7, M12. Antibody responses to meningococcal vaccines were measured at M3, M6, M12, and M13. Non-inferiority of MenC-CRM response in Group 1 vs Group 2 was demonstrated at M6 and M13, if the lower limit of the 95% confidence interval (LL95%CI) of the difference in percentage of infants with hSBA titres ≥1:8 was >-10%. Sufficiency of MenB response was achieved if LL95%CI of the percentage of infants with hSBA titres ≥1:4 against fHbp, NadA and PorA strains was ≥70% at M6 or ≥75% at M13. Adverse events (AEs) were collected for 7days post-vaccination, and serious AEs (SAEs) and medically attended AEs throughout the study.

RESULTS

Non-inferiority of MenC response in Group 1 vs Group 2 (LL95%CI -6.4% [M6]; -5.2% [M13]) and sufficiency of MenB response in Group 1 (LL95%CI 92%, 90%, 89% [M6]; 97%, 92%, 93% [M13] against fHbp, NadA, PorA, respectively) were demonstrated. Higher rates of mild to moderate solicited AEs were reported in Group 1. Unsolicited AEs and SAEs incidences were similar across groups.

CONCLUSIONS

Concomitant administration of MenC-CRM and 4CMenB in infants was immunogenic, resulting in non-inferior responses against MenC compared to MenC-CRM alone and demonstration of sufficient immune response to MenB, after primary and booster vaccination. Reactogenicity was higher for concomitant vaccines administration, but no safety concerns were identified.

Expected and Unexpected Effects of Vaccination

Vaccination is widely considered to be one of the greatest medical achievements of civilization and one of the top major breakthroughs of humanity.

Diagnostic Test Accuracy of a 2-Transcript Host RNA Signature for Discriminating Bacterial vs Viral Infection in Febrile Children

IMPORTANCE

Because clinical features do not reliably distinguish bacterial from viral infection, many children worldwide receive unnecessary antibiotic treatment, while bacterial infection is missed in others.

OBJECTIVE

To identify a blood RNA expression signature that distinguishes bacterial from viral infection in febrile children.

DESIGN, SETTING, AND PARTICIPANTS

Febrile children presenting to participating hospitals in the United Kingdom, Spain, the Netherlands, and the United States between 2009-2013 were prospectively recruited, comprising a discovery group and validation group. Each group was classified after microbiological investigation as having definite bacterial infection, definite viral infection, or indeterminate infection. RNA expression signatures distinguishing definite bacterial from viral infection were identified in the discovery group and diagnostic performance assessed in the validation group. Additional validation was undertaken in separate studies of children with meningococcal disease (n = 24) and inflammatory diseases (n = 48) and on published gene expression datasets.

EXPOSURES

A 2-transcript RNA expression signature distinguishing bacterial infection from viral infection was evaluated against clinical and microbiological diagnosis.

MAIN OUTCOMES AND MEASURES

Definite bacterial and viral infection was confirmed by culture or molecular detection of the pathogens. Performance of the RNA signature was evaluated in the definite bacterial and viral group and in the indeterminate infection group.

RESULTS

The discovery group of 240 children (median age, 19 months; 62% male) included 52 with definite bacterial infection, of whom 36 (69%) required intensive care, and 92 with definite viral infection, of whom 32 (35%) required intensive care. Ninety-six children had indeterminate infection. Analysis of RNA expression data identified a 38-transcript signature distinguishing bacterial from viral infection. A smaller (2-transcript) signature (FAM89A and IFI44L) was identified by removing highly correlated transcripts. When this 2-transcript signature was implemented as a disease risk score in the validation group (130 children, with 23 definite bacterial, 28 definite viral, and 79 indeterminate infections; median age, 17 months; 57% male), all 23 patients with microbiologically confirmed definite bacterial infection were classified as bacterial (sensitivity, 100% [95% CI, 100%-100%]) and 27 of 28 patients with definite viral infection were classified as viral (specificity, 96.4% [95% CI, 89.3%-100%]). When applied to additional validation datasets from patients with meningococcal and inflammatory diseases, bacterial infection was identified with a sensitivity of 91.7% (95% CI, 79.2%-100%) and 90.0% (95% CI, 70.0%-100%), respectively, and with specificity of 96.0% (95% CI, 88.0%-100%) and 95.8% (95% CI, 89.6%-100%). Of the children in the indeterminate groups, 46.3% (63/136) were classified as having bacterial infection, although 94.9% (129/136) received antibiotic treatment.

CONCLUSIONS AND RELEVANCE

This study provides preliminary data regarding test accuracy of a 2-transcript host RNA signature discriminating bacterial from viral infection in febrile children. Further studies are needed in diverse groups of patients to assess accuracy and clinical utility of this test in different clinical settings.

Transcriptomic profiling in childhood H1N1/09 influenza reveals reduced expression of protein synthesis genes

We compared the blood RNA transcriptome of children hospitalized with influenza A H1N1/09, respiratory syncytial virus (RSV) or bacterial infection, and healthy controls. Compared to controls, H1N1/09 patients showed increased expression of inflammatory pathway genes and reduced expression of adaptive immune pathway genes. This was validated on an independent cohort. The most significant function distinguishing H1N1/09 patients from controls was protein synthesis, with reduced gene expression. Reduced expression of protein synthesis genes also characterized the H1N1/09 expression profile compared to children with RSV and bacterial infection, suggesting that this is a key component of the pathophysiological response in children hospitalized with H1N1/09 infection.

Immunogenicity of a combination vaccine containing diphtheria toxoid, tetanus toxoid, three-component acellular pertussis, hepatitis B, inactivated polio virus, and Haemophilus influenzae type b when given concomitantly with 13-valent pneumococcal conjugate vaccine

Two randomized trials of 13-valent pneumococcal conjugate vaccine (PCV13) relative to PCV7 evaluated the immune responses of coadministered antigens comprising Infanrix(®) hexa/Infanrix(®)-IPV+Hib (diphtheria, tetanus, 3-component acellular pertussis, hepatitis B, inactivated poliovirus, and Haemophilus influenzae type b). After the 3-dose infant series, immunogenic noninferiority was demonstrated for all concomitantly administered antigens between the PCV13 and PCV7 groups. All antigens elicited good booster responses after the toddler dose except pertussis toxoid; however, 99.6% subjects achieved pertussis toxoid protective antibody level ≥5EU/mL in both groups. These results support the concomitant administration of PCV13 and Infanrix hexa/Infanrix-IPV+Hib as part of routine immunization schedules.

Multicenter prospective study analysing the role of rotavirus on acute gastroenteritis in Spain

BACKGROUND

Paediatric rotavirus gastroenteritis is the most frequent cause of acute gastroenteritis (AGE) in children up to 5 years of age worldwide.

AIM

To analyse the clinical characteristics of AGE caused by rotavirus comparing to AGE caused by other agents.

METHODS

The study was conducted in 30 health-care centers in Spain (25 hospitals and five primary centers) between January and March 2006. Children with AGE up to 2 years of age were included. Stool samples were analysed using immunochromatographic test to identify rotavirus infection. Clinical and epidemiological data were analysed.

RESULTS

A total of 1192 children were enrolled (mean age: 11.2 months). Fever, Vomiting, weakness and dehydration were more frequent in rotavirus-positive AGE cases. Severity score was higher and hospitalization was likely in AGE caused by rotavirus. Family AGE illness was more frequent in children with rotavirus-positive AGE. Breastfeeding was found as a protective factor against Rotavirus AGE.

CONCLUSION

Rotavirus is the primary causal agent of AGE in children under 2 years of age in Spain, causing more severe symptoms and more hospital admissions than other causal agents. Our data support the interest of the introduction of the available rotavirus vaccines in the Spanish immunization schedule.