Biomedical subjects

D I Bernstein

Publications and source records attributed to D I Bernstein.

At least 91 records · Page 5Linked to original sources

PubMed1996

DNA immunization against experimental genital herpes simplex virus infection.

A nucleic acid vaccine, expressing the gene encoding herpes simplex virus (HSV) type 2 glycoprotein D (gD2) under control of the cytomegalovirus immediate-early gene promoter, was used to immunize guinea pigs against genital HSV-2 infection. The vaccine elicited humoral immune responses comparable to those seen after HSV-2 infection. Immunized animals exhibited protection from primary genital HSV-2 disease with little or no development of vesicular skin lesions and significantly reduced HSV-2 replication in the genital tract. After recovery from primary infection, immunized guinea pigs experienced significantly fewer recurrences and had significantly less HSV-2 genomic DNA detected in the sacral dorsal root ganglia compared with control animals. Thus, immunization reduced the burden of latent infection resulting from intravaginal HSV-2 challenge, and a nucleic acid vaccine expressing the HSV-2 gD2 antigen protected guinea pigs against genital herpes, limiting primary infection and reducing the magnitude of latent infection and the frequency of recurrent disease.

Animals↗

PubMed1996

Speed of onset of action of Tilarin.

Two studies have been carried out specifically to examine the speed of onset of action of intranasal nedocromil sodium 1% (Tilarin) for the relief of symptoms due to ragweed allergic rhinitis. One, a multicentre placebo-controlled comparative study using a QID regimen, 1 spray per nostril, was designed to assess the speed of onset of action of nedocromil sodium during the first week of treatment in patients with rhinitis symptoms, and to evaluate the efficacy and safety of nedocromil sodium during 6 weeks of treatment (1). A 1-week baseline, the start of which was timed to coincide with the start of the ragweed season, was followed by 6 weeks double-blind trial treatment; only patients (n = 166) who were symptomatic at the end of baseline were included in the double-blind phase. Non-parametric analyses of all variables including a summary score (stuffy nose, runny nose, itchy nose and sneezing) showed that the onset of action of nedocromil sodium occurred on the first day of treatment. Further, patients using nedocromil sodium had less symptoms during the 10 days of peak pollen, at which time physician assessment showed reduced mucosal oedema and nasal discharge, and both patient and clinician opinions favoured nedocromil sodium. No significant adverse events were reported during this 6-week study. In the second study (2), 104 patients were randomly allocated to receive either nedocromil sodium or placebo, QID. They then spent 10 hours per day for 2 consecutive days in Iowa City Park during the peak of the ragweed season. Only patients showing significant symptoms of seasonal allergic rhinitis (SAR) during 3 hourly baseline assessments were included. Over the 2-day period, symptom scores for stuffy nose, runny nose, itchy nose and sneezing, and global symptom summary scores, were recorded at 19 hourly time points. At home in the evening, patients recorded symptom scores for the post-exposure period. In comparison with placebo, nedocromil sodium significantly improved rhinitis symptoms within 2 hours, and this reduction in SAR symptoms was maintained throughout the 2-day exposure period. Post exposure symptom summary scores were also significantly lower in patients treated with nedocromil sodium than in those patients treated with placebo. Overall, very few adverse events were reported, none of them serious. In conclusion, nedocromil sodium 1% nasal spray acts rapidly, within 2 hours on the first day of treatment, to reduce ongoing symptoms of SAR. Relief of rhinitis symptoms is maintained throughout the peak pollen period with nedocromil sodium QID, which appears to be a safe and well tolerated treatment for ragweed SAR.

Adolescent↗

PubMed1996

Safety and efficacy of high-dose rhesus-human reassortant rotavirus vaccines--report of the National Multicenter Trial. United States Rotavirus Vaccine Efficacy Group.

OBJECTIVE: Rotavirus is a leading cause of morbidity and mortality from dehydrating gastroenteritis in infants and young children worldwide. Virtually every child is infected by age 4 years, justifying universal childhood immunization when a safe and effective vaccine is available. We report the results of a multicenter, placebo-controlled field trial in the United States of monovalent serotype 1 and tetravalent (TV) rhesus-human reassortant rotavirus vaccines (RRVs). DESIGN: In this randomized, double-blind trial, 1278 healthy infants ages 5 to 25 weeks received three oral doses of RRV serotype 1, RRV-TV, or a placebo at approximately 2, 4, and 6 months of age. Vaccines contained 4 x 10(5) plaque-forming units of virus. Gastroenteritis episodes were monitored, and severity was graded throughout one rotavirus season. Two stool specimens per episode were tested for rotavirus. RESULTS: The incidence of reactions did not differ among treatment groups during the 5-day, postvaccination safety surveillance period for any of the three doses. Both vaccines significantly reduced the incidence of rotavirus gastroenteritis. Vaccination was most protective against serious rotavirus illness; RRV-TV prevented 49% of rotavirus episodes, 80% of very severe episodes, and 100% of dehydrating rotavirus illness. Reduction of rotavirus disease by RRV-TV resulted in significantly fewer total episodes of gastroenteritis of all causes and an 82% reduction in all cases of dehydrating diarrhea. CONCLUSION: RRV-TV is highly protective against very severe, dehydrating rotavirus gastroenteritis.

Administration, Oral↗

PubMed1995

Analysis of herpes simplex virus-specific T cells in the murine female genital tract following genital infection with herpes simplex virus type 2.

A murine model of genital infection with a thymidine kinase-deficient (tk-) strain of herpes simplex virus type 2 (HSV-2) was utilized to examine the development of the local T cell response in the genital mucosa and draining genital lymph nodes (gLN). HSV-specific cytokine-secreting T cells were detected in the gLN 4 days postintravaginal inoculation but not in the urogenital tract or spleen until 5 days postinoculation, suggesting the cellular immune response originates in the gLN. More CD4+ than CD8+ gLN T cells were detected by flow cytometric analysis following primary vaginal inoculation and the majority of HSV-specific gLN T cells detected by ELISPOT were CD4+ and Th1-like based on secretion of IFN gamma and not IL-4 or IL-5. A similar population of HSV-specific memory T cells persisted in the genital tract 2 months following HSV-2 tk- genital inoculation. These data suggest that the urogenital cellular immune response elicited in mice following genital inoculation with HSV-2 tk- is predominantly CD4+ and Th1-like, resembling that observed in humans. The results of this study are important for the rational design of vaccines capable of inducing protective immunity in the genital tract.

Animals↗

PubMed1995

Evaluation of rhesus rotavirus monovalent and tetravalent reassortant vaccines in US children. US Rotavirus Vaccine Efficacy Group.

OBJECTIVE: To determine the safety and relative efficacy of two reassortant rhesus rotavirus vaccines over two rotavirus seasons. DESIGN: A prospective, double-masked, placebo-controlled trial. SETTING: Twenty-three centers in the United States. PARTICIPANTS: A total of 1006 healthy infants between 4 and 26 weeks of age were enrolled, and 898 received three doses of vaccine or placebo. MAIN OUTCOME MEASURES: Reactogenicity was determined by comparing the incidence of fever, diarrhea, and/or vomiting for 5 days after each dose of vaccine. Rotavirus IgA and neutralizing antibody to rhesus rotavirus and four rotavirus serotypes were measured in a subset of subjects. Relative efficacy was determined by comparing the incidence of rotavirus gastroenteritis after three doses of vaccine or placebo over two rotavirus seasons. RESULTS: Adverse reactions were mild and limited to a small but significant increase in the incidence of fever after the first dose of tetravalent but not monovalent vaccine. The relative efficacy against rotavirus disease over the 2 years of observation was 40% (98.3% confidence interval, 7% to 62%) for the monovalent and 57% (98.3% confidence interval, 29% to 74%) for the tetravalent vaccine. In post hoc analyses, the relative efficacy against very severe rotavirus gastroenteritis was 73% and 82% for monovalent and tetravalent vaccine recipients, respectively. Also, a 67% and 78% reduction in medical visits for rotavirus gastroenteritis was observed. Both vaccines protected against disease caused by serotype 1 rotavirus, but only the tetravalent vaccine reduced the incidence of disease caused by non-serotype 1 rotavirus infection detected in the second season. It is unclear, however, whether this result represents serotype-specific protection or a difference in the duration of protection. CONCLUSIONS: Vaccination with both vaccines was safe and significantly reduced the incidence of rotavirus gastroenteritis, but only the tetravalent vaccine provided protection against disease caused by non-serotype 1 rotaviruses during the second year of follow-up.

Antibodies, Viral↗

PubMed1995

Generation of humoral immune responses against herpes simplex virus type 2 in the murine female genital tract.

A murine model of genital infection with a thymidine kinase-deficient (tk-) strain of herpes simplex virus type 2 (HSV-2) was utilized to examine the local urogenital antibody response to HSV-2. Vaginal inoculation with HSV-2 tk- protected against a subsequent genital challenge with a lethal dose of virulent HSV-2. After primary vaginal infection, predominantly HSV-specific IgG antibodies were detected in serum and vaginal secretions. HSV-specific IgG antibody-secreting cells (ASC) were detected first and in greatest numbers in the genital lymph nodes (gLN) after primary HSV-2 tk- inoculation. HSV-specific IgG or IgA ASC were not detected in the urogenital mucosa after primary HSV-2 vaginal infection. Vaginal HSV-2 challenge of HSV-immune mice resulted in increased HSV-specific serum IgG antibody and vaginal IgA antibody titers. HSV-specific IgG ASC were detected by 4 days postchallenge in gLN and by Days 6 and 7 postchallenge in the spleen and genital mucosa. These results suggest that urogenital humoral responses originate in the gLN following HSV genital infection and that gLN may serve as the primary source of the HSV-specific IgG- and IgA-secreting cells present in the urogenital mucosa after vaginal challenge.

Animals↗

PubMed1995

Lack of correlation between serum rotavirus antibody titers and protection following vaccination with reassortant RRV vaccines. US Rotavirus Vaccine Efficacy Group.

In a large placebo-controlled efficacy trial of the rhesus tetravalent (RRV-TV) and serotype 1 monovalent (RRV-S1) rotavirus vaccines in multiple sites throughout the United States, protection against rotavirus disease over a 2-year period was found to be 57 and 40%, respectively (Bernstein et al., J. Am. Med. Assoc., 1995, 273, 1191-1196). Sera collected from a subset of subjects during this trial were used to determine possible correlations between rotavirus antibody responses after vaccination and protection. Between 82% (RRV-S1) and 92% (RRV-TV) of the vaccinees seroconverted by at least one of the six antibody assays performed (i.e. rotavirus IgA and neutralizing antibody to RRV and serotype 1-4 human rotaviruses). Rises in neutralizing antibody were due primarily to RRV. The seroconversion rate was only 18-22% to each of the four human rotavirus serotypes following RRV-TV vaccination and was only 43% to serotype 1 human rotavirus after RRV-S1 administration. Furthermore, no correlate of immunity against rotavirus infection or disease was identifiable based on seroconversion to any of the antibodies measured. Likewise, no consistent relationship was found between the titers of any of these six antibodies following vaccination and protection against rotavirus, thus suggesting that serum antibody titers will not be useful markers of protection with these reassortant RRV vaccines. In addition, vaccinated subjects did not develop higher titers of neutralizing antibody to human rotaviruses following a subsequent natural rotavirus illness, a further indication that only weak immune responses to human rotaviruses were stimulated by vaccination with the RRV reassortants.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Viral↗

PubMed1995

Reactogenicity and immunogenicity of a three-component acellular pertussis vaccine administered as the primary series to 2, 4 and 6 month old infants in the United States.

Five hundred and fifty-seven infants received either an acellular pertussis (DTaP) vaccine containing pertussis toxoid (PT), filamentous hemagglutinin (FHA) and pertactin (PRN) or one of two commercially available whole-cell pertussis (DTP) vaccines at 2, 4 and 6 months. One month after the third immunization, IgG antibody values to pertussis toxoid, filamentous hemagglutinin and PRN were significantly greater following DTaP than either DTP (P < 0.05). When reactions within 48 h after all three doses of vaccine were combined, fever 101 degrees, > or = moderate fussiness, > or = moderate pain, swelling 10 mm, and erythema 10 mm occurred less often after DTaP compared with DTP-Connaught (P < 0.001). The same adverse events were also less after DTaP compared with DTP-Lederle (P < 0.05), except for erythema 10 mm. This three-component DTaP vaccine produced fewer adverse events and greater antibody values to PT, FHA and PRN in comparison with either licensed DTP vaccine when given as the primary series.

Adhesins, Bacterial↗

PubMed1995

Effect of imiquimod as an adjuvant for immunotherapy of genital HSV in guinea-pigs.

Imiquimod, an immunomodulator which upregulates cell-mediated immune responses, was evaluated as an adjuvant for immunotherapy of recurrent genital herpes simplex virus (HSV) infection in guinea-pigs. In two experiments at separate research centres, animals were immunized with HSV glycoprotein and either placebo, 1 or 5 days of imiquimod, or complete Freund's adjuvant, 14 and 35 days after genital HSV-2 infection. Recurrent lesion days were then evaluated from days 15-91. In both experiments, immunization with glycoprotein and imiquimod most effectively reduced recurrence compared with unimmunized controls (53-69%, p < 0.001-0.05). A peak reduction of 70-80% was observed following the second immunization. This reduction was greater than that provided by immunization with glycoprotein and complete Freund's adjuvant in these experiments or those previously reported.

Adjuvants, Immunologic↗

PubMed1995

A self-management program for adult asthma. Part II: Cost-benefit analysis.

BACKGROUND: We performed a cost-benefit analysis of a previously described self-management program for adult asthma. METHODS: Direct and indirect cost data from 47 subjects who participated in the self-management program were analyzed. In particular, costs incurred by the subjects 1 year before participation were compared with costs incurred 1 year after participation. RESULTS: The cost-benefit analysis indicated that the program was beneficial, reducing the cost of asthma to each patient by $475.29. The benefit came primarily from reductions in hospital admissions (reduced from $18,488 to $1538) and income lost as a result of asthma (reduced from $11,593 to $4589). The asthma self-management program cost $208.33 per patient. Comparison of the program cost with the program benefit produced a 1:2.28 cost-benefit ratio, demonstrating that the program more than paid for itself. CONCLUSION: A self-management program for adult asthma effectively reduced the cost associated with asthma. The findings are especially salient because the subjects' asthma was generally under good medical control when they participated in the program. The savings were therefore not the result of improved medical treatment; medical treatment was a controlled parameter, not a variable, in the self-management study. The self-management program for adult asthma was cost-beneficial.

Adult↗

PubMed1995

A self-management program for adult asthma. Part I: Development and evaluation.

BACKGROUND: We developed and evaluated a self-management program for adult asthma. In developing the program, we considered questions of format and behavior control. The format we selected included components known to be effective in educational settings. We regulated asthma management behavior through the introduction of environmental cues. METHODS: Seventy-six subjects, whose asthma was generally under medical control, were assigned randomly to either a treatment group or a waiting-list control group. Those in the treatment group were exposed to a 7-week program that incorporated proven features of providing effective training and establishing behavioral control. Subsequently, subjects in the control group received the treatment. Short-term evaluation of the treatment was made after the subjects in the experimental group were trained but before the control subjects were trained. Long-term evaluation was conducted after both groups of subjects were trained. RESULTS: Over the short term, self-management training led to fewer asthma symptoms and physician visits and improvement in asthma management skills and cognitive abilities. Over the long term, self-management training was related to lower asthma attack frequency, reduced medication use, improvement in cognitive measures, and increased use of self-management skills. CONCLUSIONS: The program improved asthma management in patients whose conditions were already under good medical control. The effects of the program were apparent a year after the conclusion of self-management training.

Adult↗

PubMed1995

Effect of passive antibody on congenital cytomegalovirus infection in guinea pigs.

Cytomegalovirus (CMV) is the most common congenital viral infection, but little is known about the protective immune mechanisms. The guinea pig (gp) model of congenital CMV was used to evaluate the effects of passive antibody given to pregnant dams on pup survival. Dams received three doses of high-titer gpCMV or control antibody on days -3, -1, and +7, or +1, +3, and +7, in relation to gpCMV challenge. gpCMV was inoculated in the late second to early third trimester at three different doses. Compared with controls, gpCMV antibody begun before gpCMV challenge significantly increased pup survival from 14% to 52%, 21% to 84%, and 51% to 77%, respectively, for the three challenge doses. gpCMV antibody started after viral challenge increased pup survival after only the lowest challenge dose (51% to 81%). Antibody did not protect against CMV infection of the pups. CMV antibody appeared to improve survival in congenital CMV infection but did not affect vertical transmission.

Animals↗

PubMed1995

Evaluation of a possible association of urban air toxics and asthma.

The prevalence of asthma, measured either as the frequency of hospital admissions or number of deaths attributed to asthma, has increased over the last 15 to 20 years. Rapid increases in disease prevalence are more likely to be attributable to environmental than genetic factors. Inferring from past associations between air pollution and asthma, it is feasible that changes in the ambient environment could contribute to this increase in morbidity and mortality. Scientific evaluation of the links between air pollution and the exacerbation of asthma is incomplete, however. Currently, criteria pollutants [SOx, NOx, O3, CO, Pb, particulate matter (PM10)] and other risk factors (exposure to environmental tobacco smoke, volatile organic compounds, etc.) are constantly being evaluated as to their possible contributions to this situation. Data from these studies suggest that increases in respiratory disease are associated with exposures to ambient concentrations of particulate and gaseous pollutants. Similarly, exposure to environmental tobacco smoke, also a mixture of particulate and gaseous air toxics, has been associated with an increase in asthma among children. In addition, current associations of adverse health effects with existing pollution measurements are often noted at concentrations below those that produce effects in controlled animal and human exposures to each pollutant alone. These findings imply that adverse responses are augmented when persons are exposed to irritant mixtures of particles and gases and that current measurements of air pollution are, in part, indirect in that the concentrations of criteria pollutants are acting as surrogates of our exposure to a complex mixture. Other irritant air pollutants, including certain urban air toxics, are associated with asthma in occupational settings and may interact with criteria pollutants in ambient air to exacerbate asthma. An evaluation of dose-response information for urban air toxics and biological feasibility as possible contributors to asthma is therefore needed. However, this evaluation is compounded by a lack of information on the concentrations of these compounds in the ambient air and their effects on asthma morbidity and mortality. Through an initial review of the current toxicological literature, we propose a tentative list of 30 compounds that could have the highest impact on asthma and respiratory health. These compounds were selected based on their ability to induce or exacerbate asthma in occupational and nonoccupational settings, their allergic potential and ability to react with biological macromolecules, and lastly, their ability to irritate the respiratory passages. We recommend better documentation of exposure to these compounds through routine air sampling and evaluation of total exposure and further evaluation of biological mechanisms through laboratory and epidemiological studies directed specifically at the role these substances play in the induction and exacerbation of asthma.

Air Pollutants↗

PubMed1995

Machine operator's lung. A hypersensitivity pneumonitis disorder associated with exposure to metalworking fluid aerosols.

Six auto parts manufacturing workers were referred for evaluation of a 6-week history of work-related dyspnea, cough, and fatigue. Two workers also reported fever and weight loss. All six worked in a machining area where a waterbased metalworking fluid was used and recirculated under high pressure, thereby creating an aerosol. Chest radiographs revealed pulmonary interstitial infiltrates in four workers. Lung function tests showed that four workers had decreased diffusing capacity. After removal from the work area, all workers recovered. The metalworking fluid was cultured for bacteria and fungi. Isolates from broth cultures were sonicated to obtain antigen extracts. Serum precipitins to one or more of the microbial isolates were identified in all six workers but not in eight of nine nonexposed control subjects. The most frequent precipitin response (six of six workers) was against antigens of Pseudomonas fluorescens, which was cultured from the metalworking fluid. In all workers, precipitins to at least one other cultured organism were detected; these included Aspergillus niger, Staphylococcus capitas, an acid-fast Rhodococcus sp, and Bacillus pumilus. This represents the first report of hypersensitivity pneumonitis associated with industrial exposure to aerosolized metalworking fluid. Observed precipitin responses to a variety of microbial contaminants in metalworking fluid strongly suggest a causative role for microbial antigens in the induction and elicitation of this manifestation of hypersensitivity pneumonitis.

Adult↗

PubMed1994

A combined respiratory and cutaneous hypersensitivity syndrome induced by work exposure to quaternary amines.

The quaternary amine, benzalkonium chloride, has been associated with cutaneous and mucosal delayed hypersensitivity reactions and with paradoxical bronchoconstriction after use of aerosolized asthma medications. Until now, quaternary amines have not been reported to cause occupational asthma. We describe a case of occupational asthma caused by prolonged exposure to a cleaning solution containing benzalkonium chloride in the workplace. Single-blind, placebo-controlled, open-room challenges were performed to determine the specific agent responsible for the patient's symptoms. Pulmonary function and epicutaneous challenge tests were also performed. The patient had positive responses to challenges with a liquid toilet bowl cleaner containing benzalkonium chloride but was unreactive to other agents tested. Removal from the workplace resulted in complete resolution of symptoms. The exact mechanisms responsible for occupational asthma induced by quaternary amines remain unknown; however, this case emphasizes the importance of recognizing reactive chemicals as possible causes.

Adult↗

PubMed1994

Characterization of skin prick testing responses for detecting sensitization to detergent enzymes at extreme dilutions: inability of the RAST to detect lightly sensitized individuals.

We observed that a group of detergent enzyme workers with known exposure to the subtilisin enzyme, Alcalase (Novo Industries, Bagsvaerde, Denmark), exhibited percutaneous sensitivity to Savinase (Novo Industries), a microbial protease, to which there was no previous occupational exposure. This was attributed to either cross-reactivity between these enzymes or to foreign enzyme contaminants contained in the Savinase antigen. The aims of this study were to determine the range of concentrations eliciting percutaneous responses to Alcalase and to another enzyme, Rapidase (an alpha-amylase) (Gist Brocades, Belgie, Netherlands); to compare the sensitivity of RAST and skin prick testing; and to characterize the relationship between wheal size and antigen concentration. Prick testing was conducted over six log10 antigen dilutions of Alcalase and Rapidase in 30 workers with previous exposure and skin reactivity to enzymes (group 1) and compared to nonexposed control groups, which included 60 atopic subjects (group 2) and 30 nonatopic subjects (group 3). The RAST was performed with Alcalase and Rapidase antigens. The percutaneous threshold concentrations in group 1 subjects varied widely from 10(3) to 10(-3) micrograms of protein per milliliter. Of 19 group 1 workers with skin test reactivity to Alcalase, 84% had positive RAST results; 83% of 24 workers who were reactive to Rapidase had positive RAST results. It was concluded that skin prick testing is preferred over in vitro methods for longitudinal monitoring of human sensitization to workplace allergens. In addition, the data predicted that based on a known Alcalase level of 0.07% in Savinase, 26% of Alcalase-sensitized subjects could react to Savinase. An excellent correlation (r > 0.97) was found between log concentration of antigen and wheal size parameters, with the log diameter and log area performing equally as well (r > 0.98). Analysis of variance revealed that more than 60% of intragroup variation represented human variability in wheal parameters at each concentration tested, whereas at least 95% of intergroup variation was due to regression. The excellent correlations of both wheal diameter and area with antigen concentrations were attributed to the very small changes observed between test concentrations.

Allergens↗

PubMed1994

Solar simulator-induced herpes simplex labialis: use in evaluating treatment with acyclovir plus 348U87.

Models of UV radiation induced herpes labialis utilizing crude light sources have previously been used to examine the efficacy of antivirals. We sought to improve upon this model by using a solar simulator. Initial studies revealed that 13 of 34 (38%) subjects with a history of recurrent HSV labialis receiving three minimal erythema doses (MED's) of UV light developed herpes labialis. We next evaluated the effects of combined therapy with topical ACV and 348U87, a ribonucleotide reductase inhibitor, begun immediately after UV exposure for the prevention and treatment of herpes labialis. No significant reduction in the incidence or severity of herpes labialis was detected although the study was terminated after the interim analysis revealed no benefit, thus reducing the power to detect a difference. This lack of effect may be explained by the general poor efficacy of topical treatment for recurrent HSV infection. Further studies of ACV + 348U87 in vehicles that should increase the penetration and stability of the drugs are planned.

Acyclovir↗

PubMed1994

Protection against rotavirus disease after natural rotavirus infection. US Rotavirus Vaccine Efficacy Group.

Determination of protective efficacy after natural rotavirus infection is important as a basis for evaluating rotavirus vaccines. Therefore, placebo recipients in a large 2-year rotavirus vaccine trial conducted across the United States were followed to determine the protection afforded by natural rotavirus infection. Serotype 1 rotaviruses predominated (93% year 1, 66% year 2), but isolates of all four major human rotavirus serotypes circulated during both years. Of the 45 placebo recipients with documented rotavirus illnesses in year 1, 1 developed rotavirus disease in year 2 compared with 29 of the other 235 placebo recipients (P = .03). Serologic data were available for 171 placebo recipients, and 37 of 140 without rotavirus illnesses in year 1 had evidence of asymptomatic rotavirus infection. None of these 37 experienced rotavirus disease in year 2 compared with 22 of the remaining 103 (P < .001). Overall efficacy after natural rotavirus infection was 93% (95% confidence interval, 50%-99%).

Antibodies, Viral↗