PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Immunization Programs”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

Vaccine distribution: an operations research study.

The implementation of an immunization program in rural areas is affected by lacunae in the vaccine distribution system. A study conducted in India identified the extent to which irregular supply of vaccines has affected the immunization program. This study also identified other problem areas, such as a faulty cold chain and the need for an improved monitoring and control system and for better supervision. A model was designed to represent the immunization program and was used to assess the performance of the system under different supply conditions and operational policies. The study identified a number of improvements that could be made in the vaccine distribution system.

Humans↗

[Program of quality assurance at the primary level of health care].

Health care quality assurance is an increasing demand of our social environmental, regarding not only high medical technology centers but, even more so, the services given at the primary care level, that covers the greater part of the population. In this paper we describe a quality assurance program implemented through "quality circles" within the immunization program of a primary health care center. The study was done in several stages. In the first two steps (preliminary diagnosis of the local immunization program, and coverage evaluation) the main problems affecting the program's quality were identified. In turn, these results allowed the implementation of the next phases: integration of the quality circles, elaboration of a quality assurance manual, and actual operation of the quality circles. A methodology first developed in a third level care institution was applied in this quality assurance program, which, on the other hand, showed immediate benefits on the services rendered.

Humans↗

Recent trends in pediatric Haemophilus influenzae type B infections in Canada. Immunization Monitoring Program, Active (IMPACT) of the Canadian Paediatric Society and the Laboratory Centre for Disease Control.

OBJECTIVE: To describe changes in the number of cases of Haemophilus influenzae type b (Hib) infections among Canadian children before and after the introductory phases of Hib vaccination. DESIGN: Multicentre case series. SETTING: All 10 pediatric tertiary care centres across Canada participating in the Immunization Monitoring Program, Active (IMPACT) of the Canadian Paediatric Society and the Laboratory Centre for Disease control. PATIENTS: Children with a Hib infection admitted to any of the participating hospitals from 1985 to 1994. Annual case totals from 1985 to 1990 were determined from records of hospital laboratories or coded discharge diagnoses, or both. From 1991 to 1994 intensive case surveillance was conducted on the wards in addition to thorough record searches as above. OUTCOME MEASURES: Estimated annual case totals for 1985-90. For 1991-94 intensive surveillance for quarterly case totals, yearly age distribution of cases, and proportion of recent cases that represent vaccination failures or missed opportunities to prevent infection. RESULTS: The total number of Hib cases from 1985 to 1990 was 2095; from 1991 to 1994, there were 326 laboratory-confirmed cases and 15 probably cases supported by Hib antigen detection. The annual number of cases declined from an estimated 485 in 1985 to 24 in 1994, a decrease of 95.1%. The steepest interannual decrease (63.7%) occurred between 1992 and 1993, following the introduction of infant-based vaccination programs across Canada. The number of Hib cases involving children most at risk (those 6 to 18 months old) decreased from 78 in 1991 to 4 in 1994. Of the 24 cases in 1994, 6 were categorized as preventable, 1 was fatal, and 8 were vaccine failures (2 of which involved currently used vaccines). CONCLUSION: The prevalence of Hib infections reported by the IMPACT centres has declined greatly since the introduction of vaccination programs. However, deaths and complications continue to occur, attesting to the need to vaccinate all eligible infants and children against this virulent pathogen.

Age Distribution↗

Global control of vaccine-preventable diseases: how progress can be evaluated.

In the developing world, excluding China, less than 40% of infants receive a third dose of diphtheria-tetanus-pertussis or poliovirus vaccines. More than 3 million children still die annually from measles, neonatal tetanus, and pertussis, while more than a quarter of a million children are crippled by poliomyelitis. Acceleration of existing efforts, with the use of approaches that must differ according to the requirements of individual countries, constitutes the overriding priority for the Expanded Programme on Immunization (EPI). In evaluating immunization programs, priority should be placed on monitoring immunization coverage and disease incidence. Routine reports are essential for this purpose, although they may usefully be supplemented by surveys. The problems revealed by an evaluation of immunization programs can be taken as being generic to the health services as a whole, until proven otherwise. Therefore, in remedying these problems, approaches that improve the health services as a whole should be sought.

Communicable Disease Control↗

Should yellow fever vaccine be included in the expanded program of immunization in Africa? A cost-effectiveness analysis for Nigeria.

The cost-effectiveness of preventive yellow fever vaccination versus emergency mass vaccination campaigns for epidemic control remains a matter of controversy. Until recently, Nigeria and other anglophone countries in West Africa most severely afflicted by yellow fever epidemics have followed a policy of emergency control. The effects of including yellow fever 17D vaccine in the Expanded Program of Immunization (EPI) on the immune status of the Nigerian population was studied under conservative assumptions of vaccine coverage and efficacy. The model defined the age-specific prevalence of immunity resulting from vaccination of infants and from natural endemic infection beginning in 1991 and extending over a time horizon of 35 years. The data were used to predict the number of cases and deaths during hypothetical epidemics in 2006 and 2026, representing the historic periodicity of epidemics. A second model was used to demonstrate that a > or = 60% prevalence of immunity would preclude epidemic yellow fever transmission; under base case assumptions, this prevalence would be reached after 18 years of initiating routine yellow fever vaccination in the Guinea savannah zone, the region most often affected by epidemics. Using assumptions based on data from other African countries, the cost of adding yellow fever vaccine to the existing EPI was estimated as +0.65 per fully immunized child, whereas the cost of emergency vaccination in the face of an epidemic was estimated as +7.84/person. Vaccine coverage rates achievable by the EPI were modeled on recent successes with measles vaccine, and began in 1991 at 60%. The effective vaccine coverage rate in an emergency campaign was taken as 10%, based on recent experience. For an epidemic of moderate size in 2006 (morbidity similar to the documented outbreak in 1987), the cost-effectiveness of emergency mass immunization for control of hypothetical yellow fever epidemics was two-fold higher ($381/case and $1,904/death prevented) than that of the EPI ($763/case and $3,817/death prevented). However, despite its higher cost, the efficiency of the EPI was seven-fold greater in terms of cases and deaths prevented. In large epidemics, such as that occurring over successive years (1986-1991) in Nigeria, cost-effectiveness of the EPI exceeded that of emergency control. The EPI may also play an important role in the prevention of endemic yellow fever. Assuming annual rates of endemic yellow fever predicted by serologic surveys, routine vaccination would significantly reduce morbidity and mortality at cost-effectiveness ratios within the range for other diseases prevented by the EPI, including polio, tetanus, and diphtheria.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

No more kidding around: restructuring non-medical childhood immunization exemptions to ensure public health protection.

Professor Silverman's article examines the complex challenges faced by U.S. policymakers attempting to balance the public health protections of mandatory childhood immunization programs with the legal, religious, philosophical, and practical concerns raised by permitting non-medical exemptions under the programs. The article begins with a discussion of the history of childhood immunization programs, and continues by describing the inconsistency of enforcement of state immunization laws and exemptions. The author analyzes recent cases from New York, Wyoming, and Arkansas, and discusses how these decisions both pose threats to these programs' public health protections, while also offering insight into potential problems for other state vaccination programs. Professor Silverman concludes by advocating that states adopt an "informed refusal" approach to vaccination exemption as a way of improving immunity protections, while respecting the autonomy rights of those who wish to opt out of the program.

Child↗

Hepatitis B virus epidemiology, disease burden, treatment, and current and emerging prevention and control measures.

Hepatitis B virus (HBV) infection is a serious global health problem, with 2 billion people infected worldwide, and 350 million suffering from chronic HBV infection. The 10th leading cause of death worldwide, HBV infections result in 500 000 to 1.2 million deaths per year caused by chronic hepatitis, cirrhosis, and hepatocellular carcinoma; the last accounts for 320 000 deaths per year. In Western countries, the disease is relatively rare and acquired primarily in adulthood, whereas in Asia and most of Africa, chronic HBV infection is common and usually acquired perinatally or in childhood. More efficacious treatments, mass immunization programs, and safe injection techniques are essential for eliminating HBV infection and reducing global HBV-related morbidity and mortality. Safe and effective vaccines against HBV infection have been available since 1982. The implementation of mass immunization programs, which have been recommended by the World Health Organization since 1991, have dramatically decreased the incidence of HBV infection among infants, children, and adolescents in many countries. However, not all countries have adopted these recommendations and there remains a large number of persons that were infected with HBV prior to the implementation of immunization programs. Antiviral treatment is the only way to reduce morbidity and mortality from chronic HBV infection. Conventional interferon alfa and lamivudine have been the primary treatments to date. Conventional interferon alfa produces a durable response in a moderate proportion of patients but has undesirable side-effects and must be administered subcutaneously three times per week. Lamivudine also produces a response in a modest proportion of patients and causes few side-effects. However, prolonged treatment is often necessary to prevent relapse on cessation of therapy, and continuous treatment can lead to the development of lamivudine resistance. Promising emerging new treatments include adefovir, entecavir and peginterferon alfa-2a (40 kDa).

Antiviral Agents↗

Scalable single-cell total RNA-seq reveals non-coding programs in immunity, infection, and brain development.

Non-coding RNAs represent a widespread and diverse layer of post-transcriptional regulation across cell types and states, yet much of their diversity remains uncharted at single-cell resolution. This gap stems from the limitations of widely used single-cell RNA-sequencing protocols, which focus on polyadenylated transcripts and miss many short or non-polyadenylated RNAs. Here, we adapted single-cell RNA-sequencing on the 10x Genomics platform to capture a broad complement of coding and non-coding RNAs-including miRNAs, tRNAs, lncRNAs, histone RNAs, and non-adenylated viral transcripts. This approach enabled the discovery of rich, dynamic non-coding RNA programs across immune cells, virally infected hepatocytes, and the developing human brain. In dengue virus-infected hepatocytes, we detect non-adenylated viral transcripts and distinguish active from transcriptionally quiescent infected states, each with distinct host regulatory signatures. In brain tissue, we identify biotype-specific, cell-type-restricted non-coding RNAs, including miRNAs whose expression anticorrelates with predicted targets, consistent with post-transcriptional regulatory relationships. We show that MIR137, one of the strongest GWAS loci associated with schizophrenia and intellectual disability, is expressed specifically in Cajal-Retzius cells, an early-born but transient population that guides subsequent cortical neuron migration. These findings demonstrate the importance of non-coding RNAs in defining cell identity and state, and show how expanded transcriptome coverage can reveal additional layers of gene control-now accessible through practical and scalable single-cell profiling.

Journal Article↗

A pilot study of the effectiveness of a school-based influenza vaccination program.

OBJECTIVE: The objective of this study was to evaluate the feasibility of a school-based influenza immunization program. METHODS: Pupils and their families from 3 demographically similar elementary schools participated in this pilot, unblinded, controlled intervention study. Live attenuated influenza vaccine (FluMist) was made available to all eligible pupils in 1 target school during regular school hours. Two schools where vaccine was not offered served as control schools. All families from the 3 study schools were sent an anonymous questionnaire requesting 7-day recall data on fever or respiratory illness (FRI)-related medical visits, medications purchased, and days of school or paid work lost during the peak influenza week. Changes in weekly pupil absenteeism were also examined. RESULTS: One hundred eighty-five (40%) of the target school pupils received vaccine, of whom >50% were vaccinated < or =3 weeks before the influenza outbreak period. Questionnaires were returned by 43% to 51% of households. Significant (45-70%) relative reductions in FRI-related outcomes, including doctor visits by adults or children, prescription or other medicines purchased, and family schooldays or workdays missed, were observed for target school households, compared with control school households. The increases in absenteeism rates during the influenza outbreak period, compared with baseline rates earlier in the fall, were not significantly different between target and control schools. Within the target school, however, the increase in absenteeism rates was significantly smaller for the FluMist-vaccinated pupils, compared with the non-FluMist-vaccinated pupils. CONCLUSIONS: This school-based influenza immunization program was associated with significant reductions in FRI-related outcomes in households of pupils attending an intervention school. These results might have underestimated the potential impact of FluMist, because the majority of children received intraepidemic vaccination.

Absenteeism↗

Pertussis immunization in the global pertussis initiative international region: recommended strategies and implementation considerations.

Despite widespread immunization programs in most countries, pertussis disease continues to be a threat to public health. In particular, there has been a resurgence of pertussis disease in older children, adolescents and adults, creating a reservoir of infection, which poses a significant threat to infants who are either unimmunized or incompletely immunized. Global Pertussis Initiative participants from Argentina, Australia, Brazil and Japan considered the relative merits of several strategies to reduce the burden of pertussis disease and suggested strategies that might be implemented in these countries. Infants in these countries receive an initial course of 3 doses of vaccine in the first year of life followed by a fourth dose in the second year. Only children in Japan are not given a preschool booster (age 3-5 years). Of the strategies considered, the addition of a preschool booster is therefore a priority in Japan to overcome the problem of waning vaccine-induced immunity to pertussis in school children. Waning immunity also affects adolescents; Australia introduced an adolescent booster in 2003, and the addition of a booster in this age group was suggested for Argentina and Japan. Immunization of new mothers and other close contacts of young infants, such as child care and health care workers, might be appropriate in Australia in the future. Argentina also suggested a future possibility of immunizing health care and child care workers. Obstacles to new immunization strategies include poor access to standardized laboratory diagnostic techniques, inadequate resources to fund new immunization programs, low awareness of pertussis disease in adults and adolescents and inadequate surveillance techniques to assess the full extent of the problems caused by pertussis or the impact new vaccination strategies might have.

Adolescent↗

St. Thomas Immunization Initiative. A student-run community action project.

The objectives of the St Thomas Immunization Initiative are to provide a clinical community medicine experience for first- and second-year medical students, expose students to a community immunization program, teach students the principles of a community immunization program, and demonstrate a working relationship between the residents of an underserved community and medical students. From 1993 to 1995, first- and second-year students at Tulane University Medical School participated in class projects known as Shots for Tots and the St Thomas Immunization Initiative. Students received instruction about immunizations and administered vaccinations to children and adults in low-income neighborhoods. A total of 754 immunizations were administered to 331 children from 1993 to 1995. Participating students were surveyed and 82% of those who responded to a questionnaire felt that the project benefited the community it served while 79% felt that they personally benefitted from participating in the project. Given their experience, 96% of the students would be more likely to participate in a community development project in the future.

Adult↗

The value of immunization against hepatitis A.

Safe and effective inactivated vaccines should soon be available for prevention of hepatitis A virus infections in the United States. Here we review the heterogeneous distribution of hepatitis A cases among different risk groups, age groups, and geographic regions of the United States and comment on several possible strategies for using hepatitis A vaccines in immunization programs. We conclude that immunization targeted exclusively at groups that are at high risk of developing hepatitis A is unlikely to significantly lower national rates of the disease. While universal immunization of young children may accomplish this goal, such a practice is likely to prove unacceptably costly. Alternative strategies worthy of consideration include immunization targeted to specific risk groups on a regional basis, based on knowledge of the local epidemiology of hepatitis A.

Child↗

Immunization outreach using individual need assessments of adults at an army hospital.

A comprehensive assessment of the immunization status of 2,451 adults was carried out at Walter Reed Army Medical Center's Allergy-Clinical Immunology Service, Washington, DC, during an influenza immunization program from October 1985 through February 1986. More than 66 percent of those screened needed either immunization other than for influenza, or an immunologic test, a decline from 72 percent noted during a 1984-85 influenza immunization program. The mean number of interventions was 2.00 per patient in the 1985-86 program and 2.26 during the previous program. Of patients screened in the period 1985-86, 20.5 percent received diphtheria-tetanus toxoids, 15.7 percent received pneumococcal vaccine, and 23.1 percent received a tuberculin skin test. Vaccination or titers for measles were ordered for 10.4 percent, for rubella for 10.9 percent, and for hepatitis B for 20.3 percent. Assessment of those who came to the clinic for influenza vaccination in the second program demonstrated that the needs of some patients had been met in the first program. However, a general lack of immune protection existed in the majority of patients screened in the second program. In both programs, those older than 59 years needed pneumococcal vaccine and diphtheria-tetanus toxoids more frequently than the general population. The means of the numbers of interventions and the percentages of patients needing intervention other than influenza vaccine declined from the first program to the second, suggesting progress in meeting some individual immunization needs in a large and changing ambulatory population.

Adult↗

Potential strategies to reduce the burden of pertussis.

Pertussis continues to be a significant cause of morbidity and mortality among nonimmunized young infants. Although the inception of childhood pertussis immunization programs has significantly reduced the occurrence of the disease in children, waning vaccine-induced immunity permits the disease to affect adolescents and adults, who in turn transmit the disease to unimmunized or incompletely immunized infants. The Global Pertussis Initiative brought together experts from 17 countries around the world to evaluate strategies to improve disease control. Seven strategies were considered: (1) universal adult immunization; (2) selective immunization of mothers and close family contacts of newborns; (3) selective immunization of health care workers; (4) selective immunization of child care workers; (5) universal immunization of adolescents; (6) preschool booster at 4-6 years of age; and (7) reinforcement and/or improvement of current infant and toddler immunization strategies. Because immunization programs vary widely from country to country, no single strategy is likely to be appropriate for all. Moreover it would be helpful to have additional data to support the strategies and provide a better understanding of the disease so that new approaches can be monitored effectively. However, certain steps can be taken now to reduce the incidence of pertussis.

Adolescent↗

Economic analysis of the 1996-1997 mass measles immunization campaigns in South Africa.

To evaluate economic implications of conducting a "catch-up" measles vaccination campaign, we conducted an economic analysis of the 1996-1997 measles immunization campaign in two provinces of South Africa comparing the baseline two-dose routine immunization program to the combined vaccination strategy (routine two-dose immunization program, plus the 1996-1997 campaign). The study findings indicate that the 1996-1997 mass measles immunization campaign was cost-effective in both study provinces, and cost-saving in the province with higher pre-campaign disease incidence and lower routine vaccination coverage. An early investment in effective vaccination strategies that rapidly reduce disease burden apparently results in better returns, both epidemiologically and economically.

Adolescent↗

Assessing immunization performance of private practitioners in Maine: impact of the assessment, feedback, incentives, and exchange strategy.

INTRODUCTION: A provider-based vaccination strategy that has strong supportive evidence of efficacy at raising immunization coverage level is known as Assessment, Feedback, Incentives, and Exchange. The Maine Immunization Program, and the Maine Chapter of the American Academy of Pediatrics collaborated on the implementation and evaluation of this strategy among private providers. METHODS: Between November 1994 and June 1996, the Maine Immunization Program conducted baseline immunization assessments of all private practices administering childhood vaccines to children 24 to 35 months of age. Coverage level assessments were conducted using the Clinic Assessment Software Application. Follow-up assessments were among the largest practices, delivering 80% of all vaccines. RESULTS: Of the 231 practices, 58 were pediatric and 149 were family practices. The median up-to-date vaccination coverages among all providers for 3 doses of diphtheria-tetanus-pertussis vaccine and 2 doses of oral polio vaccine, and 4 doses of diphtheria-tetanus-pertussis vaccine, 3 doses of oral polio vaccine, and 1 dose of measles-mumps-rubella vaccine at age 12 and 24 months were 90% and 78%, respectively, and did not vary by number of providers in a practice or by specialty. Urban practices had higher coverage than rural practices at 12 months (92% vs 88%). The median up-to-date coverage for 4 doses of diphtheria-tetanus-pertussis vaccine, 3 doses of oral polio vaccine, and 1 dose of measles-mumps-rubella vaccine at 24 months of age improved significantly among those practices assessed 1 year later (from 78% at baseline to 87% at the second assessment). On average, the assessments required 21/2 person-days of effort. CONCLUSIONS: We document the feasibility and impact of a public/private partnership to improve immunization delivery on a statewide basis. IMPLICATIONS: Other states should consider using public/private partnerships to conduct private practice assessments. More cost-effective methods of assessing immunization coverage levels in private practices are needed.

Child↗

Economic aspects of vaccines and immunizations.

Several techniques are used to estimate whether investing in vaccines and immunization is worthwhile, including cost analysis, cost-benefit analysis, cost-effectiveness analysis, and cost-utility analysis. At least 162 published economic evaluations of vaccines have been carried out from 1969 to 1998. They consistently show that immunization is an excellent investment--highly cost-effective and usually cost-saving--for vaccines that are currently recommended for universal use. Although prices of newer vaccines are higher than prices of traditional vaccines, they are still highly cost-effective. The World Health Organization, UNICEF, and vaccine manufacturers have developed approaches to make newer vaccines available to developing countries at reduced prices. Sustainability of immunization programs (the ability of a country to continue its immunization program in the absence of external support) is an increasingly important goal. However, external assistance will be essential in the short term to ensure that all the world's people benefit fully from the new vaccines.

Cost-Benefit Analysis↗

Development of vaccination policy in Japan: current issues and policy directions.

Until November 2001, eight vaccinations had been offered to Japanese children on a routine basis; namely, diphtheria-tetanus-pertussis, polio, measles, rubella, Japanese encephalitis, and BCG. The 2001 amendment of the Immunization Law introduced an influenza vaccine for the elderly population. This paper reviews the progress of the immunization program in the broader context of infectious disease control in Japan. There are two recent major policy changes in the field of infectious disease control in Japan. One is the strengthening and revitalization of the infectious disease control program, particularly surveillance, by the enactment of new 1999 legislation entitled "Law concerning the Prevention of Infectious Diseases and Patients with Infectious Diseases". The other major policy change is a review of existing immunization programs and the amendment of the Immunization Law in 2001. In this article, the present routine vaccination program, as well as the recent amendments to the law, are described. Current policy issues are then discussed, including polio vaccination after the WHO "Zero Polio" announcement in the Western Pacific Region in 2000; strategies for changes in measles, rubella, tuberculosis, and influenza control; as well as adverse reaction monitoring/surveillance and feedback for improving vaccine safety. Finally, the future prospects of intended/planned changes in the vaccination policy are considered.

Age Distribution↗