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Context: Childhood vaccination has reduced rubella disease to low levels in the United States, but outbreaks continue to occur. The largest outbreak in the past 5 years occurred in Nebraska in 1999.Objectives: To examine risk factors for disease, susceptibility of the risk population, role of vaccine failure, and the need for new vaccination strategies in response to the Nebraska rubella outbreak.Design, Setting, and Patients: Investigation of 83 confirmed rubella cases occurring in Douglas County, Nebraska, between March 23 and August 24, 1999; serosurvey of 413 pregnant women in the outbreak locale between October 1998 and March 1999 (prior to outbreak) and April and November 1999 (during and after outbreak).Main Outcome Measures: Case characteristics, compared with that of the general county population; area childhood rubella vaccination rates; and susceptibility among pregnant women before vs during and after the outbreak.Results: All 83 rubella cases were unvaccinated or had unknown vaccination status and fell into 3 groups: (1) 52 (63%) were young adults (median age, 26 years), 83% of whom were born in Latin American countries where rubella vaccination was not routine. They were either employed in meatpacking plants or were their household contacts. Attack rates in the plants were high (14.4 per 1000 vs 0. 19 per 1000 for general county population); (2) 16 (19%), including 14 children (9 of whom were aged <12 months) and 2 parents, were US-born and non-Hispanic, who acquired the disease through contacts at 2 day care facilities (attack rate, 88.1 per 1000); and (3) 15 (18%) were young adults (median age, 22 years) whose major disease risk was residence in population-dense census tracts where meatpacking-related cases resided (R(2) = 0.343; P<.001); 87% of these persons were born in Latin America. Among pregnant women, susceptibility rates were 13% before the outbreak and 11% during and after the outbreak. Six (25%) of 24 susceptible women tested were seropositive for rubella IgM. Rubella vaccination rates were 90.2% for preschool children and 99.8% for school-aged children.Conclusions: A large rubella outbreak occurred among unvaccinated persons in a community with high immunity levels. Crowded working and living conditions facilitated transmission, but vaccine failure did not. Workplace vaccination could be considered to prevent similar outbreaks. JAMA. 2000;284:2733-2739. [ABSTRACT FROM AUTHOR]

Objective: To assess the impact of different interventions to increase measles vaccination coverage among preschool children enrolled in the Special Supplemental Food Program for Women, Infants, and Children (WIC).Design: Public health intervention trial.Setting: Six volunteer WIC sites in New York City.Study Participants: Children aged 12 to 59 months presenting for WIC certification between April 1 and September 30, 1991, who were eligible for measles vaccination.Interventions: Two WIC sites were assigned at random to one of three immunization strategies: (1) escort: child was escorted to a nearby pediatric clinic for immunization; (2) voucher incentive: the family returned monthly, rather than every 2 months, to pick up WIC food vouchers until the child was immunized; or (3) referral: the family was passively referred for immunization.Main Outcome Measure: Proportion of eligible children receiving measles vaccination.Results: Of children eligible for measles immunization, 74% (618/836) were immunized. Children at escort sites were 5.5 times (relative risk [RR] = 5.5; 95% confidence interval [CI], 3.7 to 8.1) and those at voucher incentive sites were 2.9 times (RR = 2.9; 95% CI, 1.9 to 4.5) more likely to be immunized than children at referral sites. Children were immunized more rapidly at escort sites (median, 14 days) and voucher incentive sites (median, 26 days) than at referral sites (median, 45 days; P < .001).Conclusions: Both escort and voucher incentive models resulted in more children being immunized more rapidly than passive referral. Because of ease of administration, voucher incentives may be a more suitable immunization intervention for use at WIC sites, with addition of escort where feasible. [ABSTRACT FROM AUTHOR]

Context: Inner-city immunization rates have lagged behind those in other areas of the country.Objective: To evaluate the impact of an initiative linking immunization with distribution of food vouchers in the inner city.Design: Retrospective analysis of immunization data gathered in 1996 and 1997.Setting: Nineteen Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) sites serving 30% of the Chicago, III, birth cohort.Participants: A total of 16581 children 24 months old or younger.Interventions: Voucher incentives (varying frequency of food voucher issuance based on immunization status) and assessment of immunization status and referral to immunization provider.Main Outcome Measures: Age-appropriate immunization rates and WIC enrollment rates.Results: During the 15-month period of evaluation, immunization rates increased from 56% to 89% at sites performing voucher incentives. The proportion of children needing voucher incentives declined from 51% to 12%. Sites performing assessment and referral, but not providing voucher incentives, showed no evidence of improvement in immunization coverage. No difference was observed in enrollment rates between sites performing voucher incentives and those that did not.Conclusion: Applied in a large-scale, programmatic fashion, voucher incentives in WIC can rapidly increase and sustain high childhood immunization rates in an inner-city population. [ABSTRACT FROM AUTHOR]

The article focuses on a report on the 2009 monovalent influenza A (H1N1) vaccination in the U.S., published in the 2010 issue of the "Morbidity and Mortality Weekly Report." The Advisory Committee on Immunization Practices (ACIP) recommended the inclusion of health care personnel (HCP) as one of the five target groups to receive the influenza A monovalent vaccine. The report summarized the results of an online population-based panel survey designed to assess vaccination coverage, conducted in January 2010. It revealed that the estimated vaccination coverage for 2009 pandemic influenza A (H1N1) was 37. 1 percent, and 61.9 percent for seasonal influenza. The views of the U.S. Centers for Disease Control and Prevention (CDC) on influenza A (H1N1) vaccination are also highlighted. INSET: What is already known on this topic?.

Background: Intussusception is a form of intestinal obstruction in which a segment of the bowel prolapses into a more distal segment. Our investigation began on May 27, 1999, after nine cases of infants who had intussusception after receiving the tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV) were reported to the Vaccine Adverse Event Reporting System., Methods: In 19 states, we assessed the potential association between RRV-TV and intussusception among infants at least 1 but less than 12 months old. Infants hospitalized between November 1, 1998, and June 30, 1999, were identified by systematic reviews of medical and radiologic records. Each infant with intussusception was matched according to age with four healthy control infants who had been born at the same hospital as the infant with intussusception. Information on vaccinations was verified by the provider., Results: Data were analyzed for 429 infants with intussusception and 1763 matched controls in a case-control analysis as well as for 432 infants with intussusception in a case-series analysis. Seventy-four of the 429 infants with intussusception (17.2 percent) and 226 of the 1763 controls (12.8 percent) had received RRV-TV (P=0.02). An increased risk of intussusception 3 to 14 days after the first dose of RRV-TV was found in the case-control analysis (adjusted odds ratio, 21.7; 95 percent confidence interval, 9.6 to 48.9). In the case-series analysis, the incidence-rate ratio was 29.4 (95 percent confidence interval, 16.1 to 53.6) for days 3 through 14 after a first dose. There was also an increase in the risk of intussusception after the second dose of the vaccine, but it was smaller than the increase in risk after the first dose. Assuming full implementation of a national program of vaccination with RRV-TV, we estimated that 1 case of intussusception attributable to the vaccine would occur for every 4670 to 9474 infants vaccinated., Conclusions: The strong association between vaccination with RRV-TV and intussusception among otherwise healthy infants supports the existence of a causal relation. Rotavirus vaccines with an improved safety profile are urgently needed.

Background: A large body of scientific and programmatic data has demonstrated that provider measurement and feedback raises immunization coverage. Starting in 1995, Congress required that all states measure childhood immunization coverage in all public clinics, and federal grant guidelines encourage private practice measurements., Objectives: To determine state immunization measurement rates and examine risk factors for high rates., Methods: Review of 1997 state reports, with correlation of measurement rates to birth cohort and provider numbers, public/private proportions, and vaccine distribution systems., Results: Of the 9505 public clinics, 48% were measured; 4 states measured all clinics; 29 measured a majority. Measurement rates were highest for Health Department clinics (67%), lower for community/migrant health centers (39%), and lowest for other clinics (22%). Rates were highly correlated among categories of clinics (r>+0.308, P<.03), and the fewer the clinics, the higher the measurement rates (r = -0.351, P =. 01), but other factors were not significant. Of the 41,378 private practices, 6% were measured; no state measured all its practices; 1 measured a majority. Private practice measurement rates were not correlated to public clinic measurement rates or other factors examined. Of the 50,883 total providers, 14% were measured; no state measured all providers; 2 measured a majority. A trend toward higher measurement rates was found in states with fewer providers (r = -0. 266, P =.06)., Conclusions: Three years after the congressional mandate, only a minority of public clinics and very few private practices had their immunization coverage measured. Greater efforts will be needed to assure implementation of the intervention. Arch Pediatr Adolesc Med. 2000;154:832-836

Context: Because well-child care represents the most important prevention opportunity in the health care system, a growing number of activities and indicators have been proposed for it., Objective: To measure the time spent in the various components of well-child care., Design: Time-and-motion study., Setting: Five private pediatric practices and 2 public providers in Rochester, NY., Participants: One hundred sixty-four children younger than 2 years., Main Outcome Measure: Duration of family's encounters with the primary care provider (physician or nurse practitioner), nurse, and other personnel., Results: The median encounter times and their component parts in minutes were: (1) primary care provider, 16.3 (physical examination, 4.9; vaccination discussion, 1.9; discussion of other health issues, 9.5; vaccination administration, 0); (2) nurse, 5.6 (physical examination, 3.5; vaccination discussion, 0; other health discussion, 0; vaccine administration, 1.6); and (3) other personnel, 0 for all categories. Public provider setting, African American race of the child, and administration of 4 vaccinations were significantly associated with an increase (3-4 minutes) in the duration of the primary care provider encounter. Only 8 (5%) of families read vaccine information materials., Conclusions: Depending on whether a child makes the usual 3 or recommended 6 number of well-child visits, the total time of well-child care is 45 to 90 minutes during the first year of life and declines to less than 30 minutes per year thereafter as the number of recommended visits diminish. Because high-risk children make half as many well-child care visits as other children, a 3 to 4 minute increase in encounter time is insufficient to provide them with the same level of care as other children.

Inner-city infants (n = 565) enrolled in the WIC program were randomly assigned at 6 months of age to either of 2 groups: (1) voucher incentive (frequency of issuance of food vouchers based on immunization status) plus reminder-recall (calls and/or letters to families of under-vaccinated children) or (2) voucher incentive alone. At 12 months, both groups' immunization levels were high and not significantly different: 80% +/- 4% versus 79% +/- 5% (P =.749).

Background: Since 1995, states and jurisdictions receiving federal immunization funds have been required to perform annual measurements of vaccination coverage in their public clinics, based on data from Georgia where clinic coverage increased after the institution of a measurement and feedback intervention., Objective: To determine if clinic vaccination coverage improved in localities that used the Georgia intervention model., Design: Retrospective examination of clinic vaccination coverage data., Participants: Children aged 19 to 35 months enrolled in clinics in localities that had applied the intervention for 4 years or longer., Intervention: The Georgia intervention model: assessment of clinic vaccination coverage, feedback of the information to the clinic, incentives to clinics, and promotion of exchange of information among clinics (AFIX)., Main Outcome Measure: Change in median clinic coverage rates, based on the primary (4-3-1) vaccine series, with comparison to results of the National Immunization Survey., Results: Four states and 2 cities that had applied the AFIX intervention for 4 years or longer were identified. The number of clinic records reviewed annually was 4639 to 18000 in 73 to 116 clinics for states, and 714 to 5276 in 8 to 25 clinics for cities. Median clinic coverage rose in all localities: Missouri, 44% (1992) to 93% (1997); Louisiana, 61% (1992) to 83% (1997); Colorado, 55% (1993) to 75% (1997); Iowa, 71% (1994) to 89% (1997); Boston, Mass, 41% (1994) to 79% (1997); and Houston, Tex, 28% (1994) to 84% (1997). The increase in clinic coverage exceeded that of the general population in 5 localities and was identical in the sixth. The average annual coverage rise attributable to the intervention was +5 percentage points per year (Georgia, +6 per year). The average crude direct program cost was $49533 per locality per year., Conclusion: The Georgia intervention model (AFIX) can be reproduced elsewhere and is associated with improvements in clinic vaccination coverage.

Objective: To evaluate the impact of interventions by a community-based organization on immunization rates., Design: Controlled community intervention trial., Setting and Participants: Children aged 3 to 59 months in Fulton County, Georgia, who were patients of 1 of 4 public clinics (clinic based), or residents of 1 of 9 inner-city communities (residence based)., Interventions: (1) Clinic-based intervention included monthly review of clinic vaccination records to identify undervaccinated children followed by contact with family (reminder-recall strategy); (2) residence-based intervention included door-to-door assessment and education campaigns followed by mobile van vaccinations, temporary on-site vaccination stations, free child care and transportation to providers, incentives of food and baby products, focus groups, and coalitions with local organizations (community saturation with vaccination messages and opportunities)., Outcome Measures: Change in vaccination rates after 1 year based on clinic record reviews and population surveys., Results: For clinic-based intervention, series completion rates improved from 43% (87/204) to 58% (99/170) in intervention clinics (P=.003), while rates in control clinics did not change from the baseline of 52% (81/157 to 78/150), for a net difference between intervention and control arms of +15 percentage points (P=.046). For residence-based intervention, age-appropriate vaccination rates improved from 44% (154/347) to 61% (260/429) in intervention communities (+17 percentage points; P<.001) compared with improvement of 44% (78/178) to 58% (129/221) for control communities (+14 percentage points; P=.004), but the difference between arms was not significant (+3 percentage points, P=.78)., Conclusions: Reminder-recall activities by the community-based organization improved vaccination rates in intervention clinics compared with control clinics. A statistically significant impact on vaccination rates could not be detected for residence-based interventions by the community-based organization.

All states are now required by federal law to measure immunization coverage in each public clinic in their jurisdiction once a year. This law is based on data suggesting a twofold increase of immunization coverage in public clinics in Georgia during a seven-year period when the state developed a system for measuring clinic coverage and using these data to stimulate immunization performance. Review of the history of the development of the Georgia system suggests that measurement alone is not sufficient to raise coverage, however. In Georgia, measurement was coupled with a vigorous program of feedback of coverage data, provision of incentives for good performance, and exchange of information among clinics. The Centers for Disease Control and Prevention (CDC) has summarized the Georgia system with the acronym AFIX--Assessment, Feedback, Incentives, eXchange of information--and recommends that all state immunization program managers test and adapt this methodology. The article comments on the development of the Georgia system and describes why CDC believes other states should adopt it.

In temperate regions rotavirus diarrhea is a disease of the cooler months of the year, but little is known about its patterns in the summer. We report on the first year of national surveillance of rotavirus, during which we actively investigated patterns of summer activity. We obtained data on rotavirus testing from 85 laboratories in 48 states, conducted a survey of their testing practices and retested for confirmation positive specimens from laboratories reporting high rates of positivity during the summer. During 1989 participating laboratories reported 4011 specimens tested for rotavirus during July and August, of which 436 (11%) were said to be positive. Most laboratories reported low rates of positivity during these months (median percent positive, 3), but five had very high rates of summer positivity (> 30%). These five laboratories were geographically separated, and neighboring laboratories showed little rotavirus activity. Positive specimens submitted by four of these centers with high rates of summer rotavirus could not be confirmed. A survey of laboratory methods found one commercial assay (TestPack) and two laboratory practices (failure to use controls and involvement of more than six technicians in the testing process) to be associated with high rates of summer positivity. Moderate rates of positivity (11 to 30%) were fond frequently in the southwest during July and August; reference testing of specimens from these laboratories confirmed positivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Geographic and temporal trends of rotavirus detections in the United States for the period January 1989-May 1991 were determined by analyzing data reported monthly by 47 virology laboratories participating in the North American Rotavirus Surveillance System. Reports included complete information on the number of specimens tested, the number of test results positive for rotavirus, and the method used to detect rotavirus. Consistent trends in regional and geographic area were identified, with distinctly different peaks of rotavirus activity in the western and eastern states. Each year in the western states, rotavirus activity began in November and peaked in December-January, whereas in the eastern states activity began in January and peaked in February-March. These differences do not correlate with obvious trends in strain variation of rotavirus and remain unexplained. Unexpected reporting of summer rotavirus activity by some laboratories in 1989 was traced to the use of a single diagnostic kit and to two questionable laboratory practices: having more than six medical technologists perform the test and failure to use controls with the test. Laboratory-based surveillance of rotavirus activity has proven to be useful in identifying and correcting problems in laboratory methods for detecting rotavirus and will be a sensitive means for monitoring coverage of the rotavirus vaccine now being developed.

Although the importance of diarrhea as a prime cause of morbidity and death in developing countries is well recognized, the disease burden in the United States has never been thoroughly examined. We have prepared national estimates of the annual number of cases of diarrhea in children less than 5 years of age and of the outcome, measured in terms of visits to a physician, hospitalizations, and deaths. The annual number of diarrheal episodes was estimated by reviewing longitudinal studies of childhood diarrhea conducted in the United States and extrapolating these data to the nation. Estimates of physician visits, hospitalizations, and deaths were prepared from a variety of national data sources. We estimate that 16.5 million children less than 5 years of age have between 21 and 37 million episodes of diarrhea annually. Of these, 2.1 to 3.7 million episodes lead to a physician visit, a total of 220,000 patients are hospitalized, and 325 to 425 children die. The major cost of diarrhea lies in the high numbers and cost of hospitalizations, because approximately 10.6% of hospitalizations in this age group are for diarrhea. Diarrheal deaths occur in relatively small numbers, are more common in the South and among black persons, are potentially avoidable, and could represent as much as 10% of the preventable postneonatal infant death in the United States. These estimates underscore the extensive burden of diarrheal illness in children in the United States and suggest that interventions to prevent disease or decrease its severity could be cost-effective.

Recent discoveries have implicated a number of "new" (i.e., previously unrecognized) infectious agents as important causes of outbreaks of gastroenteritis. Unfortunately, the ability to detect these agents in an outbreak can be limited by two factors: 1) the lack of appropriate assays-many of which are still in developmental stages and are not readily available to clinical laboratories, and 2) inadequately or improperly collected specimens. At CDC, many newly developed assays are being used for research and for outbreak investigations. The information in this report is especially intended for public health agencies that collaborate with CDC in investigating outbreaks of gastroenteritis. The report provides an update on guidelines and recommendations for the proper collection of specimens to be sent to CDC, gives general background information concerning some recently discovered pathogens, lists some of the tests available at CDC, and provides a list of CDC contacts. The guidelines and the general information provided on causes of outbreaks of gastroenteritis can be also used by public health workers for investigations when specific testing is available and appropriate.

To identify the prevalence, seasonality and demographic characteristics of patients with viral gastroenteritis, we reviewed 6 years of retrospective data on viral agents of gastroenteritis screened by electron microscopy at 10 centers in the United States and Canada. From 52,691 individual electron microscopic observations, a virus was detected in 16% of specimens, and the yearly positive detection rate among centers ranged from 8 to 34%. Rotavirus was the agent most commonly observed (26 to 83%), followed by adenoviruses (8 to 27%, respiratory and enteric combined), and small round viruses (SRVs) (0 to 40%) which were second most common at two of the centers. Rotavirus and astrovirus detections occurred more often in the winter but seasonal trends in detection were not apparent for the other viruses. Of all astroviruses detected 64% were found in infants (less than 1 year); unlike the other agents studied SRVs were detected in a large percentage of infants (48%) and older children and adults (20%). Among hospitalized patients a majority of all astroviruses, caliciviruses and SRVs were detected 7 days or more after admission in contrast to both rotaviruses and adenoviruses which were more likely to be detected earlier. The data suggest that SRVs are common agents of gastroenteritis and may be important causes of nosocomial infections. Because of the relative insensitivity of direct electron microscopy as a screening method for SRVs, astroviruses and caliciviruses, these data probably underestimate the true prevalence of disease caused by these agents.

Each year, infectious gastroenteritis causes greater than 210,000 children in the United States to be hospitalized and 4-10 million children to die worldwide. Since the mid-1970s, knowledge has increased dramatically concerning the viral agents that are responsible for much of this public health burden. Rotavirus, the most common cause of diarrhea among children, infects virtually every child in the United States by the age of 4 years and causes potentially lethal dehydration in 0.75% of children less than 2 years of age. Other recently identified pathogens include the enteric adenoviruses, calicivirus, astrovirus, and the Norwalk family of agents. Conclusive diagnosis of these viruses requires electron microscopic examination of stool specimens, a laboratory technique that is available only at a few large centers, including CDC. Stool samples from an outbreak that are submitted to CDC for detection of viral pathology should be collected in bulk from 10 ill persons during their first 48 hours of illness, while feces are still liquid, and should be stored at 4 C (not frozen). Acute- and convalescent-phase serum samples should be collected from the same persons, plus from an equal number of controls, during the first week of illness and 3 weeks thereafter. Control measures for outbreaks of viral gastroenteritis should focus on the removal of an ongoing common source of infection (e.g., an ill food handler or the contamination of a water supply) and on the interruption of person-to-person transmission that can perpetuate an outbreak in a population after the common source has been removed. Because improvements in environmental hygiene may not be accompanied by reductions of endemic diarrhea caused by viruses, immunization may play an important role in future control; vaccine trials for rotavirus are in progress. In anticipation of vaccine development and use, CDC recently began national surveillance for the viral agents of gastroenteritis. Health-care facilities involved in the detection of rotavirus or the other viral agents of diarrhea can participate.

Data from 34 studies of the etiology of childhood diarrhoea were compiled in order to investigate the seasonal patterns of rotavirus gastroenteritis and consider their implications for transmission of the virus. Rotavirus was detected in 11-71% of children with diarrhoea, and the median rate of detection (33%) was independent of the level of economic development or geographical region of the study area, as well as of the method of detection used. While rotavirus infections have been called a winter disease in the temperate zones, we found that their incidence peaked in winter primarily in the Americas and that peaks in the autumn or spring are common in other parts of the world. In the tropics, the seasonality of such infections is less distinct and within 10 degrees latitude (north or south) of the equator, eight of the ten locations exhibited no seasonal trend. Throughout most of the world, rotavirus is present all the year round, which suggests that low-level transmission could maintain the chain of infection. The virus is spread by the faecal-oral route but airborne or droplet transmission has also been postulated. The epidemiology of rotavirus--its seasonality in the cooler months, its universal spread in temperate and tropical zones in developed and less developed settings--more closely resembles that of childhood viruses that are spread by the respiratory route (such as measles) than that of common enteric pathogens that are spread predominantly by the faecal-oral route.