Building an immunity fence against measles

Measles antibody seropositivity among children with allergic diseases: A cross-sectional study in the Japan Environment & Children's Pilot Study

BACKGROUND

The relationship between allergic individuals and their responsiveness to routine vaccines has rarely been investigated. This study examined whether the seroprevalence of measles antibody differed between children with and without allergic diseases in the general pediatric population.

METHODS

The cross-sectional study was performed within a prospective general birth cohort (a pilot study of the Japan Environment & Children's Pilot Study [JECS]) of children aged 8 years. The clinical history of allergic diseases, measles, and the concentration of measles immunoglobulin G titers in serum enzyme immunoassay were examined. Fisher's exact tests were used to assess the relationships between the allergic characteristics of the children and their measles antibody positivity rates.

RESULTS

This study included 162 children. Any allergic disease was reported in 75 (46.3%). The measles antibody positivity rate was 94.7% among children with any allergic diseases and 92.0% among children without allergic diseases. Our results revealed no differences in measles antibody seropositivity between children with allergies and controls.

CONCLUSIONS

Children with allergies mount and maintain a comparable immune response to the measles vaccine.

Vaccination Policies: Between Best and Basic Interests of the Child, between Precaution and Proportionality

How should liberal-democratic governments deal with emerging vaccination hesitancy when that leads to the resurgence of diseases that for decades were under control? This article argues that vaccination policies should be justified in terms of a proper weighing of the rights of children to be protected against vaccine-preventable diseases and the rights of parents to raise their children in ways that they see fit. The argument starts from the concept of the ‘best interests of the child involved’. The concept is elaborated for this context into the dual regime structure in which parents have fiduciary authority over what they consider to be best for their child, and the state has fiduciary authority over a child’s basic interests. This argument leads to conditional mandatory vaccination programs that should be informed by a correct balancing of the two legal principles of proportionality and precaution. This results in contextual childhood vaccination policies of upscaling interference: a three-tiered approach of increased intrusion, from voluntary program when possible and mandatory or even compulsory programs when necessary to protect the child’s basic interests.

On religious and secular exemptions: A case study of childhood vaccination waivers

This paper analyses exemptions to general law through the prism of vaccine waivers in the United States. All US states legally require the vaccination of children prior to school or daycare entry; however, this obligation is accompanied with a system of medical, religious, and/or philosophical exemptions. Nonmedical exemptions became subject of discussion after the 2015 Disneyland measles outbreak in California, which unequivocally brought to light what had been brewing below the surface for a while: a slow but steady decline in vaccination rates in Western societies, resulting in the reoccurrence of measles outbreaks. This can be traced back to an increasing public questioning of vaccines by a growing anti-vaccination movement. In reaction to the outbreak and the public outrage it generated, several states proposed-and some already passed-bills to eliminate nonmedical exemptions. I analyze two questions. First, can legal exemptions from mandatory childhood vaccination schemes for parents who are opposed to vaccination (still) be justified? Second, should legal exemptions be limited to religious objections to vaccination, or should they also be granted to secular objections? Although the argument in the paper starts from the example of the US, it seeks to provide a more general philosophical reflection on the question of exemptions from mandatory childhood vaccination.

Serological assessment of measles-rubella vaccination catch-up campaign among university students

BACKGROUND

In Japan, 5000-300,000 persons contracted measles every year until 2001. The measles/rubella-combined (MR) vaccination at age 17-18 years (phase 4 MR vaccination: MR-IV) was launched in 2008 in Japan as a measles-rubella catch-up campaign. A serological assessment of this campaign has not been thoroughly performed.

METHODS

Titers of anti-measles and anti-rubella immunoglobulin G antibodies, and past medical history including measles and rubella vaccination and infection were obtained from first-year university students in 2008 and 2009, and the immune status against measles and rubella was compared between students at the target MR-IV age (the target age group) and those 1 year older than the target age (non-target age group).

RESULTS

A total of 186 students were in the target age group and 146 were in the non-target age group. The proportion of students with a history of measles and rubella infection was not significantly different between the two groups (8.8% vs. 6.3%, P = 0.41 and 11.0% vs. 9.9%, P = 0.75, respectively). A history of two or more measles and rubella vaccinations was significantly more frequent in the target age group (85.2% and 54.9%, respectively) than in the non-target age group (20.8% and 13.2%, respectively; both P < 0.001). Prevalence of seropositivity for measles and for rubella was also higher in the target age group (98.9% and 97.8%, respectively) than in the non-target age group (91.0% and 87.5%, respectively; both P < 0.001).

CONCLUSIONS

The MR-IV catch-up campaign helped achieve herd immunity and will contribute to the elimination of measles and rubella.

Genetic polymorphisms in host antiviral genes: associations with humoral and cellular immunity to measles vaccine

Host antiviral genes are important regulators of antiviral immunity and plausible genetic determinants of immune response heterogeneity after vaccination. We genotyped and analyzed 307 common candidate tagSNPs from 12 antiviral genes in a cohort of 745 schoolchildren immunized with two doses of measles-mumps-rubella (MMR) vaccine. Associations between SNPs/haplotypes and measles virus-specific immune outcomes were assessed using linear regression methodologies in Caucasians and African-Americans. Genetic variants within the DDX58/RIG-I gene, including a coding polymorphism (rs3205166/Val800Val), were associated as single-SNPs (p≤0.017; although these SNPs did not remain significant after correction for false discovery rate/FDR) and in haplotype-level analysis, with measles-specific antibody variations in Caucasians (haplotype allele p-value=0.021; haplotype global p-value=0.076). Four DDX58 polymorphisms, in high LD, demonstrated also associations (after correction for FDR) with variations in both measles-specific IFN-γ and IL-2 secretion in Caucasians (p≤0.001, q=0.193). Two intronic OAS1 polymorphisms, including the functional OAS1 SNP rs10774671 (p=0.003), demonstrated evidence of association with a significant allele-dose-related increase in neutralizing antibody levels in African-Americans. Genotype and haplotype-level associations demonstrated the role of ADAR genetic variants, including a non-synonymous SNP (rs2229857/Arg384Lys; p=0.01), in regulating measles virus-specific IFN-γ Elispot responses in Caucasians (haplotype global p-value=0.017). After correction for FDR, 15 single-SNP associations (11 SNPs in Caucasians and 4 SNPs in African-Americans) still remained significant at the q-value<0.20. In conclusion, our findings strongly point to genetic variants/genes, involved in antiviral sensing and antiviral control, as critical determinants, differentially modulating the adaptive immune responses to live attenuated measles vaccine in Caucasians and African-Americans.

Measles in a highly vaccinated society: the 2007-08 outbreak in Israel

BACKGROUND

Despite success in controlling measles through a national immunization program, Israel recently experienced its largest measles outbreak since 1994.

METHODS

Using data reported by health district offices to the Ministry of Health, an epidemiological analysis of the 2007-08 measles outbreak was performed.

RESULTS

1467 measles cases were reported in Israel, primarily among ultra-orthodox Jewish communities in the Jerusalem Health District and to a lesser extent in other areas. The highest age-specific incidence rate (122.5 per 100,000) occurred among infants. 38.6% of all measles patients were under the age of five, and 53.4% were under the age of ten. 186 patients (12.7%) were hospitalized; there were no fatalities. Only 4.6% of measles patients had been fully vaccinated for their age.

CONCLUSION

To minimize the risk of future outbreaks in Israel, successful marketing of the MMR vaccine to under-vaccinated sub-groups is essential.

The strategy for prevention of measles and rubella prevalence with measles-rubella (MR) vaccine in Japan

To eliminate the indigenous measles and rubella virus by 2012 in Japan, the strategy fro prevention of measles and rubella prevalence with measles-rubella (MR) vaccine was proposed. Since the vast majority of 1-year old infants are susceptible to measles and rubella, the first MR vaccine, the first MR vaccine should be administered at 1-year old to sustain the herd immunity. Since significant elevation of measles and rubella antibody titers were eliminated in a half of children after the second dose, the second dose of of MR vaccine within 1 year before elementary school entry is the effective maneuver. Moreover, supplement MR vaccination to the teenage group and 20-29 years' group might be necessary, because the mean measles antibody titers in this group were significantly lower compared with those in the older individuals' groups.