Measles, Mumps, and Rubella Vaccines

Antigenic breadth: a missing ingredient in HSV-2 subunit vaccines?

The successful human papillomavirus and hepatitis B virus subunit vaccines contain single viral proteins that represent 22 and 12%, respectively, of the antigens encoded by these tiny viruses. The herpes simplex virus 2 (HSV-2) genome is >20 times larger. Thus, a single protein subunit represents 1% of HSV-2's total antigenic breadth. Antigenic breadth may explain why HSV-2 glycoprotein subunit vaccines have failed in clinical trials, and why live HSV-2 vaccines that express 99% of HSV-2's proteome may be more effective. I review the mounting evidence that live HSV-2 vaccines offer a greater opportunity to stop the spread of genital herpes, and I consider the unfounded 'safety concerns' that have kept live HSV-2 vaccines out of U.S. clinical trials for 25 years.

Chimeric derivatives of hepatitis B virus core particles carrying major epitopes of the rubella virus E1 glycoprotein

Three variants of the major rubella virus (RV) E1 protein virus-neutralizing epitope from position 214 to 285 were exposed on the hepatitis B virus (HBV) C-terminally truncated core (HBcΔ) in a virus-like particle (VLP) vector and were produced in Escherichia coli. All three chimeras demonstrated VLPs in bacterial cell lysates, but only HBcΔ-E1(245-285) demonstrated the correct VLP structure after purification. The other chimeras, HBcΔ-E1(214-285) and HBcΔ-E1(214-240), appeared after purification as non-VLP aggregates of 100 to 900 nm in diameter according to dynamic light scattering data. All three variants possessed the intrinsic antigenic activity of RV E1, since they were recognized by natural human anti-RV E1 antibodies and induced an anti-RV E1 response in mice. HBcΔ-E1(214-240) and HBcΔ-E1(245-285) can be regarded as prototypes for a putative RV vaccine because they were able to induce antibodies recognizing natural RV E1 protein in RV diagnostic kits.

Herpes simplex virus 2 ICP0 mutant viruses are avirulent and immunogenic: implications for a genital herpes vaccine

Herpes simplex virus 1 (HSV-1) ICP0⁻ mutants are interferon-sensitive, avirulent, and elicit protective immunity against HSV-1 (Virol J, 2006, 3:44). If an ICP0⁻ mutant of herpes simplex virus 2 (HSV-2) exhibited similar properties, such a virus might be used to vaccinate against genital herpes. The current study was initiated to explore this possibility. Several HSV-2 ICP0⁻ mutant viruses were constructed and evaluated in terms of three parameters: i. interferon-sensitivity; ii. virulence in mice; and iii. capacity to elicit protective immunity against HSV-2. One ICP0⁻ mutant virus in particular, HSV-2 0ΔNLS, achieved an optimal balance between avirulence and immunogenicity. HSV-2 0ΔNLS was interferon-sensitive in cultured cells. HSV-2 0ΔNLS replicated to low levels in the eyes of inoculated mice, but was rapidly repressed by an innate, Stat 1-dependent host immune response. HSV-2 0ΔNLS failed to spread from sites of inoculation, and hence produced only inapparent infections. Mice inoculated with HSV-2 0ΔNLS consistently mounted an HSV-specific IgG antibody response, and were consistently protected against lethal challenge with wild-type HSV-2. Based on their avirulence and immunogenicity, we propose that HSV-2 ICP0⁻ mutant viruses merit consideration for their potential to prevent the spread of HSV-2 and genital herpes.

A review of licensed viral vaccines, some of their safety concerns, and the advances in the development of investigational viral vaccines

Viral vaccines could be considered among the most important medical achievements of the 20th century. They have prevented much suffering and saved many lives. Although some curative antiviral drugs exist, we desperately depend on efforts by academic, governmental and industrial scientists in the advancement of viral vaccines in the prevention and control of infectious diseases. In the next decade, we hope to see advancement in the development of current and investigational viral vaccines against childhood and adult infections. In this article, we will review the licensed viral vaccines, some of their safety concerns, and the advances in the development of investigational viral vaccines.

Full recovered meningoencephalomyelitis caused by mumps virus

Meningitis is the most common central nervous system complication of mumps virus, whereas encephalitis, cranial nerve palsies, poliradiculoneuritis are less common and myelitis caused by mumps virus is very rare [Nussinovitch et al., Acta Pediatrica (1992) 81, 183]. Lesions in young age as a result of severe acute transverse myelitis [shown on a magnetic resonance imaging (MRI) procedure] often has a viral cause. The case of a young male afflicted by meningoencephalomyelitis because of mumps virus is discussed.

Vaccines and immunotherapies for the prevention of infectious diseases having cutaneous manifestations

Although the development of antimicrobial drugs has advanced rapidly in the past several years, such agents act against only certain groups of microbes and are associated with increasing rates of resistance. These limitations of treatment force physicians to continue to rely on prevention, which is more effective and cost-effective than therapy. From the use of the smallpox vaccine by Jenner in the 1700s to the current concerns about biologic warfare, the technology for vaccine development has seen numerous advances. The currently available vaccines for viral illnesses include Dryvax for smallpox; the combination measles, mumps, and rubella vaccine; inactivated vaccine for hepatitis A; plasma-derived vaccine for hepatitis B; and the live attenuated Oka strain vaccine for varicella zoster. Vaccines available against bacterial illnesses include those for anthrax, Haemophilus influenzae, and Neisseria meningitidis. Currently in development for both prophylactic and therapeutic purposes are vaccines for HIV, herpes simplex virus, and human papillomavirus. Other vaccines being investigated for prevention are those for cytomegalovirus, respiratory syncytial virus, parainfluenza virus, hepatitis C, and dengue fever, among many others. Fungal and protozoan diseases are also subjects of vaccine research. Among immunoglobulins approved for prophylactic and therapeutic use are those against cytomegalovirus, hepatitis A and B, measles, rabies, and tetanus. With this progress, it is hoped that effective vaccines soon will be developed for many more infectious diseases with cutaneous manifestations.

Frequency of measles virus-specific CD4+ and CD8+ T cells in subjects seronegative or highly seropositive for measles vaccine

The protective effect of measles immunization is due to humoral and cell-mediated immune responses. Little is known about cell-mediated immunity (CMI) to measles vaccine virus, the relative contribution of CD4(+) and CD8(+) T cells to variability in such immune responses, and the immunologic longevity of the CMI after measles vaccination in humans. Our study characterizes cellular immune response in subjects seronegative or highly seropositive for measles vaccine immunoglobulin G-specific antibody, aged 15 to 25 years, previously immunized with two doses of measles-mumps-rubella II vaccine. We evaluated the ability of subjects to respond to measles vaccine virus by measuring measles virus-specific T-cell proliferation. We examined the frequencies of measles virus-specific memory Th1 and Th2 cells by an ELISPOT assay. Our results demonstrated that proliferation of T cells in seronegative subjects was significantly lower than that for highly seropositive subjects (P = 0.003). Gamma interferon (IFN-gamma) secretion predominated over interleukin 4 (IL-4) secretion in response to measles virus in both groups. The median frequency of measles virus-reactive CD8(+) T cells secreting IFN-gamma was 0.09% in seronegative subjects and 0.43% in highly seropositive subjects (P = 0.04). The median frequency of CD4(+) T cells secreting IL-4 in response to measles virus was 0.03% in seronegative subjects and 0.09% in highly seropositive subjects (P = 0.005). These data confirm the presence of measles virus-specific cellular immune responses post-measles vaccine immunization in humans. The detection of measles virus-induced IFN-gamma and IL-4 production by ELISPOT can be used to identify measles virus-specific low-frequency memory T cells in subjects immunized with measles vaccine. These differences agree in directionality with the observed antibody response phenotype.

Correlations between measles, mumps, and rubella serum antibody levels in Olmsted County school children

We examined correlations between serum antibody levels to determine whether individuals with low levels of antibody to one component of the measles, mumps, and rubella (MMR) vaccine were also likely to have low antibody levels to the other MMR vaccine components. Our results indicate that children who had a low antibody level to one component of the MMR vaccine had a modest probability of having a low antibody level to either of the other MMR vaccine components. Overall, we found small, but statistically significant, correlations between antibody levels that were largely unaffected by race, sex, age at immunization, and time since immunization. While the correlations we observed were modest, approximately 25% of our population was seronegative for at least one component of the MMR vaccine. Therefore, our results support the current policy of continuing to administer the trivalent MMR vaccine even when only a single low antibody titer is observed.

An outbreak of mumps among young adults in Vancouver, British Columbia, associated with 'rave' parties

In early 1997 an unexpectedly high number of cases of mumps was reported in Vancouver, British Columbia.

METHODS

A case control study was conducted to address four objectives: 1) Describe the outbreak and the population at risk, 2) examine the impact of mumps on this population, 3) identify personal risk factors for infection, and 4) test the hypothesis that social gatherings, 'rave' parties in particular, were a risk factor in this outbreak.

RESULTS

Mumps infection was associated with: attending a rave party [OR = 17; 95% CI: 2.7-710], residing in Vancouver [OR = 3.7; 95% CI: 1.4-10], and contact with a person with mumps [OR = 13; 95% CI: 2-552], during the 'exposure' period. Vaccine effectiveness, ascertained by self-reported immunization status, was 80% [95% CI: 29%-96%].

CONCLUSIONS

Attendance at rave parties was associated with mumps infection during this outbreak. Many persons aged 17-40 may remain susceptible to mumps; in BC these persons are eligible for one dose of MMR and should be encouraged to be vaccinated.

Immunogenetic mechanisms of antibody response to measles vaccine: the role of the HLA genes

Measles is the most transmissible human disease known to date. In the prevaccine era, virtually every member of each birth cohort was infected with this virus, leading to substantial morbidity and mortality, with millions of deaths on a global scale. At the current time, measles causes an estimated 1 to 1.5 million deaths per year world-wide. Since the advent of live, attenuated measles vaccines measles has been controlled, but not eradicated. Central to the goal of measles eradication are data relating to the influence of immunogenetics on vaccine immunogenicity. In this paper, the results of studies are reviewed executed in my laboratory examining the role of the class I and II HLA genes on the antibody response to measles vaccine.

An outbreak of measles in a highly immunised population: immunisation status and vaccine efficacy

An outbreak of 18 cases of measles in a primary school in the Australian Capital Territory in August and September 1993 provided the opportunity to study measles immunisation status and measles vaccine efficacy. Parents of 384 (78 per cent) of 491 children answered a questionnaire on recent illness consistent with measles and measles immunisation. Parents transcribed details of measles immunisation from the personal health record of the child to the questionnaire. Thirty-three per cent of cases and 3.4 per cent of the other children had not been immunised. Overall, 95 per cent of children had been immunised. The efficacy for all measles vaccines was estimated to be 90 per cent (95 per cent confidence interval (CI) 75 to 96) and for measles-mumps vaccine 87 per cent (CI 70 to 95). All of the immunised cases had received measles-mumps vaccine. There was no increased risk of measles infection in those who had been immunised at under 15 months of age compared with those immunised at 15 months or older, or in those who could not provide a date of immunisation compared with those who could. None of the children who had received two doses of vaccine caught measles. The date of immunisation was provided by 65 per cent of the respondents who said their children had been immunised. Asking parents to provide this date instead of viewing the health record is a less expensive way of assessing immunisation status but this method needs to be evaluated. Measles outbreaks still occur in highly immunised populations when vaccine efficacy appears to be acceptable.

Seroepidemiology, morbidity and vaccination strategies against rubella infection. Eight years experience in Oltrepò Pavese

Selective rubella vaccination of schoolgirls in Italy started 14 years ago following the United Kingdom strategy that was adopted in 1970. The aims of this program were to eliminate the risk of rubella among women of childbearing age, encourage the acquisition of immunity by natural infection during early childhood and allow the vaccine-induced antibody production by the circulating virus. On the basis of this program, between 1982 to 1990, a prospective serosurvey for rubella antibody in the province of Pavia was performed. The results showed a decline in the overall seropositivity rate for rubella antibodies from 57.7% in 1982 to 41.9% in 1984 followed by a remarkable increase in 1985 (53.3%) and in 1987 (56.5%). This trend was confirmed by the number of cases reported to the local Public Health Service. The results of this study provide further evidence of the need to change the current selective immunization policy in order to obtain a significant reduction of risk of the infection in the population.

Measles outbreak in Fife: which MMR policy?

The introduction of measles, mumps and rubella vaccine (MMR) into the United Kingdom childhood immunisation schedule has resulted in a substantial reduction in the incidence of all three diseases. None the less, there have recently been outbreaks of measles in parts of the country which have a record of high MMR uptake among young children. In these outbreaks it is mainly older children who have been affected. This report documents such an outbreak in Fife, an area with a very high MMR uptake among two-year-old children (96%). The current policy of giving MMR vaccine only once to children at 15 months of age may not be sufficient to enable the United Kingdom to achieve the WHO target of measles elimination by the year 2000. Other possible strategies to achieve this objective are discussed.

Measles epidemic: impact on pediatric oncology patients

Measles, a preventable disease, is again epidemic in the United States and is a threat to the immunocompromised pediatric oncology patient. In response to this latest epidemic, the Immunization Practices Advisory Committee has revised its recommendations for controlling an outbreak and has changed childhood immunization to a two-dose schedule. Full understanding of measles management is needed to effectively protect the pediatric oncology patient during the current epidemic. This article reviews the epidemiology, clinical presentation and management of measles, including recommendations for vaccinations, exposures, isolation, and patient and family education.

Rubella susceptibility of an infertile population

The recent trend reported by the CDC reaffirms that rubella continues to be a health care issue and should be a concern particularly for those who care for women in the childbearing age group. Immunization of all susceptible women will not only offer them protection but reduce the pool of susceptible individuals that can transmit the disease.