Mumps outbreak in Orthodox Jewish communities in the United States.

BACKGROUND: By 2005, vaccination had reduced the annual incidence of mumps in the United States by more than 99%, with few outbreaks reported. However, in 2006, a large outbreak occurred among highly vaccinated populations in the United States, and similar outbreaks have been reported worldwide. The outbreak described in this report occurred among U.S. Orthodox Jewish communities during 2009 and 2010. METHODS: Cases of salivary-gland swelling and other symptoms clinically compatible with mumps were investigated, and demographic, clinical, laboratory, and vaccination data were evaluated. RESULTS: From June 28, 2009, through June 27, 2010, a total of 3502 outbreak-related cases of mumps were reported in New York City, two upstate New York counties, and one New Jersey county. Of the 1648 cases for which clinical specimens were available, 50% were laboratory-confirmed. Orthodox Jewish persons accounted for 97% of case patients. Adolescents 13 to 17 years of age (27% of all patients) and males (78% of patients in that age group) were disproportionately affected. Among case patients 13 to 17 years of age with documented vaccination status, 89% had previously received two doses of a mumps-containing vaccine, and 8% had received one dose. Transmission was focused within Jewish schools for boys, where students spend many hours daily in intense, face-to-face interaction. Orchitis was the most common complication (120 cases, 7% of male patients ≥12 years of age), with rates significantly higher among unvaccinated persons than among persons who had received two doses of vaccine. CONCLUSIONS: The epidemiologic features of this outbreak suggest that intense exposures, particularly among boys in schools, facilitated transmission and overcame vaccine-induced protection in these patients. High rates of two-dose coverage reduced the severity of the disease and the transmission to persons in settings of less intense exposure.

An evaluation of voluntary 2-dose varicella vaccination coverage in New York City public schools.

OBJECTIVES: We assessed coverage for 2-dose varicella vaccination, which is not required for school entry, among New York City public school students and examined characteristics associated with receipt of 2 doses. METHODS: We measured receipt of either at least 1 or 2 doses of varicella vaccine among students aged 4 years and older in a sample of 336 public schools (n = 223 864 students) during the 2010 to 2011 school year. Data came from merged student vaccination records from 2 administrative data systems. We conducted multivariable regression to assess associations of age, gender, race/ethnicity, and school location with 2-dose prevalence. RESULTS: Coverage with at least 1 varicella dose was 96.2% (95% confidence interval [CI] = 96.2%, 96.3%); coverage with at least 2 doses was 64.8% (95% CI = 64.6%, 64.9%). Increasing student age, non-Hispanic White race/ethnicity, and attendance at school in Staten Island were associated with lower 2-dose coverage. CONCLUSIONS: A 2-dose varicella vaccine requirement for school entry would likely improve 2-dose coverage, eliminate coverage disparities, and prevent disease.

Outbreak of measles among persons with prior evidence of immunity, New York City, 2011.

BACKGROUND: Measles was eliminated in the United States through high vaccination coverage and a public health system able to rapidly respond to measles. Measles may occur among vaccinated individuals, but secondary transmission from such individuals has not been documented. METHODS: Suspected patients and contacts exposed during a measles outbreak in New York City in 2011 were investigated. Medical histories and immunization records were obtained. Cases were confirmed by detection of measles-specific immunoglobulin M and/or RNA. Tests for measles immunoglobulin G (IgG), IgG avidity, measurement of measles neutralizing antibody titers, and genotyping were performed to characterize the cases. RESULTS: The index patient had 2 doses of measles-containing vaccine; of 88 contacts, 4 secondary patients were confirmed who had either 2 doses of measles-containing vaccine or a past positive measles IgG antibody. All patients had laboratory confirmation of measles infection, clinical symptoms consistent with measles, and high-avidity IgG antibody characteristic of a secondary immune response. Neutralizing antibody titers of secondary patients reached >80 000 mIU/mL 3-4 days after rash onset and that of the index was <500 mIU/mL 9 days after rash onset. No additional cases of measles occurred among 231 contacts of secondary patients. CONCLUSIONS: This is the first report of measles transmission from a twice-vaccinated individual with documented secondary vaccine failure. The clinical presentation and laboratory data of the index patient were typical of measles in a naive individual. Secondary patients had robust anamnestic antibody responses. No tertiary cases occurred despite numerous contacts. This outbreak underscores the need for thorough epidemiologic and laboratory investigation of suspected cases of measles regardless of vaccination status.

Serologically confirmed household transmission of 2009 pandemic influenza A (H1N1) virus during the first pandemic wave--New York City, April-May 2009.

BACKGROUND: Understanding transmissibility of influenza viruses within households is critical for guiding public health response to pandemics. We studied serologically confirmed infection and disease among household contacts of index case patients with 2009 pandemic influenza A (H1N1) virus (pH1N1) infection in a setting of minimal community pH1N1 transmission. METHODS: We defined index case patients as students and staff of a New York City high school with laboratory-confirmed pH1N1 infection during the earliest phase of the pH1N1 outbreak in April 2009. We visited households of index case patients twice, once in early May and again in June/July 2009. At each visit, household members (both index case patents and household contacts) provided serum samples and completed questionnaires about illness and possible risk factors. Serologic testing was performed using microneutralization and hemagglutination-inhibition assays. RESULTS: Of 79 eligible household contacts in 28 households, 19% had serologically confirmed pH1N1 infection, and 28% of those infected were asymptomatic. Serologically confirmed infection varied by age among household contacts: 36% of contacts younger than 10 years were infected, compared with 46% of contacts age 10-18 years, 8% of contacts aged 19-54 years, and 22% of contacts aged 55 years and older. CONCLUSIONS: Infection rates were high for household contacts of persons with confirmed pH1N1, particularly for contacts aged 10-18 years, and asymptomatic infection was common. Efforts to reduce household transmission during influenza pandemics are important adjuncts to strategies to reduce community illness.

Use of Capture-Recapture Analysis to Assess Reporting Completeness of Births to Hepatitis B-Positive Women in New York City, 2013-2014.

OBJECTIVES: The New York City (NYC) Department of Health and Mental Hygiene (DOHMH) depends on reporting by health care facilities and laboratories for disease surveillance. Our objective was to evaluate the completeness of DOHMH surveillance to identify births to hepatitis B virus (HBV)-positive women to prevent perinatal transmission. METHODS: We identified infants born to HBV-positive women by matching mothers of all infants born in NYC during May 1, 2013-May 1, 2014, identified from the Citywide Immunization Registry (CIR) to persons with HBV-positive laboratory reports in the Electronic Laboratory Reporting (ELR) system. We then matched infants born to mothers identified in the CIR/ELR match to infants born to HBV-positive women from the DOHMH perinatal HBV surveillance database. We performed capture-recapture analysis to evaluate completeness of DOHMH case identification. We compared the proportion of infants born to HBV-positive mothers reported to DOHMH with the proportion of infants identified only through the CIR/ELR match for receipt of postexposure prophylaxis (PEP) and completion of the HBV vaccination series and post-vaccination serology testing. RESULTS: Of 1662 infants identified from the CIR/ELR match and 1554 infants in the DOHMH database, 1493 infants matched. Of 169 infants only in the CIR/ELR data set, 55 were born to HBV-positive women residing in NYC. Sixty-one infants were only in the DOHMH database. An estimated 2 infants were not identified by either method. The CIR/ELR match increased infant identification by 3.5%, from 1554 to 1609 infants. The proportion of infants who received PEP was significantly higher among infants whose mothers were reported to DOHMH (vs not reported to DOHMH). PRACTICAL IMPLICATIONS: Use of the CIR/ELR match may further improve DOHMH identification of infants born to HBV-positive women and receipt of infant PEP.

Invasive Pneumococcal Disease Following the Introduction of 13-Valent Conjugate Vaccine in Children in New York City From 2007 to 2012.

IMPORTANCE: Invasive pneumococcal disease (IPD) is a leading cause of pneumonia, meningitis, and bacteremia in children. In March 2010, a 13-valent pneumococcal conjugate vaccine (PCV13) was introduced to the routine childhood immunization schedule. The PCV13 contains 6 serotypes not included in the previously recommended 7-valent pneumococcal conjugate vaccine, including serotype 19A, the predominant cause of IPD prior to the introduction of PCV13. OBJECTIVES: To describe changes in the epidemiology and incidence of IPD in children younger than 5 years in New York City (NYC) after the introduction of PCV13 and assess PCV13 coverage in NYC. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of population-based IPD surveillance data of the general population residing in NYC between January 1, 2007, and December 31, 2012. Invasive pneumococcal disease cases were identified by laboratory reporting of positive pneumococcal cultures from a normally sterile body site in NYC residents younger than 5 years. Isolates were serotyped. Participants included 468 cases younger than 5 years with IPD reported through routine surveillance to the NYC Department of Health and Mental Hygiene. MAIN OUTCOMES AND MEASURES: Absolute differences and percentage changes in IPD incidence before and after the introduction of PCV13 by serotype grouping, age, and race/ethnicity. The number of PCV13 doses administered to children younger than 5 years was calculated using the NYC immunization information system. RESULTS: There were 468 IPD cases from 2007 to 2012. The incidence of IPD decreased by 69.6% (95% CI, -79.3% to -55.5%) from 21.0 cases per 100 000 (2007-2009 mean) pre-PCV13 to 6.4 cases per 100 000 (2011-2012 mean) post-PCV13. Estimates of disease caused by serotypes included in the PCV13 decreased by 82.5% (95% CI, -90.0% to -69.3%), including a 79.7% reduction in serotype 19A (95% CI, -89.0% to -62.4%). Reductions in IPD incidence were seen in all age groups, with the largest reduction in children younger than 12 months (80.4%; P = .005). Incidence decreased significantly in all racial/ethnic groups. The percentage of children younger than 5 years in NYC with 1 or more doses of PCV13 increased from 47.8% in 2010 to 89.8% in 2012. CONCLUSIONS AND RELEVANCE: The incidence of IPD in NYC children younger than 5 years and, particularly, the incidence of IPD caused by serotype 19A decreased dramatically following the introduction of PCV13, with reductions among all age and racial/ethnic groups. This represents a significant achievement for public health immunization programs and underscores the importance of achieving high immunization coverage.

Mumps vaccine effectiveness and risk factors for disease in households during an outbreak in New York City.

BACKGROUND AND OBJECTIVES: Mumps outbreaks have been reported among vaccinated populations, and declining mumps vaccine effectiveness (VE) has been suggested as one possible cause. During a large mumps outbreak in New York City, we assessed: (1) VE of measles-mumps-rubella vaccine (MMR) against mumps and (2) risk factors for acquiring mumps in households. METHODS: Cases of mumps were investigated using standard methods. Additional information on disease and vaccination status of household contacts was collected. Case households completed follow-up phone interviews 78-198 days after initial investigation to ascertain additional cases. Mumps cases meeting the study case definition were included in the analysis. Risk factors for mumps were assessed, and VE was calculated using secondary household attack rates. RESULTS: Three hundred and eleven households with 2176 residents were included in the analysis. The median age of residents was 13 years (range <1-85), and 462 (21.2%) residents met the study mumps case definition. Among 7-17 year olds, 89.7% received one or more doses of MMR vaccine, with 76.7% receiving two doses. Young adults aged 10-14 years (OR=2.4, CI=1.3-4.7) and 15-19 years (OR=2.5, CI=1.3-5.0) were at highest risk of mumps. The overall 2-dose VE for secondary contacts aged five and older was 86.3% (CI 63.3-94.9). CONCLUSIONS: The two-dose effectiveness of MMR vaccine against mumps was 86.3%, consistent with other published mumps VE estimates. Many factors likely contributed to this outbreak. Suboptimal MMR coverage in the affected population combined with VE may not have conferred adequate immunity to prevent transmission and may have contributed to this outbreak. Achieving high MMR coverage remains the best available strategy for prevention of mumps outbreaks.

Environmental factors potentially associated with mumps transmission in yeshivas during a mumps outbreak among highly vaccinated students: Brooklyn, New York, 2009-2010.

During 2009-2010, a large US mumps outbreak occurred affecting two-dose vaccinated 9th-12th grade Orthodox Jewish boys attending all-male yeshivas (private, traditional Jewish schools). Our objective was to understand mumps transmission dynamics in this well-vaccinated population. We surveyed 9th-12th grade male yeshivas in Brooklyn, NY with reported mumps case-students between 9/1/2009 and 3/30/2010. We assessed vaccination coverage, yeshiva environmental factors (duration of school day, density, mixing, duration of contact), and whether environmental factors were associated with increased mumps attack rates. Ten yeshivas comprising 1769 9th-12th grade students and 264 self-reported mumps cases were included. The average yeshiva attack rate was 14.5% (median: 13.5%, range: 1-31%), despite two-dose measles-mumps-rubella vaccine coverage between 90-100%. School duration was 9-15.5 h/day; students averaged 7 h face-to-face/day with 1-4 study partners. Average daily mean density was 6.6 students per 100 square feet. The number of hours spent face-to-face with a study partner and the number of partners per day showed significant positive associations (p < 0.05) with classroom mumps attack rates in univariate analysis, but these associations did not persist in multivariate analysis. This outbreak was characterized by environmental factors unique to the yeshiva setting (e.g., densely populated environment, prolonged face-to-face contact, mixing among infected students). However, these features were present in all included yeshivas, limiting our ability to discriminate differences. Nonetheless, mumps transmission requires close contact, and these environmental factors may have overwhelmed vaccine-mediated protection increasing the likelihood of vaccine failure among yeshiva students.

Comparison of the sensitivity of laboratory diagnostic methods from a well-characterized outbreak of mumps in New York city in 2009.

A mumps outbreak in upstate New York in 2009 at a summer camp for Orthodox Jewish boys spread into Orthodox Jewish communities in the Northeast, including New York City. The availability of epidemiologic information, including vaccination records and parotitis onset dates, allowed an enhanced analysis of laboratory methods for mumps testing. Serum and buccal swab samples were collected from 296 confirmed cases with onsets from September through December 2009. All samples were tested using the Centers for Disease Control and Prevention (CDC) capture IgM enzyme immunoassay (EIA) and a real-time reverse transcription-PCR (rRT-PCR) that targets the short hydrophobic gene. A subset of the samples (n = 205) was used to evaluate 3 commercial mumps IgM assays and to assess the sensitivity of using an alternative target gene (nucleoprotein) in the rRT-PCR protocol. Among 115 cases of mumps with 2 documented doses of measles, mumps, and rubella (MMR) vaccine, the CDC capture IgM EIA detected IgM in 51% of serum samples compared to 9% to 24% using three commercial IgM assays. The rRT-PCR that targeted the nucleoprotein gene increased RNA detection by 14% compared to that obtained with the original protocol. The ability to detect IgM improved when serum was collected 3 days or more after symptom onset, whereas sensitivity of RNA detection by rRT-PCR declined when buccal swabs were collected later than 2 days after onset. Selection of testing methods and timing of sample collection are important factors in the ability to confirm infection among vaccinated persons. These results reinforce the need to use virus detection assays in addition to serologic tests.

Intussusception after administration of the rhesus tetravalent rotavirus vaccine (Rotashield): the search for a pathogenic mechanism.

OBJECTIVES: The rhesus tetravalent rotavirus vaccine (RRV) was withdrawn from the routine program for childhood immunization in the United States because of the rare and unexpected occurrence of intussusception in the 2-week period after administration of the first dose. METHODS: To search for the pathogenesis of this association, we compared the pathology of surgical specimens from infants who had surgical reduction of their intussusceptions within 2 weeks of receiving the vaccine (case patients; n = 8) with the pathology of specimens from children who had surgery > 2 weeks after immunization (n = 6) or who had never been immunized (n = 26). Tissue was examined for evidence of the vaccine strain of rotavirus by reverse transcriptase-polymerase chain reaction (RT-PCR), in situ hybridization, and immunohistochemical staining. RESULTS: RRV was identified by RT-PCR in tissue samples from 7 of the 8 case patients and in 2 of the 6 children who received the vaccine at a more distant time (29 and 58 days before surgery), but it was not identified in samples from any of the nonvaccinated children. No evidence of rotavirus tissue involvement was detected in any of the children by in situ hybridization or immunohistochemical staining. Pathologic evidence (for example, inclusion bodies, smudge cells) of adenovirus infection was present in 35% of the 37 specimens examined by routine staining and immunohistochemistry. CONCLUSIONS: The fact that RRV was detected by RT-PCR but not by either of the other assays could be explained by RRV being present in the lumen of the gut but not in the tissues of appendix, ileum, or Peyer's patches. The Peyer's patches were not hyperplastic, and we could not establish the pathogenic mechanism for this association.