Control of adenovirus acute respiratory disease in U.S. Army trainees.
(73/1242)
Although limited almost exclusively to military trainees, acute respiratory disease (ARD) caused by adenovirus types 4 and 7 had been the leading cause of hospitalization in U.S. Army personnel. This decrease which resembles influenza in clinical manifestations led to hospitalization of as many as 50% of military trainees in midwinter and imposed a heavy burden on military hospitals and training programs. In studies undertaken from 1965 to 1970, live adenovirus type 4 and subsequently type 7 vaccines were found to be safe and immunogenic and to confer protection against type specific adenovirus ARD. For the past 5 yr. military trainees have been immunized with both adenovirus vaccines during periods of expected adenovirus disease. Since 1966, use of adenovirus vaccines has been monitored through the adenovirus surveillance program which yields weekly data on incidence and etiology of ARD in basic combat trainees. Since 1973, stable adenovirus vaccines have resulted in excellent control of adenovirus ARD. Potential problems with this immunization program are discussed. (+info)
F-cells in the adult: normal values and levels in individuals with hereditary and acquired elevations of Hb F.
(74/1242)
Specific antibodies to human fetal hemoglobin were prepared and, after conjugation with a fluorescent dye, were used to determine the distribution of Hb F-containing cells in blood smears from normal adults and individuals with hereditary and acquired conditions associated with abnormal levels of Hb F. The mean proportion of F-cells in normal persons was 2.7% +/- 1.4%, with a range of 0.5%-7.0%. Proportions of F-cells were increased in persons with several acquired and inherited disorders that are associated with an increased percentage of Hb F in hemolysates. A strong linear correlation between the amount of Hb F and proportion of F-cells was observed. This technique may prove useful in studies of a variety of disorders associated with Hb F elevations and also in investigations of the mechanisms controlling the transition from fetal to adult hemoglobin during the course of human development. (+info)
Improving the monitoring of immunization services in Kyrgyzstan.
(75/1242)
Following the disbanding of the Soviet Union in 1991, the government of Kyrgyzstan was unable to maintain the previous level of health services. To revitalize the health services, the Ministry of Health (MOH) first focused on improving their immunization services, including the immunization component of the Health Management Information System (HMIS). Secondly, to increase immunization coverage, the MOH set as a priority the elimination of prescribing false contraindications to immunization. To accomplish both goals, the MOH updated the national immunization policies and established a more effective structure for managing immunization services. To support the MOH, the US Agency for International Development (USAID) Resources for Child Health (REACH) and Basic Support for Institutionalizing Child Survival (BASICS) projects provided technical assistance through a resident coordinator and consultants, and by organizing an international seminar. The improvements extended beyond systems and forms, but, instead, emphasized monitoring by the frontline health worker and supervising the quality of health information. To accomplish their objectives, the MOH appointed a Working Group to define the problems, revise record-keeping procedures, and develop monitoring tools. This group, representing both national and local levels, was composed of MOH epidemiologists, paediatricians and a management information specialist. To reduce the burden of excessive record-keeping and reporting requirements, the Working Group identified four key indicators for the service delivery level: (1) DPT3 immunization coverage rates for children less than 1 year of age; (2) contraindication rates for DPT; (3) usage of DPT vaccine; and (4) daily refrigerator temperatures. Additional indicators were included at district and provincial levels. After a successful 1-year trial, the MOH implemented the revised HMIS nationally. Not only did the quality of the information system improve, but the new approach provided visible evidence, from facility to national levels, that the MOH was approaching their objective of reducing contraindication rates for DPT immunizations to 5% or less, and that vaccine wastage could be substantially reduced. The project demonstrated that giving health workers the basic epidemiologic skills to monitor their own work measurably improved the quality of the data, and by acquiring the new skills, the workers developed a sense of pride in their work. (+info)
Influence of adrenaline on the dissemination of antibody-producing cells from the spleen.
(76/1242)
Plaque-forming cells (PFC) and rosette-forming cells (RFC) were quantificated in splenic venous and splenic arterial blood and in spleen suspensions of guinea-pigs during a secondary immune response to sheep red blood cells (SRBC). The splenic veno-arterial differences in content of PFC and RFC were determined, indicating whether there had been a release of such cells from the spleen into the blood. The effect of an intracardial injection of adrenaline on the release of immune lymphocytes was investigated. In immunized control animals a splenic release of antigen-binding and antibody-forming cells was found, the release being restricted to the peak of the immune response in the spleen. However, after exogenous adrenaline a considerably increased release of both antigen-binding and antibody-forming cells occurred during a longer period of the immune response. Thus, adrenaline caused an enormous release of PFC from the spleen into the blood on day 4 of the secondary immune response, resulting in a diminished number of PFC remaining in the spleen after the treatment. A physiological significance of an adrenaline-induced dissemination of immune lymphocytes in the body during an immune response to a severe infectious disease is suggested. (+info)
Clinical and immunological risk factors associated with Haemophilus influenzae type b conjugate vaccine failure in childhood.
(77/1242)
Haemophilus influenzae type b (Hib) conjugate vaccines have proved extremely efficacious in healthy children. True Hib vaccine failures are rare. Hib conjugate vaccines were introduced for routine immunization in the United Kingdom and the Republic of Ireland in 1992. Coincident with this, active prospective and national surveillance via pediatricians, microbiologists, and public health physicians was commenced to assess the clinical and immunological factors associated with vaccine failure. During the 6 years of the study, 115 children with true vaccine failure were reported. Of the children who were vaccinated before 12 months of age, a clinical risk factor was detected in 20%, an immunological deficiency was detected in 30%, and one or both were detected in 44%. Children who were vaccinated after 12 months of age were more likely to have one or both factors (67%). Thirty percent (33 of 105) of children with true vaccine failure had a low Hib antibody response (concentration, <1.0 microg/mL) after disease, but the majority then responded to a further dose of Hib vaccine. Children who develop Hib disease despite vaccination deserve further clinical and immunological evaluation. (+info)
The sero-epidemiology of diphtheria in Western Europe. ESEN Project. European Sero-Epidemiology Network.
(78/1242)
Seven countries in Western Europe collected large, representative serum banks across the entire age range and tested them for diphtheria anti-toxin (sample size ranged from 2991 to 7715). Although a variety of assays were used, the results were all standardized to those of a reference laboratory and expressed in international units. The standardization process, and the availability of similar, large data sets allowed comparative analyses to be performed in which a high degree of confidence could be ascribed to observed epidemiological differences. The results showed that there were large differences in the proportion of adults with insufficient levels of protection amongst different countries. For instance, roughly 35% of 50- to 60-year-olds were found to be seronegative (titre < or = 0.01 IU/ml) in Finland compared with 70-75% in the United Kingdom. Furthermore, the proportion of seronegative adults would be expected to increase in some countries, notably Italy and the western part of Germany. In those countries with vaccination of military recruits there was a marked sex-related difference in the proportion of seropositive individuals. All countries have high levels of infant vaccine coverage (> 90%) but the accelerated schedule in the United Kingdom appears to result in lower anti-toxin titres than elsewhere. In Sweden, booster doses are not offered until 10 years of age which results in large numbers of children with inadequate levels of protection. Although the United Kingdom and Sweden both have higher proportions of seronegative children than elsewhere the likelihood of a resurgence of diphtheria in these countries seems remote. (+info)
Do we need to boost pertussis immunization within the existing UK vaccination schedule?
(79/1242)
Pertussis infection is associated with significant morbidity in younger children (<4 years), which can include pneumonia, seizures and encephalopathy. Around one in 250 cases of pertussis in infants under the age of 6 months lead to death or severe brain damage. In the United Kingdom the control of pertussis infection has been based on a three-dose schedule of combined diphtheria, tetanus, whole-cell pertussis vaccine (DTPw) during the first 4 months of life. Coverage rates for primary vaccination are currently at high levels of over 90 per cent and infection rates are relatively low (approximately 1.2 per 100,000). However, there are concerns over the potential under-reporting of pertussis and clear shifts in the age pattern of notified cases are evident, with surveillance data suggesting a possible upward trend in the absolute numbers of infections in those at most risk (i.e. infants <3 months old). The addition of childhood booster dose(s) of pertussis vaccine to the standard schedule has potential clinical benefits and may be cost-effective. Selective adult booster immunization may also have a role to play in controlling the circulation of pertussis. (+info)
Vaccination with empty plasmid DNA or CpG oligonucleotide inhibits diabetes in nonobese diabetic mice: modulation of spontaneous 60-kDa heat shock protein autoimmunity.
(80/1242)
Nonobese diabetic (NOD) mice develop insulitis and diabetes through a process involving autoimmunity to the 60-kDa heat shock protein (HSP60). Treatment of NOD mice with HSP60 or with peptides derived from HSP60 inhibits this diabetogenic process. We now report that NOD diabetes can be inhibited by vaccination with a DNA construct encoding human HSP60, with the pcDNA3 empty vector, or with an oligonucleotide containing the CpG motif. Prevention of diabetes was associated with a decrease in the degree of insulitis and with down-regulation of spontaneous proliferative T cell responses to HSP60 and its peptide p277. Moreover, both the pcDNA3 vector and the CpG oligonucleotide induced specific Abs, primarily of the IgG2b isotype, to HSP60 and p277, and not to other islet Ags (glutamic acid decarboxylase or insulin) or to an unrelated recombinant Ag expressed in bacteria (GST). The IgG2b isotype of the specific Abs together with the decrease in T cell proliferative responses indicate a shift of the autoimmune process to a Th2 type in treated mice. These results suggest that immunostimulation by bacterial DNA motifs can modulate spontaneous HSP60 autoimmunity and inhibit NOD diabetes. (+info)