The inception, achievements, and implications of the China GAVI Alliance Project on Hepatitis B Immunization.

The China GAVI Hepatitis B Immunization Project was initiated in 2002 with the signing of a Memorandum of Understanding between GAVI and the Government of China. The Project was one of the three (China, India, and Indonesia) GAVI-initiated special projects done to support countries too large to receive full GAVI support for hepatitis B vaccine and safe injections. The Project in China was designed by the Chinese Government and partners to deliver free hepatitis B vaccine and safe injections to all newborns in the 12 Western Provinces and Poverty Counties in 10 Provinces of Central China (1301 Counties with approximately 5.6 million births per year), eliminating the gap in immunization coverage between wealthier and poorer regions of China. The project budget (USD 76 million) was equally shared by GAVI and the Chinese Government. Initially planned for 5 years, two no cost extensions extended the project to 2011. Although China produced hepatitis B vaccine, before the project the vaccine was sold to parents who were also charged a "user fee" for the syringe and vaccine administration. Basic Expanded Program on Immunization (EPI) vaccines such as BCG, DTP, Polio, and measles vaccines were provided free to parents, although they were charged a user fee. Vaccines were sold by China CDC Offices at provincial, prefecture, county level and township hospitals, and village doctors received a substantial portion of their income from the sale of hepatitis B and other vaccines. The result of charging for hepatitis B vaccine was that coverage was relatively high in Eastern and wealthier counties in Central China (~80-90%), but was much lower (~40%) in Western China and Poverty Counties where parents could not afford the vaccine. The Project was administered by the China MOH and China CDC EPI program, and two Project Co-managers, one from the Chinese Government and the other an international assignee, were chosen. The project had an oversight Operational Advisory Group composed of the Chinese Government, WHO, UNICEF, and GAVI. The initial targets of the project as delineated in the initial MOU for the Project areas (HepB3 coverage will reach 85% at the county level, >75% of newborns at the county level will receive the first dose of hepatitis B within 24h of birth, and all immunization injections will be with auto disable [AD] syringes) were substantially exceeded. The differential in vaccine coverage between wealthier and poorer parts of China was eliminated contributing to a great improvement in equity. With additional contributions of the Chinese Government the Project was accomplished substantially under budget allowing for additional catch up immunization of children under 15 years of age. More than 5 million health workers were trained in how to deliver hepatitis B vaccine, timely birth dose (TBD), and safe injections, and public awareness of hepatitis B and its prevention rose significantly. TBD coverage was expedited by concurrent efforts to have women deliver in township clinics and district hospitals instead of at home. The effective management of the Project, with a Project office sitting within the China EPI and an Operational Advisory Group for oversight, could serve as a model for other GAVI projects worldwide. Most importantly, the carrier rate in Chinese children less than 5 years of age has fallen to 1%, from a level of 10% before the inception of the Project. Liver cancer, one of the major cancer killers in China (250,000-300,000 annual estimated deaths), will dramatically decline as immunized cohorts of Chinese children age. While hepatitis C and non-alcoholic liver disease also exist in China and can lead to liver cancer and cirrhosis, the majority of liver disease in China is hepatitis B related and therefore preventable. The authors believe that China's success in preventing hepatitis B is one of the greatest public health achievements of the 21st century. Work remains to be done in several key areas. There are still pockets of home births in rural provinces where a TBD is difficult to deliver, and China is strengthening its policy of screening pregnant women for HBsAg and delivering HBIG plus vaccine to newborns of HBV carrier mothers. Approximately 10% of the adult population of China remain chronic carriers of hepatitis B virus and cannot be helped by the vaccine, so prevention of liver cancer and cirrhosis in those groups remains a future challenge for China.

The immunization data quality audit: verifying the quality and consistency of immunization monitoring systems.

OBJECTIVE: To evaluate the consistency and quality of immunization monitoring systems in 27 countries during 2002-03 using standardized data quality audits (DQAs) that had been launched within the framework of the Global Alliance for Vaccines and Immunization. METHODS: The consistency of reporting systems was estimated by determining the proportion of third doses of diphtheria-tetanuspertussis (DTP-3) vaccine reported as being administered that could be verified by written documentation at health facilities and districts. The quality of monitoring systems was measured using quality indices for different components of the monitoring systems. These indices were applied to each level of the health service (health unit, district and national). FINDINGS: The proportion of verified DTP-3 doses was lower than 85% in 16 countries. Difficulties in verifying the doses administered often arose at the peripheral level of the health service, usually as the result of discrepancies in information between health units and their corresponding districts or because completed recording forms were not available from health units. All countries had weaknesses in their monitoring systems; these included the inconsistent use of monitoring charts; inadequate monitoring of vaccine stocks, injection supplies and adverse events; unsafe computer practices; and poor monitoring of completeness and timeliness of reporting. CONCLUSION: Inconsistencies in immunization data occur in many countries, hampering their ability to manage their immunization programmes. Countries should use these findings to strengthen monitoring systems so that data can reliably guide programme activities. The DQA is an innovative tool that provides a way to independently assess the quality of immunization monitoring systems at all levels of a health service and serves as a point of entry to make improvements. It provides a useful example for other global health initiatives.

Rubella seropositivity in the United States, 1988-1994.

Data obtained in the third National Health and Nutrition Examination Survey (NHANES III), conducted during 1988-1994, were analyzed to determine the epidemiology of rubella seropositivity in the United States, including risk factors for low rubella seropositivity. Serological samples obtained from NHANES III study participants > or =6 years of age were tested for rubella IgG antibodies. "Rubella seropositivity" was defined as serum rubella IgG antibody level > or =10 IU by enzyme immunoassay. Overall, rubella seropositivity rates in the United States were 92% in persons aged 6-11 years, 83% in persons aged 12-19 years, 85% in persons aged 20-29 years, 89% in persons aged 30-39 years, and >or =93% in persons aged > or =40 years. The lowest rate (78%) of any United States birth cohort of the 20th century occurred among persons born from 1970-1974. Eliminating rubella and chronic rubella syndrome in the United States will require international efforts, including vaccination of preschool- and school-age children and all susceptible young adults.

National serologic survey of measles immunity among persons 6 years of age or older, 1988-1994.

CONTEXT: Measles incidence in the United States is at a record low, and indigenous transmission has been interrupted in each year since 1996, suggesting that measles is no longer endemic. A national estimate of measles immunity and an understanding of predictors of measles susceptibility are essential for assuring sustained elimination of endemic disease. OBJECTIVE: To assess patterns of immunity and to determine predictors of susceptibility to measles. DESIGN/SETTING: Sera and data on participants from the third National Health and Nutrition Examination Survey (1988-1994) (NHANES III) were examined. NHANES III was a cross-sectional survey of a representative sample of the civilian, noninstitutionalized population of the United States. POPULATION: 20,100 persons 6 years of age or older were tested for measles-specific immunoglobulin G (IgG) antibody by an enzyme immunoassay. MAIN OUTCOME MEASURE: Participants with serum positive for measles antibody were considered protected or immune to measles disease. RESULTS: Prevalence of measles immunity was 93%. Nearly all persons (99%) born in the prevaccine era (before 1957) were immune. Immunity declined among persons born in the vaccine era (after 1956) to 81% among those born in 1967-1976, and increased again to 89% among those born in 1977-1988. Among persons born in the vaccine era, independent predictors of measles susceptibility varied by birth cohort and included birth in the United States, residence in a noncrowded household, residence in a nonmetropolitan area, and, among males, non-Hispanic white and Mexican American race/ethnicity. Among adults 17 years of age or older, additional predictors of susceptibility included living at or above the poverty line and not currently being married. CONCLUSIONS: Population immunity among persons 6 years of age or older is very high; however, as many as 15 million persons across the United States may lack humoral immunity. While it is unclear that the susceptible population can support continuous, indigenous transmission of measles, providers should follow current recommendations to evaluate the measles susceptibility of patients born in the vaccine era and vaccinate eligible patients.

Economic evaluation of use of diphtheria, tetanus, and acellular pertussis vaccine or diphtheria, tetanus, and whole-cell pertussis vaccine in the United States, 1997.

OBJECTIVE: To compare the economic costs and benefits associated with using either diphtheria and tetanus toxoids and acellular pertussis vaccine (DTaP) or diphtheria and tetanus toxoids and whole-cell pertussis vaccine (DTwP) in the United States in 1997. DESIGN: Standard cost-benefit analysis, from both the societal and health care system perspectives, was performed for each combination vaccine as well as for the pertussis components singly. SETTING: A simulated cohort of 4.1 million children from birth to age 15 years. MAIN OUTCOME MEASURES: Net costs (savings) and benefit-cost ratios (BCRs) RESULTS: Without a vaccination program, diphtheria, tetanus, and pertussis disease caused more than 3 million cases and more than 28,000 deaths, at a cost of $23.6 billion. From the societal perspective, net savings because of the use of DTaP and DTwP were $22.510 million and $22.623 million, respectively. The net savings from the acellular pertussis component and the whole-cell pertussis component only were $4.362 million and $4.474 million, respectively. Benefit-cost ratios for DTaP from a societal and health care system perspective were 27:1 and 9:1, respectively. Sensitivity analyses of key variables did not result in appreciable changes in results. CONCLUSIONS: Compared with no program, vaccination with DTaP or DTwP resulted in substantial savings, regardless of the perspective taken and for all sensitivity analyses conducted. Compared with DTwP, use of DTaP generated a small cost increase that might be offset by the value of other factors, such as increased confidence in pertussis vaccination resulting from reduced adverse events. Arch Pediatr Adolesc Med. 2000;154:797-803

Widespread paralytic poliomyelitis in Pakistan: A case-control study to determine risk factors and implications for poliomyelitis eradication.

Despite substantial efforts to eradicate poliomyelitis by administering oral poliovirus vaccine through routine immunization and annual national immunization days (NIDs), Pakistan reported 22% (1147) of the worldwide cases in 1997. Reasons for continued high poliomyelitis incidence include failure to vaccinate, vaccine failure, or inadequate immunization strategies. A case-control study was conducted to measure vaccination status and reasons for undervaccination among 66 poliomyelitis cases and 130 age- and neighborhood-matched controls. Cases were undervaccinated through routine immunization (matched odds ratio [MOR], 0.3; 95% confidence interval [CI], 0.1-0.5); however, NID immunization was similar for cases and controls (MOR, 0.6; 95% CI, 0.3-1.2). Reasons for undervaccination included not being informed, considering vaccination unimportant, and long distances to vaccination sites. Failure to vaccinate through routine immunization was a major risk factor for poliomyelitis in Pakistan. Successful NIDs alone will not interrupt poliovirus circulation in Pakistan, and children remain at risk unless routine immunization is strengthened or additional supplementary immunization is provided.

Effectiveness and cost-effectiveness of linking the special supplemental program for women, infants, and children (WIC) and immunization activities.

OBJECTIVE: To raise immunization coverage among children at risk for underimmunization, we evaluated the effectiveness and cost-effectiveness of immunization activities in the Special Supplemental Program for Women, Infants and Children (WIC). METHOD: A controlled intervention trial was conducted in seven WIC sites in Chicago between October 1990 and March 1994. At intervention sites, staff screened children for vaccination status at every visit, referred vaccine-eligible children to either an on-site WIC nurse, on-site clinic, or off-site community provider, and issued either a 3-month supply of food vouchers to up-to-date children or a 1-month supply to children not up-to-date--a usual practice for high-risk WIC children. Our primary measure of effectiveness was the change in the baseline percentage of up-to-date children at the second birthday; cost-effectiveness was approximated for each of the three referral interventions. RESULTS: After one year, up-to-date vaccination coverage increased 23% above baseline for intervention groups and decreased 9% in the control group. After the second year, up-to-date vaccination further increased to 38% above baseline in intervention groups and did not change in the control group. The total cost per additional up-to-date child ranged from $30 for sites referring children off-site to $73 for sites referring children on-site to a nurse. CONCLUSION: This controlled intervention trial of screening, referral, and a voucher incentive in the WIC program demonstrated a substantial increase in immunization coverage at a low cost. Continuing to design linkages between WIC and immunization programs by building on WIC's access to at-risk populations is worth the investment.

A model to estimate the potential economic benefits of measles eradication for the United States.

Measles incidence is at a nadir in many parts of the world due to vaccination efforts. Although the technical feasibility of eradication has been acknowledged, financial and political commitment need to be concomitantly identified on the national and global level. We demonstrate the potential value of measles eradication by identifying the potential cost-savings to one country resulting from measles eradication. For the US, measles eradication would save $45 million annually. If achieved by the year 2010, the US would save $500 million to $4.1 billion depending on the year of elimination, post-eradication schedule and discount rate. Intensification of measles control efforts in the US beyond current levels would have minimal marginal benefits on disease burden reduction. Allocation of resources to achieve global measles eradication is the next level of efficiency which would provide substantial savings. Countries may adapt this model to estimate their savings for consideration of the required political and financial contribution towards a global measles eradication program.

Measles, mumps, and rubella--vaccine use and strategies for elimination of measles, rubella, and congenital rubella syndrome and control of mumps: recommendations of the Advisory Committee on Immunization Practices (ACIP).

These revised recommendations of the Advisory Committee on Immunization Practices (ACIP) on measles, mumps, and rubella prevention supersede recommendations published in 1989 and 1990. This statement summarizes the goals and current strategies for measles, rubella, and congenital rubella syndrome (CRS) elimination and for mumps reduction in the United States. Changes from previous recommendations include: Emphasis on the use of combined MMR vaccine for most indications; A change in the recommended age for routine vaccination to 12-15 months for the first dose of MMR, and to 4-6 years for the second dose of MMR; A recommendation that all states take immediate steps to implement a two dose MMR requirement for school entry and any additional measures needed to ensure that all school-aged children are vaccinated with two doses of MMR by 2001; A clarification of the role of serologic screening to determine immunity; A change in the criteria for determining acceptable evidence of rubella immunity; A recommendation that all persons who work in health-care facilities have acceptable evidence of measles and rubella immunity; Changes in the recommended interval between administration of immune globulin and measles vaccination; and Updated information on adverse events and contraindications, particularly for persons with severe HIV infection, persons with a history of egg allergy or gelatin allergy, persons with a history of thrombocytopenia, and persons receiving steroid therapy.

The interruption of transmission of indigenous measles in the United States during 1993.

BACKGROUND: The United States has a goal to eliminate all indigenous cases of measles by the year 2000. Initial interruption of indigenous measles transmission would be expected during a period of very low measles incidence as occurred during late 1993. METHODS: Indigenous measles cases (i.e. cases acquired in the United States and not traceable to any imported case) from 1993 were investigated to determine their source of infection. The probability of sustained undetected measles transmission between isolated indigenous cases was estimated. RESULTS: Of the 312 measles cases reported for 1993, only 25 (8%) occurred after September 19. Of these only 4 cases (16%) could be classified as indigenous. The estimated probability that any of these 4 cases resulted from indigenous measles transmission in theirs or any adjoining counties was 0.05 or less. CONCLUSIONS: Interruption of indigenous measles transmission appears to have occurred for the first time throughout the United States in 1993. This event provides strong support for the current national strategy for measles elimination. However, complete elimination of indigenous measles will require maintaining high population immunity to prevent spread from imported cases and attaining global measles control to prevent the importation of measles.

Respiratory diphtheria in the United States, 1980 through 1995.

OBJECTIVES: The purpose of this study was to describe the epidemiologic, laboratory, and clinical features of respiratory diphtheria cases reported in the United States during 1980 through 1995. METHODS: Respiratory diphtheria cases reported to the Centers for Disease Control and Prevention were reviewed. Cases were defined as physician-diagnosed cases with signs and symptoms compatible with respiratory diphtheria, including the presence of a pseudomembrane without other apparent cause. RESULTS: From 1980 through 1994, 41 respiratory diphtheria cases were reported; none were reported in 1995, and no secondary cases were identified. Nine (22%) case patients were 4 years of age or younger, and 28 (68%) were 15 years of age or older. None of the case patients were up to date with diphtheria vaccination; 4 unvaccinated children died. Seventeen (43%) of 40 case patients had positive culture results. CONCLUSIONS: Available surveillance data suggest that respiratory diphtheria has become a rare disease in the United States. However, importation and circulation of toxigenic strains continue to present a threat and require achieving and maintaining high coverage with diphtheria toxoid-containing vaccines in both children and adults.

Immunization of adolescents: recommendations of the Advisory Committee on Immunization Practices, the American Academy of Pediatrics, the American Academy of Family Physicians, and the American Medical Association.

This report concerning the immunization of adolescents (ie, persons 11-21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (ie, MMWR 1994;43[No. RR-1] 1-38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians [AAFP]; and AMA Guidelines for Adolescent Preventive Services [GAPS]: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11-12 years of age by establishing a routine visit to their health-care providers. Specifically, the purposes of this visit are to a) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps, and rubella (MMR) vaccine; b) provide a booster dose of tetanus and diphtheria toxoids; c) administer other vaccines that may be recommended for certain adolescents; and d) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine. The most recent recommendations from ACIP, AAP, AAFP, and AMA concerning specific vaccines and delivery of preventive services should be consulted for details.

Effectiveness of the pertussis vaccination program as determined by use of the screening method: United States, 1992-1994.

The screening method was used to evaluate the effectiveness of the pertussis vaccination program in the United States during 1992-1994. The formula VE = 1 - [PCV/(1 - PCV)][(1 - PPV)/PPV] was used (VE = vaccine effectiveness; PCV = proportion of cases vaccinated; PPV = proportion of population vaccinated). Data from the national Supplementary Pertussis Surveillance System and the National Health Interview Survey were used to determine PCV and PPV, respectively. Among children aged 7-18 months, VE for 3 doses of pertussis vaccine was 79% (95% confidence interval, 74%-83%) for preventing culture-confirmed pertussis. Between the ages of 19 and 47 months, VE for > or = 4 doses was 90% (95% confidence interval, 88%-92%). VE estimates appeared lower in epidemic (1993) than non-epidemic years (1992, 1994). VE estimates determined using the screening method were consistent with the previous estimates from the United States. This method will continue to be useful for assessing the effectiveness of the pertussis vaccination program in the United States, where acellular pertussis vaccines are recommended for infants.

Risk of chronic arthropathy among women after rubella vaccination. Vaccine Safety Datalink Team.

CONTEXT: A review by the Institute of Medicine found a possible relationship between rubella vaccination and chronic arthritis among women. OBJECTIVE: To evaluate the risk of persistent joint and neurologic symptoms in rubella seronegative women subsequently vaccinated with RA 27/3 rubella vaccine. DESIGN: Retrospective cohort study based on computerized laboratory data and medical record review. Records were reviewed for symptoms occurring within 2 years before and after the date of serological testing and to identify vaccinees. Possible cases were evaluated by a rheumatologist blinded to serological findings and vaccination status. SETTING: Large health maintenance organization in northern California. PATIENTS: Women aged 15 to 59 years serotested for rubella during 1990 with continuous health plan membership for 2 years before and after the date of their serological test. Seronegative women immunized within 1 year of serotesting (n=971) were defined as exposed. Primary comparison groups included all unvaccinated, seronegative women (n=924) and randomly selected seropositive, unvaccinated women (n=2421) matched to exposed subjects on serological test date and age (+/-3 years). MAIN OUTCOME MEASURES: Prevalence and incidence of chronic joint and neurologic symptoms during 1-year follow-up period stratified by age and serological findings, immunization, and postpartum status. RESULTS: No significantly increased risk was associated with receipt of rubella vaccine for any outcome except for prevalence of carpal tunnel syndrome in vaccinated women at least 30 years old compared with seropositive, unvaccinated women (2.9% vs 1.4%; P=.03). A total of 34 women had onset of conditions within the 1-year follow-up period; 9 of these were in the group of seronegative, immunized women, of whom 6 had onset of symptoms within 6 weeks of vaccination. Among these 6 women, symptoms included transient arthritis or arthralgias (<6 weeks duration) in 4 women, arthralgia of indeterminate chronicity in 1 woman, and carpal tunnel syndrome in 1 woman. Postpartum women across all groups were less likely to be seen for nontraumatic arthropathies than nonpostpartum women (4.5% vs 7.2%, P=.08 in vaccinated women; 4.8% vs 8.1%, P=.09 in seronegative controls; and 4.8% vs 10.0%, P=.01 in seropositive controls). CONCLUSIONS: In this large retrospective cohort analysis there was no evidence of any increased risk of new onset chronic arthropathies or neurologic conditions in women receiving the RA 27/3 rubella vaccine. These data support the continued vaccination of rubella-susceptible women to reduce the risk of congenital rubella syndrome.

Vaccine Safety Datalink project: a new tool for improving vaccine safety monitoring in the United States. The Vaccine Safety Datalink Team.

OBJECTIVE: To fill the large "gaps and limitations" in current scientific knowledge of rare vaccine adverse events identified in recent reviews of the Institute of Medicine. METHODS: Computerized information on immunization, medical outcomes, and potential confounders on more than 500 000 children 0 to 6 years of age is linked annually at several health maintenance organizations to create a large cohort for multiple epidemiologic studies of vaccine safety. RESULTS: Analysis of 3 years of follow-up data shows that 549 488 doses of diphtheria-tetanus-pertussis (DTP) and 310 618 doses of measles-mumps-rubella (MMR) vaccines have been administered to children in the study cohort. Analyses for associations between vaccines and 34 medical outcomes are underway. Screening of automated data shows that seizures are associated with receipt of DTP on the same day (relative risk [RR], 2.1; 95% confidence interval [CI], 1.1 to 4.0) and 8 to 14 days after receipt of MMR (RR, 3.0; 95% CI, 2.1 to 4.2). The diversity of vaccination exposures in this large cohort permits us to show that an apparent association of seizures 8 to 14 days after Haemophilus influenzae type b vaccine (RR, 1.6; 95% CI, 1.2 to 2.1) was attributable to confounding by simultaneous MMR vaccination; the association disappears with appropriate adjustment (RR, 1.0; 95% CI, 0.7 to 1.4). CONCLUSION: Preliminary design, data collection, and analytic capability of the Vaccine Safety Datalink project has been validated by replication of previous known associations between seizures and DTP and MMR vaccines. The diversity in vaccine administration schedules permits potential disentangling of effects of simultaneous and combined vaccinations. The project provides a model of public health-managed care collaborations in addition to an excellent infrastructure for safety and other studies of vaccines.

Trends in importation of measles to the United States, 1986-1994.

OBJECTIVES: To describe patterns among imported measles cases to the United States. DESIGN: Descriptive analysis of national case-based surveillance data on measles cases. SETTING: United States in the period 1986 through 1994. PATIENTS: All reported confirmed cases of measles. MAIN OUTCOME MEASURES: Demographic variables, immunization history, country of exposure, and reporting state. RESULTS: The number of reported imported cases of measles to the United States has dropped from an average of 99 cases annually in 1986 through 1988 and 190 cases in 1989 through 1991 to 61 cases in 1992 through 1994. Since 1990, the number of imported cases originating in Latin America declined by 98%, despite continued increase in the number of travelers to this region; cases from other regions remained relatively constant. This decrease paralleled the rapid decrease in measles incidence in the Western Hemisphere associated with national measles elimination programs. Most imported cases occurred among children, although 22% of cases occurred among young adults. Rates of measles cases per 1 million travelers are higher among non-US citizens than among US citizens. CONCLUSIONS: The sharp decline in importations into the United States from Latin America since 1991 provides evidence of the success of measles control efforts undertaken there. The decrease in imported cases has been associated with a decline in total measles cases in the United States. Sustained elimination of measles in the United States will require improved measles control in other countries in addition to a high level of population immunity.

Risk of hospitalization because of aseptic meningitis after measles-mumps-rubella vaccination in one- to two-year-old children: an analysis of the Vaccine Safety Datalink (VSD) Project.

OBJECTIVE: To assess the level of increased risk, if any, of hospitalizations for aseptic meningitis after Jeryl-Lynn mumps strain measles-mumps-rubella (MMR) vaccine in the Vaccine Safety Datalink population. STUDY DESIGN: A possible increased risk of aseptic meningitis 8 to 14 days after receipt of MMR was observed in a preliminary screening analysis of automated data from the Vaccine Safety Datalink (VSD) project Year 2 analysis. To further evaluate this association a retrospective 10-year matched case-control study was undertaken in the four health maintenance organizations (HMOs) in the VSD project. Cases ascertained from a broad scan of the automated data were validated against a standard case definition. Two controls matched on age, sex, HMO and HMO membership were assigned per case. RESULTS: The VSD project involves the cooperative collection of automated vaccination and medical outcome data from four large HMOs that currently have 500,000 children younger than 7 years of age under surveillance. Review of automated screening results from the first 2 years of data revealed a possible increased risk of aseptic meningitis 0 to 14 days after MMR with a relative risk of 3.61 (95% confidence interval, 1.0 to 13.1) although the total number of cases was small. Although the automated data had suggested a possible association of aseptic meningitis with MMR containing the Jeryl-Lynn strain of mumps, review of validated hospitalized cases during the observation period did not reveal evidence of an increased risk of aseptic meningitis after MMR containing the Jeryl-Lynn strain of mumps (odds ratio < 1.0 for all analyses). CONCLUSION: Although it is recognized that hospitalized cases represent a minority of the total cases of aseptic meningitis, it is reassuring that in this evaluation no increased risk of aseptic meningitis after MMR vaccine was found.

Tetanus surveillance--United States, 1991-1994.

PROBLEM/CONDITION: Despite the widespread availability of a safe and effective vaccine against tetanus, 201 cases of the disease were reported during 1991-1994. Of patients with known illness outcome, the case-fatality rate was 25%. REPORTING PERIOD COVERED: 1991-1994. DESCRIPTION OF SYSTEM: Physician-diagnosed cases of tetanus are reported to local and state health departments, the latter of which reports these cases on a weekly basis to CDC's National Notifiable Disease Surveillance System. Since 1965, state health departments also have submitted supplemental clinical and epidemiologic information to CDC's National Immunization Program. RESULTS: During 1991-1994, 201 cases of tetanus were reported from 40 states, for an average annual incidence of 0.02 cases per 100,000 population. Of the 188 patients for whom age was known, 101 (54%) were aged > or = 60 years and 10 (5%) were aged < 20 years. No cases of neonatal tetanus were reported. Among adults, the risk for tetanus increased with age; the risk for persons aged > or = 80 years was more than 10 times greater than the risk for persons aged 20-29 years. All deaths occurred among persons aged > or = 30 years. The case-fatality rate (overall: 25%) increased with age, from 11% in persons aged 30-49 years to 54% in persons aged > or = 80 years. Only 12% of all patients were reported to have received a primary series of tetanus toxoid before onset of illness. For 77% of patients, tetanus occurred after an acute injury was sustained. Of patients who obtained medical care for their injury, only 43% received tetanus toxoid as part of wound prophylaxis. INTERPRETATION: The epidemiology of reported tetanus in the United States during 1991-1994 was similar to that during the 1980s. Tetanus continued to be a severe disease primarily of older adults who were unvaccinated or inadequately vaccinated. Most tetanus cases occurred after an acute injury was sustained, emphasizing the need for appropriate wound management. ACTIONS TAKEN: In addition to decennial booster doses of tetanus-diphtheria toxoid during adult life, the Advisory Committee on Immunization Practices (ACIP) recommends vaccination visits for adolescents at age 11-12 years and for adults at age 50 years to enable health-care providers to review vaccination histories and administer any needed vaccine. Full implementation of the ACIP recommendations should virtually eliminate the remaining tetanus burden in the United States.

Immunization of adolescents.

This report concerning the immunization of adolescents (i.e., persons 11 to 21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (i.e., MMWR 1994;43[No. RR-1]1-38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians; and AMA Guidelines for Adolescent Preventive Services: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11 to 12 years of age by establishing a routine visit to their health care providers. Specifically, the purposes of this visit are to (1) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps and rubella vaccine; (2) provide a booster dose of tetanus and diphtheria toxoids; (3) administer other vaccines that may be recommended for certain adolescents, and (4) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine.