Novel methods for molecular dynamics simulations

HYPOTHESIS: Monovalent measles vaccine can be administered to children 6 to 11 months of age during an outbreak. Efficacy and effectiveness of this control measure still have to be assessed. METHODS: During and outbreak of measles, monovalent measles vaccine was administered as part of outbreak control to children aged 6 to 11 months. Active surveillance was used to detect cases of measles occurring during the following month. Children who did not develop measles were tested for measles antibody before their revaccination at 15 months of age. RESULTS: Of 81 children 6 to 11 months of age, 56 were vaccinated and two received immunoglobulins; the latter were excluded from the analysis. Measles occurred in 15 of the 79 children during and after the vaccination campaign, for an overall attack rate of 19%. The attack rate among unvaccinated children was 39% (9 of 23), compared with 11% (6 of 56) among those vaccinated (relative risk = 3.6, 95% confidence interval [CI] = 1.5 to 9.1). All of those who sustained measles in the vaccinated group developed the disease within 10 days after vaccination. The overall vaccine effectiveness was 73% (95% CI = 32% to 89%) when children were classified as vaccinated as soon as they were given measles vaccine. It rose to 96% (95% CI = 72% to 99%) when children were considered vaccinated 1 week postimmunization. Nineteen infants who were vaccinated and who did not develop measles during the outbreak were tested for measles antibody status at 15 months of age before revaccination. All had plaque reduction neutralizing antibody titers greater than 120. CONCLUSION: This study confirms that measles vaccination of infants aged 6 to 11 months is an effective intervention measure during measles outbreaks.     

Podiatric casts used for surgery and trauma. Part II: Boot cast

Between April 18 and May 20, 1975, 16 cases of measles occurred in pupils in an elementary school in Baltimore County, Md., and 1 case occurred in a sibling at a junior high school. Measles was serologically confirmed in 16 of these pupils. Attack rates were determined by grade and by vaccine status. The measles attack rate was 2.1 percent for the 377 children who had been given measles vaccine at 1 year of age or later. The rates were 27.8 percent (13 times higher) for those vaccinated at less than 10 months of age and 20.0 percent (10 times higher) for those with no definite history of vaccine. The higher attack rates for children who were vaccinated only before 10 months of age supports the 1972 recommendation of the Public Health Service Advisory Committee on Immunization Practices that children vaccinated before this age need to be revaccinated with live measles virus vaccine to assure full protection. The finding that 2 of 10 children with a history of measles became ill during the outbreak suggests that such histories are not a totally reliable indicator of immunity. Containment of the outbreak was attributed to the high level of immunity in the community and prompt initiation of control measures.     

Mumps epidemic in vaccinated children in West Switzerland

Since 1991, 6 years after the recommendation of universal childhood vaccination against measles, mumps, and rubella (MMR triple vaccine), Switzerland is confronted with a large number of mumps cases affecting both vaccinated and unvaccinated children. Up to 80% of the children suffering from mumps between 1991 and 1995 had previously been vaccinated, the majority with the Rubini vaccine strain. On the basis of a case-control study including 102 patients and 92 controls from the same pediatric population, a study of the humoral immune-response following vaccination with the Rubini vaccine in 6 young adult volunteers, and two different genetic studies, we investigated the complex problem of large scale vaccine failure in Switzerland. We conclude that the recently reported large number of Swiss mumps cases was caused by at least four interacting factors: 1. A vaccine coverage of 90-95% at the age of 2 years is necessary to interrupt mumps wild virus circulation. The nationwide vaccine coverage in Switzerland of some 80% in 27-36 month-old children is too low. 2. Primary vaccine failures (absence of seroconversion or unprotective low levels of neutralizing antibodies), as well as secondary vaccine failures due to the rapid decline of antibodies to mumps virus in our volunteers and controls, seem to be frequent after vaccination with the Rubini strain. 3. Despite its reported Swiss origin, the Rubini strain does not belong to the mumps virus lineages recently circulating in this area but is closely related to American mumps virus strains. 4. Differences in protein structure between the vaccine strain and the circulating wild type strains, and in particular a different neutralization epitope in the hemagglutinin neuraminidase protein, may additionally contribute to the lack of protection in vaccinated individuals.     

Efficacy of measles vaccine during the 1993 measles epidemic in Korea

Immunization to eliminate measles is recommended at 15 months of age with the option of giving vaccine at 6 to 9 months of age during measles outbreaks in Korea. Because of the recent resurgence of measles and concern about the possibility of reduced vaccine efficacy caused by genomic differences between vaccine virus and contemporary wild measles viruses, we conducted a measles vaccine efficacy study involving children with household exposure ages 1 to 5 years during measles outbreak that had occurred 1993 in Seoul and Seong-nam city, with the demographic analysis of patients brought to the hospitals. A total of 380 patients (M:F = 216:164) were included in this study. Two hundred nine cases (55.0%) occurred in children less than 5 years of age, and 167 (43.9%) were younger than 16 months of age. The recorded age-specific incidence rates showed bimodal patterns, i.e. highest peak in those below 16 months of age and second peak in those ages 6 to 9 years of age. Only 9.6% (16 of 167) of the measles cases less than 16 months, 59.5% (25 of 42) of those 16 months to 4 years and 91.8% (157 of 171) of the cases in school age children have been vaccinated. Attack rates among the 122 vaccinated siblings and 12 unvaccinated siblings ages 1 to 5 years who contacted measles were 5.7 and 75%, respectively, and the clinical vaccine efficacy was 92.4% (95% confidence interval, 83.6, 96.4). The high vaccine efficacy in household exposures suggests that measles outbreaks in Korea are not caused by reduced vaccine efficacy.     

Measles outbreaks in the Bern canton

Currently, overall vaccination coverage against measles among infants ranges between 77% and 89% in Switzerland. Experience in other countries has shown that this level of vaccination is not sufficient to prevent measles outbreaks, especially among schoolchildren. During 1992 surveillance for measles outbreaks in closed populations was conducted in the Canton of Berne. Outbreaks were investigated for vaccine efficacy. Two measles outbreaks in schoolchildren were observed during the study period. In 2 Bernese suburban schools 6 measles cases in children (median age 12.5 years) occurred over a period of 37 days. One of the cases had been vaccinated. Vaccination rate in the healthy control children was 89.7%. Estimated vaccine efficacy was 97.7% (95% confidence interval [CI]: 68%, 99%). The second outbreak occurred in a rural region and comprised 21 measles cases (median age 7.5 years) within 43 days. 10 (47.6%) of the cases attended the same school. None of the cases had been vaccinated. Of the healthy control children 82.6% had received measles vaccine. Estimated vaccine efficacy was 100% (CI: 87%, 100%). These two measles outbreaks were due to failure to vaccinate rather than low vaccine efficacy. Surveillance for measles cases is currently not sufficient for the detection of measles outbreaks in our population. Laboratory confirmation of measles, especially in vaccinated persons, has become more important in a time of relatively low measles incidence.     

Hepatitis B virus infection, hepatitis B vaccine, and hepatitis B immune globulin

Hepatitis B virus (HBV) infection is a major health problem in the United States; in 1995, approximately 128,000 cases occurred. Transmission of HBV occurs primarily by blood exchange (eg, by shared needles during injection drug use) and by sexual contact. Persons infected early in life are much more likely to become chronically infected than those infected during adulthood: as many as 90% of infants infected perinatally develop chronic infection and up to 25% will die of HBV-related chronic liver disease as adults. Clinical signs of acute hepatitis occur in about 50% of infected adults but in only 5% of infected preschool-aged children. In the United States, hepatitis B vaccine is currently made by recombinant DNA technology using baker's yeast. Preexposure vaccination results in protective antibody levels in almost all infants and children (> 95%) and healthy adults younger than 40 years of age (> 90%). The most common adverse event following administration of hepatitis B vaccine is pain at the injection site, which occurs in 13% to 29% of adult and 3% to 9% of children. A comprehensive hepatitis B vaccination policy is now recommended that includes (1) routine infant vaccination; (2) catch-up vaccination of 11- to 12-year-olds who were not previously vaccinated; (3) catch-up vaccination of young children at high risk for infection; (4) vaccination of adolescents and adults based on lifestyle or environmental, medical, and occupational situations that place them at risk; and (5) prevention of perinatal HBV infection.     

Long-term persistence of anti-HBs after vaccination with a recombinant DNA yeast-derived hepatitis B vaccine: 8-year results

The aim of this study was to evaluate the persistence of antibodies 7 years after hepatitis B booster administration in healthy adult volunteers who were vaccinated in 1986. In October 1986, 188 seronegative, healthy adult volunteers (117 men and 71 women) were vaccinated with a 20 micrograms dose recombinant DNA yeast-derived hepatitis B vaccine. Mean age of the study group was 23.3 years (+/- 0.28). Immunisation was carried out according to a 0-1-2 month vaccination schedule, with a booster dose at 12 months. Of the 159 subjects who received the full vaccination course, 63 (40%) had a blood sample taken 8 years after the first vaccination. Of these 63 subjects, five were excluded from the analysis due to an irregular vaccination schedule and four subjects did not complete the accompanying questionnaire on possible booster administration. So, 54 subjects remained available for further analysis. Fourteen individuals had received an additional booster of hepatitis B vaccine sometime between 1989 and 1994. The geometric mean titre (GMT) at month 13 for these 14 individuals was 1494 mIU ml-1, compared with 3103 mIU ml-1 for those who did not receive an interim booster. Forty subjects, who received no additional booster dose besides that of month 12, met the inclusion criteria of the follow-up study. Of these, all subjects except one were seropositive for anti-HBs at month 96 (GMT: 215.9 mIU ml-1). All subjects were still anti-HBc negative at that time. Distribution of individual antibody titres revealed that overall 92.5% of subjects retained protective antibody levels (> or = 10 mIU ml-1); 72.5% of vaccinees retained high levels of anti-HBs (> or = 100 mIU ml-1) as compared to 99.2 and 97.0% at month 13, respectively. A positive correlation was found between the subjects' titres at month 13 and month 96. A 0-1-2 dose vaccination course with a booster dose administered at month 12, induces a protective immune response which lasts at least until 7 years after the full vaccination course of the subjects. A positive correlation was found between the anti-HBs antibody titres at month 13 and month 96.     

Abnormalities of measles antibody response in human immunodeficiency virus type 1 (HIV-1) infection

The finding that severe measles occurs in immunized as well as nonimmunized human immunodeficiency virus (HIV)-infected individuals suggests that both immunologic memory and the initial response to measles may be impaired by HIV infection. That the initial response is affected was supported by the finding that post-measles immunization titers of HIV-infected babies were significantly lower (p = 0.01) than those of normal babies. Poor immunologic memory was evidenced in HIV-infected children by lower titers than in normal children (p < 0.001) and by a continuing decline in measles antibody that was not arrested by reimmunization. Impaired memory appeared to be associated with defective avidity maturation. HIV-infected babies and infants or children had a significantly lower avidity index (AI) than age-matched normal children (p < 0.01). HIV-infected adults, who were infected with HIV following infection with measles, did not have AI values significantly different from normal adults (p = 0.18) but had significantly greater values than did HIV-infected babies and children (p < 0.01). Thus, in contrast to infants and children who were infected with HIV before measles immunization, the adult immune response to measles was less affected.     

Influence of the specific T cell response on seroconversion after measles vaccination in autologous bone marrow transplant patients

Six patients who were seronegative to measles after autologous bone marrow transplantation (ABMT) were vaccinated with a live attenuated measles vaccine. The specific T helper cell response was studied by measuring lymphocyte proliferation induced by measles antigen and B cell response by measles specific IgG by ELISA. Blood samples were drawn before, at 1-3 months, and at 1 year after vaccination. It was found that a pre-existing T cell response correlated with an impaired B cell response 1 year after vaccination (r = 0.83, P = 0.04), whereas no correlation was found between IgG titers before vaccination and IgG titer increase, or T cell response after vaccination. Furthermore, there was a transient negative correlation between the T cell response at 1-3 months after vaccination and the T cell response before vaccination (r = -0.90, P = 0.04) that became positive at 1 year after vaccination (r = 0.90, P = 0.02). In conclusion, in patients seronegative to measles who were revaccinated with measles vaccine after ABMT, a pre-existing T cell response correlated with an impaired B cell response, while pre-existing low-level IgG antibodies had no significant influence on the IgG titer rise. A sustained T cell response to measles antigen before vaccination may thus be one possible explanation for measles vaccine failure in ABMT patients.     

Characteristics of pancreatic injury in children: a comparison with such injury in adults

A retrospective study of eight pediatric patients (under 15 years of age) who had pancreatic injuries was undertaken. Comparisons were made with 59 adult patients who sustained pancreatic injuries over the same 15-year period. All the pediatric injuries and 96.6% of the adult resulted from blunt abdominal trauma. Bicycle accidents (children, 75.0%; adults, 0%; P < .001) and automobile accidents (children, 0%; adults, 61.0%; P < .01) were the most common causes of pancreatic injury in the two groups. There was no significant difference in the incidence of abdominal pain or peritoneal irritation between the groups. However, abdominal pain in the adults was poorly localized. Isolated pancreatic injuries were noted in 62.5% of the pediatric patients and in 15.3% of the adult patients (P < .05). Associated intraabdominal injuries were present in 25.0% of the children and in 69.5% of the adults (P < .05). The duodenum was injured in two (25.0%) pediatric patients and in 10 (16.9%) adult patients. Whereas the duodenal injuries in pediatric patients were intramural hematomas without perforation in both cases, all but one of these injuries in adults were perforations or transections (P < .05). There was a significant difference in the type of pancreatic injury between the two groups (P < .05). Surgery was performed in 12.5% of the pediatric cases and in 78.0% of the adult cases (P < .01). There were no deaths among the pediatric patients, but 8.5% of the adults died in the hospital. The difference with respect to clinical course might be related to the differences in cause of injury.     

Epidemiological investigations on measles in unvaccinated and vaccinated children (author's transl)

A national study, with participation of 82 paediatricians, was carried out on 9472 children over medium observation periods of between 3.13 and 5.46 years with evaluation of the history of measles, incidence of complications and details of vaccination procedure performed. The protection rate of primary vaccination with live vaccine was 0.89, with split vaccine (3 times) 0.67 and after a combination of split vaccine (3 times) with live vaccine (9 to 12 months later) 0.94. Complications due to measles in unvaccinated children were found in 5.9% of cases. Measles complications after failure of vaccination were found in 2.9% and 2.8% of children vaccinated with live or split vaccine, respectively. No such complications were observed in children vaccinated with a combination of split and live vaccines.     

Safety and immunogenicity of hepatitis A vaccine in patients with chronic liver disease

Acute hepatitis A superimposed on chronic liver disease (CLD) has been associated with severe or fulminant hepatitis. An open, multicenter study was performed to compare the safety and immunogenicity of an inactivated hepatitis A vaccine in patients with CLD with that in healthy subjects. A secondary objective was to compare the safety of the hepatitis A vaccine with that of a commercial hepatitis B vaccine in subjects with chronic hepatitis C. A total of 475 subjects over the age of 18 years were enrolled into 1 of 5 groups according to history, serological data, and previous diagnosis. Patients in groups 1 (healthy adults), 2 (chronic hepatitis B), 3 (chronic hepatitis C), and 5 (other CLD not caused by viral hepatitis) were vaccinated with two doses of inactivated hepatitis A vaccine, 6 months apart. Patients in group 4 (chronic hepatitis C) received 3 doses of a recombinant hepatitis B vaccine, according to a 0-, 1-, and 6-month schedule. Local injection-site symptoms were the most common reactions reported following vaccination in all groups (35.5% of all doses), with the hepatitis B vaccine eliciting fewer injection-site symptoms than the hepatitis A vaccine (19.8% compared with 37.5%). Although a higher percentage of healthy subjects (93%) seroconverted after a single dose of the hepatitis A vaccine than did subjects with chronic hepatitis C (73.7%) or CLD of nonviral etiologies (83.1%), more than 94% of all vaccinees were seropositive for anti-HAV after the complete vaccination course. At each time point, a lower geometric mean concentration of anti-HAV was observed for each group of CLD patients compared with the healthy control subjects. In conclusion, hepatitis A vaccine was well tolerated and induced a satisfactory immune response in patients with chronic hepatitis B, chronic hepatitis C, and miscellaneous CLD.     

The efficacy of live attenuated, cold-adapted, trivalent, intranasal influenzavirus vaccine in children

BACKGROUND: Influenzavirus vaccine is used infrequently in healthy children, even though the rates of influenza in this group are high. We conducted a multicenter, double-blind, placebo-controlled trial of a live attenuated, cold-adapted, trivalent influenzavirus vaccine in children 15 to 71 months old. METHODS: Two hundred eighty-eight children were assigned to receive one dose of vaccine or placebo given by intranasal spray, and 1314 were assigned to receive two doses approximately 60 days apart. The strains included in the vaccine were antigenically equivalent to those in the inactivated influenzavirus vaccine in use at the time. The subjects were monitored with viral cultures for influenza during the subsequent influenza season. A case of influenza was defined as an illness associated with the isolation of wild-type influenzavirus from respiratory secretions. RESULTS: The intranasal vaccine was accepted and well tolerated. Among children who were initially seronegative, antibody titers increased by a factor of four in 61 to 96 percent, depending on the influenza strain. Culture-positive influenza was significantly less common in the vaccine group (14 cases among 1070 subjects) than the placebo group (95 cases among 532 subjects). The vaccine efficacy was 93 percent (95 percent confidence interval, 88 to 96 percent) against culture-confirmed influenza. Both the one-dose regimen (89 percent efficacy) and the two-dose regimen (94 percent efficacy) were efficacious, and the vaccine was efficacious against both strains of influenza circulating in 1996-1997, A(H3N2) and B. The vaccinated children had significantly fewer febrile illnesses, including 30 percent fewer episodes of febrile otitis media (95 percent confidence interval, 18 to 45 percent; P<0.001). CONCLUSIONS: A live attenuated, cold-adapted influenzavirus vaccine was safe, immunogenic, and effective against influenza A(H3N2) and B in healthy children.     

Impaired response to hepatitis B vaccine in children receiving anticancer chemotherapy

Serologic responses to hepatitis B vaccine were investigated in 197 pediatric cancer patients. The patients, ages 1 to 21 years, comprised 66 with solid tumors, 101 with hematologic malignancies and 30 with various benign conditions. Of them 51 were receiving cytotoxic chemotherapy and 114 had not received chemotherapy for 0.2 to 11 years. Three doses of plasma-derived hepatitis B vaccine (20 micrograms) were given at 0, 1 and 6 months; and antibody concentrations to hepatitis B surface antigen were determined at 3, 6 and 8 months. The geometric mean antibody concentration after 3 vaccine doses was 1076 mIU/ml in cancer patients receiving chemotherapy and 18,833 mIU/ml in cancer patients not receiving chemotherapy. The protective titer of antibody (> or = 10 mIU/ml) was reached after 3 doses of vaccine by 67% of patients receiving chemotherapy and by 97% of those not receiving chemotherapy. The patients being treated for solid tumors had weaker responses than those being treated for hematologic malignancies: after 3 vaccine doses no response was observed in 6 of 11 patients with solid tumors compared with 3 of 25 of patients with hematologic malignancies. Children receiving anticancer chemotherapy have essentially weaker responses to hepatitis B vaccine than children not receiving chemotherapy or those with benign conditions. This reflects the profound immunosuppression during chemotherapy. The effect of more intensive immunization schedules should be investigated.     

Low seroconversion with hepatitis B vaccination in peritoneal dialysis patients

OBJECTIVE: To compare seroconversion using hepatitis B vaccine between hemodialysis (HD) and peritoneal dialysis (PD) patients. DESIGN: Data on PD patients vaccinated were collected retrospectively for the period 1992 to 1995. The data on HD patients were collected prospectively from 1991 to 1994. SETTING: A university outpatient dialysis center. PARTICIPANTS: All adult patients who received all four doses of hepatitis B vaccine while on dialysis were included (47 PD and 50 HD patients). INTERVENTION: Recombinant hepatitis B vaccine (Engerix), 40 micrograms IM was administered at 0, 1, 2, and 6 months. MAIN OUTCOME MEASURE: Seroconversion was measured after completion of the vaccination series. RESULTS: 74% of the HD patients seroconverted compared to 53% of PD patients (p = 0.03). Older, heavier patients compared to all the other patients had a lower seroconversion rate in both the HD patients (55% vs. 78 %) and PD patients (38% vs. 59%) (p = 0.03). CONCLUSION: The seroconversion rate to recombinant hepatitis B vaccine is lower in patients on PD than on HD for unclear reasons. Further studies are required to determine the etiology of this difference.     

Induction of immunologic refractoriness in adults by meningococcal C polysaccharide vaccination

Thirty-four adults were vaccinated with 1/50 of the usual dose of meningococcal polysaccharide vaccine (1 microg of A, C, Y, and W135 polysaccharides, given intramuscularly). This dose was selected as a probe to assess B cell memory. The probe elicited meningococcal C bactericidal antibody responses in all 18 adults who had been vaccinated 4 years earlier with an investigational meningococcal A and C oligosaccharide-protein conjugate vaccine and in the majority of the 11 subjects vaccinated for the first time. In contrast, the responses of the 5 adults given a full dose of licensed polysaccharide vaccine 4 years earlier were <1/10 of those of the other 2 groups. Thus, adults previously given a full dose of meningococcal polysaccharide vaccine show evidence of immunologic refractoriness to group C polysaccharide, whereas refractoriness is not observed after conjugate vaccination. These findings have implications for the use of meningococcal polysaccharide vaccine when the risk of disease is low.     

Comparison of the safety and immunogenicity of the lyophilized Mérieux seed and the World Health Organization working reference BCG vaccines in school-aged children in Senegal

In order to validate two new lots of Mérieux BCG vaccine (Mérieux seed derived from strain 1072), a calibration study was performed to compare their safety and immunogenicity to a full dose of the WHO-reference BCG vaccine (Tokyo strain 172) as well as the WHO-reference vaccine given at 1/10 of its normal concentration, in an open, randomized, four-arm, multicenter study in Senegal. A total of 1041 healthy Senegalese children aged 8-10 years were screened for participation in this study, of whom 548 had a negative Mantoux test and complied with inclusion and exclusion criteria. These children were randomly allocated a single dose of one of the following vaccines: full-dose Mérieux BCG vaccine (lot E0650); full-dose Mérieux BCG vaccine (lot E0624); full-dose WHO-reference vaccine (Tokyo strain 172); or 1/10 dose WHO-reference vaccine. A follow-up examination, including a tuberculin test, was performed 10-12 weeks after BCG vaccination for 465 (85%) children: 236 Mérieux BCG vaccine (117 lot E0650; 119 lot E0624); 115 full-dose WHO; 114 1/10 dose WHO. The percentage of subjects with a positive tuberculin test after vaccination was significantly lower (P < 0.001) in the 1/10 dose group (81.5%) compared to the other three groups (> 96%). The mean induration diameter was significantly smaller in subjects who received the low-dose of WHO vaccine compared to the others, according to analyses considering all subjects vaccinated, as well as only those subjects with a positive tuberculin test after vaccination. More children in the low-dose group did not have a vaccination scar, and the mean diameter of scars was smaller in this group. The rate of tuberculin reactions, the classification of reactions (Palmer and Edwards), and the characteristics of the vaccinal lesion were similar for the Mérieux BCG vaccines and the full-dose WHO-reference vaccine. All vaccines were safe, as evidenced by the absence of adenitis or suppurative adenitis during the course of the study. Results from this trial show that the two lots of Mérieux BCG vaccine behave equally as well as the full-dose WHO-reference BCG vaccine. The WHO-reference vaccine, given at 1/10 of its normal concentration was significantly less immunogenic, according to all parameters evaluated.     

Bioactivity of autologous irradiated renal cell carcinoma vaccines generated by ex vivo granulocyte-macrophage colony-stimulating factor gene transfer

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced, irradiated tumor vaccines induce potent, T-cell-mediated antitumor immune responses in preclinical models. We report the initial results of a Phase I trial evaluating this strategy for safety and the induction of immune responses in patients with metastatic renal cell carcinoma (RCC). Patients were treated in a randomized, double-blind dose-escalation study with equivalent doses of autologous, irradiated RCC vaccine cells with or without ex vivo human GM-CSF gene transfer. The replication-defective retroviral vector MFG was used for GM-CSF gene transfer. No dose-limiting toxicities were encountered in 16 fully evaluable patients. GM-CSF gene-transduced vaccines were equivalent in toxicity to nontransduced vaccines up to the feasible limits of autologous tumor vaccine yield. No evidence of autoimmune disease was observed. Biopsies of intradermal sites of injection with GM-CSF gene-transduced vaccines contained distinctive macrophage, dendritic cell, eosinophil, neutrophil, and T-cell infiltrates similar to those observed in preclinical models of efficacy. Histological analysis of delayed-type hypersensitivity responses in patients vaccinated with GM-CSF-transduced vaccines demonstrated an intense eosinophil infiltrate that was not observed in patients who received nontransduced vaccines. An objective partial response was observed in a patient treated with GM-CSF gene-transduced vaccine who displayed the largest delayed-type hypersensitivity conversion. No replication-competent retrovirus was detected in vaccinated patients. This Phase I study demonstrated the feasibility, safety, and bioactivity of an autologous GM-CSF gene-transduced tumor vaccine for RCC patients.     

Detection of Salmonella cells within 24 to 26 hours in poultry samples with the polymerase chain reaction BAX system

The parents of 470 students randomly selected from 1321 students attending a state high school were surveyed during the 1993-94 measles epidemic, by means of a take-home questionnaire. The response rate was 87%. Thirty stated that their child had measles during this epidemic; nine of these 30 gave a history of previous vaccination. Overall, 312 of the 470 (76%) stated that their child had been vaccinated, but only 34% indicated that they had vaccination records. There were no measles cases during this epidemic in the group with records. Those not vaccinated were at 10 times increased risk of contracting measles compared to those who had been vaccinated with or without records. Vaccine efficacy estimated in general a decade after vaccination based on parental recall of vaccination status regardless of whether they had vaccination records or not was 91% (95% CI 80%-96%). This calculation excluded 123 who claimed to have had measles prior to 1993 and 30 uncertain of their vaccination status.