Original Article
Recent Resurgence of Mumps in the United States
N Engl J Med 2008; 358:1580-1589April 10, 2008DOI: 10.1056/NEJMoa0706589
- Abstract
Background
The widespread use of a second dose of mumps vaccine among U.S. schoolchildren beginning in 1990 was followed by historically low reports of mumps cases. A 2010 elimination goal was established, but in 2006 the largest mumps outbreak in two decades occurred in the United States.
Methods
We examined national data on mumps cases reported during 2006, detailed case data from the most highly affected states, and vaccination-coverage data from three nationwide surveys.
Results
A total of 6584 cases of mumps were reported in 2006, with 76% occurring between March and May. There were 85 hospitalizations, but no deaths were reported; 85% of patients lived in eight contiguous midwestern states. The national incidence of mumps was 2.2 per 100,000, with the highest incidence among persons 18 to 24 years of age (an incidence 3.7 times that of all other age groups combined). In a subgroup analysis, 83% of these patients reported current college attendance. Among patients in eight highly affected states with known vaccination status, 63% overall and 84% between the ages of 18 and 24 years had received two doses of mumps vaccine. For the 12 years preceding the outbreak, national coverage of one-dose mumps vaccination among preschoolers was 89% or more nationwide and 86% or more in highly affected states. In 2006, the national two-dose coverage among adolescents was 87%, the highest in U.S. history.
Conclusions
Despite a high coverage rate with two doses of mumps-containing vaccine, a large mumps outbreak occurred, characterized by two-dose vaccine failure, particularly among midwestern college-age adults who probably received the second dose as schoolchildren. A more effective mumps vaccine or changes in vaccine policy may be needed to avert future outbreaks and achieve the elimination of mumps.
Media in This Article
Figure 1
Association between Mumps Cases and Vaccination Coverage (1968–2007) and Monthly Reports of Mumps Cases (2000–2007).Figure 2
Mumps Cases, According to County, for 2006.Article Activity
- Article
Mumps is an acute viral infection characterized by fever and inflammation of the salivary glands.1 The spectrum of illness ranges from subclinical infection to meningoencephalitis, deafness, and orchitis, and severity increases with age.2 In the prevaccine era, the highest attack rate was among children in primary school, and most adolescents showed evidence of previous infection.2
After the implementation of a policy for the administration of a one-dose mumps vaccine (Jeryl Lynn strain) for children in 1977,3 reports of mumps cases fell dramatically. However, in the late 1980s, outbreaks occurred in both unvaccinated and vaccinated adolescents and young adults.4 Widespread use of the recommended second dose of measles–mumps–rubella (MMR) vaccine for measles control among schoolchildren5 was followed by historically low rates of mumps,4 and an elimination goal for mumps was set for 2010.6
In 2006, the United States had the largest mumps epidemic in two decades. We examined the epidemiology of that outbreak to assess whether mumps elimination can be achieved through the current two-dose childhood-vaccination strategy.
Methods
Mumps Case Reports
We reviewed and classified mumps cases that were reported through the National Notifiable Diseases Surveillance System from state health departments to the Centers for Disease Control and Prevention (CDC), according to the standard clinical case definition and case classifications of the Council of State and Territorial Epidemiologists. A case that met the clinical case definition (i.e., an illness with an acute onset of unilateral or bilateral tender, self-limited swelling of the parotid or other salivary gland that lasted at least 2 days, without other apparent cause7) and that was not laboratory-confirmed was classified as a probable case. A patient with a confirmed case had a positive laboratory test or met the clinical case definition and was epidemiologically linked to a confirmed or probable case.
We defined three time periods: preresurgence (from 2000 to 2005), resurgence (2006), and postresurgence (from January 1 to June 30, 2007). Case data from the eight most severely affected states (Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, South Dakota, and Wisconsin) included vaccination status from written records and self-reported race or ethnic group; for four of the states, data were also included about patients' college attendance. Inclusion criteria for the detailed analysis were the presence of parotitis, other salivary gland inflammation, or one of seven common mumps complications (orchitis, oophoritis, mastitis, meningitis, encephalitis, deafness, and pancreatitis). Routine procedures for reporting adverse events to the Vaccine Adverse Events Reporting System after immunization were followed.
Mumps Vaccination Coverage
Due to a lack of standard methods for the national assessment of vaccine coverage from 1980 to 2006, we reviewed data regarding mumps vaccination coverage from four surveys: the U.S. Immunization Survey (USIS),8 the National Immunization Survey (NIS),9 the National Health Interview Survey (NHIS),9 and school vaccination surveys.9 Population data were derived from Census data for 2006.10
Statistical Analysis
In bivariate comparisons, we used the chi-square test and Fisher's exact test for the analysis of categorical variables and the Wilcoxon rank-sum test and analysis of Pearson's correlation for continuous variables. To evaluate the complications of mumps, we examined age, sex, race or ethnic group, and vaccination status as risk factors and included in multivariate analyses those factors with a bivariate P value of less than 0.05.
Results
Temporal Patterns
After the introduction of the mumps vaccine in 1967, reported cases dropped by 98%, from 152,209 cases in 1968 to 2982 cases in 1985 (Figure 1Figure 1
Association between Mumps Cases and Vaccination Coverage (1968–2007) and Monthly Reports of Mumps Cases (2000–2007).). Increased numbers of cases and outbreaks in the late 1980s were followed by low case counts during the period from 2000 to 2005 (the preresurgence period) when fewer than 350 cases (<30 per month) were reported annually. In contrast to recurrent spring peaks in previous years, no seasonal variation was apparent, and transmission was sporadic: only 60 of 1677 cases (4%) during the period from 2000 to 2005 were related to an outbreak.In January 2006, mumps cases were noted on college campuses in Iowa12; in February, mumps was reported on other college campuses, and by April, the outbreak had peaked, with 40 states reporting 2786 cases.13 Thereafter, reported cases steadily declined. From August to November, three outbreaks consisting of 22 to 93 cases each were reported at colleges in Illinois, Kansas, and Virginia. By December 31, a total of 6584 cases and 85 hospitalizations had been reported; no deaths occurred. No large outbreaks were reported at primary or secondary schools. During the postresurgence period (from January 1 to June 30, 2007), 359 cases (60 per month) and no outbreaks were reported.
Geographic Patterns
During the preresurgence period, the reported national incidence of mumps was less than 1 case per million persons, and cases were reported in proportion to the population of the state (r2=0.73, P<0.001) (Figure 2Figure 2
Mumps Cases, According to County, for 2006.). During the 2006 resurgence, the reported national incidence was 2.2 cases per 100,000 persons. Although mumps was reported in 45 states, the above-mentioned 8 states had the highest case counts (range, 170 to 1964) and incidence rates (2.9 to 65.9 per 100,000 persons). These states accounted for 5586 of 6584 cases (85%), although they comprised only 37.7 million of 299.4 million (13%) of the U.S. population and in the preresurgence period reported only 193 of 1677 cases (12%). Contiguously located in the Midwest, these 8 states tended to have a lower population density than did the 37 less-affected states (56.2 persons vs. 96.9 persons per square mile, P=0.08).Of 3141 U.S. counties, 879 (28%) reported mumps cases in 2006, and 47 (1%) reported having at least 25 cases, which accounted for 3548 of 6584 cases (54%). Of the 47 counties, 44 (94%) were within a 400-mile radius in the Midwest, and most of the counties were rural; the remaining 3 were in Arizona, Washington, and Virginia. The 47 counties were home to 20.9 million of the total U.S. population of 299.4 million (7%) and in the preresurgence period reported having 104 of 1677 cases (6%). Of the 47 counties, 22 (47%) had colleges that reported clusters of mumps activity. During the 2007 postresurgence period, the eight states with the highest case counts accounted for 182 of 359 cases (51%), and 47 counties accounted for 134 of 359 reports of mumps (37%). No clusters of serious adverse events after immunization campaigns were reported during the outbreak.
Laboratory and Genotyping
Mumps was confirmed by polymerase-chain-reaction (PCR) assay or viral isolation in all highly affected states. During the main outbreak period, specimens from 25 patients were genotyped at the CDC. Genotype G virus was identified in samples from 24 patients from 12 states, and genotype H virus was identified in a sample from a case imported from Bulgaria. Only a small proportion of cases could be confirmed with the use of viral isolation, PCR analysis, and classic serologic methods at the CDC.
Vaccination Coverage
One Dose among Preschoolers
During the first half of the 1980s, according to the USIS, rates of one-dose coverage for mumps-containing vaccine among 24-month-old children (as verified by vaccination cards) ranged from 78 to 80% (Figure 1). From 1995 to 2006, according to the NIS, provider-verified one-dose coverage for mumps-containing vaccine among children between the ages of 19 and 35 months was 90 to 93% nationwide and 86 to 96% in the eight highly affected states.
Two Doses among Schoolchildren
From 1997 to 2003, according to the NHIS, vaccination-card–verified two-dose coverage for mumps-containing vaccine among adolescents between the ages of 13 and 15 years rose from 68 to 77%. In 2006, according to the NIS, provider-verified two-dose coverage for mumps-containing vaccine among adolescents between the ages of 13 and 17 years was 87%. By 1992, the eight highly affected states had enacted requirements for a second dose of measles vaccine (commonly administered as MMR vaccine) for at least one cohort of schoolchildren. From the beginning of each state's requirement through the 2006–2007 school year, annual, state-specific second-dose coverage for measles-containing vaccine for kindergartners and first-graders ranged from 81 to 100% (mean, 97).
Characteristics of Patients in Eight Highly Affected States
Of the 5127 cases reported from the eight states between January 1 and July 31, 2006, 4039 (79%) met the inclusion criteria. Of these patients, age was known for 4017 (99%) (Figure 3Figure 3
Mumps Cases and Incidence, According to Age Group and Vaccination Status.). Of the 4017 patients, 1184 (29%) were between the ages of 18 and 24 years; in this age group, the incidence of mumps was higher than in all the other age groups combined by a factor of 3.7 (31.1 vs. 8.4 per 100,000, P<0.001). Data on college attendance were collected from Iowa, Kansas, Nebraska, and South Dakota. Of 768 patients between the ages of 18 and 24 years, 486 of 589 with available data (83%) reported current college attendance.The number of doses of mumps vaccine was known for 3115 of 4039 patients (77%); of the 3115 patients, 396 (13%) had received no vaccine, 772 (25%) had received one dose, and 1947 (63%) had received two or more doses. Of the patients with known vaccination status, less than 4% of those under the age of 30 years were unvaccinated; 858 of 1020 patients (84%) between the ages of 18 and 24 years had received two doses of mumps vaccine. For patients who were 30 years of age or older, the proportion who were unvaccinated rose progressively to 73%; 38% had unknown vaccination status.
The sex was known for 4012 of 4039 patients (99%), of whom 2578 (64%) were female (Figure 4AFigure 4
Mumps Cases and Incidence, According to Sex, Race or Ethnic Group, and Vaccination Status.). The incidence among female patients was higher than that among male patients by a factor of 1.8 (13.5 vs. 7.7 per 100,000, P<0.001), a finding that was not explained by differences in either vaccination status or age (proportions differed by <3% for both comparisons).Race or ethnic group was known for 3337 of 4039 patients (83%), of whom 88% were non-Hispanic white (Figure 4B). The incidence among whites was twice as high as the aggregate for all other racial or ethnic groups (9.95 vs. 4.88 per 100,000, P<0.001), a finding that was not explained by differences in either vaccination status or age (proportions differed by <4% for both comparisons).
Complications
Complications were reported for 5% of patients, and 2% of patients were hospitalized (Table 1Table 1
Clinical Manifestations and Complications. and Figure 5Figure 5
Proportion of Patients with Complications, According to Age Group and Sex.). Due primarily to orchitis, the proportion of male patients with complications was higher than that of female patients by a factor of 3.4 (P<0.001). With the exclusion of sex-specific complications, the relative proportion of complications was higher in male patients by a factor of 1.5 (P=0.16). The complication rate increased with age up to 50 years (P<0.001). Both age and sex remained significant predictors of complications when paired in a multivariate model. Neither vaccination status nor race or ethnic group was significantly associated with complications.Outbreak Response
States, in collaboration with the American College Health Association and the CDC, recommended that colleges implement a requirement that students receive two doses of MMR vaccine. The CDC and states recommended that patients with mumps be isolated for 5 to 9 days. Iowa conducted a statewide vaccination campaign for adults between the ages of 18 and 46 years, and Kansas, South Dakota, and Wisconsin conducted targeted campaigns. In June 2006, the Advisory Committee on Immunization Practices recommended the administration of two routine doses of mumps vaccine for children and health care workers and a second dose for one-dose vaccine recipients during outbreaks.14 Third doses of vaccine were not recommended.
Discussion
The largest U.S. mumps epidemic in approximately 20 years occurred in 2006, involving 6584 patients. After historically low case counts throughout the country in the early 2000s, the outbreak was unexpected, abrupt,12,13,15 and focal, primarily affecting midwestern states and colleges. However, even at the peak of the epidemic, case counts were far below those of the prevaccine era, during which tens of thousands of cases were reported monthly. The incidence was highest among college-age youths between the ages of 18 and 24 years and recipients of two doses of mumps vaccine.
Although similarities with the ongoing mumps outbreak in Canada are striking,16 the 2006 outbreak was the first account of a large-scale mumps epidemic characterized by two-dose–vaccine failure. The outbreak occurred in the context of sustained, high one-dose preschool vaccine coverage, high adolescent two-dose coverage, and implementation of a requirement for two-dose coverage for all schoolchildren in almost every state by 2007.17 Although there was no single explanation for the outbreak, multiple factors may have contributed, including waning immunity, high population density and contact rates in colleges, and incomplete vaccine-induced immunity to wild virus. Transmission from patients with subclinical and mild vaccine-modified disease may have also contributed to sustaining transmission.18
The estimated herd-immunity threshold for mumps ranges from 88 to 92%.19 Numerous outbreaks have occurred in populations with high one-dose coverage,20-22 and the effectiveness of one dose of mumps vaccine of approximately 80%1,2,20,21,23 is considered inadequate to provide population protection.24 The effectiveness of two doses of vaccine has been less extensively studied, but estimates range from 88 to 95%.23,25,26 Nevertheless, even 95% coverage with 95% vaccine effectiveness brings population immunity (90%) near the putative herd-immunity threshold. Situations of high population density and contact rates that facilitate transmission (e.g., college dormitories) may require an increased level of group-specific immunity.21,27
The 2006 outbreaks on college campuses resemble those among schoolchildren who received one dose of vaccine during the 1980s,4,20-22 which raised the issue of waning immunity after one dose of mumps vaccine. Some studies have suggested that antibody levels28,29 and vaccine effectiveness25 can wane after a second dose of mumps vaccine. Findings regarding the age group that was most affected in the 2006 outbreak (persons between the ages of 18 and 24 years) and results from two studies that were conducted on college campuses support the hypothesis of waning immunity after the second dose. One study showed that students who contracted mumps had higher odds of having received a second dose of MMR vaccine 10 or more years previously than did their roommates without mumps.18 The other study showed lower levels of mumps-neutralizing antibodies among students who had been vaccinated with a second MMR dose 15 or more years previously than among those who had been vaccinated 1 to 5 years previously.30 If population immunity is already near the herd threshold, even negligible waning immunity, particularly when combined with increased exposure, could potentiate an outbreak.
Waning immunity may be secondary to a lack of natural exposure. Persons between the ages of 18 and 24 years were born during the 1980s, when mumps activity was sufficiently low that many of them were never exposed to the disease. They probably received a second dose in the early 1990s, when opportunities for boosting from exposure to wild virus became increasingly rare. These young midwesterners entered college at a time of increased risk of the importation of mumps virus from abroad (e.g., when the 2004–2006 mumps epidemic in the United Kingdom with >70,000 patients was peaking).25,31
Besides waning immunity, other explanations are possible. The mumps virus in the U.S. outbreak was the same genotype G virus circulating during the 2004–2006 outbreak in the United Kingdom.31 Some observers have speculated that mumps vaccine–induced immunity (derived from genotype A virus) may be less effective against heterologous strains (e.g., G genotype).29,32,33 Although it is possible that antigenic differences may lead to some decrease in effectiveness, mumps vaccine was highly effective during the U.K. outbreak,25 during a small New York outbreak in 2005 that was probably caused by genotype G virus,23 and against the circulating strain in the 2006 U.S. outbreak. The U.S. outbreak was an order of magnitude lower in incidence than the U.K. outbreak, which primarily affected unvaccinated persons.31 Attack rates in the most highly affected colleges in the 2006 outbreak were less than 6%,12 considerably lower than attack rates in both the prevaccine and one-dose–vaccine eras.1 Thus, mumps vaccine probably prevented U.S. patients from numbering in the tens or hundreds of thousands.
We explored the possibility of errors in vaccine records (in which MMR vaccine was mistakenly recorded when measles vaccine was administered) as an explanation for the outbreak. However, from 1984 to 2006, 244.2 million doses of MMR vaccine were delivered, as compared with only 13.1 million doses of measles vaccine — more than enough mumps-containing vaccine to provide two doses to every cohort annually. Thus, on the basis of these data, it would be difficult to attribute the epidemic to “pseudo-vaccination.”
Male patients had a higher rate of complications than did female patients, primarily because of their risk of orchitis. As in some previous mumps outbreaks,21,34 female patients were disproportionately affected, accounting for 64% of cases. Disparities between the sexes probably reflected the sex distribution in postsecondary institutions, in which 57% of students in the eight highly affected states were women.35 Differences in behavior patterns or differential reporting patterns may also have contributed.
Mumps subsided in the summer of 2006, and sustained epidemic patterns did not return at the start of college in the fall or during the first half of 2007. Since two-dose coverage was already high and third doses were not offered, major changes in vaccine-derived immunity may not have been instrumental in stopping the outbreak or preventing its return. The resurgence may have arisen from circumstances that are unlikely to be repeated: students in rural areas with little boosting from disease entered crowded dormitories when importations were maximal. However, in the prevaccine era, mumps activity followed 3-year cycles,1 so the current low activity rate may be transient while another critical mass of susceptible persons accrues. Since 43% of the world's nations do not vaccinate against mumps,36 importations are likely to continue.
Our study had some limitations. Cases of mumps were reported through a passive surveillance system with unknown sensitivity. We consider it unlikely that differential reporting was responsible for variations in reported cases among states owing to the reporting in the national media and enhancement of surveillance nationwide. Because of low numbers of unvaccinated children and young adults, our findings that show no difference in complications according to vaccination status were driven largely by data in adults who were at least 30 years old, among whom approximately 40% had unknown vaccination status and no available written records. The resulting misclassification of vaccination status may have biased findings toward the null hypothesis. The decrease in reported rates of mumps complications, as compared with the prevaccine era,1,37 suggests that disease was modified by vaccination, although incomplete reporting of complications is an alternative explanation. We could not assess vaccine effectiveness with the use of outbreak surveillance data because of high vaccine coverage among patients with mumps.
Conventional virologic and serologic diagnostic methods (with analysis of IgM and both acute and convalescent IgG), which have been of value in confirming mumps in unvaccinated persons,23 had limited use in the highly vaccinated population in this outbreak. IgM may be transient or absent in a secondary immune response in vaccinated persons. Our experience in detecting IgM antibodies with the use of a capture assay developed by the CDC was at the lower end of the range of 15 to 50% reported in various studies in vaccinated or previously infected persons with the use of IgM antibody-capture enzyme immunoassays.38-40 The unavailability of appropriately timed specimens and the presence of low virus titers in vaccinated persons often made IgG, PCR, and isolation methods unhelpful in diagnosis. Consequently, laboratory testing was able to confirm but not rule out mumps. Future studies will help to evaluate national vaccine policy, including whether the administration of a second dose of MMR vaccine at a later age or the administration of a third dose would provide higher or more durable immunity.
Dr. Dayan, who was employed at the CDC during the preparation of this article, reports being employed at Sanofi Pasteur; Dr. O'Keefe, having an equity interest in Abbott Laboratories; and Ms. Kenyon, receiving a federal Emerging Infections and Protection grant. No other potential conflict of interest relevant to this article was reported.
The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the CDC, U.S. Department of Health and Human Services.
We thank Gregory Wallace, M.D., M.P.H., and Lisa Galloway for providing data from the National Biologics Surveillance System; Diane Simpson, M.D., Ph.D., for her kind permission to adapt USIS data regarding mumps coverage from her study of various immunization surveys; Shannon Graham, M.A., for her tireless work in producing maps of mumps activity; Larry Anderson, M.D., for his scientific leadership and guidance; and all the state, local, and CDC public health officials and the university staff members who were involved in the response to the 2006 mumps outbreak.
Source Information
From the Division of Viral Diseases (G.H.D., A.A.P., A.E.B., S.T.G., S.B.R., P.A.R., J.R., D.B., U.P., W.J.B., J.F.S.), the Immunization Services Division (S.K.S., T.A.S.), the Bacterial Diseases Division (S.W.R.), and the Influenza Division (C.B.B.), National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta; the Iowa Department of Public Health, Des Moines (M.P.Q., M.L.H.); the Kansas Department of Health and Environment, Topeka (J.M.H.S.); the Illinois Department of Public Health, Springfield (K.H., C.G.F.); the Nebraska Department of Health and Human Services, Lincoln (D.P.L., A.L.O.); the South Dakota Department of Health, Pierre (J.C., L.K.K.); the Missouri Department of Health and Senior Services, Jefferson City (E.G.D.); the Wisconsin Department of Health and Family Services, Madison (J.B.); and the Minnesota Department of Health, St. Paul (C.L.K.).
Address reprint requests to Amy Parker at MS A-47, the Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Atlanta, GA 30333.
- References
References
1
Plotkin SA. Mumps vaccine. In: Plotkin SA, Orenstein WA, eds. Vaccines. 4th ed. Philadelphia: Elsevier, 2004:441-69.
2
Galazka AM ,Robertson SE ,Kraigher A . Mumps and mumps vaccine: a global review. Bull World Health Organ 1999;77:3-14
Web of Science | Medline3
Mumps vaccine. MMWR Morb Mortal Wkly Rep 1977;26:393-394
4
van Loon FPL ,Holmes SJ ,Sirotkin BI , et al. Mumps surveillance -- United States, 1988-1993. Mor Mortal Wkly Rep CDC Surveill Summ 1995;44:1-14
Medline5
Measles prevention: recommendations of the Immunization Practices Advisory Committee (ACIP). MMWR Morb Mortal Wkly Rep 1989;38:Suppl 9:1-18
6
Department of Health and Human Services. Healthy People 2010: understanding and improving health. 2nd ed. Washington, DC: Government Printing Office, November 2000. (Accessed March 17, 2008, at http://www.healthypeople.gov/document/html/objectives/14-01.htm.)
7
Council of State and Territorial Epidemiologists. CSTE position statement 1999-ID 9. (Accessed March 17, 2008, at http://www.cste.org/ps/1999/1999-id-09.htm.)
8
Simpson DM ,Ezzati-Rice TM ,Zell ER . Forty years and four surveys: how does our measuring measure up? Am J Prev Med 2001;20:Suppl:6-14
CrossRef | Web of Science | Medline9
Centers for Disease Control and Prevention. Statistics and surveillance: immunization coverage in the U.S. (Accessed March 17, 2008, at http://www.cdc.gov/vaccines/stats-surv/imz-coverage.htm#nis.)
10
Census Bureau. Population estimates. (Accessed March 17, 2008, at http://www.census.gov/popest/datasets.html.)
11
Stokley S, McCauley M, Fishbein D, Stevenson J. Adolescent vaccination coverage levels: results from the 1997-2003 National Health Interview Survey. Presented at the 40th National Immunization Conference, Atlanta, March 6–9, 2006. (Accessed March 17, 2008, at http://cdc.confex.com/cdc/nic2006/techprogram/P10373.HTM.)
12
Mumps epidemic -- Iowa, 2006. MMWR Morb Mortal Wkly Rep 2006;55:366-368
Medline13
Update: multistate outbreak of mumps -- United States, January 1-May 2, 2006. MMWR Morb Mortal Wkly Rep 2006;55:559-563
Medline14
Updated recommendations of the Advisory Committee on Immunization Practices (ACIP) for the control and elimination of mumps. MMWR Morb Mortal Wkly Rep 2006;55:629-630
Medline15
Exposure to mumps during air travel -- United States, April 2006. MMWR Morb Mortal Wkly Rep 2006;55:401-402[Erratum, MMWR Morb Mortal Wkly Rep 2006;55:434.]
Medline16
Public Health Agency of Canada (PHAC) home page. (Accessed March 17, 2008, at http://www.phac-aspc.gc.ca/index-eng.php.)
17
Kolasa MS ,Klemperer-Johnson S ,Papania MJ . Progress toward implementation of a second-dose measles immunization requirement for all schoolchildren in the United States. J Infect Dis 2004;189:Suppl 1:S98-S103
CrossRef | Web of Science | Medline18
Cortese MM, Jordan HT, Curns AT, et al. Mumps vaccine performance among university students during a mumps outbreak. Clin Infect Dis (in press).
19
Anderson RM ,May RM . Vaccination and herd immunity to infectious diseases. Nature 1985;318:323-329
CrossRef | Web of Science | Medline20
Hersh BS ,Fine PEM ,Kent WK , et al. Mumps outbreak in a highly vaccinated population. J Pediatr 1991;119:187-193
CrossRef | Web of Science | Medline21
Cheek JE ,Baron R ,Atlas H ,Wilson DL ,Crider RD Jr . Mumps outbreak in a highly vaccinated school population: evidence for large-scale vaccination failure. Arch Pediatr Adolesc Med 1995;149:774-778
CrossRef | Web of Science | Medline22
Briss PA ,Fehrs LJ ,Parker RA , et al. Sustained transmission of mumps in a highly vaccinated population: assessment of primary vaccine failure and waning vaccine-induced immunity. J Infect Dis 1994;169:77-82
CrossRef | Web of Science | Medline23
Schaffzin JK ,Pollock L ,Schulte C , et al. Effectiveness of mumps vaccine in a summer camp outbreak. Pediatrics 2007;120:e862-e868
CrossRef | Web of Science | Medline24
Mumps virus vaccines. Wkly Epidemiol Rec 2007;82:51-60
Medline25
Cohen C ,White JM ,Savage EJ , et al. Vaccine effectiveness estimates, 2004-2005 mumps outbreak, England. Emerg Infect Dis 2007;13:12-17
Web of Science | Medline26
Harling R ,White JM ,Ramsay ME ,Macsween KF ,van den Bosch C . The effectiveness of the mumps component of the MMR vaccine: a case control study. Vaccine 2005;23:4070-4074
CrossRef | Web of Science | Medline27
Anderson RM, May RM. Infectious disease of humans: dynamics and control. New York: Oxford University Press, 1991:89-90.
28
Davidkin I ,Valle M ,Julkunen I . Persistence of anti-mumps virus antibodies after a two-dose MMR vaccination: a nine-year follow-up. Vaccine 1995;13:1617-1622
CrossRef | Web of Science | Medline29
Rubin SA, Qi L, Audet SA, et al. Antibody induced by immunization with the Jeryl Lynn mumps vaccine strain effectively neutralizes a heterologous wild-type mumps virus associated with a large outbreak. J Infect Dis (in press).
30
Date A, Kyaw M, Rue A, et al. Long-term persistence of mumps antibody after receipt of two MMR vaccinations and antibody response after a third MMR vaccination among a university population — Nebraska 2006. J Infect Dis (in press).
31
Mumps epidemic -- United Kingdom, 2004-2005. MMWR Morb Mortal Wkly Rep 2006;55:173-177
Medline32
Jin L ,Brown DWG ,Litton PA ,White JM . Genetic diversity of mumps virus in oral fluid specimens: application to mumps epidemiological study. J Infect Dis 2004;189:1001-1008
CrossRef | Web of Science | Medline33
Nojd J ,Tecle T ,Samuelsson A ,Orvell C . Mumps virus neutralizing antibodies do not protect against reinfection with a heterologous mumps virus genotype. Vaccine 2001;19:1727-1731
CrossRef | Web of Science | Medline34
Wharton M ,Cochi SL ,Hutcheson RH ,Bistowish JM ,Schaffner W . A large outbreak of mumps in the postvaccine era. J Infect Dis 1988;158:1253-1260
CrossRef | Web of Science | Medline35
Department of Education, National Center for Education Statistics. 2004 and 2005 Integrated Postsecondary Education Data System (IPEDS), Spring 2005 and Spring 2006. (Accessed March 17, 2008, at http://nces.ed.gov/programs/digest/d06/tables/dt06_196.asp.)
36
Global status of mumps immunization and surveillance. Wkly Epidemiol Rec 2005;80:418-424
Medline37
Werner CA . Mumps orchitis and testicular atrophy: occurrence. Ann Intern Med 1950;32:1066-1074
Web of Science | Medline38
Gut J-P ,Spiess C ,Schmitt S ,Kirn A . Rapid diagnosis of acute mumps infection by a direct immunoglobulin M antibody capture enzyme immunoassay with labeled antigen. J Clin Microbiol 1985;21:346-352
Web of Science | Medline39
Krause CH ,Eastick K ,Ogilvie MM . Real-time PCR for mumps diagnosis on clinical specimens -- comparison with results of conventional methods of virus detection and nested PCR. J Clin Virol 2006;37:184-189
CrossRef | Web of Science | Medline40
Sanz JC ,Mosquera Mdel M ,Echevarria JE , et al. Sensitivity and specificity of immunoglobulin G titer for the diagnosis of mumps virus in infected patients depending on vaccination status. APMIS 2006;114:788-794
CrossRef | Web of Science | Medline
- Citing Articles (74)
Citing Articles
1
M. ŠANTAK, M. LANG-BALIJA, J. IVANCIC-JELECKI, T. KOŠUTIĆ-GULIJA, S. LJUBIN-STERNAK, D. FORCIC. (2013) Antigenic differences between vaccine and circulating wild-type mumps viruses decreases neutralization capacity of vaccine-induced antibodies. Epidemiology and Infection 141:06, 1298-1309
2
Baijayantimala Mishra, Sujit Kumar Pujhari, Vandana Dhiman, P. MahaLakshmi, Abhinav Bharadwaj, Sandeep Pokhrel, Deepak Sharma, Mirnalini Sharma, Deepak Bhatia, Radha Kanta Ratho. (2013) Genotyping and subtyping of mumps virus isolates from the Indian subcontinent. Archives of Virology
3
(2013) Falldefinitionen zur Übermittlung von Erkrankungs- und Todesfällen sowie von Erregernachweisen von Mumps, Pertussis, Röteln und Varizellen. Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz
4
George E. Nelson, Annette Aguon, Engracia Valencia, Rita Oliva, Michele Leon Guerrero, Richard Reyes, Anna Lizama, Daryl Diras, Annakutty Mathew, E. Jessica Camacho, Moryne-Nicole Monforte, Tai-Ho Chen, Abdirahman Mahamud, Preeta K. Kutty, Carole Hickman, William J. Bellini, Jane F. Seward, Kathleen Gallagher, Amy Parker Fiebelkorn. (2013) Epidemiology of a Mumps Outbreak in a Highly Vaccinated Island Population and Use of a Third Dose of Measles–Mumps–Rubella Vaccine for Outbreak Control—Guam 2009 to 2010. The Pediatric Infectious Disease Journal 32:4, 374-380
5
J. ERIKSEN, I. DAVIDKIN, G. KAFATOS, N. ANDREWS, C. BARBARA, D. COHEN, A. DUKS, A. GRISKEVICIUS, K. JOHANSEN, K. BARTHA, B. KRIZ, G. MITIS, J. MOSSONG, A. NARDONE, D. O'FLANAGAN, F. DE ORY, A. PISTOL, H. THEETEN, K. PROSENC, M. SLACIKOVA, R. PEBODY. (2013) Seroepidemiology of mumps in Europe (1996–2008): why do outbreaks occur in highly vaccinated populations?. Epidemiology and Infection 141:03, 651-666
6
M. In: Ferri's Clinical Advisor 2013. Elsevier, 2013:646-728.
7
Fabio Lievano, Susan A. Galea, Michele Thornton, Richard T. Wiedmann, Susan B. Manoff, Trung N. Tran, Manisha A. Amin, Margaret M. Seminack, Kristen A. Vagie, Adrian Dana, Stanley A. Plotkin. (2012) Measles, mumps, and rubella virus vaccine (M–M–R™II): A review of 32 years of clinical and postmarketing experience. Vaccine 30:48, 6918-6926
8
Barskey , Albert E. , Schulte , Cynthia , Rosen , Jennifer B. , Handschur , Elizabeth F. , Rausch-Phung , Elizabeth , Doll , Margaret K. , Cummings , Kisha P. , Alleyne , E. Oscar , High , Patricia , Lawler , Jacqueline , Apostolou , Andria , Blog , Debra , Zimmerman , Christopher M. , Montana , Barbara , Harpaz , Rafael , Hickman , Carole J. , Rota , Paul A. , Rota , Jennifer S. , Bellini , William J. , Gallagher , Kathleen M. , . (2012) Mumps Outbreak in Orthodox Jewish Communities in the United States. New England Journal of Medicine 367:18, 1704-1713
Free Full Text9
E. Coffinières, C. Turbelin, D. Riblier, A. Aouba, D. Levy-Bruhl, C. Arena, S. Gonzalez Chiappe, J.P. Ferry, T. Hanslik, T. Blanchon. (2012) Mumps: Burden of disease in France. Vaccine 30:49, 7013-7018
10
A. Bourrillon. (2012) Oreillons. EMC - Pédiatrie - Maladies infectieuses 7:4, 1-3
11
Abdirahman Mahamud, A. Parker Fiebelkorn, George Nelson, Annette Aguon, John McKenna, Gissela Villarruel, Kathleen Gallagher, Ismael R. Ortega-Sánchez. (2012) Economic impact of the 2009–2010 Guam mumps outbreak on the public health sector and affected families. Vaccine 30:45, 6444-6448
12
E. Leuridan, N. Goeyvaerts, N. Hens, V. Hutse, P. Damme. (2012) Maternal mumps antibodies in a cohort of children up to the age of 1 year. European Journal of Pediatrics 171:8, 1167-1173
13
Kailey R. Nelson, Karen J. Marienau, Albert E. Barskey, Christopher Schembri. (2012) No evidence of mumps transmission during air travel, United States, November 1, 2006–October 31, 2010. Travel Medicine and Infectious Disease
14
Katie Greenland, Jane Whelan, Ewout Fanoy, Marjon Borgert, Koen Hulshof, Kioe-Bing Yap, Corien Swaan, Tjibbe Donker, Rob van Binnendijk, Hester de Melker, Susan Hahné. (2012) Mumps outbreak among vaccinated university students associated with a large party, the Netherlands, 2010. Vaccine 30:31, 4676-4680
15
Haytham Safi, J. Gary Wheeler, Gordon R. Reeve, Eduardo Ochoa, José R. Romero, Robert Hopkins, Kevin W. Ryan, Richard F. Jacobs. (2012) Vaccine Policy and Arkansas Childhood Immunization Exemptions. American Journal of Preventive Medicine 42:6, 602-605
16
Pascasio Peña González, José Almenara Barrios, Juan Carlos Morales Serna. (2012) Estudio de un brote epidémico de ámbito poblacional por el virus de la parotiditis G1 en JEREZ de la Frontera. Atención Primaria 44:6, 320-327
17
Jaythoon Hassan, Jonathan Dean, Eibhlín Moss, Michael J. Carr, William W. Hall, Jeff Connell. (2012) Seroepidemiology of the recent mumps virus outbreaks in Ireland. Journal of Clinical Virology 53:4, 320-324
18
Govind Prasad Sahu, Joydip Dhar. (2012) Analysis of an SVEIS epidemic model with partial temporary immunity and saturation incidence rate. Applied Mathematical Modelling 36:3, 908-923
19
Vittorio Demicheli, Alessandro Rivetti, Maria Grazia Debalini, Carlo Di Pietrantonj, Vittorio Demicheli. Vaccines for measles, mumps and rubella in children. In: Cochrane Database of Systematic Reviews. John Wiley & Sons, Ltd, 2012.
20
Young J. Juhn. (2012) Influence of Asthma Epidemiology on the Risk for Other Diseases. Allergy, Asthma & Immunology Research 4:3, 122
21
Alison Margaret Kesson. Mumps. In: Netter’s Infectious Diseases. Elsevier, 2012:47-50.
22
James F. Bale. Viral Infections of the Nervous System. In: Swaiman's Pediatric Neurology. Elsevier, 2012:1262-1290.
23
John W. Gnann. Mumps. In: Goldman's Cecil Medicine. Elsevier, 2012:2109-2111.
24
D. ONOZUKA, M. HASHIZUME. (2011) Effect of weather variability on the incidence of mumps in children: a time-series analysis. Epidemiology and Infection 139:11, 1692-1700
25
M. M. Cortese, A. E. Barskey, G. E. Tegtmeier, C. Zhang, L. Ngo, M. H. Kyaw, A. L. Baughman, J. E. Menitove, C. J. Hickman, W. J. Bellini, G. H. Dayan, G. R. Hansen, S. Rubin. (2011) Mumps Antibody Levels Among Students Before a Mumps Outbreak: In Search of a Correlate of Immunity. Journal of Infectious Diseases 204:9, 1413-1422
26
Ewout B. Fanoy, Jeroen Cremer, José A. Ferreira, Sabine Dittrich, Alies van Lier, Susan J.H. Hahné, Hein J. Boot, Robert S. van Binnendijk. (2011) Transmission of mumps virus from mumps-vaccinated individuals to close contacts. Vaccine 29:51, 9551-9556
27
Barbra M. Blair, Philip R. Fischer, Michael Libman, Lin H. Chen. Northern America. In: Infectious Diseases: A Geographic Guide. Wiley-Blackwell, 2011:309-325.
28
Hyunju Lee, Han Wool Kim, Hye Kyung Cho, Eun Ae Park, Kyong Min Choi, Kyung-Hyo Kim. (2011) Reappraisal of MMR vaccines currently used in Korea. Pediatrics International 53:3, 374-380
29
Khitam Muhsen, Tamy Shohat, Yair Aboudy, Ella Mendelson, Nurit Algor, Emilia Anis, Dani Cohen. (2011) Sero-prevalence of mumps antibodies in subpopulations subsequently affected by a large scale mumps epidemic in Israel. Vaccine 29:22, 3878-3882
30
E. ANIS, I. GROTTO, L. MOERMAN, B. WARSHAVSKY, P. E. SLATER, B. LEV. (2011) Mumps outbreak in Israel's highly vaccinated society: are two doses enough?. Epidemiology and Infection1-8
31
Benjamin M. Stermole, Greg A. Grandits, Mollie P. Roediger, Brychan M. Clark, Anuradha Ganesan, Amy C. Weintrob, Nancy F. Crum-Cianflone, Tomas M. Ferguson, Grace E. Macalino, Michael L. Landrum. (2011) Long-term safety and serologic response to measles, mumps, and rubella vaccination in HIV-1 infected adults. Vaccine 29:16, 2874-2880
32
Chee-Fu Yung, Nick Andrews, Antoaneta Bukasa, Kevin E. Brown, Mary Ramsay. (2011) Mumps Complications and Effects of Mumps Vaccination, England and Wales, 2002–2006. Emerging Infectious Diseases 17:4, 661-667
33
Hagai Levine, Omer E. Ankol, Vladi Rozhavski, Nadav Davidovitch, Yair Aboudy, Salman Zarka, Ran D. Balicer. (2011) Sub-optimal prevalence of mumps antibodies in a population based study of young adults in Israel after 20 years of two dose universal vaccination policy. Vaccine 29:15, 2785-2790
34
Sung Hee Oh. (2011) Trend in Viral Infectious Diseases in Children. Infection and Chemotherapy 43:6, 435
35
Linda A. Waggoner-Fountain. Child Care and Communicable Diseases. In: Nelson Textbook of Pediatrics. Elsevier, 2011:895.
36
Wilbert H. Mason. Mumps. In: Nelson Textbook of Pediatrics. Elsevier, 2011:1078-1081.
37
Anne A. Gershon. Chickenpox, Measles, and Mumps. In: Infectious Diseases of the Fetus and Newborn. Elsevier, 2011:661-705.
38
James E. Crowe. Prevention of Fetal and Early Life Infections Through Maternal–Neonatal Immunization. In: Infectious Diseases of the Fetus and Newborn. Elsevier, 2011:1212-1230.
39
Irja Davidkin, Mia Kontio, Mikko Paunio, Heikki Peltola. (2010) MMR vaccination and disease elimination: the Finnish experience. Expert Review of Vaccines 9:9, 1045-1053
40
David J. Weber, William A. Rutala, William Schaffner. (2010) Lessons learned: Protection of healthcare workers from infectious disease risks. Critical Care Medicine 38, S306-S314
41
Norbert G. Schwarz, Helen Bernard, Anatolie Melnic, Victoria Bucov, Natalia Caterinciuc, Matthias an der Heiden, Nick Andrews, Richard Pebody, Chinara Aidyralieva, Susan Hahné. (2010) Mumps Outbreak in the Republic of Moldova, 2007–2008. The Pediatric Infectious Disease Journal 29:8, 703-706
42
Corinne Vandermeulen, Lieven Verhoye, Sunil Vaidya, Frédéric Clement, Kevin E. Brown, Karel Hoppenbrouwers, Geert Leroux-Roels. (2010) Detection of mumps virus-specific memory B cells by transfer of peripheral blood mononuclear cells into immune-deficient mice. Immunologyno-no
43
Angela Domínguez, Núria Torner, Jesús Castilla, Joan Batalla, Pere Godoy, Marcela Guevara, Dolors Carnicer, Joan Caylà, Cristina Rius, Josep Maria Jansà. (2010) Mumps vaccine effectiveness in highly immunized populations. Vaccine 28:20, 3567-3570
44
Paul R. Lurie. (2010) Changing concepts of endocardial fibroelastosis. Cardiology in the Young 20:02, 115
45
Heinrich J. Brockhoff, Liesbeth Mollema, Gerard J.B. Sonder, Cees A. Postema, Robert S. van Binnendijk, Robert H.G. Kohl, Hester E. de Melker, Susan J.M. Hahné. (2010) Mumps outbreak in a highly vaccinated student population, The Netherlands, 2004. Vaccine 28:17, 2932-2936
46
P. M. POLGREEN, L. C. BOHNETT, M. YANG, M. A. PENTELLA, J. E. CAVANAUGH. (2010) A spatial analysis of the spread of mumps: the importance of college students and their spring-break-associated travel. Epidemiology and Infection 138:03, 434
47
Danielle M Zerr. Common Viral Infections of Childhood. Informa Healthcare, 2010:226-245.
48
Amanda L. Bonebrake, Christina Silkaitis, Gaurav Monga, Amy Galat, Jay Anderson, JoEllyn Tiesi Trad, Kenneth Hedley, Nanette Burgess, Teresa R. Zembower. (2010) Effects of Mumps Outbreak in Hospital, Chicago, Illinois, USA, 2006. Emerging Infectious Diseases 16:3, 426-432
49
Konstantin B. Blyuss, Yuliya N. Kyrychko. (2010) Stability and Bifurcations in an Epidemic Model with Varying Immunity Period. Bulletin of Mathematical Biology 72:2, 490-505
50
Seon Young Cho, Soo Young Lee, Jin Han Kang, Hui Seung Hwang. (2010) Mumps outbreak in Incheon, Korea, 2009. Korean Journal of Pediatrics 53:1, 67
51
Kyong Min Choi. (2010) Reemergence of mumps. Korean Journal of Pediatrics 53:5, 623
52
NATHAN LITMAN, STEPHEN G. BAUM. Mumps Virus. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. Elsevier, 2010:2201-2206.
53
WALTER A. ORENSTEIN, LARRY K. PICKERING, ALISON MAWLE, ALAN R. HINMAN, MELINDA WHARTON. Immunization. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. Elsevier, 2010:3917-3949.
54
Jesús Castilla, Mirian Fernández Alonso, Manuel García Cenoz, Víctor Martínez Artola, Melania Íñigo Pestaña, Isabel Rodrigo, Aurelio Barricarte. (2009) Rebrote de parotiditis en la era vacunal. Factores implicados en un brote en Navarra, 2006–2007. Medicina Clínica 133:20, 777-782
55
Albert E. Barskey, John W. Glasser, Charles W. LeBaron. (2009) Mumps resurgences in the United States: A historical perspective on unexpected elements. Vaccine 27:44, 6186-6195
56
J.S. Rota, J.C. Turner, M.K. Yost-Daljev, M. Freeman, D.M. Toney, E. Meisel, N. Williams, S.B. Sowers, L. Lowe, P.A. Rota, L.A. Nicolai, L. Peake, W.J. Bellini. (2009) Investigation of a mumps outbreak among university students with two measles-mumps-rubella (MMR) vaccinations, Virginia, September-December 2006. Journal of Medical Virology 81:10, 1819-1825
57
M. C. Baas, K. A. M. I. van Donselaar, S. Florquin, R. S. van Binnendijk, I. J. M. ten Berge, F. J. Bemelman. (2009) Mumps: Not an Innocent Bystander in Solid Organ Transplantation. American Journal of Transplantation 9:9, 2186-2189
58
Hershel Jick, Douglas P. Chamberlin, Katrina Wilcox Hagberg. (2009) The Origin and Spread of a Mumps Epidemic. Epidemiology 20:5, 656-661
59
Andrea Schreiber, Gabriel Hershman. (2009) Non-HIV Viral Infections of the Salivary Glands. Oral and Maxillofacial Surgery Clinics of North America 21:3, 331-338
60
Heidi M. Crane, Shireesha Dhanireddy, H. Nina Kim, Christian Ramers, Timothy H. Dellit, Mari M. Kitahata, Robert D. Harrington. (2009) Optimal timing of routine vaccination in HIV-infected persons. Current HIV/AIDS Reports 6:2, 93-99
61
Bell , Sigall K. Rosenberg , Eric S. . (2009) Case 11-2009. New England Journal of Medicine 360:15, 1540-1548
Full Text62
Parisa Ravanfar, Anita Satyaprakash, Rosella Creed, Natalia Mendoza. (2009) Existing antiviral vaccines. Dermatologic Therapy 22:2, 110-128
63
Jesús Castilla, Manuel García Cenoz, Maite Arriazu, Mirian Fernández-Alonso, Víctor Martínez-Artola, Jaione Etxeberria, Fátima Irisarri, Aurelio Barricarte. (2009) Effectiveness of Jeryl Lynn-containing vaccine in Spanish children. Vaccine 27:15, 2089-2093
64
Charles W. LeBaron, Bagher Forghani, Carol Beck, Cedric Brown, Daoling Bi, Cynthia Cossen, Bradley J. Sullivan. (2009) Persistence of Mumps Antibodies after 2 Doses of Measles‐Mumps‐Rubella Vaccine. The Journal of Infectious Diseases 199:4, 552-560
65
Amir Mohammad, Marcia Trape, Yosef Khan. (2009) Serological Survey of Mumps Immunity Among Healthcare Workers in Connecticut, December 2006–May 2007. Infection Control and Hospital Epidemiology 30:2, 202-203
66
Rolando Ulloa-Gutierrez, Alejandra Soriano-Fallas, Kattia Camacho-Badilla, Adriano Arguedas. (2009) 48th ICAAC/46th IDSA Annual Meeting: a pediatric perspective. Expert Review of Vaccines 8:2, 143-147
67
Kyo Hyun Kim, Chang Hwi Kim, Bo Youl Choi, Un Yeong Go, Dong Han Lee, Moran Ki. (2009) Mumps Transmission Control Status and Inapparent Infection Rate among Middle and High School Students during the 2007-2008 Mumps Outbreak in Daegu. Journal of Preventive Medicine and Public Health 42:6, 408
68
Heikki Peltola, Sari Jokinen, Mikko Paunio, Tapani Hovi, Irja Davidkin. (2008) Measles, mumps, and rubella in Finland: 25 years of a nationwide elimination programme. The Lancet Infectious Diseases 8:12, 796-803
69
Gustavo H. Dayan, Steven Rubin. (2008) Mumps Outbreaks in Vaccinated Populations: Are Available Mumps Vaccines Effective Enough to Prevent Outbreaks?. Clinical Infectious Diseases 47:11, 1458-1467
70
Karen J. Marienau, Francisco Averhoff, Susan Redd. (2008) The Role of Air Travel in the Spread of Mumps. Clinical Infectious Diseases 47:9, 1237-1237
71
Staci A. Fischer. (2008) Emerging Viruses in Transplantation: There Is More to Infection After Transplant Than CMV and EBV. Transplantation 86:10, 1327-1339
72
James D. Mancuso, Margot R. Krauss, Susette Audet, Judy A. Beeler. (2008) ELISA underestimates measles antibody seroprevalence in US military recruits. Vaccine 26:38, 4877-4878
73
(2008) Mumps in the United States. New England Journal of Medicine 359:6, 654-655
Free Full Text74
Jean Hamlin, Selvi Senthilnathan, Henry H Bernstein. (2008) Update on universal childhood immunizations. Current Opinion in Pediatrics 20:4, 483-489
- Letters
