Seroepidemiological study of the transmission of the mumps virus in St. Lucia, West Indies

Seroprevalence of mumps before the introduction of mumps-containing vaccine in Lao PDR: results from a nationwide cross-sectional population-based survey

OBJECTIVE

Mumps-containing vaccine is currently not a component of the national immunization schedule in Lao People's Democratic Republic (PDR). Mumps itself is not a notifiable disease in the country and the seroprevalence of anti-mumps immunoglobulin G (IgG) in the general population is unknown. In this study, anti-mumps IgG was measured in 2058 blood samples to evaluate population immunity in the country.

RESULTS

The seroprevalence of anti-mumps IgG showed a gradual increase with increasing age, starting at 10.6% (95% CI 7.4-13.7) in participants aged 1-2 years, and almost plateaued at about 75% in individuals older than 11-12 years, though it still tended toward a small increase up to 89.6% (95% CI 86.6-92.6) in participants aged 40 years or older. Compared with the results of previous studies, this increase with increasing age is less marked and the plateau of anti-mumps seroprevalence is lower. We attribute this result mainly to the lower population density in Lao PDR.

Seroprevalence of Measles, Mumps, and Rubella Antibodies in College Students in Mumbai, India

Measles, Mumps, and Rubella (MMR) are vaccine preventable viral infections, which cause significant mortality and morbidity globally. Increased incidence rates of these infectious diseases are observed in young adults. Information on seroprevalence data on MMR in India is limited. The objective of this study was to determine the prevalence of IgG antibodies against MMR among young adults. This was a descriptive cross-sectional study involving 192 healthy college students from Maharshi Dayanand College, Mumbai. The project was approved by the Institutional Ethics Committee of Haffkine Institute. Between December 2012 and September 2013, blood samples were collected from individuals of age 18-23 years after obtaining written informed consent from them. The quantitative determination of IgG antibodies in serum specimens against MMR was determined using enzyme linked immunosorbent assay. Data on history of vaccination were also collected from participants. Among 192 healthy college students (age 18-23 years), MMR seroprevalence was 91%, 97%, and 88%, respectively. The overall seropositivity of MMR was 79%. The highest level of seronegativity was seen with regards to rubella-specific antibodies in 12% of cases. About 96% of the participants did not know about their vaccination history while none of the participants knew about their history of MMR infections. Despite unknown vaccination status, a majority of college students in our study were found seropositive for all three infections, which indicate natural boosting. However, the proportion of seronegativity for measles and rubella was relatively higher. Especially since the study population belonged to reproductive age group, there is a concern of congenital rubella syndrome in the offspring. Although a larger multicentric study is required to confirm the findings, the results indicate that a dose of measles-rubella (MR) vaccine should be offered to these college students.

Molecular biology, pathogenesis and pathology of mumps virus

Mumps is caused by the mumps virus (MuV), a member of the Paramyxoviridae family of enveloped, non-segmented, negative-sense RNA viruses. Mumps is characterized by painful inflammatory symptoms, such as parotitis and orchitis. The virus is highly neurotropic, with laboratory evidence of central nervous system (CNS) infection in approximately half of cases. Symptomatic CNS infection occurs less frequently; nonetheless, prior to the introduction of routine vaccination, MuV was a leading cause of aseptic meningitis and viral encephalitis in many developed countries. Despite being one of the oldest recognized diseases, with a worldwide distribution, surprisingly little attention has been given to its study. Cases of aseptic meningitis associated with some vaccine strains and a global resurgence of cases, including in highly vaccinated populations, has renewed interest in the virus, particularly in its pathogenesis and the need for development of clinically relevant models of disease. In this review we summarize the current state of knowledge on the virus, its pathogenesis and its clinical and pathological outcomes.

Effect of weather variability on the incidence of mumps in children: a time-series analysis

The increasing international interest in the potential health effects of climate change has emphasized the importance of investigations into the relationship between weather variability and infectious diseases. However, few studies have examined the impact of weather variability on mumps in children, despite the fact that children are considered particularly vulnerable to climate change. We acquired data about cases of mumps in children aged <15 years and weather variability in Fukuoka, Japan from 2000 to 2008, and then used time-series analyses to assess how weather variability affected mumps cases, adjusting for seasonal variations, inter-annual variations, and temporal variations of two large epidemics in 2001 and 2004-2005. The weekly number of mumps cases increased by 7·5% (95% CI 4·0-11·1) for every 1°C increase in average temperature and by 1·4% (95% CI 0·5-2·4) for every 1% increase in relative humidity. The percentage increase was greatest in the 0-4 years age group and tended to decrease with increasing age. The number of mumps cases in children increased significantly with increased average temperature and relative humidity.

Prevalence of IgG antibody against measles, mumps and rubella in bangladeshi children: a pilot study to evaluate the need for integrated vaccination strategy

The present study was carried out to determine the seroprevalence of IgG antibodies in Bangladeshi children against measles (irrespective of vaccination status), mumps and rubella (MMR) to assess strategic need of combined vaccination for these diseases. A total of 456 children of 1 month to 15 years, were studied. Serum IgG antibodies against MMR were measured by enzyme-linked immunosorbent assay (ELISA). By 3 months, protective IgG antibody level (>40 AU for measles and mumps and >15 IU/ml for rubella) for the diseases found to be between 50% and 80% among the studied children. Protective measles antibody (IgG) was not detected in all the children of 3-9 months and significant number of children between 9 months and 5 years were unprotected (87-65%; P < 0.001). Moreover, children of 3-15 months had no protective antibody level against mumps and significant number of children between 15 months and 5 years were unprotected (92-71%; P < 0.001). Between 5 and 15 years of age, significant number of children became protective (63-85%, P < 0.001). Although, a majority of children between 3 months and 5 years had shown to have no protective antibody against rubella (89-71%; P < 0.01-0.001) between >10 and 15 years 71% children had protective level of antibodies (P < 0.001). No significant difference was observed in antibody prevalence regarding socioeconomic classes, nutritional status and parental education. The data showed that: (i) a significant number of children remain unprotected against MMR in childhood and (ii) an extensive nationwide survey is required to suggest an integrated vaccination strategy in order to implement appropriate control measures of the three infectious diseases.

Seroepidemiological study of respiratory syncytial virus in São Paulo state, Brazil

Transmission of respiratory syncytial virus is thought to be highly seasonal based on reported clinical cases, although transmission resulting in mild disease in all age groups has been little studied. This has been investigated in a seroepidemiological survey using sera from São Paulo, Brazil. Seroprevalence was found to increase rapidly with age, reaching over 90% by three years of age. This is typical of viral infections, which produce life-long immunity following primary infection. One-hundred percent seropositivity was attained by five years of age and maintained throughout adulthood, whereas mean antibody titers continued to increase with age. The mean duration of maternal antibodies was estimated to be 3.3 months with antibody decay demonstrated in paired samples from infants. The results are discussed in relation to possible mechanisms generating such a profile.

The epidemiology of varicella-zoster virus infections

Historically, varicella has been a disease predominantly affecting preschool and school-aged children in the United States. The live attenuated varicella vaccine was licensed in this country in 1995 and has been recommended for routine use in immunization of children 12 to 18 months of age. As an increasing proportion of the children in the United States are protected from varicella by vaccination, changes in the current epidemiology of the disease are anticipated. This article reviews the current epidemiology of VZV infection and outlines issues related to possible changes in varicella epidemiology that may follow widespread use of the live varicella (Oka) vaccine.

The age of infection with varicella-zoster virus in St Lucia, West Indies

Sera from an age-stratified sample of 1810 people from the Caribbean island of St Lucia were tested for antibodies against varicella-zoster virus. The results indicate that very few infections occur in childhood, which agrees with clinical survey data from other tropical countries, but contrasts with the observed high case rate in children in temperate countries. The alternative hypotheses which may explain these results are discussed, and it is suggested that high ambient temperatures interfere with the transmission of the virus. Irrespective of the cause, the pattern of varicella incidence observed has important implications for any vaccination policy adopted in tropical countries.

Serological study of the epidemiology of mumps virus infection in north-west England

Serum samples from individuals of a wide age range, collected in northwest England in 1984 and 1986, provide the basis for an analysis of the epidemiology of mumps virus infection. A radial haemolysis test yielding quantitative antibody measurements was used to screen samples for mumps-specific IgG. Analyses of resultant age-seroprevalence profiles, using statistical models, revealed an age-related pattern in the rate of infection per susceptible similar to that observed for other childhood infections. This rate, or force of infection, was low in young children, high in older children, and low in adults. In addition, the serological surveys provide evidence for time-dependent changes (both epidemic and longer-term) in the rate of mumps virus transmission. The longer-term changes, reflected in the pattern of the age-acquisition of specific antibodies, are supported by evidence from case notification data. The implications of temporal changes in incidence to the interpretation and design of serological surveys are considered.