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 1,225 records · Page 68Linked to original sources

Cost benefit analysis of Haemophilus influenzae type b vaccination programme in Israel.

STUDY OBJECTIVE: The recent availability of Haemophilus influenzae type b (HIB) conjugate vaccines prompted an examination of the costs and benefits of four and three dose HIB prevention programmes targeting all newborns in Israel. MEASUREMENTS AND MAIN RESULTS: A four dose programme would reduce the number of childhood (aged 0-13) HIB cases from 184.2 to 31.3 per year, yielding a benefit ($1.03 million) to cost ($3.55 million) ratio of just 0.29/l for health services only, based on a vaccine price of $7.74 per dose. When benefits resulting from a reduction in mild handicaps and severe neurological sequelae are included, the benefit ($4.48 million) to cost ratio rises to 1.26/l and it reaches 1.45/l when the $0.66 million indirect benefits of reduced work absences and mortality are also included. Break even vaccine costs are $2.24 when health service benefits only are considered and $11.21 when all the benefits are included. CONCLUSION: In the absence of other projects with higher benefit to cost ratios, Israel should start to provide a nationwide HIB vaccination programme since the monetary benefits to society of such a programme will exceed the costs to society. A barrier to implementation may occur, however, because the costs of the programme exceed the benefits to the health services alone.

Adolescent↗

Viral vaccines and antivirals: current use and future prospects.

The evolution of viral vaccines from the time of Jennerian prophylaxis to today's recombinant technology has been a continuing story of success. From the relatively crude or "first generation" vaccines for smallpox, rabies, and yellow fever followed a second and third generation of improved or new viral vaccines. The application of techniques for attenuating, inactivating, and partially purifying candidate viruses yielded safe, effective vaccines against influenza, poliomyelitis, measles, mumps, and rubella. With the advent of effective national immunization programs in the United States and other areas of the world to promote wide scale use of these vaccines, we have seen a dramatic decrease in incidence of the viral infections of childhood. The new biotechnology serves as the cornerstone for a fourth generation of vaccines and has already provided a licensed recombinant yeast human hepatitis B vaccine. The prospects for a wide spectrum of new or improved vaccines are highly encouraging, not only because of the recent technical advances but also because vaccine development has been recognized as a priority area of research. Under the National Institute of Allergy and Infectious Diseases' Program for Accelerated Development of New Vaccines, support is being provided for developmental vaccine studies with hepatitis A and B, influenza A and B, rabies, rotavirus, varicella, and respiratory syncytial virus (53). The outlook for antivirals is equally optimistic. The same technologies that have provided greater insight into the genetics and molecular biology of viruses and hence the means to fashion subunit or even synthetic vaccines have yielded data that can be applied to successful development of targeted antiviral compounds.

Antiviral Agents↗

[New indications for the inactivated influenza vaccine in the pediatric population (2004-2005)].

Several epidemiological studies have indicated that, in all countries and in distinct epidemic years, the highest rates of influenza infection (between 15% and 42%) occur in the pediatric population, especially in school-aged children. Over various influenza seasons, the rates of annual outpatient visits attributable to influenza vary from 6-29% of children. Influenza and its complications have been reported to result in a 10-30% increase in the number of antibiotic courses prescribed to children during the influenza season. Current percentages of influenza vaccination in children are very low, although the hospitalization rates for infectious complications in children under 5 years are at least equal to those observed in individuals aged more than 65 years. The reasons for these low immunization rates are unknown, but many factors could be involved, especially the need for annual revaccination. In 2003 the Advisory Committee on Immunization Practices (ACIP) recommended influenza immunization only in children at high risk for influenza complications and in those living with someone in a high-risk group. However, they encouraged vaccination of all children aged 6-23 months old. After a review of various epidemiological studies, in 2004 both the ACIP and the American Academy of Pediatrics recommended systematic immunization of all healthy children within this age group. However, both institutions advise that before the routine introduction of influenza immunization in all children aged 6-23 months old, immunization programs in high-risk children need to be implemented.

Adolescent↗

[Evaluation of the immunity level achieved with the oral polio vaccine in schoolchildren aged 6 to 12 years of Catalonia (Spain)].

BACKGROUND AND OBJECTIVE: To evaluate the immunity level achieved with oral polio vaccine in schoolchildren aged 6-12 years of Catalonia (Spain). SUBJECTS AND METHOD: The prevalence of antibodies against poliovirus 1, 2 and 3 was investigated using the neutralizing technique in a representative (n = 197) sample of schoolchildren aged 6-12 years of Catalonia (Spain) obtained in 2001. RESULTS: The prevalence of antibodies was 94.4% for poliovirus 1; 98.5% for poliovirus 2, y 73.1% for poliovirus 3. 93.4% of serum samples had antibodies against poliovirus 1 and 2; 70.6% against poliovirus 1 and 3, and 69.5% against poliovirus 1, 2 and 3. The prevalence of antibodies was similar in different socio-demographic groups. Schoolchildren who had been vaccinated (5 doses) had a higher level of antibodies against poliovirus 3 than those who had not completed vaccination (4 or less doses): 75.4% vs 50.0% (p < 0.05). The prevalence of antibodies against poliovirus 1 and 2 was similar in schoolchildren completing and not completing vaccination. CONCLUSIONS: Results obtained in this study show that 26.9% of schoolchildren aged 6-12 years do not have an adequate immunity level against poliovirus 3 with the oral polio vaccine, being it necessary to develop an immunization program using the inactivated polio vaccine.

Antibodies, Viral↗

Lack of association of A/NJ/76 (swine flu) vaccine and polymyositis.

There is no indication of an increase in the number of cases of polymyositis/dermatomyositis observed and reported among the 43.3 million civilians who received the A/NJ/76 (swine flu) vaccine from October 1 to December 16, 1976, in the United States. Among nearly 1 million Army and Navy personnel who received the vaccine, there was no increase in the incidence rate of polymyositis/dermatomyositis. Furthermore, there was no indication of an increase in the number of cases of polymyositis/dermatomyositis diagnosed at the Mayo Clinic, the Cleveland Clinic, the Cleveland Metropolitan Hospital or the Massachusetts General Hospital during or following the national immunization program in 1976.

Dermatomyositis↗

Improvements in immunization compliance using a computerized tracking system for inner city clinics.

Vaccination compliance rates were calculated for 1995 to 2001 for enrolled patients, based on the Centers for Disease Control and Prevention guidelines and age-appropriate vaccine schedules. The results reported here indicate computerized tracking with the Doctor's Pediatric Immunization Program (Dr. PIP) maintained vaccine compliance rates (> 90%) in healthy and immunocompromised children at 2 months and 12 months of age. Instituting the computerized system has yielded nearly optimal results in both indigenous inner-city clinics. Despite the efficient progress made by automated tracking, the results for specific vaccine strategies (Varicella) and target groups (human immunodeficiency virus, high-risk indigent populations) may require on-going and intensive educational efforts to achieve optimization levels.

Adolescent↗

Rationale for use of Tdap booster vaccines for adolescent immunization: overview of efficacy, safety, and clinical use.

Pertussis is one of the only vaccine-preventable diseases with increasing incidence in the United States. The incidence of pertussis infection in adolescents is a growing concern; it can be a severe disease that may lead to significant morbidity and mortality when transmitted to susceptible populations (eg, infants). Experts have conceded that booster vaccination of adolescents may considerably decrease the incidence of pertussis infections in previously immunized, partially immunized, and nonimmunized populations. Studies in 2 tetanus, diphtheria, and acellular pertussis (Tdap) booster vaccines licensed by the Food and Drug Administration (FDA) have shown efficacy against pertussis disease and have demonstrated a safety profile comparable to tetanus and diphtheria vaccine (Td) in adolescents. Immunization schedules now include use of Tdap vaccines for preadolescent and adolescent populations to counter the increase in pertussis outbreaks. Challenges for clinicians include prompt recognition of pertussis symptoms, proper diagnosis using appropriate tools, and timely reporting of pertussis infections to surveillance bodies. Additional studies are needed to monitor trends of pertussis incidence after implementing the new vaccination schedule for adolescents.

Adolescent↗

Risk factors for delay in age-appropriate vaccination.

OBJECTIVE: To estimate the risk factors of children experiencing delay in age-appropriate vaccination using a nationally representative population of children, and to compare risk factors for vaccination delay with those based on up-to-date vaccination status models. METHODS: The authors compared predictors of delay in age-appropriate vaccination with those for children who were not up-to-date, using a nationally representative sample of children from five years of pooled data (1992-1996) from the National Health Interview Survey (NHIS) Immunization Supplement. Duration of delay was calculated for the DTP4, Polio3, MMR1 doses and 4:3:1 series using age-appropriate vaccination standards; up-to-date status (i.e., whether or not a dose was received) was also determined. Adjusted odds ratios were estimated using multivariate logistic regression for models of vaccination delay and up-to-date vaccination status. RESULTS: Absence of a two-parent household, large family size, parental education, Medicaid enrollment, absence of a usual provider, no insurance coverage, and households without a telephone were significantly related to increased odds of a child experiencing vaccination delay (p < or = 0.05). CONCLUSIONS: Many of the risk factors observed in models of vaccination delay were not found to be significant in risk models based upon up-to-date status. Consequently, risk models of delays in age-appropriate vaccination may foster identification of children at increased risk for inadequate vaccination. Populations at increased risk of inadequate vaccination can be more clearly identified through risk models of delays in age-appropriate vaccination.

Age Factors↗

Vaccine coverage levels after implementation of a middle school vaccination requirement, Florida, 1997-2000.

OBJECTIVE: Little information is available about the effectiveness of school entry vaccination requirements at the middle school level. This study examined coverage levels among students entering seventh grade in Florida following implementation of a school entry vaccination requirement in 1997. METHODS: The authors analyzed county-specific vaccination coverage levels (three doses of hepatitis B vaccine, a second dose of measles, mumps, and rubella [MMR] vaccine, and a booster dose of tetanus and diphtheria toxoids [Td]) among students entering public and private schools in Florida from 1997 through 2000. In 1998, a survey of all county health departments was conducted, and the resulting data were linked to county-specific vaccination rates. RESULTS: During the 1997-1998 school year, the first year the requirement went into effect, at school entry 121,219 seventh-grade students (61.8%) were fully vaccinated, 72,275 seventh grade students (36.9%) lacked one or more doses of vaccine but were considered in process, 1,817 were non-compliant (0.9%), and 763 had medical or religious exemptions (0.4%). In the 2000-2001 school year, the proportions of students reported fully vaccinated at school entry had increased to 66%. Most of this change was related to an increase in hepatitis B coverage. There was a significant inverse relationship between the proportion of students fully vaccinated and the size of the county's seventh grade population. CONCLUSIONS: The seventh grade vaccination entry requirement was associated with sustained high levels of vaccination coverage. Passing a school entry vaccination requirement appears may be sufficient to increase coverage, but other strategies may be required to achieve full immunization of middle school students.

Adolescent↗

Pneumococcal vaccination: current and future issues.

Infection with Streptococcus pneumoniae remains a major global health burden meaning the development of effective vaccines is urgently needed. The current 23-valent polysaccharide vaccine has been shown to prevent pneumococcal pneumonia in immunocompetent young adults, but not in elderly persons. However, in prevention of invasive pneumococcal disease, the vaccine is efficacious in the elderly and may also be effective in some groups of immunocompromised patients. The polysaccharide vaccine is, therefore, recommended in all older (> or = 55-65 yrs of age) adults and in young children (>2 yrs of age) who have a high risk for pneumococcal disease. Revaccination can be safely performed and is recommended 5 yrs after the first dose. In children <2 yrs of age, the new polysaccharide-protein conjugate vaccines, including 7-11 serotypes, seem to be effective in the prevention of invasive disease, severe pneumonia and serotype-specific (and vaccine-related types) otitis media. The low serotype coverage, need for repeated doses, and high price, may decrease the usefulness of the new conjugates. However, the included serotypes correspond to those most often associated with penicillin resistance and vaccination is, therefore, a possible tool in limiting the spread of antibiotic-resistant pneumococci.

Adolescent↗

Immediate and longer term impact of the varicella shortage on children 18 and 24 months of age in a community population.

BACKGROUND: Little is known about the impact of the recent varicella vaccine shortage. To assess the temporal trend in varicella vaccine administration before 18 and 24 months of age in a community cohort of children prior to, during and after the recent varicella vaccine shortage. And to compare the temporal trends in varicella vaccinations to trends of an older, more widely accepted vaccine, the MMR. METHODS: Community population-based birth cohorts were identified who were eligible for the varicella vaccination before, during and after the 2001 to 2002 varicella vaccine shortage. Only children (84% of all) who remained in the community through their second birthday were included. For each child in the cohort, the medical records and immunization registry records from both medical facilities in the county were reviewed to identify the dates and sites for all varicella immunizations given. In addition to varicella immunizations, the dates of all MMR vaccinations were recorded. Additional data abstracted included the child's birth date, gender and dates of any recognized cases of chickenpox up through age 24 months. RESULTS: Of the 2,512 children in the birth cohorts, 50.8% were boys. In the three cohorts combined, 81.1% of the boys and 79.3% of the girls (p = 0.30) received the varicella vaccine by age 24 months. The pre-shortage community rate of varicella immunization was 79.7% by 24 months of age. During the varicella vaccine shortage, the rate of varicella immunization by 24 months fell to 77.2%. Only 6 additional children received a "catch-up" immunization by 36 months of age. In the post shortage period the community 24-month immunization rate rebounded to a level higher than the pre-shortage rate 84.0%. During the almost three years of observation, the MMR immunization rate by age 24 months was constant (87%). CONCLUSION: The varicella shortage was associated with an immediate drop in the 24-month varicella immunizations rate but rebounded quickly to above pre-shortage rates. In this community the only long term impact of the varicella vaccine shortage may be on the small number of children who still had not received catch-up varicella immunizations by 36 months of age.

Age Distribution↗

Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review.

BACKGROUND: In Canada--a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, complex, and changing. This systematic review aimed to 1) estimate age-specific prevalence of HAV antibody in Canada and 2) evaluate infection-associated risk factors. METHODS: MEDLINE (1966-2005) and EMBASE (1980-2005) were searched to identify relevant studies for the systematic review. Archives for the Canada Diseases Weekly Report (1975-1991) and Canada Communicable Disease Report (1992-2005) were searched for relevant public health reports. Data were abstracted for study and participants' characteristics, age-specific prevalence, and risk factors. RESULTS: A total of 36 reports describing 34 unique studies were included.The seroprevalence in Canadian-born children was approximately 1% in ages 8-13, 1-6% in 20-24, 10% in 25-29, 17% in 30-39, and increased subsequently. In age groups below 20 and 20-29, age-specific seroprevalence generally remained constant for studies conducted across geographic areas and over time. Compared to Canadian-born individuals, subjects born outside Canada were approximately 6 times more likely to be seropositive (relative risk: 5.7 [95% CI 3.6, 9.0]). Travel to high risk areas in individuals aged 20-39 was associated with a significant increase in anti-HAV seropositivity (RR 2.8 [1.4, 5.5]). Compared to heterosexuals, men having sex with men were only at a marginally higher risk (adjusted odds ratio 2.4 [0.9, 6.1]). High risk for seropositivity was also observed for Canadian First Nations and Inuit populations. CONCLUSION: Results from the current systematic review show that in this low endemicity country, disease acquisition occurs in adulthood rather than childhood. The burden of disease is high; approximately 1 in 10 Canadians had been infected by ages 24-29. The increase in prevalence in young adults coincides with disease importation and increasing frequency of risk factors, most likely behavioral-related ones. Gaps in seroprevalence data were identified rendering the application of current immunization recommendations difficult. A nationwide prevalence survey for all Canadians is needed. This is essential to quantify the effectiveness of current recommendations and conduct cost-effectiveness evaluations of alternative immunization programs, if necessary.

Age Factors↗

A mass vaccination campaign targeting adults and children to prevent typhoid fever in Hechi; expanding the use of Vi polysaccharide vaccine in southeast China: a cluster-randomized trial.

BACKGROUND: One of the goals of this study was to learn the coverage, safety and logistics of a mass vaccination campaign against typhoid fever in children and adults using locally produced typhoid Vi polysaccharide (PS) and group A meningococcal PS vaccines in southern China. METHODS: The vaccination campaign targeted 118,588 persons in Hechi, Guangxi Province, aged between 5 to 60 years, in 2003. The study area was divided into 107 geographic clusters, which were randomly allocated to receive one of the single-dose parenteral vaccines. All aspects regarding vaccination logistics, feasibility and safety were documented and systematically recorded. Results of the logistics, feasibility and safety are reported. RESULTS: The campaign lasted 5 weeks and the overall vaccination coverage was 78%. On average, the 30 vaccine teams gave immunizations on 23 days. Vaccine rates were higher in those aged < or = 15 years (90%) than in adolescents and young adults (70%). Planned mop-up activities increased the coverage by 17%. The overall vaccine wastage was 11%. The cold chain was maintained and documented. 66 individuals reported of adverse events out of all vaccinees, where fever (21%), malaise (19%) and local redness (19%) were the major symptoms; no life-threatening event occurred. Three needle-sharp events were reported. CONCLUSION: The mass immunization proved feasible and safe, and vaccine coverage was high. Emphasis should be placed on: injection safety measures, community involvement and incorporation of mop-up strategies into any vaccination campaign. School-based and all-age Vi mass immunizations programs are potentially important public health strategies for prevention of typhoid fever in high-risk populations in southern China.

Adolescent↗

Gene transfer in experimental medicine.

Gene transfer technology has many potential applications in medicine. Phase I and phase II gene-based clinical trials have been conducted for the treatment of cancer, monogenic disorders, some neurodegenerative illnesses, cardiopathies and infectious diseases. A phase I gene therapy clinical trial has recently been approved for the treatment of Parkinson's disease, while preclinical studies are in progress to develop gene-based interventions for the treatment of Alzheimer's disease and Huntington's disease, amyotrophic lateral sclerosis, spinal cord injury, and diabetes type 1 and type 2. A number of gene transfer models have been generated for gene therapy and genetic immunization programs. Vector design is addressing several pressing issues in the matter of gene delivery improvement, stabilization of transgene expression and safety. This is necessary in order to achieve efficient gene-based therapeutic interventions. Indeed, considerable progress has been reported in the field of vector design, which has produced some encouraging results in clinical trials and preclinical studies. However, vector design should be further developed to allow for the successful application of gene transfer technology in therapy. This review summarizes the latest achievements and controversies in clinical trials and preclinical studies in the field of gene therapy.

Animals↗

Veterans Administration cooperative study on hepatitis and dentistry.

Personnel in the VA dental facilities were screened for the detection of viral hepatitis and identification of factors implicating infectivity. A total of 963 personnel from 126 dental facilities throughout the United States voluntarily participated in the study. The rate of seroconversion for any hepatitis B markers was approximately 1% per year. Serial positive tests for antibody to hepatitis B core antigen or antibody to hepatitis B surface antigen (or both) were present in 16.2% of dentists and 13.0% of dental auxiliary personnel. Oral and maxillofacial surgeons composed the highest prevalence occupation (24.0%), and clinical personnel composed the lowest prevalence occupation (8.9%). There was a significant association between years in dental environment and serological positivity for viral B infection. The dentists and dental auxiliary personnel had significant linear trends of increasing serological positivity with years in the dental environment. Although a majority of personnel reported wearing gloves while treating high-risk patients or performing invasive procedures, inadequate prophylactic measures were exercised for most patients undergoing a variety of less invasive procedures. The results of the study show the need for an active immunization program against type B viral infection for dental and dental auxiliary personnel, preferably before the initial exposure to the professional environment.

Dental Auxiliaries↗

Prevention of influenza in the general population.

BACKGROUND: Although all jurisdictions in Canada offer annual influenza immunization to people at high risk of complications, only Ontario has provided universal annual immunization of healthy adults and children. Use of chemotherapy (amantidine, neuraminidase inhibitors) to prevent influenza varies among provinces. We sought to systematically review the evidence for the prevention of influenza infection in the general population. METHODS: The interventions reviewed were influenza vaccination and prophylactic use of neuraminidase inhibitors. The health outcomes of interest were rates of laboratory-confirmed influenza infection, clinical definitions of influenza-like illness and work absenteeism. MEDLINE and Cochrane databases were searched for relevant articles published between 1966 and March 2003. Only randomized controlled trials (RCTs) were selected. Evidence was appraised using the methodology of the Canadian Task Force on Preventive Health Care. RESULTS: Eighteen trials involving more than 33,000 healthy adults were identified that met the inclusion criteria; of these, 15 showed that influenza vaccination with either live-attenuated and inactivated vaccines was efficacious. Eleven trials were considered to be of "good" quality, and 7 were considered to be of "fair" quality. The relative risk reduction (RRR) associated with influenza immunization in adults ranged from 0% to 91%. Fifteen RCTs involving more than 45,000 healthy children aged 6 months to 19 years were identified, of which 9 were considered to contain "good" evidence and 6 "fair" evidence. Results from 12 of these trials showed protection against influenza. The RRR ranged from 0% to 93%. There were 6 RCTs of "good" quality showing that neuraminidase inhibitors are effective in preventing influenza infection. Side effects from both influenza vaccination and neuraminidase inhibitor administration were mild. INTERPRETATION: There are numerous RCTs of good quality in large populations that have consistently shown that influenza vaccination, using inactivated or live-attenuated vaccines, is moderately effective in preventing influenza in the general population (healthy adults and children over 6 months of age). There is good evidence that neuraminidase inhibitor prophylaxis in contacts given within 36 to 48 hours of symptom onset of the household index case is effective; appropriate use of this prevention method requires access to rapid diagnostic methods. Decisions about introduction of routine immunization programs must take into account the cost and cost-effectiveness of a universal program and the burden of illness associated with influenza in each jurisdiction.

Absenteeism↗