Implementation Of Immunization Program Research Articles

Immunization safety: A global priority – a major contribution of Canada's international immunization efforts

Immunization safety: A global priority – a major contribution of Canada's international immunization efforts

From Cannes 1993 to the present

In 1993 the Viral Hepatitis Prevention Board focused its attention on the serious threat hepatitis B poses to the community at large. The Cannes 1993 meeting “Action towards control of hepatitis B as a community health risk” was the first initiative and the springboard for other activities. The rationale behind universal hepatitis B vaccination strategies and the prerequisites for implementing these strategies were analyzed. Background information on country-specific hepatitis B epidemiology and on the feasibility of vaccination strategies were presented and discussed. The congress participants concluded that it is insufficient and ineffective to focus a vaccination campaign on a limited subset of the population (the so-called `risk groups'), and the need for universal hepatitis B immunization was clearly recognized. Since Cannes 1993 many countries have responded to the call for universal hepatitis B immunization. Many have performed economic evaluation studies, while others have initiated sero-epidemiological studies to generate input data for burden of disease calculation. These studies indicate that epidemiological and economic arguments cannot be used to delay the implementation of universal hepatitis B vaccination. Some countries have improved their surveillance systems and included viral hepatitis in the surveillance programmes. Others have put hepatitis B on the political agenda. Where are we now? In the six years since the Global Advisory Group of the Expanded Programme on Immunisation set 1997 as the target for integrating HB vaccination into national immunization programmes world-wide, more than 90 countries have included hepatitis B vaccine as part of their routine infant or adolescent immunisation programmes. In the WHO European Region, Albania, Bulgaria, France, Germany, Italy, Luxembourg, Moldova, Poland, Portugal, Romania, Slovenia and Spain have implemented universal vaccination programmes. Belgium, Greece, the Netherlands, Switzerland, Turkey and several other European countries are seriously studying the issues or are making budgetary provisions for the introduction of HB into their vaccination programmes. Most of the European countries which now use the vaccine routinely have started with adolescent immunization. Italy and France have begun with both adolescent and infant HB immunization. The rewards of effective implementation of immunization programmes in these countries are becoming apparent and their success offers an exemplary model for other countries. The deadline was 1997! In Europe, work remains to be done before interventions that will bring us closer to the WHO goal of universal immunization and to the goal of controlling hepatitis B in the community are implemented. To this end, the VHPB has continuously supported the efforts of countries in Europe to meet the WHO target by convening meetings of international experts and issuing publications on the prevention and control of viral hepatitis.

The preterm infant's antibody response to a combined diphtheria, tetanus, acellular pertussis and hepatitis B vaccine

Several combined vaccines have recently been developed, in order to improve the implementation of immunization programmes and increase the coverage for each vaccine. As the response of preterm infants may vary depending on the vaccination schedule and the vaccine product, it should be evaluated specifically as new vaccines become available. In this study we have examined the antibody response to a combined diphtheria, tetanus, acellular pertussis, and hepatitis B vaccine (DTPa-HBV), given as a primary vaccination course at 3, 5 and 11 months of postnatal age, in 34 preterm infants (mean gestational age (GA) = 32.0 weeks) in comparison with 28 term infants. At the end of the primary course, preterm infants had antibody concentrations for pertussis 69 kDa antigen and diphtheria toxoid that were significantly lower than those of term infants; preterm infants with GA≤31 weeks had antibody concentrations for pertussis 69 kDa antigen and HBsAg that were significantly lower than those of preterm infants with higher GA; anti-HBs antibody levels correlated with GA. However, the combined DTPa-HBV vaccine elicited seroconversion to all its components in all but two infants, one term and one preterm, after the second dose and a total seroconversion after the third dose. We conclude that preterm infants may be immunized with a combined DTPa-HBV vaccine, starting at the same chronological age, as term infants.

Pseudomonas Aeruginosa in Hospitalized Patients with Infective Exacerbations of Bronchiectasis: Clinical and Research Implications

<i>Pseudomonas Aeruginosa</i> in Hospitalized Patients with Infective Exacerbations of Bronchiectasis: Clinical and Research Implications

Improving vaccine supplies to rural India

Although children's health can benefit greatly from immunization against infectious diseases, implementation of immunization programs creates problems of a managerial nature. In this study, conducted in rural India, results of data analysis showed that a major problem in implementation of immunization policy for DPT/polio was irregular supply of vaccines from the manufacturers to the regional supply depot, and hence to primary health centers (PHCs) and subcenters. This problem was compounded by the shortage of refrigeration facilities for keeping stocks at appropriate temperatures and the staffs need to have a steady, rather than fluctuating, workload. Staff also needed to predict how much stock to keep at various distribution points in order to satisfy anticipated demand by the target population. A model was designed to incorporate these various elements and to demonstrate the effects of different supply and demand conditions. Results from many simulation runs showed that lower target levels for immunization coverage did not reduce the extent of buffer stocks required: keeping buffer stocks at the PHCs and removing seasonality of supply from the manufacturers were both useful ways of improving coverage. It is suggested that a model such as this could enable more informed decisions by managers and could also be used for other types of vaccines and other supply and demand conditions.