Bactericidal killing of meningococcal W strains isolated in Argentina by the sera of adolescents and infants immunized with 4-component meningococcal serogroup B vaccine (4CMenB)

Invasive meningococcal disease (IMD) is a life-threatening disease caused by meningococcal serogroups A, B, C, W, X, and Y, of which B and W are most common in Argentina. The 4-component meningococcal serogroup B (4CMenB) vaccine contains three purified recombinant protein antigens (Neisseria adhesin A [NadA], factor H binding protein [fHbp], and Neisserial Heparin Binding Antigen [NHBA]) and outer membrane vesicles (OMV), which is derived from the New Zealand epidemic strain and contains Porin A 1.4. These antigens are present and conserved in strains that belong to other serogroups. In this study, we show that 10/11 (91%) meningococcal serogroup W (MenW) strains selected to be representative of MenW isolates that caused IMD in Argentina during 2010-2011 were killed in bactericidal assays by the sera of adolescents and infants who had been immunized with the 4CMenB vaccine. We also show that MenW strains that caused IMD in Argentina during 2018-2021 were genetically similar to the earlier strains, indicating that the 4CMenB vaccine would likely still provide protection against current MenW strains. These data highlight the potential of 4CMenB vaccination to protect adolescents and infants against MenW strains that are endemic in Argentina.

Parental awareness of Meningococcal B vaccines and willingness to vaccinate their teens

Background:

In the US, Meningococcal B (MenB) vaccines were first licensed in 2014. In 2015, the Advisory Committee on Immunization Practices recommended that parents of teens talk to their provider about receiving MenB vaccine, rather than issuing a routine recommendation. We assessed parental awareness of MenB vaccines and willingness to vaccinate their teens with MenB vaccines compared to MenACWY vaccines, which have been routinely recommended for many years.

Methods:

We surveyed parents of teens attending high school in 2017–18 during the Minnesota State Fair. Parents reported via iPad their knowledge of and concern about meningococcal disease and their awareness of and willingness to vaccinate with MenB and MenACWY vaccines. We assessed the relationship between meningococcal disease knowledge and concern, MenB and MenACWY vaccine awareness, and willingness to vaccinate with MenB and MenACWY using adjusted logistic regression.

Results:

Among 445 parents, the majority had not heard of the newly introduced MenB vaccines Bexsero^® (80.0%; 95% CI: 76.0–83.6) or Trumenba^® (82.0%; 95% CI: 78.1–85.5) or the MenACWY vaccines Menactra^® or Menveo^® (68.8%; 95% CI: 64.2–73.0). The majority were at least somewhat willing to vaccinate their teen with MenB vaccine (89.6%; 95% CI: 86.5, 92.3) and MenACWY vaccine (91.2%; 95% CI: 88.2, 93.7). Awareness of MenB vaccines (OR: 3.8; 95% CI: 1.2–12.2) and concern about meningococcal disease (OR: 3.1; 95% CI: 1.5–6.3) were significantly associated with willingness to vaccinate with MenB vaccine.

Conclusions:

Awareness of MenB vaccine is lacking among parents of teens but is an important predictor of willingness to vaccinate with the newly licensed MenB vaccines.

Cost-utility analysis of a nationwide vaccination programme against serogroup B meningococcal disease in Israel

OBJECTIVES

Using cost-utility analysis, to evaluate whether or not to adopt a Neisseria meningitidis serogroup B vaccination programme for Israeli children.

METHODS

Epidemiological, demographic, health service utilisation and economic data were integrated into a spreadsheet model to calculate the cost per averted disability-adjusted life year (DALY) of the intervention.

RESULTS

Assuming 78 % vaccine efficacy with no herd immunity, vaccination will prevent 223 cases and 22 deaths over a 100-year period. Based on vaccine price of $60 per dose, total intervention costs ($315,400,000) are partially offset by a $22,700,000 reduction in treatment and sequelae costs as a result of decreased morbidity. The intervention was not cost-effective since the net cost ($292,700,000) per averted DALY gained (1249 mostly due to decreased mortality) was $234,394. Additional two dose catch-up programmes vaccinating children in cohorts aged 1-2 to 1-13 were also not cost-effective.

CONCLUSIONS

The vaccination will become cost-effective if vaccine costs fall below $19.44 per dose. However, in identified high risk areas, the vaccine would be cost-effective and could be recommended for use both with and without catch-up campaigns.