Pediatricians' Knowledge and Practices Related to Mumps Diagnosis and Prevention.

OBJECTIVES: To assess pediatricians' mumps knowledge and testing practices, to identify physician and practice characteristics associated with mumps testing practices, and to assess reporting and outbreak response knowledge and practices. STUDY DESIGN: Between January and April 2020, we surveyed a nationally representative network of pediatricians. Descriptive statistics were generated for all items. The χ2 test, t tests, and Poisson regression were used to compare physician and practice characteristics between respondents who would rarely or never versus sometimes or often/always test for mumps in a vaccinated 17-year-old with parotitis in a non-outbreak setting. RESULTS: The response rate was 67% (297 of 444). For knowledge, more than one-half of the pediatricians responded incorrectly or "don't know" for 6 of the 9 true/false statements about mumps epidemiology, diagnosis, and prevention, and more than one-half reported needing additional guidance on mumps buccal swab testing. For testing practices, 59% of respondents reported they would sometimes (35%) or often/always (24%) test for mumps in a vaccinated 17-year-old with parotitis in a non-outbreak setting; older physicians, rural physicians, and physicians from the Northeast or Midwest were more likely to test for mumps. Thirty-six percent of the pediatricians reported they would often/always report a patient with suspected mumps to public health authorities. CONCLUSIONS: Pediatricians report mumps knowledge gaps and practices that do not align with public health recommendations. These gaps may lead to underdiagnosis and underreporting of mumps cases, delaying public health response measures and contributing to ongoing disease transmission.

Mumps Orchitis: Clinical Aspects and Mechanisms.

The causative agent of mumps is a single-stranded, non-segmented, negative sense RNA virus belonging to the Paramyxoviridae family. Besides the classic symptom of painfully swollen parotid salivary glands (parotitis) in mumps virus (MuV)-infected men, orchitis is the most common form of extra-salivary gland inflammation. Mumps orchitis frequently occurs in young adult men, and leads to pain and swelling of the testis. The administration of MuV vaccines in children has been proven highly effective in reducing the incidence of mumps. However, a recent global outbreak of mumps and the high rate of orchitis have recently been considered as threats to male fertility. The pathogenesis of mumps orchitis remains largely unclear due to lack of systematic clinical data analysis and animal models studies. The alarming increase in the incidence of mumps orchitis and the high risk of the male fertility have thus become a major health concern. Recent studies have revealed the mechanisms by which MuV-host cells interact and MuV infection induces inflammatory responses in testicular cells. In this mini-review, we highlight advances in our knowledge of the clinical aspects and possible mechanisms of mumps orchitis.

The estimated impact of decreased childhood vaccination due to COVID-19 using a dynamic transmission model of mumps in Japan.

The exact impact of the decline in childhood vaccination coverage during COVID-19 outbreak has not been estimated for any vaccine-preventable diseases. Our objective was to evaluate the impact of decreased mumps vaccination due to COVID-19 on the disease burden of mumps in Japan. Using a previously validated dynamic transmission model of mumps infection in Japan, the incidence rate of mumps over the next 30 y since July 2020 was estimated. The estimated average incidences were 269.1, 302.0, and 455.4/100,000 person-years in rapid recovery, slow recovery, and permanent decline scenarios. Compared with the rapid recovery scenario, the incremental number of mumps cases, total costs, and QALYs loss over the next 30 y were 6.53 million cases, 2.63 billion USD, and 49,246 for the permanent decline scenario, respectively. In conclusion, the persistent decline of mumps vaccination rate as an impact of COVID-19 causes a significant incremental disease burden of mumps, which is consistent irrespective of the possible decline of transmission rate of mumps infection, unless the rapid recovery of coverage rate is achieved. The immediate measures to advocate the vaccination program is essential to mitigate the incremental disease burden in the COVID-19 period.

Effect of change in cell substrate on the critical quality attributes of L-Zagreb Mumps vaccine manufactured using parallel plate bioreactor.

Leningrad-Zagreb strain of mumps vaccine virus was grown on two different cell substrates viz. MRC-5 cells and Vero cells besides its original cell substrate i.e. Chicken Embryo Cells. Homogeneous virus pools prepared from each set of experiments were then lyophilized as per standard in-house protocol. Critical Quality Attributes (CQAs) such as the titer of the bulk vaccine and potency and stability of the lyophilized vaccine were then estimated using the CCID50 method to understand the lyophilization losses and thermal losses respectively in the vaccine. Another CQA viz. the genetic homogeneity of the vaccine was also tested using the single base extension method for identifying the nucleotides present at the three known locations of single nucleotide polymorphism (SNP). Comparison of CQA results across different cell substrates indicated encouraging results for Vero cell grown L-Zagreb virus compared to the MRC-5 cells grown L-Zagreb mumps virus. Significant improvement in productivity was also observed in the dynamic culture conditions compared to the static culture conditions. Progressive work in this research area can lead to development of a cGMP manufacturing process for mumps vaccine with easy scale up potential in future.

Cases of aseptic meningitis after vaccination against mumps in Russia (2009-2019).

OBJECTIVES: Mumps is a highly contagious viral infection prevented by immunization with live attenuated vaccines. Mumps vaccines have proven to be safe and effective; however, rare cases of aseptic meningitis (AM) can occur after vaccination. The range of meningitis occurrence varies by different factors (strain, vaccine producer, and so on). Monovaccines or divaccines (mumps-measles vaccine), prepared from the strain Leningrad-3 (L-3), are used in Russia. Meningitis occurrence after vaccination has been established previously as very low. Nevertheless, with the number of children being vaccinated every year, vaccine-associated AM cases still occur. There is no official statistics on AM incidence after mumps vaccines, and information on AM features as an adverse event of mumps vaccination is limited and mostly devoted to vaccines, prepared from strains other than L-3. STUDY DESIGN: The study included patients with AM who were vaccinated against mumps in the previous 30 days before the present disease onset during 2009-2019. METHODS: Patients admitted to Infectious Clinical Hospital No. 1, Moscow, Russia, with AM were observed by a pediatrician and were screened for etiological agents of meningitis. RESULTS: Seven patients were enrolled, and clinical features and the course of infection are presented. CONCLUSIONS: Detection of only 7 cases of AM associated with mumps vaccination during the 10-year period supports very low occurrence of this adverse event after immunization with the L-3 strain-based mumps vaccines. Nevertheless, the annual number of AM cases that occur after mumps vaccination remains unknown and poorly diagnosed in practice because of the low awareness of physicians of this adverse reaction. Detection and objective coverage of such cases can lead to a weakening of 'antivaccination' moods in a society and to restoration of confidence in the healthcare system.

Waning immunity and re-emergence of measles and mumps in the vaccine era.

Vaccine-preventable diseases (VPD) including measles and mumps have been re-emerging in countries with sustained high vaccine coverage. For mumps, waning immunity has been recognized as a major contributor to recent outbreaks. Although unvaccinated individuals account for most cases in recent measles outbreaks, the role of immune waning remains unclear. Accumulating serological and epidemiological evidence suggests that natural immunity induced by infection may be more durable compared to vaccine-induced immunity. As the proportion of population immunity via vaccination gradually increases and boosting through natural exposures becomes rare, risk of outbreaks may increase. Mechanistic insights into the coupled immuno-epidemiological dynamics of waning and boosting will be important to understand optimal vaccination strategies to combat VPD re-emergence and achieve eradication.

Assessing the Changes of Mumps Characteristics with Different Vaccination Strategies Using Surveillance Data: Importance to Introduce the 2-Dose Schedule in Quzhou of China.

BACKGROUND: From 2005 to 2016, the prevention and control of mumps in China have undergone three stages of transition. These include the use of MuCV as a self-supported vaccine, the introduction of one-dose MMR to the Expanded Program on Immunization (EPI), and the administration of two-dose MuCV following supplementary immunization activities (SIAs) using MM. Here, using surveillance data, we assessed the epidemiology of mumps during the three stages. METHODS: Children in Quzhou of China born from 2005 to 2016 and registered in the Zhejiang Provincial Immunization Information System (ZJIIS) were included. We analyzed the epidemic data and calculated incidence and MuCV coverage via birth cohorts. RESULTS: The average incidence of mumps in 2005-2006, 2007-2010, and 2011-2016 was 51.57, 41.02, and 12.53 per 100,000 individuals, respectively. The highest incidence was in children aged 6-14 years from 2005-2016, of which the majority were school students (67.84%). Approximately 90% of the reported outbreaks occurred in school children (primary school/middle school). The seasonal characteristics of mumps were less obvious from 2011 to 2016. The coverage of one-dose MMR in the 2005 birth cohort was 71.38%. For the 2006-2010 birth cohort, the coverage of one-dose MuCV was 96.82% and the coverage of two-dose MuCV was 17.68%. The children born from 2011 to 2016 were only free vaccinated with MMR; the coverage of one-dose MuCV was 99.10%. The mumps incidence in the three birth cohorts significantly declined (X 2 = 805.90, P < 0.001 for trend). Except the children less than two years old, the mumps incidence for the children born from 2006 to 2010 was higher than that for the children born from 2011 to 2016. CONCLUSION: The mumps incidence significantly declined following the introduction of one-dose MMR. The SIA using MM led to a rapid reduction of mumps cases. Therefore, we recommend a two-dose MuCV routine immunization schedule and improved vaccination coverage.

Mumps in Poland in 2018.

INTRODUCTION: Vaccination against mumps from 2003 is mandatory in Poland and given as two dose scheme with MMR vaccine (mumps, measles, and rubella). Earlier this vaccination was only recommended. Despite observed decline in mumps incidence for over a decade which is a result of conducted vaccinations, mumps is still a common disease among the children. AIM: To assess epidemiological situation of mumps in Poland in 2018, including vaccination coverage in Polish population, in comparison to previous years. METHODS: The descriptive analysis was based on data retrieved from routine mandatory surveillance system and published in the annual bulletins "Infectious diseases and poisonings in Poland in 2018" and "Vaccinations in Poland in 2018". RESULTS: In total, there were 1 585 mumps cases registered in Poland in 2018. Incidence of mumps was 4.1 per 100,000 and it was lower in comparison with 2017. The highest incidence (6.6 per 100 000) was registered in Opolskie voivodeship and the lowest (2.6) - in Warminsko-mazurskie voivodeship. The highest incidence rate was observed among children aged 5 years (39.2 per 100 000). Incidence in men (5.0 per 100 000) was higher than in women (3.4). In 2018, 28 people were hospitalized due to mumps. Vaccination coverage of children aged 3 years in Poland in 2018 was 92,9% and it was lower by 1.1% in comparison with year 2017. CONCLUSIONS: Systematic execution of mumps vaccination in accordance with the National Immunisation Programme resulted in a significant decrease in the number of registered cases. Due to the high vaccination coverage further decline in the number of cases is expected.

Optimal vaccine allocation during the mumps outbreak in two SIR centres.

The aim of this work is to investigate the optimal vaccine sharing between two susceptible, infected, removed (SIR) centres in the presence of migration fluxes of susceptibles and infected individuals during the mumps outbreak. Optimality of the vaccine allocation means the minimization of the total number of lost working days during the whole period of epidemic outbreak $[0,t_f]$, which can be described by the functional $Q=\int _0^{t_f}I(t)\,{\textrm{d}}t$, where $I(t)$ stands for the number of infectives at time $t$. We explain the behaviour of the optimal allocation, which depends on the model parameters and the amount of vaccine available $V$.

Outbreak of mumps in a student population with high vaccination coverage in China: time for two-dose vaccination.

In 2016, an outbreak of mumps occurred in a primary school in China with a student population having high vaccination coverage. An unmatched case-control study was performed to identify risk factors contributing to this outbreak, and a retrospective cohort study was conducted to evaluate the effectiveness of mumps-containing vaccine (MuCV). A total of 97 cases were identified during the outbreak, and the overall attack rate was 8.2%. Among students with confirmed vaccination status, 90% had received at least one dose of MuCV. Cases were more likely than non-cases to report taking the school bus during the epidemic period (adjusted OR = 2.3, 95% CI: 1.4-3.7). Vaccine effectiveness (VE) was higher for two-dose MuCV (76%, 95% CI:49â€"89%) than for one-dose MuCV (59%, 95% CI: 36â€"74%. The protection afforded by both one-dose and two-dose MuCV waned over time, from 82% among students vaccinated within 5 years to 41% among those vaccinated more than 10 years previously for one-dose VE, and from 90% to 25% over the same time period for two-dose VE. We found that outbreaks of mumps can occur in schools despite high coverage of one-dose MuCV vaccination. Although the VE of both two-dose and one-dose MuCV wanes over time, the overall VE for two-dose MuCV was superior than that of one-dose MuCV. Therefore, a two-dose MuCV schedule through routine services is likely needed in order to control mumps epidemics in China.

Humoral immunity to mumps in a highly vaccinated population in Taiwan.

BACKGROUND: A resurgence of mumps was noted recently and outbreaks were increasingly reported in populations with high vaccine coverage. We aimed to evaluate the seroprevalence to mumps in Taiwan, where a two-dose childhood mumps-containing vaccine program, with a high coverage rate, had been implemented for >20 years. METHODS: The anti-mumps IgG was determined in 3552 participants of all ages in Taiwan. The age-specific seropositivity rates were calculated and the sociodemographic variables associated with the seronegative sera were analyzed with a logistic regression method. RESULTS: The overall seroprevalence to mumps was 71%, with a higher rate in adults ≥19 years old than in the pediatric population <19 years old (80.4% versus 62.0%, P < 0.0001). In participants aged 2-20 years, who had been given at least one mumps-containing vaccine, the seropositivity fluctuated across different age subgroups and the lowest rate (36.8%) occurred in the 17-18 years age group. The multivariate analysis identified age within 17-18 years (adjusted odds ratio [aOR] 8.598, 95% confidence interval [CI] 2.990-24.722, P < 0.0001), within 19-20 years (aOR 5.076, 95% CI 1.702-15.133, P = 0.0080), and being a resident of the suburban area of northern Taiwan (aOR 1.089, 95% CI 0.823-1.414, P = 0.0008) as independent factors associated with an increased risk of seronegative sera. CONCLUSION: The seropositivity to mumps was unexpectedly low in highly vaccinated generations, and with a significant geographical discrepancy in Taiwan, which may have been responsible for the sustained reports of mumps cases in Taiwan.

Immunogenicity and Safety of an F-Genotype Attenuated Mumps Vaccine in Healthy 8- to 24-Month-Old Children.

Background: Mumps vaccine immunizations have reduced the incidence of this disease. With the variation of mumps circulating strain, novel vaccine strains are always important. Methods: A 2-center parallel, randomized, double-blind noninferiority trial was performed to compare an F-genotype attenuated mumps vaccine (SP strain) to the A-genotype vaccine (S-79, Jeryl-Lynn strain) in 1080 healthy children aged 8-24 months in Hubei, China. Results: Participants were randomly assigned to receive a high or low dose of the SP or S79 vaccine and then assessed clinically at 30 minutes and 1-28 days postinoculation. No differences in local or systemic reactivity were observed. A similar incidence of severe adverse events associated with the vaccine was observed in the high-dose group and the positive control group. Based on throat swab collections, no viral shedding was present at the 4th and 10th days in any group. Neutralizing and hemagglutination-inhibiting antibody assays with the F- or A-genotype strains showed similar trends in geometric mean titers in the high-dose SP and S79 groups. Increased cytotoxic T lymphocyte responses were observed in all groups. Conclusions: The F-genotype attenuated mumps vaccine is safe, offers immunogenicity against a homologous virus, and is noninferior to the A-genotype vaccine in 8- to 24-month-old children.

Effects of a Public Subsidy Program for Mumps Vaccine on Reducing the Disease Burden in Nagoya City, Japan.

Nagoya City initiated a public subsidy program for mumps vaccination using either the Torii or Hoshino strains in August 2010. To determine the effects of the program, we used publicly available information from Nagoya City to investigate the changes in immunization rates and numbers of patients who developed post-immunization adverse reactions, including post-vaccinal aseptic meningitis, in the 7 years since its initiation. We also investigated the numbers of mumps patients reported by sentinel sites in a national database during this period. The immunization rate in one-year-old children increased from 24.3% before the program to 91.0% after 7 years. The mean numbers of reported mumps cases per sentinel site in one-year-old to preschool children-the age groups targeted by the program- were 12.9 in the 7 years before the program and 4.93 in the 7 years after initiation of the program, showing a significant decrease of 1/2.6 (p = 0.01). The number of vaccinations during the 6.5-year period was 140,316, with only one case of aseptic meningitis reported (0.7 cases/100,000 vaccinations). No other serious adverse reactions were observed. The present findings demonstrate that the public subsidy program in Nagoya City is an effective and safe measure against mumps in children.

[Evaluation on the short term effectiveness of two doses mumps-containing vaccine policy in Shandong, China].

Objective: To evaluate the effectiveness of mumps prevention and control after implementation of two doses mumps-containing combined vaccine (MuCV) policy by analyzing epidemiological characteristics of mumps and mumps antibody levels in general population. Methods: We obtained data on cases of mumps reported during 2004-2015 from National Notifiable Diseases Reporting System (NNDRS). Descriptive analysis methods were used to describe the epidemiological characteristics of mumps during 2004-2015. MuCV immunization information from 2005 to 2015 was obtained from the immunization information management system in Shandong Province. Antibody data of mumps in healthy people were from a cross-sectional survey according to the principle of stratified random sampling from 0 to 60 years old healthy people in 2015. Commercial ELISA kits were used to detect and quantify human IgG antibodies against mumps virus in sera, and the results were analyzed statistically. Results: The average incidence of mumps from 2004 to 2015 was 11.43/100 000 in Shandong. The incidence of mumps in the central region (14.64/100 000) was higher than that in the eastern and western regions (11.14/100 000, 11.33/100 000). The incidence of mumps was still high in 2009-2013 (stage of one-dose MuCV free, 16.07/100 000) with the highest incidence of 25.33/100 000 and 24.45/100 000 occurred in 2012 and 2013 and the cases were mainly 6 to 9 years old group (172.67/100 000). Since the second dose MuCV was introduced into NIP for 6 years old children in May 2013 in Shandong, the incidence of mump decreased significantly in 2014-2015 (7.81/100 000), especially in children of 6-8 years old who were vaccinated with two doses of MuCV (2009-2013 was 114.02/100 000; 2014-2015 was 45.66/100 000) and lower than 3-5 years old vaccinated one doses of MuCV. A total of 1 785 serum samples were collected from the healthy population, the average seroprevalence was 80.62% and Geometric Mean Concentration (GMC) was 38.11 IU/ml (95%CI: 37.03-39.19 IU/ml) . There was no significant difference about seroprevalence in different regions, while the GMC in middle region was significantly higher compared to east and west region. The prevalence and GMC in children aged 19 months-2 years and 3-5 years old who received one dose of MuCV were significantly higher than those of <19 months old children. The GMC (46.88 IU/ml, 95%CI: 39.43-55.74 IU/ml) in children aged 6-9 years old who received the two doses MuCV was significantly higher than that of aged 3-5 years old children (31.71 IU/ml, 95%CI: 27.23-36.93 IU/ml). Conclusion: The incidence of mumps in Shandong was still at a high level in spite of coverage one doses MuCV to children. Compared with the period of the 1 dose MuCV immunization strategy, the incidence the groups coverage two doses MuCV was significantly reduced and lower the groups coverage one dose MuCV, but the prevalence and GMC were higher than that of the groups coverage one dose MuCV.

[Parotiditis in Chile: clinical and molecular characterization of two cases in a highly vaccinated population]. / Parotiditis en Chile: caracterización clínica y molecular de dos casos en una población altamente inmunizada.

Mumps virus usually produces a benign infection characterized by increased parotid volume which, prior to vaccination, mainly affected children and adolescents. After the introduction of measles, mumps and rubella (MMR) vaccine, mumps incidence decreased dramatically. This intervention also produced a change in its clinical presentation, moving to young adult patients, with an increased risk of complications. We report two clinical mumps cases in young adults with different clinical presentations. In both cases, serologic assays were assessed and, in one case, a polymerase chain reaction (PCR) was performed in order to confirm the diagnosis. The isolated virus was characterized and identifed as G genotype, the same genotype observed during outbreaks in United States and Europe, and different to the vaccinal strain. Mumps virus is currently circulating in Chile and it is important to be aware of possible outbreaks. Viral diagnosis can be difficult, particularly in populations with high vaccination coverage. Therefore, the access to etiologic study through PCR and serology becomes more relevant in order to optimize clinical management and secondary prevention measures.

Enhanced immunity in intradermal vaccination by novel hollow microneedles.

BACKGROUND: The intradermal (ID) route for vaccination represents an effective alternative to subcutaneous (SC)/intramuscular administration to induce protective immunity. However, a critical issue associated with ID vaccination is the precise delivery of solution in the upper dermis, which ensures enhanced immunity. METHODS: We fabricated a hollow microneedle unit made of poly-glycolic acid by injection molding and bonding, and created a dedicated prototype injector. To ensure ID delivery of solution, the injected site was macroscopically and microscopically examined. Serum immunoglobulin G antibody production was measured by enzyme immunoassay and compared in groups of rats following either ID delivery with microneedles or SC administration with a 27-G stainless needle of graded vaccine doses. RESULTS: The unit used a tandem array of six microneedles, each with a side delivery hole, and a conduit inside for solution. Microneedles installed in the injector punctured the skin with the aid of a spring. Injection of solution formed a wheal due to ID distribution. Histologically, a wedge-shaped skin defect in the upper skin corresponded to each puncture site. Antibody titers following vaccinations on days 1 and 8 were significantly higher with ID injection than with SC delivery on day 15 and every 7 days thereafter until day 36 with mumps vaccination, and until day 36 with varicella vaccination. CONCLUSIONS: The microneedle unit presented here delivered solution intradermally without any difficulty and evoked antibody responses against viruses even with the reduced vaccine volume. Our findings confirm promising results of ID delivery as an immunogenic option to enhance vaccination efficacy.

Knowledge gaps persist and hinder progress in eliminating mumps.

Mumps, a common childhood disease in the pre-vaccine era that causes swelling of the parotid salivary glands, can lead to orchitis, viral meningitis, and sensorineural deafness. While the incidence of disease decreased dramatically after the vaccine was added to standard vaccination schedules, the disease has made a substantial resurgence in recent years. As a result, it becomes critical to examine the factors involved in recurring outbreaks. Although low and incomplete vaccination coverage may be a key reason, it does not fully explain the issue due to the high rate of occurrence in populations with high vaccination coverage rates. Multiple studies suggest that waning immunity and secondary vaccine failure play a large role, the effects of which were previously masked by subclinical boosting. Significant knowledge gaps persist around the exact role and mechanism of waning immunity and demonstrate the need for more research in this area, as well as a reevaluation of mumps vaccine policy.

Mumps disease in Beijing in the era of two-dose vaccination policy, 2005-2016.

BACKGROUND: Since the introduction of mumps-containing vaccines (MuCV) in 1995 in Beijing, two-dose MuCV vaccination policy has been used, with the 1st and 2nd doses given at 18 months and 6 years of age, respectively. METHODS: Mumps epidemiology during 2005-2016 was described using surveillance data. Vaccine effectiveness (VE) of MuCV against disease was estimated for cases born during 2002-2009 and reported in 2016. VE against complications was estimated for all cases. MuCV coverage was estimated for children born during 1999-2015 using data from Beijing Immunization Information System. RESULTS: Overall mumps incidence decreased from 30.38/100,000 persons in 2005 to 10.26/100,000 persons in 2016. Incidence declines in children aged <15 years. No significant incidence change occurred in adults aged ≥20 years. Incidence in persons aged 15-19 years increased by 132.73% in 2012 when compared with in 2005. Rates of meningitis/encephalitis, orchitis, and other complications among cases decreased during 2005-2016. The majority (97%) of outbreaks occurred in schools. Total number of outbreaks and average outbreak size decreased during 2005-2016. Among outbreak-related cases, 69.54%, 29.67% and 0.79% had received 0 dose, 1dose and 2 doses of MuCV, respectively. Coverage of the 1st MuCV dose at 2-5 years of age increased by 42.75% during 2005-2016. Coverage of the 2nd MuCV dose at 6-14 years of age increased by 12.87% during 2013-2016. Overall VE estimates of MuCV against mumps disease were 74.51% (95% CI: 65.57-81.34%) for 1 dose and 83.16% (95% CI: 78.60-86.31%) for 2 doses. Both VE estimates increased by birth cohorts. VE estimate against complications for 2-dose MuCV was higher than for 1 dose. CONCLUSIONS: Increasing MuCV coverage achieved declining mumps incidence and complication rate. Current epidemiology supported 2-dose MuCV vaccination policy. The incidence rise in persons aged 15-19 years in 2012 and waning immunity for the 2nd MuCV dose merited close follow-up.

Parotiditis en Chile: caracterización clínica y molecular de dos casos en una población altamente inmunizada / Parotiditis in Chile: clinical and molecular characterization of two cases in a highly vaccinated population

Resumen El virus de la parotiditis produce una infección benigna caracterizada por un aumento de volumen parotídeo que, antes de la introducción de la vacuna tres vírica, afectaba principalmente a niños y adolescentes. Luego de que esta vacuna se implementara en el Programa Nacional de Inmunizaciones, se produjo una notable disminución en su incidencia. Además, ocasionó un cambio en la edad y presentación clínica, siendo más frecuente en adultos jóvenes con mayor riesgo de complicaciones. Presentamos dos casos clínicos de parotiditis en adultos jóvenes confirmados por serología y en uno de ellos, por biología molecular. Se caracterizó el virus como del genotipo G, como el descrito en los brotes en E.U.A y Europa, diferente al virus contenido en la vacuna. El virus parotídeo sigue circulando en nuestro país y debemos mantenernos alerta ante eventuales brotes. Se hace relevante optimizar el diagnóstico etiológico por serología o técnicas de biología molecular con fines clínicos y epidemiológicos.

Mumps virus usually produces a benign infection characterized by increased parotid volume which, prior to vaccination, mainly affected children and adolescents. After the introduction of measles, mumps and rubella (MMR) vaccine, mumps incidence decreased dramatically. This intervention also produced a change in its clinical presentation, moving to young adult patients, with an increased risk of complications. We report two clinical mumps cases in young adults with different clinical presentations. In both cases, serologic assays were assessed and, in one case, a polymerase chain reaction (PCR) was performed in order to confirm the diagnosis. The isolated virus was characterized and identifed as G genotype, the same genotype observed during outbreaks in United States and Europe, and different to the vaccinal strain. Mumps virus is currently circulating in Chile and it is important to be aware of possible outbreaks. Viral diagnosis can be difficult, particularly in populations with high vaccination coverage. Therefore, the access to etiologic study through PCR and serology becomes more relevant in order to optimize clinical management and secondary prevention measures.

Recommendation of the Advisory Committee on Immunization Practices for Use of a Third Dose of Mumps Virus-Containing Vaccine in Persons at Increased Risk for Mumps During an Outbreak.

A substantial increase in the number of mumps outbreaks and outbreak-associated cases has occurred in the United States since late 2015 (1,2). To address this public health problem, the Advisory Committee on Immunization Practices (ACIP) reviewed the available evidence and determined that a third dose of measles, mumps, rubella (MMR) vaccine is safe and effective at preventing mumps. During its October 2017 meeting, ACIP recommended a third dose of a mumps virus-containing vaccine* for persons previously vaccinated with 2 doses who are identified by public health authorities as being part of a group or population at increased risk for acquiring mumps because of an outbreak. The purpose of the recommendation is to improve protection of persons in outbreak settings against mumps disease and mumps-related complications. This recommendation supplements the existing ACIP recommendations for mumps vaccination (3).