Seroprevalence of measles, mumps, rubella, and varicella zoster virus antibodies among healthcare students: analysis of vaccine efficacy and cost-effectiveness / Seroprevalencia de anticuerpos contra el sarampión, las paperas, la rubéola y el virus de la varicela zoster entre estudiantes de enfermería: análisis de coste-efectividad de la vacuna

INTRODUCTION: The aims of this study are to determine the seroprevalence for measles, mumps, rubella, and varicella zoster virus (VZV) in a cohort of nursing students, to evaluate vaccination response rates of nonimmune students, and to calculate the cost of vaccinating students based on seroprevalence screening. MATERIAL AND METHODS: A cross-sectional study was conducted August 2015-November 2016 among 326 healthy nursing students aged 14.1-18.1 years. Serum IgG antibodies were measured by ELISA. Results were analyzed by the Chi-square test; a p-value of < 0.05 was considered statistically significant. RESULTS: The number of seropositive participants (%) was 308 (94.5%) for rubella, 295 (90.5%) for VZV, 244 (74.9%) for measles, and 219 (67.2%) for mumps. A significant correlation was found between measles IgG and age. A relationship was also observed between VZV IgG and kindergarten attendance. Response rates to measles, rubella, VZV, and mumps vaccination were 96%, 92.3%, 87.5%, 78.8%, respectively. The total cost of vaccination after IgG screening was less than vaccination without screening. CONCLUSIONS: In this study, participants' immunity to measles and VZV was low. Prevaccination serological screening was cost-effectiveness method for preventing measles, mumps, rubella, and varicella infections. We believe that administering booster measles, mumps, and rubella (MMR) vaccine doses or developing a special MMR vaccination strategy for at-risk groups may prevent MMR outbreaks

OBJETIVOS: Los trabajadores sanitarios con frecuencia están expuestos a agentes infecciosos mientras realizan sus tareas. Los objetivos de este estudio son determinar la sero-prevalencia del virus de sarampión, paperas, rubeola y varicela zoster (VZV) en un grupo de estudiantes de enfermería, evaluar las tasas de respuesta de vacunación de estudiantes no inmunes y calcular el coste de vacunación de los estudiantes basándose en la detección de seroprevalencia. MATERIAL Y MÉTODOS: Se realizó un estudio transversal de agosto de 2015 a noviembre de 2015 entre 326 estudiantes de enfermería sanos de 14,1 a 18,1 años. Los anticuerpos IgG séricos se midieron por ELISA. Los resultados fueron analizados mediante la prueba de Chi-cuadrado. RESULTADOS: El número de participantes seropositivos (%) fue de 308 (94,5%) para la rubeola, 295 (90,5%) para el VZV, 244 (74,9%) para el sarampión y 219 (67,2%) para las paperas. Se encontró una correlación significativa entre la IgG del sarampión y la edad. También se observó una relación entre VZV IgG y asistencia a guardería. Las tasas de respuesta a la vacunación contra el sarampión, la rubeola, el VZV y las paperas fueron del 96%, 92,3%, 87,5%, 78,8%, respectivamente. El coste total de la vacunación después de la detección de IgG fue menor que la vacunación sin la detección. CONCLUSIONES: En este estudio, la inmunidad de los participantes al sarampión y al VZV fue baja. La detección serológica previa a la vacunación fue un método de coste-efectividad para prevenir las infecciones por sarampión, paperas, rubeola y varicela. Creemos que la administración de una dosis de la vacuna triple vírica de refuerzo o el desarrollo de una estrategia especial de vacunación dosis de la vacuna triple vírica para grupos en riesgo puede prevenir los brotes de de sarampión, paperas y rubeola

Seroprevalence of measles, mumps, rubella, and varicella zoster virus antibodies among healthcare students: analysis of vaccine efficacy and cost-effectiveness.

OBJECTIVE: The aims of this study are to determine the seroprevalence for measles, mumps, rubella, and varicella zoster virus (VZV) in a cohort of nursing students, to evaluate vaccination response rates of nonimmune students, and to calculate the cost of vaccinating students based on seroprevalence screening. METHODS: A cross-sectional study was conducted August 2015-November 2016 among 326 healthy nursing students aged 14.1-18.1 years. Serum IgG antibodies were measured by ELISA. Results were analyzed by the Chi-square test; a p-value of < 0.05 was considered statistically significant. RESULTS: The number of seropositive participants (%) was 308 (94.5%) for rubella, 295 (90.5%) for VZV, 244 (74.9%) for measles, and 219 (67.2%) for mumps. A significant correlation was found between measles IgG and age. A relationship was also observed between VZV IgG and kindergarten attendance. Response rates to measles, rubella, VZV, and mumps vaccination were 96%, 92.3%, 87.5%, 78.8%, respectively. The total cost of vaccination after IgG screening was less than vaccination without screening. CONCLUSIONS: In this study, participants' immunity to measles and VZV was low. Prevaccination serological screening was cost-effectiveness method for preventing measles, mumps, rubella, and varicella infections. We believe that administering booster measles, mumps, and rubella (MMR) vaccine doses or developing a special MMR vaccination strategy for at-risk groups may prevent MMR outbreaks.

Seroprevalence of measles, mumps & rubella antibodies among 5-10 years old children in north India.

Background & objectives: : Globally, there is an effort to eliminate the measles and control rubella as these diseases lead to considerable morbidity and mortality especially among under-five children and are important public health problems. This study was aimed to estimate the seroprevalence of measles, mumps and rubella (MMR) antibodies among children of age 5-10 yr in Chandigarh, north India, to provide evidence on prevalent immunity levels. Methods: : This cross-sectional study was conducted in Chandigarh, among 196 randomly selected healthy children (5-10 yr), who received either one or two doses of measles or MMR combination vaccine. Socio-economic background and immunization history were recorded. Blood sample (2 ml) was collected to estimate the MMR IgG antibody titres by using ELISA kits. Results: : Protective seroprevalence of MMR antibodies was 40.8, 75.5 and 86.2 per cent, respectively. The geometric mean titres of MMR IgG antibodies in the study children were 11.3, 50.6 and 54.3 international units (IU)/ ml, respectively. The proportion of seroprotected children for measles was significantly higher among those who had received two or more doses (46.4%) of measles vaccine compared to those who had received single dose (35.6%) (P <0.001). About 16 per cent of children had received single dose of MMR vaccine. Among these, 71.4 and 100 per cent were seroprotected against mumps and rubella, respectively. Interpretation & conclusions: : A large proportion of children aged 5-10 yr lacked protective immunity against measles (60%); about one-fourth (15-25%) were susceptible to infection with mumps and rubella virus. Mumps vaccination may be considered to be included in National Immunization Schedule for children with periodic serosurveillance.

Sample size calculation for estimating key epidemiological parameters using serological data and mathematical modelling.

BACKGROUND: Our work was motivated by the need to, given serum availability and/or financial resources, decide on which samples to test in a serum bank for different pathogens. Simulation-based sample size calculations were performed to determine the age-based sampling structures and optimal allocation of a given number of samples for testing across various age groups best suited to estimate key epidemiological parameters (e.g., seroprevalence or force of infection) with acceptable precision levels in a cross-sectional seroprevalence survey. METHODS: Statistical and mathematical models and three age-based sampling structures (survey-based structure, population-based structure, uniform structure) were used. Our calculations are based on Belgian serological survey data collected in 2001-2003 where testing was done, amongst others, for the presence of Immunoglobulin G antibodies against measles, mumps, and rubella, for which a national mass immunisation programme was introduced in 1985 in Belgium, and against varicella-zoster virus and parvovirus B19 for which the endemic equilibrium assumption is tenable in Belgium. RESULTS: The optimal age-based sampling structure to use in the sampling of a serological survey as well as the optimal allocation distribution varied depending on the epidemiological parameter of interest for a given infection and between infections. CONCLUSIONS: When estimating epidemiological parameters with acceptable levels of precision within the context of a single cross-sectional serological survey, attention should be given to the age-based sampling structure. Simulation-based sample size calculations in combination with mathematical modelling can be utilised for choosing the optimal allocation of a given number of samples over various age groups.

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.

Mumps outbreak investigation in Jaisalmer, Rajasthan, India, June-September 2016.

Mumps, a vaccine-preventable disease, cause inflammation of salivary glands and may cause severe complications, such as encephalitis, meningitis, deafness, and orchitis/oophoritis. In India, mumps vaccine is not included in the universal immunization program and during 2009 to 2014, 72 outbreaks with greater than 1500 cases were reported. In August 2016, a suspected mumps outbreak was reported in Jaisalmer block, Rajasthan. We investigated to confirm the etiology, describe the epidemiology, and recommend prevention and control measures. We defined a case as swelling in the parotid region in a Jaisalmer block resident between 23 June 2016 and 10 September 2016. We searched for cases in health facilities and house-to-house in affected villages and hamlets. We tested blood samples of cases for mumps immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA). We found 162 cases (60% males) with a median age of 9.4 years (range: 7 month-38 years) and 65 (40%) were females. Symptoms included fever (70%) and bilateral swelling in neck (65%). None of them were vaccinated against mumps. Most (84%) cases were school-going children (3-16 years old). The overall attack rate was 2%. Village A, with two hamlets, had the highest attack rate (hamlet 1 = 13% and hamlet 2 = 12%). School A of village A, hamlet 1, which accommodated 200 children in two classrooms, had an attack rate of 55%. Of 18 blood samples from cases, 11 tested positive for mumps IgM ELISA. This was a confirmed mumps outbreak in Jaisalmer block that disproportionately affected school-going children. We recommended continued surveillance, 5-day absence from school, and vaccination.

Seroprevalence and Determinants Associated with Mumps Antibodies after 20 Years of MMR Vaccination in Urban Area of Shanghai, China.

A resurgence of the mumps epidemic in highly vaccinated populations has occurred in recent years in many countries. This study aimed to evaluate the seroprevalence to mumps in urban areas of Shanghai, where a measles-mumps-rubella (MMR) vaccination had been implemented for 20 years. Mumps IgG antibodies were tested in 2662 residual sera from all ages in an urban area of Shanghai. A linear regression method was performed to assess the persistence of mumps antibodies after MMR vaccination. A logistic regression method was used to analyze the variables associated with seronegative sera. The overall age- and gender-adjusted seroprevalence of mumps antibodies reached 90% (95% CI: 90.0⁻90.2). The antibody concentration declined significantly in the first eight years after the second dose of MMR. The multivariate analysis identified that males, age groups, especially 17⁻19 years and no dose of vaccination, as well as one dose of vaccination, as factors associated with an increased risk of seronegative sera. A high seroprevalence to mumps has been achieved in the urban areas of Shanghai. A declining antibody level of mumps after the second dose of MMR may put a potential risk of recurrence of mumps. The two-dose MMR vaccine schedule is superior to one-dose schedule for mumps control.

Mumps epidemiology in Cuba between 2004 and 2015.

Vaccination with the measles, mumps and rubella vaccine decreased the mumps incidence in Cuba, but in 2006 and 2007 an outbreak with more than 1000 laboratory confirmed cases occurred, mainly among high school and university students. The objective of the study was to investigate mumps epidemiology in Cuba between 2004 and 2015 and provide an in-depth laboratory characterization of selected samples from mumps patients. Samples from 116 cases (throat swabs, urines, paired acute and convalescent serum samples) were tested for mumps-specific IgM antibodies by ELISA, in a hemagglutination inhibition assay (HIA) or by RT-PCR. IgM antibodies were found in 80.2% of cases. 48.3% of first sera were positive, 30 of which were collected within two days after symptom onset. Testing of all 116 paired sera by HIA showed seroconversion in 55.2% individuals and an at least fourfold increase in antibodies in 44.8% of cases. In 18 out of the 111 vaccinated people (16.2%) no IgM antibodies were detected, neither in the acute nor the convalescent sera, but 14 of them showed seroconversion by HIA and 4 had an at least fourfold increase of hemagglutinin antibody titers. In the RT-PCR, 23 acute phase sera, 4 throat swabs and 5 urines were positive. Detection of mumps-specific IgM antibodies by ELISA and additional diagnostic methods may be required in settings with high vaccination coverage rates.

Serological diagnosis of mumps: Value of the titration of specific IgG. / Diagnóstico serológico de parotiditis epidémica: valor de la titulación de IgG específica.

INTRODUCTION: The aim of this study was to evaluate a cut-off point of the titration of IgG by ELISA in the diagnosis of mumps. METHODS: A study was made of serum samples from 85 mumps cases (confirmed by PCR in saliva) and 2,351 controls of the general population of the Region of Madrid. RESULTS: The IgM detection was positive in 21 cases (sensitivity of 24.7%). The best cut-off point corresponded to IgG titres ≥4,900 (sensitivity of 64.7% and specificity of 86.1%). Among 42 patients immunised with at least one dose of measles mumps, rubella vaccine IgM was detected in 4 cases. However, the detection of IgG ≥4,900 was positive in 29 (sensitivity of 69.0%). CONCLUSIONS: An IgG result of ≥4.900 was almost 5 times more probable in a patient with mumps than in a non-infected patient. The detection of high titres of IgG against mumps could improve the IgM results in vaccinated people.

Serological survey of mumps antibodies in adults in the Czech Republic and the need for changes to the vaccination strategy.

Mumps outbreaks, especially in adolescents and young adults, have been reported in the Czech Republic. The aim of the presented study was to determine the seroprevalence of specific IgG antibodies against mumps in the adult population of the Czech Republic. The study was designed as a multicenter serological survey of adults aged 18 years and over. Specific IgG antibodies against mumps were detected in blood samples using an enzyme-linked immunosorbent assay (ELISA). A total of 1,911 serum samples were examined. The overall seropositivity reached 55.3%. In individual age groups, the highest seropositivity 63% (63.5-65.2%) was recorded in adults aged 40 years and over; the lowest seropositivity was found in adults aged 18-29 years (27.4%). The difference in seropositivity rate between the 18-29 years age group and the 40 years and over age groups was statistically significant (p < 0.001). Only the 18-29 years age group included both vaccinated and unvaccinated (born in the pre-vaccine era) individuals. In vaccinated individuals, seropositivity was reported in only 19.1% of persons; in unvaccinated individuals, seropositivity reached 48.2%. Our results demonstrate the long-term persistence of antibodies following natural infection and the decrease in seropositivity that occurs after vaccination over time. This immunity waning may account for the higher susceptibility of adolescents and young adults to mumps. Therefore, the current vaccination program in the Czech Republic could be considered as less effective. It will be modified with the shifting of the second dose of vaccine from two years of age to the preschool age.

Anti-rubella, Mumps and Measles IgG Antibodies in Medical Students of Tehran University.

Measles, mumps and rubella are viral infectious diseases that may result in serious complications. Since the production of vaccines, the number of cases of these diseases has been dropped. Nevertheless, these infectious diseases are still one of the major health problems in developing countries. In this study, in order to evaluate the protective responses against measles, mumps and rubella, the level and avidity of virus-specific IgG antibodies were measured in 53 medical students of Tehran University, aged between 20-30 years. Except for mumps vaccine, all the students had been vaccinated against measles and rubella according to Iran's nationwide mass vaccination protocol for all persons aged 5-25 in 2003. Our results showed that 96.2% of the volunteers had a protective level (>15 IU/ml) of IgG against rubella, 79.2% had a protective level (>11 IU/ml) of IgG against measles and 64.16% had a protective level (>11 IU/ml) of IgG against mumps. Over ten years after nationwide measles-rubella vaccination campaign, most young adults aged 20-30 had protective levels of humoral immunity against measles and rubella. However, Iranian young population is still unvaccinated against mumps, and therefore relatively large number of young adults had no protective level of IgG against it. This finding may be due to reduction in circulating of wild strain. We recommend screening of medical students for immunity against infectious agents such as measles, mumps, rubella, because they are at a high risk of these infectious agents.

Virus genotypes and responses of serum-specific antibodies in children with primary mumps and mumps reinfection.

BACKGROUND: Research on children with mumps reinfection after natural infection is limited; there are currently no studies on virus-specific antibody responses in paired sera or genotyping of isolated viruses. METHODS: This study included 281 children (147 boys and 134 girls, age: 1.2-15.9 y) with primary mumps (240), mumps reinfection after natural infection (9), mumps after previous vaccination (26), and vaccine-associated mumps (6). We measured mumps-specific serum antibodies and analyzed isolated virus genes. RESULTS: During acute illness, series-specific IgM and IgG titers exceeded cutoff values in 240 and 232 children with primary mumps, respectively. During convalescence, IgM antibodies were positive in seven and negative in two of nine children with mumps reinfection occurring after natural infection; among 26 previously vaccinated children, 13 were positive and 13 negative. Mumps viruses were isolated from viral cultures from 42 of the 51 children. Except for 6 vaccine-associated cases, all remaining 36 cases of isolated mumps virus were identified as genotype G. CONCLUSION: These results suggest that measurement of IgM antibody on any day of acute illness may be indicative of primary mumps but may be inconsistent for diagnosing mumps reinfection after natural infection or previous vaccination.

Cellphone-Based Hand-Held Microplate Reader for Point-of-Care Testing of Enzyme-Linked Immunosorbent Assays.

Standard microplate based enzyme-linked immunosorbent assays (ELISA) are widely utilized for various nanomedicine, molecular sensing, and disease screening applications, and this multiwell plate batched analysis dramatically reduces diagnosis costs per patient compared to nonbatched or nonstandard tests. However, their use in resource-limited and field-settings is inhibited by the necessity for relatively large and expensive readout instruments. To mitigate this problem, we created a hand-held and cost-effective cellphone-based colorimetric microplate reader, which uses a 3D-printed opto-mechanical attachment to hold and illuminate a 96-well plate using a light-emitting-diode (LED) array. This LED light is transmitted through each well, and is then collected via 96 individual optical fibers. Captured images of this fiber-bundle are transmitted to our servers through a custom-designed app for processing using a machine learning algorithm, yielding diagnostic results, which are delivered to the user within ∼1 min per 96-well plate, and are visualized using the same app. We successfully tested this mobile platform in a clinical microbiology laboratory using FDA-approved mumps IgG, measles IgG, and herpes simplex virus IgG (HSV-1 and HSV-2) ELISA tests using a total of 567 and 571 patient samples for training and blind testing, respectively, and achieved an accuracy of 99.6%, 98.6%, 99.4%, and 99.4% for mumps, measles, HSV-1, and HSV-2 tests, respectively. This cost-effective and hand-held platform could assist health-care professionals to perform high-throughput disease screening or tracking of vaccination campaigns at the point-of-care, even in resource-poor and field-settings. Also, its intrinsic wireless connectivity can serve epidemiological studies, generating spatiotemporal maps of disease prevalence and immunity.

[The multiplex method of estimation of humoral immunity to vaccine regulated childhood infections].

The goal of this work was to present the results of the laboratory tests of the multiplex dot immunoassay method using protein microarray for complex estimation of humoral immunity to measles, mumps, and rubella viruses. It was shown that the obtained results were in a good agreement with data of commercial monospecific ELISA kits. The developed method is fast, requires fewer resources, and may be used in the field.

[Contribution of the detection of IgA antibodies to the laboratory diagnosis of mumps in the population with a high vaccination coverage]. / Prínos stanovení protilátek IgA pro laboratorní diagnostiku príusnic ve vysoce proockované populaci.

STUDY OBJECTIVE: Serological diagnosis of epidemic mumps can be difficult in vaccinated persons, particularly due to the absence of specific IgM antibodies. The aim was to find whether adding the detection of IgA antibodies to the currently used routine serological diagnosis of mumps (detection of IgM and IgG antibodies in an acute serum sample) would make the serological diagnosis of mumps more effective in a population with a high vaccination coverage. At the same time, ELISA kits for the detection of early IgA and IgM antibodies against the mumps virus were compared and statistical analysis of the results was performed. MATERIAL AND METHODS: Sixty-four acute sera from patients with laboratory confirmed diagnosis of mumps were included in the study. Clinical specimens were collected at the onset of clinical symptoms. To test the sera, the MASTAZYME ELISA Mumps IgA kit (MAST DIAGNOSTICA, Germany) with the MASTSORB sorbent (RF and IgG) and Enzygnost Anti-Parotitis-Virus/IgM kit (Siemens, Germany) were used. A panel of 121 acute sera with no epidemiological link to mumps virus served as specificity controls for the IgA assay. The epidemiological data were derived from the EPIDAT system. The level of agreement was assessed using the McNemara test and Cohen's coefficient kappa. The Stata 9.2 software (Stata Corp LP, College Station, USA) was used for statistical analysis. RESULTS: The detection of IgA and IgM antibodies against the mumps virus yielded concordant results in 50/64 acute sera, 32 positive and 18 negative, i.e. an agreement of 78.12 %. Of the remaining 14 samples, 13 were only IgA positive and one was only IgM positive. The controls showed non-specific IgA positivity in 5/121 samples which indicates a 96% specificity. CONCLUSION: The absence of specific IgM antibodies against mumps virus is relatively often seen in vaccinated indivi-duals; nevertheless, the test is routinely used in patients with suspected active infection. The test for IgA antibodies, which is not routinely performed, significantly increased the detection rate of the disease. Based on the results of the present study, it can be concluded that the combination of the anti-mumps IgM and IgA assays increased the effectiveness of the serological diagnosis at the onset of clinical symptoms from less than 52% to nearly 72%.

Elevation of Serum Levels of High-Sensitivity Procalcitonin, C-reactive Protein, and Amyloid A in a Prepubertal Child with Mumps Orchitis.

BACKGROUND: Serum CRP concentrations are significantly elevated at the acute phase in patients with mumps orchitis, but little is known currently about other inflammatory biomarkers. METHODS: We report the measurements of serum inflammatory biomarkers [high-sensitivity procalcitonin (hs-PCT), C-reactive protein (CRP) and amyloid A] in a child with mumps orchitis. RESULTS: The patient's serum levels of CRP, hs-PCT, and amyloid A were highly increased at the acute phase, but returned to normal levels at convalescence. CONCLUSIONS: This case suggests that hs-PCT and amyloid A may not be useful for distinguishing between mumps orchitis accompanied by highly elevated serum concentrations of CRP and systemic bacterial infections.

Development of a simplified and convenient assay for cell-mediated immunity to the mumps virus.

Because methods for measuring cell-mediated immunity (CMI) to the mumps virus are expensive, time-consuming, and technically demanding, the role of CMI in mumps virus infection remains unclear. To address this issue, we report here the development of a simplified method for measuring mumps virus-specific CMI that is suitable for use in diverse laboratory and clinical settings. A mumps vaccine was cultured with whole blood, and interferon (IFN)-γ released into the culture supernatant was measured using an enzyme-linked immunosorbent assay. IFN-γ production in blood from vaccinated subjects markedly increased in response to the vaccine and decreased before the antibody titer decreased in some cases, suggesting that this assay may be used as a simple surrogate method for measuring CMI specific for the mumps virus.

High prevalence of mumps in Lao People's Democratic Republic.

In the Lao People's Democratic Republic (PDR), mumps is not a notifiable disease and mumps vaccine is currently not included in the routine childhood immunization programme. In order to assess the burden of disease, we investigated the seroprevalence of mumps-specific IgG antibodies across four provinces. In addition, we genetically characterized mumps viruses from the past 3 years from several outbreaks and single cases. Blood and/or throat swabs from suspected cases were investigated for specific IgM antibodies or viral RNA. Mumps cases occurred between March and November in 2011-2013 and 5- to 15-year-olds were most affected. Four sequences from an outbreak in the north of Lao PDR in 2011 were identical and belonged to genotype G. Eight sequences from two outbreaks and two individual cases from 2012 and 2013 belonged to genotype J. In addition, sera collected from 2379 healthy infants and school pupils aged between 9 months and 19 years and from pregnant women aged between 16 and 46 years were investigated for mumps-specific IgG. Overall, 58.2% were positive, 39.5% were negative and the remaining 2.3% were equivocal. The seropositivity increased with age, with the lowest percentage found in <1-year-old infants (9.1%) and the highest in the cohort of pregnant women (69.2%). More female subjects than male subjects were seropositive (60.4 vs. 54.9%). There were some differences between the locations. Mumps should be a notifiable disease in Lao PDR in order to get more accurate case numbers and cost estimates for public health-care, and vaccination of children and high-risk groups should be considered.

IL-6 and IFNγ are elevated in severe mumps cases: a study of 960 mumps patients in China.

INTRODUCTION: Mumps is a common infectious disease. Epidemics of mumps are reported globally every year and represent a threat to public health, especially in China and other developing countries. METHODOLOGY: Clinical and laboratory findings of 960 mumps patients admitted to Beijing You'an Hospital, China, between January 2010 and December 2012 were collected and analyzed. Patients with isolated complication were selected and grouped as aseptic meningitis/encephalitis (AME) patients (n = 156) and Orchitis patients (n = 72). One hundred and fifty patients without complication were grouped as control. Levels of T cell subtypes and 8 serum cytokines were also tested. RESULTS: Majority of mumps patients were male (76.3%) and younger than 17 years old (76.2%). AME was complicated in 41.6% of mumps cases, and orchitis was in 21.3% (64.7% were left-sided). Unvacinated patients had more chance to have AME or orchitis (p = 0.034 and 0.027). The rates of AME and orchitis in mumps patients rapidly increased during the last three years. No laboratory findings were associated with AME or orchitis (all p > 0.05). Serum IL-10 level was elevated in almost all patients. IL-6 and IFNγ levels were correlated with AME (p = 0.025 and p = 0.018). Their levels peaked at day one after admission, and started to decline thereafter. CONCLUSIONS: This study suggests that the incidence of serious complications has become more common in recent years, moreover IL-6 and IFNγ may possibly be used as early serum markers for identifying patients with risk of developing complications in mumps.

Assessing mumps outbreak risk in highly vaccinated populations using spatial seroprevalence data.

Mumps is a potentially severe viral infection. The incidence of mumps has declined dramatically in high-income countries since the introduction of mumps antigen-containing vaccines. However, recent large outbreaks of mumps in highly vaccinated populations suggest waning of vaccine-induced immunity and primary vaccine failure. In this paper we present a simple method for identifying geographic regions with high outbreak potential, demonstrated using 2006 mumps seroprevalence data from Belgium and Belgian vaccination coverage data. Predictions of the outbreak potential in terms of the effective reproduction number in future years signal an increased risk of new mumps outbreaks. Literature reviews on serological information for both primary vaccine failure and waning immunity provide essential information for our predictions. Tailor-made additional vaccination campaigns would be valuable for decreasing local pockets of susceptibility, thereby reducing the risk of future large-scale mumps outbreaks.