Showing papers on "Vaccination published in 1986"
TL;DR: Both antibody loss and the risk of severe disease should be considered when booster-dose strategies for the hepatitis B vaccine are being designed.
Abstract: To study the duration of antibody persistence and protection provided by the hepatitis B vaccine, we followed 773 homosexual men for five years after completion of vaccination. Among the 635 participants in whom antibody levels above 9.9 sample ratio units (SRU) developed after vaccination, 15 percent lost antibody altogether, and in another 27 percent, antibody levels declined below 10 SRU within five years. The extent of the maximal antibody response strongly predicted the persistence of protective antibody. Hepatitis B infection occurred in 55 men; 8 of these infections were clinically important (characterized by the presence of the hepatitis B surface antigen and elevation of liver-enzyme levels), and two of the patients became hepatitis B virus carriers. The long-term risk of hepatitis B infection was inversely related to the maximal antibody response to vaccine. Most severe infections occurred among those who responded poorly or had no response to the vaccination. The risk of late infection with hepatitis B in those with an initially adequate vaccine response increased markedly when antibody levels decreased below 10 SRU, but only 1 of 34 late infections resulted in viremia and liver inflammation. A second series of vaccinations induced a moderate antibody response in 50 percent of the subjects who initially had no response or a poor response; however, the persistence of antibody was poor. Both antibody loss and the risk of severe disease should be considered when booster-dose strategies for the hepatitis B vaccine are being designed.
592 citations
TL;DR: The data suggest that chronically ill patients, who are most susceptible to infection, may have an impaired immune response to the pneumococcal vaccine.
Abstract: We conducted a randomized, double-blind, placebo-controlled trial to test the efficacy of the 14-valent pneumococcal capsular polysaccharide vaccine in 2295 high-risk patients (patients with one or more of the following: age above 55 years and the presence of chronic cardiac, pulmonary, renal, or hepatic disease, alcoholism, or diabetes mellitus). Seventy-one episodes of proved or probable pneumococcal pneumonia or bronchitis occurred among 63 of the patients (27 placebo recipients and 36 vaccine recipients). Vaccine-serotype Streptococcus pneumoniae strains were recovered in association with 11 infections in the placebo group and 14 infections in the vaccine group. Pneumococcal infections occurred most frequently among patients with chronic pulmonary, cardiac, or renal diseases. Among vaccine recipients who subsequently had vaccine-type pneumonia or bronchitis, the majority did not make or sustain serum antibodies against their infecting organism in concentrations that were twice as high as the base-line values, or more than 400 ng of antibody nitrogen per milliliter, although their base-line levels were higher than those in subjects in whom infection did not develop. We were unable to demonstrate any efficacy of the pneumococcal vaccine in preventing pneumonia or bronchitis in this population. Our data suggest that chronically ill patients, who are most susceptible to infection, may have an impaired immune response to the pneumococcal vaccine.
380 citations
TL;DR: The treatment of RSV with Formalin appears to have altered the epitopes of the F or G glycoproteins or both that stimulate neutralizing antibodies, with the result that the immune response consisted largely of "nonfunctional" antibodies.
Abstract: The serum antibody response of infants and children immunized with Formalin-inactivated respiratory syncytial virus (RSV) vaccine 20 years ago was determined by using an enzyme-linked immunosorbent assay specific for the RSV fusion (F) and large (G) glycoproteins and a neutralization assay. Twenty-one young infants (2 to 6 months of age) developed a high titer of antibodies to the F glycoprotein but had a poor response to the G glycoprotein. Fifteen older individuals (7 to 40 months of age) developed titers of F and G antibodies comparable to those in children who were infected with RSV. However, both immunized infants and children developed a lower level of neutralizing antibodies than did individuals of comparable age with natural RSV infections. Thus, the treatment of RSV with Formalin appears to have altered the epitopes of the F or G glycoproteins or both that stimulate neutralizing antibodies, with the result that the immune response consisted largely of "nonfunctional" (i.e., nonneutralizing) antibodies. Subsequent natural infection of the vaccinees with wild-type RSV resulted in enhanced pulmonary disease. Despite this potentiation of illness, the infected vaccinees developed relatively poor G, F, and neutralizing antibody responses. Any or all of three factors may have contributed to the enhancement of disease in the RSV-infected vaccinees. First, nonfunctional antibodies induced by the inactivated RSV vaccine may have participated in a pulmonary Arthus reaction during RSV infection. Second, the poor antibody response of infants to the G glycoprotein present in the Formalin-inactivated vaccine may have been inadequate to provide effective resistance to subsequent wild-type virus infection. Third, the relatively reduced neutralizing antibody response of the infant vaccinees to wild-type RSV infection may have contributed to their enhanced disease by delaying the clearance of virus from their lungs.
293 citations
TL;DR: It is found that the administration of vaccinia virus or a recombinant harbouring the rabies surface antigen gene (VVTGgRAB) is innocuous to foxes, and the recombinant virus can elicit the production of titres of rabies-neutralizing antibodies equal or superior to those obtained with conventional vaccine.
Abstract: Rabies, a viral disease affecting all warm-blooded animals, is prevalent in most parts of the world1, where it propagates amongst wild animals, particularly the fox and dog. The public health and economic consequences of infection in man and livestock are well known. Attempts to control the disease by vaccinating wild carnivores with inactivated or attenuated rabies virus remain controversial, and we have instead evaluated here the potential of a recombinant vaccinia virus to protect foxes against the disease. We have found that the administration of vaccinia virus (VV) or a recombinant harbouring the rabies surface antigen gene (VVTGgRAB) is innocuous to foxes. The recombinant virus can elicit the production of titres of rabies-neutralizing antibodies equal or superior to those obtained with conventional vaccine, and 108 plaque-forming units (PFU) of VVTGIgRAB administered subcutaneously, intradermally or orally confers complete protection to severe challenge infection with street rabies virus.
245 citations
TL;DR: The overall efficacy of pneumococcal vaccine was estimated at 64% (95% confidence limits, 47% to 76%); efficacy did not differ significantly with age.
Abstract: The efficacy of pneumococcal vaccine in groups of patients in the United States at high risk for pneumococcal disease was estimated by comparing distributions of serotypes of Streptococcus pneumoniae isolated from vaccinated and unvaccinated persons. Between May 1978 and March 1984, 187 blood isolates and 62 cerebrospinal fluid isolates from vaccinated patients, and 1447 blood isolates and 191 cerebrospinal fluid isolates from unvaccinated patients were serotyped at the Centers for Disease Control. The study did not include patients who were less than 2 years old or who had Hodgkin's disease, multiple myeloma, or immunoglobulin deficiency. In patients with bacteremic disease, the overall efficacy of pneumococcal vaccine was estimated at 64% (95% confidence limits, 47% to 76%); efficacy did not differ significantly with age. In persons over 65 years of age with diabetes mellitus, chronic heart disease, pulmonary disease, or no underlying illnesses, efficacy was 61% (95% confidence limits, 1% to 85%). These findings support the use of pneumococcal vaccine in selected populations in the United States.
237 citations
TL;DR: Vaccination of normal 15-month-old children with a safe and effective vaccine with long-lasting immunity could reduce the cost by 66% and result in a savings of $7 for every dollar spent on the vaccination program.
Abstract: Varicella (chickenpox) has long been considered a benign, inevitable disease of childhood. Complications are generally mild and rarely severe, and virtually every individual is infected by adulthood. Infection is associated, however, with a high risk of serious complications in certain high-risk groups, such as leukemic children. Concerns about the severity of varicella in this population have led to the development and testing of a live, attenuated vaccine. Because of the favorable results thus far available, the vaccine may soon be licensed for use in high-risk individuals. The fact that a vaccine may soon be available has led to an increased interest in the potential benefits of a childhood varicella vaccine program. The costs associated with varicella infection in normal persons without a varicella vaccination program have been estimated to be approximately $400 million, 95% of which is the cost of caring for a child at home. Vaccination of normal 15-month-old children with a safe and effective vaccine with long-lasting immunity could reduce the cost by 66% and result in a savings of $7 for every dollar spent on the vaccination program. This assumes that vaccine would be administered only once with measles, mumps, and rubella vaccine, that there would be no increase in the number of varicella cases in older persons who are at increased risk for complications, and that there would be no deleterious effect on the occurrence and severity of herpes zoster.(ABSTRACT TRUNCATED AT 250 WORDS)
236 citations
TL;DR: This work demonstrates the feasibility of a recombinant virus vaccine containing the rabies glycoprotein gene for immunization of raccoons, and possibly other wildlife, to obtain long-term protection against rabies.
Abstract: Animal rabies control has been frustrated by the existence of multiple wildlife reservoirs and the lack of efficacious oral vaccines. In this investigation, raccoons fed a vaccinia-rabies glycoprotein recombinant virus in a sponge bait developed rabies virus-neutralizing antibody (0.6-54.0 units) and resisted street rabies virus infection 28 and 205 days after feeding. Additional raccoons immunized by oral infusion with attenuated antigenic variants of rabies virus strains CVS-11 and ERA failed to develop rabies virus-neutralizing antibody. This work demonstrates the feasibility of a recombinant virus vaccine containing the rabies glycoprotein gene for immunization of raccoons, and possibly other wildlife, to obtain long-term protection against rabies.
231 citations
TL;DR: The finding that live virus vaccine induced relatively long-lasting antibody in both local and serum compartments suggested that this vaccine may be a suitable alternative to inactivated vaccine for use in healthy persons.
Abstract: An enzyme-linked immunosorbent assay was used to measure nasal-wash and serum isotype-specific hemagglutinin antibody responses in 109 seronegative (hemagglutination-inhibiting titer less than or equal to 1:8) adults vaccinated intranasally with live attenuated A/Washington/897/80 (H3N2) or A/California/10/78 (H1N1) cold-adapted (ca) virus or with licensed subvirion vaccine subcutaneously Live and inactivated virus elicited serum immunoglobulin A (IgA) responses in 83 and 96% of vaccinees, respectively, and elicited serum IgG responses in 72 and 100% of vaccinees Inactivated virus induced higher titers of serum antibodies than did live virus and stimulated a nasal-wash IgG response more often than did live virus (94 versus 59%, P less than 001) In contrast, only 38% of inactivated virus vaccinees had local IgA responses compared with 83% of live virus vaccinees Serum IgA and IgG and nasal IgG antibody titers remained elevated above prevaccination levels for at least 6 months in most of the live and inactivated vaccine responders, but the mean level of local IgA antibody induced by infection with live virus vaccine, in particular, decreased substantially Considered in the context of previous work, the finding that live virus vaccine induced relatively long-lasting antibody in both local and serum compartments suggested that this vaccine may be a suitable alternative to inactivated vaccine for use in healthy persons
217 citations
TL;DR: It is concluded that antibodies to toxin components may not be sufficient to provide protection against all strains of B. anthracis and that other antigens may play a role in active immunity and that the efficacy of anthrax vaccines must be tested by using vaccine-resistant isolates ifprotection against all possible challenge strains is to be assured.
Abstract: Several strains of Bacillus anthracis have been reported previously to cause fatal infection in immunized guinea pigs. In this study, guinea pigs were immunized with either a protective antigen vaccine or a live Sterne strain spore vaccine, then challenged with virulent B. anthracis strains isolated from various host species from the United States and foreign sources. Confirmation of previously reported studies (which used only protective antigen vaccines) was made with the identification of 9 of the 27 challenge isolates as being vaccine resistant. However, guinea pigs immunized with the live Sterne strain spore vaccine were fully protected against these nine isolates. In experiments designed to determine the basis of vaccine resistance, guinea pigs which were immunized with individual toxin components and which demonstrated enzyme-linked immunosorbent assay antibody titers comparable to those induced by Sterne strain vaccine were not protected when challenged with a vaccine-resistant isolate. We concluded that antibodies to toxin components may not be sufficient to provide protection against all strains of B. anthracis and that other antigens may play a role in active immunity. As a practical matter, it follows that the efficacy of anthrax vaccines must be tested by using vaccine-resistant isolates if protection against all possible challenge strains is to be assured.
214 citations
TL;DR: Poor responders to vaccine may benefit from revaccination, and genetic factors may modulate the immune response to vaccination.
Abstract: Twenty-eight health care workers who had a poor antibody response when initially vaccinated with hepatitis B vaccine were revaccinated with three additional 20-microgram doses. Eight of the twenty nonresponders, who had levels of antibody to hepatitis B surface antigen (anti-HBs) of less than 8 estimated radioimmunoassay (RIA) units, and all 8 of the hyporesponders, who had anti-HBs levels of 8 or 16 RIA units, attained anti-HBs levels of 36 RIA units or more after revaccination. Tests for HLA-A, B, C, and DR; for complement proteins C2, C4A, C4B, and BF; and for the erythrocyte enzyme glyoxalase I were done in 17 nonresponders and 3 hyporesponders. Nine (45%) had HLA-DR7 and 8 (40%) had HLA-DR3, compared with an expected rate of 23% in the general population. At least one of two extended haplotypes (B44, DR7, FC31 or B8, DR3, SCO1) were detected in 6 of the 9 who did not respond to revaccination, compared with 2 of 11 who responded to a second course of vaccine. Poor responders to vaccine may benefit from revaccination, and genetic factors may modulate the immune response to vaccination.
203 citations
TL;DR: Prechallenge nasal IgA, detected almost exclusively in subjects naturally infected or vaccinated with live ca virus, was associated with protection and inactivated vaccine failed to produce significant local IgA during the primary response, but seemed to prime for secondary local antibody responses after challenge with liveca virus.
Abstract: Live attenuated, cold-adapted (ca) influenza A vaccines administered intranasally have been well characterized as safe and immunogenic, but comparative data on protective efficacy are required for further development. In this study, 59 young children were divided into the following four groups based on prior exposure to influenza A (H3N2) virus: natural infection, live ca vaccine given intranasally, inactivated vaccine given im, and no previous exposure. Virus challenge with homologous live ca vaccine occurred 12 months after vaccination or natural infection. Prior natural infection and live ca vaccine significantly reduced ca virus shedding after challenge compared with inactivated vaccine or no prior exposure to influenza A virus. Prechallenge nasal IgA, detected almost exclusively in subjects naturally infected or vaccinated with live ca virus, was associated with protection. Although inactivated vaccine failed to produce significant local IgA during the primary response, it seemed to prime for secondary local antibody responses after challenge with live ca virus.
TL;DR: Clinical trials designed to obtain information on minimum dose immunogenicity pre- and postexposure prophylaxis, immunization of various age groups, and booster immunizations for seropositive individuals documented a 94% to 100% seroconversion rate and persistence of antibodies at 3 to 4 years.
Abstract: Immunization of normal children and adults with Oka strain live varicella vaccine from several manufacturers has been studied in our laboratory and elsewhere. This paper summarizes clinical trials designed to obtain information on minimum dose immunogenicity pre- and postexposure prophylaxis, immunization of various age groups, and booster immunizations for seropositive individuals. These studies documented a 94% to 100% seroconversion rate with 95% to 100% persistence of antibodies at 3 to 4 years. Protective efficacy was more than 90%, and the vaccine was successful in preventing varicella when a high dose was given postexposure. Clinical reactions were limited to temperature elevations and minor papulovesicular rashes that occurred in 5% to 10% of vaccinees. Herpes zoster has been absent in vaccinated healthy individuals.
TL;DR: The ELISA system was shown to be capable of detecting anti-PA and anti-LF antibodies in the sera of individuals with histories of clinical anthrax, and was markedly superior in terms of reproducibility, reliability, specificity, and simplicity in performance and stability of the bound antigen.
Abstract: A competitive inhibition enzyme-linked immunosorbent assay (ELISA) was developed to detect antibodies in serum to the protective antigen (PA) and lethal factor (LF) components of anthrax toxin. Current human vaccination schedules with an acellular vaccine induce predictable and lasting antibody titers to PA and, when present in the vaccine, to LF. Live spore vaccine administered to guinea pigs in a single dose conferred significantly better protection than the human vaccines (P less than 0.001), although they elicited significantly lower (P less than 0.0005) anti-PA and anti-LF titers at time of challenge with virulent Bacillus anthracis. Substantial anti-PA and anti-LF titers may not, therefore, indicate solid protective immunity against anthrax infection. The ELISA system was also shown to be capable of detecting anti-PA and anti-LF antibodies in the sera of individuals with histories of clinical anthrax. The advantage of ELISA over the Ouchterlony gel diffusion test and indirect microhemagglutination assay are demonstrated. There was a highly significant degree of correlation between ELISA and the indirect microhemagglutination assay (P less than 0.0005); but ELISA was markedly superior in terms of reproducibility, reliability, specificity, and simplicity in performance and stability of the bound antigen.
TL;DR: It is suggested that alternative strategies are needed to maximize the protective effect of pneumococcal vaccine in the population at greatest risk, as in vitro studies did not support the concept that a certain level of antibody was specifically associated with the capacity to opsonize pneumococci.
Abstract: To investigate the protective effects of pneumococcal vaccine, we assayed serum from healthy adults and from elderly bronchitics for antibody and opsonic activity against nine serotypes of S. pneumoniae. Before vaccination, there was no relation between opsonization and the level of antibody measured by RIA. Some serotypes were well opsonized in the absence of detectable antibody to capsular polysaccharide; others were not, despite modest levels of antibody. These in vitro studies did not support the concept that a certain level of antibody (e.g., >.250 ng of antibody nitrogen/ml) was specifically associated with the capacity to opsonize pneumococci. Nearly all postvaccination sera had increased antibody and opsonic activity against all serotypes, but the lack of correlation in any individual serum persisted. RIA showed that pre- and postvaccination levels of antibody in elderly adults with chronic lung disease were similar to those of younger adults. In elderly bronchitics, opsonizing activity for six of the nine serotypes was lower after vaccination, a result suggesting a possible explanation for the failure of pneumococcal vaccine to be fully protective in these subjects. Elderly subjects had higher levels of antibody to phosphocholine, but when isolated, this antibody did not opsonize any of the vaccine strains of pneumococci. These results suggest that alternative strategies are needed to maximize the protective effect of pneumococcal vaccine in the population at greatest risk.
TL;DR: The vast majority of adverse reactions following immunisation of children with live measles-mumps-rubella (MMR) vaccine were shown in a double-blind, placebo-controlled, cross-over study in 581 twin pairs to be only temporally but not causally related to the vaccination.
TL;DR: The Merck, Sharp and Dohme hepatitis B vaccine formulated from HBsAg produced by a recombinant strain of Saccharomyces cerevisiae has proven to be highly immunogenic and safe.
TL;DR: Impaired herd immunity to the epidemic strain of poliovirus type 3, which differed from the type 3 vaccine strains in both immunological and molecular properties, was important in the emergence of this outbreak.
TL;DR: In three double-blind placebo-controlled trials of pneumococcal capsular polysaccharide vaccines against death from acute lower-respiratory-tract infections (ALRI), children were vaccinated at 6 months to 5 years of age.
TL;DR: The antibody levels to most pneumococcal types decreased rapidly after both injections of the vaccine and the generally poor immunogen types 6A and 23F elicited a weak antibody response mainly in the immunoglobulin M class.
TL;DR: A booster dose of hepatitis B vaccine was given to 143 children in whom hepatitis B had not developed 1 year after initial vaccination and the protective efficacy of the vaccine was 100%, but during the 5th and 6th years it fell to 67%.
TL;DR: Current levels of vaccination appear too low considering the potential health benefits and cost-effectiveness, and the low estimates of 10% of pneumonia as pneumococcal and a 3-year duration of immunity now appear more likely.
Abstract: We updated a 1978 cost-effectiveness analysis of vaccination against pneumococcal pneumonia in light of the introduction in 1983 of a 23-valent vaccine, recent medical literature, and different relative prices of medical services. Although other base-case assumptions have remained reasonable, the low estimates of 10% of pneumonia as pneumococcal and a 3-year duration of immunity now appear more likely. Vaccination of a person age 65 or older could gain a year of healthy life for about $6000 in 1983 dollars. Medicare has covered pneumococcal vaccination since 1981. With the revised assumptions, net Medicare expenditures ranged from about $5.50 to $10.50 per vaccination, or from $4400 to $8300 per year of healthy life gained. Vaccination of an elderly person would almost break even, if duration of immunity were 8 years and would be cost saving if the vaccine were administered under a public program. Current levels of vaccination appear too low considering the potential health benefits and cost-effectiveness.
TL;DR: Despite comparable renal allograft function, cyclosporine-treated patients had a significantly lower immune response against influenza A viruses than azathioprinetreated patients, and booster immunization proved valuable in this group.
Abstract: Influenza vaccination has been strongly recommended for immunosuppressed renal transplant recipients. However, immunosuppression may lead to impaired antibody responses. We studied the antibody response to an inactivated trivalent influenza vaccine in 59 renal transplant recipients with life-sustaining kidney function: 21 were on cyclosporine and prednisone, 38 on azathioprine and prednisone. Healthy volunteers (n = 29) and patients on hemodialysis (n = 28) served as controls. Despite comparable renal allograft function, cyclosporine-treated patients had a significantly lower immune response against influenza A viruses than azathioprine-treated patients, whether mean antibody levels, fourfold titer rise, or seroconversion to protective titers was analyzed. No significant differences in antibody responses were found between healthy controls and patients on azathioprine. The patients on hemodialysis showed an impaired response to vaccination. However, in contrast to the cyclosporine-treated patients, booster immunization proved valuable in this group.
Journal Article•
TL;DR: The findings indicate that recent influenza epidemics caused only modest excess ARD morbidity among pregnant women, and significant excess occurred only in association with antigenic shift, and support current national policy recommendations with respect to influenza vaccination of pregnant women.
Abstract: The medical literature contains little information on the occurrence of excess morbidity among pregnant women during recent influenza epidemics Rates of medical visits for acute respiratory disease (ARD) among pregnant and nonpregnant members of a large prepaid practice population were examined Use of medical services for ARD was ascertained for approximately 1,000 pregnant women and 3,000 nonpregnant women during each of four epidemic periods (1975, 1976, 1978, 1979) and a nonepidemic period (1977) Comparing the combined epidemic periods with the nonepidemic period, there were significant excesses of 237 (standard error (SE) = 81) ARD contacts per 1,000 attributable to epidemic influenza for pregnant women and 102 (SE = 34) for nonpregnant women ARD hospitalization rates among pregnant women were low (2 per 1,000), and there were no maternal deaths The significant ARD excess among pregnant women was concentrated in the 1978 period with reappearance of the A/Russia H1N1 subtype in the community and was confined to those under age 25 who would not have ben previously exposed to this subtype (944 (SE = 285] These findings indicate that recent influenza epidemics caused only modest excess ARD morbidity among pregnant women, and significant excess occurred only in association with antigenic shift These findings support current national policy recommendations with respect to influenza vaccination of pregnant women
Journal Article•
TL;DR: The vaccine was well tolerated and immunogenic, and was associated with a significant decrease in the attack rate of chickenpox following an intimate exposure to varicella-zoster virus, conferring about 80% protection in leukemic children.
Abstract: Live attenuated varicella vaccine has been administered to 307 children with leukemia in remission and to 86 healthy adults. The vaccine was well tolerated and immunogenic. The major side effect in leukemic children receiving maintenance chemotherapy was development of a vaccine-associated rash. Vaccinees in whom a rash developed were potentially somewhat infectious to others about 1 month after immunization. Vaccination was not associated with an increase in the incidence of herpes zoster or in relapse of leukemia. Vaccination provided excellent protection against severe varicella. It was associated with a significant decrease in the attack rate of chickenpox following an intimate exposure to varicella-zoster virus, conferring about 80% protection in leukemic children. The cases of breakthrough varicella that occurred were mild. Thus, the vaccine may either prevent or modify varicella in high-risk individuals. It may also have use for prevention of nosocomial varicella.
TL;DR: It is indicated that chloroquine taken in the dose recommended for malaria prophylaxis can reduce the antibody response to primary immunization with intradermal human diploid-cell rabies vaccine.
Abstract: We conducted a randomized controlled trial to evaluate the antibody response of freshman veterinary students to intradermal human diploid-cell rabies vaccine administered concurrently with chloroquine, a drug frequently used for chemoprophylaxis against malaria. Fifty-one students who had not been vaccinated against rabies were enrolled: 26 received 300 mg of chloroquine base per week (the recommended dose for malaria prophylaxis); 25 did not receive chloroquine and served as controls. All subjects received 0.1 ml of rabies vaccine intradermally on days 0, 7, and 28. Chloroquine was administered weekly to the treatment group, beginning nine days before the first dose of vaccine and continuing until day 48. The mean rabies-neutralizing antibody titer for the chloroquine group was significantly lower than that for the control group on each day of testing — i.e., day 28 (P = 0.0094), day 49 (P = 0.0008), and day 105 (P = 0.0002) — although both groups had neutralizing antibody titers on days 49 and ...
TL;DR: It is concluded that in young children the RRV-1 (rhesus monkey) rotavirus vaccine is more immunogenic than the RIT 4237 (bovine) rotvirus vaccine, but vaccination with RRv-1 is associated with significant adverse reactions.
Abstract: Heterologous live, oral rotavirus vaccines of rhesus monkey (RRV-1) and bovine (RIT 4237) origin were tested for immunogenicity, excretion of virus, and clinical reactions in six- to eight-month-old infants. Antibody response, indicating infection with the vaccine virus, was detected in 21 (88%) of 24 children receiving the RRV-1 vaccine and in 18 (75%) of 24 receiving the RIT 4237 vaccine. Excretion of virus in the stools within one week after vaccination was demonstrable in 84% of the RRV-1 and in 21% of the RIT 4237 vaccinees. RRV-1 vaccination was associated with a febrile response (over 38 C) that clustered on days 3 or 4 postvaccination in 64% of the recipient children. In addition, 20% of the RRV-1 vaccinees had watery stools on days 4 or 5. Fever on days 3 and 4 and loose stools were not seen in the RIT 4237 vaccinees. We concluded that in young children the RRV-1 (rhesus monkey) rotavirus vaccine is more immunogenic than the RIT 4237 (bovine) rotavirus vaccine, but vaccination with RRV-1 is associated with significant adverse reactions. © 1986 by The University of Chicago. All rights reserved.
TL;DR: The principal conclusion of the analyses is that benefit is to be gained in the UK by the introduction of a multiple-stage vaccination policy involving high levels of vaccination coverage of young male and female children and teenage girls, plus continued surveillance and vaccination of adult women in the child-bearing age classes.
Abstract: The paper examines predictions of the impact of various one-, two- and three-stage vaccination policies on the incidence of congenital rubella syndrome (CRS) in the United Kingdom with the aid of a mathematical model of the transmission dynamics of rubella virus. Parameter estimates for the model are derived from either serological data or case notifications, and special attention is given to the significance of age-related changes in the rate of exposure to rubella infection and heterogeneous mixing between age groups. Where possible, model predictions are compared with observed epidemiological trends. The principal conclusion of the analyses is that benefit is to be gained in the UK, both in the short and long term, by the introduction of a multiple-stage vaccination policy involving high levels of vaccination coverage of young male and female children (at around two years of age) and teenage girls (between the ages of 10-15 years), plus continued surveillance and vaccination of adult women in the child-bearing age classes. Model predictions suggest that to reduce the incidence of CRS in future years, below the level generated by a continuation of the current UK policy (the vaccination of teenage girls), would require high rates of vaccination (greater than 60%) of both boys and girls at around two years of age. Numerical studies also suggest that uniform vaccination coverage levels of greater than 80-85% of young male and female children could, in the long term (40 years or more), eradicate rubella virus from the population. The robustness of these conclusions with respect to the accuracy of parameter estimates and various assumptions concerning the pattern of age-related change in exposure to infections and 'who acquires infection from whom' is discussed.
TL;DR: A highly efficacious, inactivated hepatitis A vaccine can be produced from virus grown in cell culture, and all marmosets with any detectable antibody to HAV, as a result of vaccination, were protected against virulent infection on challenge with HAV.
Abstract: Hepatitis A virus (HAV) strain CR326, adapted to grow in LLC-MK2 cells, was highly purified, inactivated with formalin, adsorbed to alum, and tested for capacity to induce antibody to HAV in both mice and marmosets. The minimum dose of HAV antigen necessary to produce antibody in 50% of mice was 10 ng. As little as three doses of 1 ng each produced antibody in 50% of marmosets. Further, all marmosets with any detectable antibody to HAV, as a result of vaccination, were protected against virulent infection on challenge with HAV. Thus a highly efficacious, inactivated hepatitis A vaccine can be produced from virus grown in cell culture. Although LLC-MK2 cells are unacceptable for use in human vaccine preparation, HAV can also be prepared in a similar manner in MRC-5 cells, which are acceptable for human vaccine manufacture.
TL;DR: Selective early vaccination of children of young mothers who have low antibody titers would eliminate an important focus of measles susceptibility.
TL;DR: Both severity of infection and development of measles in vaccinated children were related to intensity of exposure and there was significantly greater vaccination coverage among younger siblings of vaccinated children who had contracted measles than among other children in the community.
Abstract: We studied the occurrence of measles in vaccinated children from an urban area of Guinea-Bissau where measles causes high mortality. Vaccinated children who developed measles required more-intense exposure to become infected (they had a higher ratio of secondary cases [infected in the house] to index cases [infected outside the house]), had a lower mortality among secondary cases, and were less infectious (they generated fewer secondary cases than did unvaccinated children with measles). The attack rate among vaccinated children was significantly higher in households in which someone died of measles. Both severity of infection and development of measles in vaccinated children were related to intensity of exposure. Vaccine efficacy was 72%, and 33% of cases occurred among vaccinated children; however, most mothers remained confident that vaccinated children get milder measles. Moreover, there was significantly greater vaccination coverage among younger siblings of vaccinated children who had contracted measles than among other children in the community.