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Context: A high priority in vaccine research is the development of influenza vaccines that do not use embryonated eggs as the substrate for vaccine production.Objective: To determine the dose-related safety, immunogenicity, and protective efficacy of an experimental trivalent influenza virus hemagglutinin (rHA0) vaccine produced in insect cells using recombinant baculoviruses.Design, Setting, and Participants: Randomized, double-blind, placebo-controlled clinical trial at 3 US academic medical centers during the 2004-2005 influenza season among 460 healthy adults without high-risk indications for influenza vaccine.Interventions: Participants were randomly assigned to receive a single injection of saline placebo (n = 154); 75 microg of an rHA0 vaccine containing 15 microg of hemagglutinin from influenza A/New Caledonia/20/99(H1N1) and influenza B/Jiangsu/10/03 virus and 45 microg of hemagglutinin from influenza A/Wyoming/3/03(H3N2) virus (n = 153); or 135 microg of rHA0 containing 45 microg of hemagglutinin each from all 3 components (n = 153). Serum samples were taken before and 30 days following immunization.Main Outcome Measures: Primary safety end points were the rates and severity of solicited and unsolicited adverse events. Primary immunogenicity end points were the rates of 4-fold or greater increases in serum hemagglutinin inhibition antibody to each of the 3 vaccine strains before and 28 days after inoculation. The prespecified primary efficacy end point was culture-documented influenza illness, defined as development of influenza-like illness associated with influenza virus on a nasopharyngeal swab.Results: Rates of local and systemic adverse effects were low, and the rates of systemic adverse effects were not different in either vaccine group than in the placebo group. Hemagglutinin inhibition antibody responses to the H1 component were seen in 3% of placebo, 51% of 75-microg vaccine, and 67% of 135-microg vaccine recipients, while responses to B were seen in 4% of placebo, 65% of 75-microg vaccine, and 92% of 135-microg vaccine recipients. Responses to the H3 component occurred in 11% of placebo, 81% of 75-microg vaccine, and 77% of 135-microg vaccine recipients. Influenza infections in the study population were due to influenza B and A(H3N2), and influenza A infections were A/California/7/2004-like viruses, an antigenically drifted strain. Seven cases of culture-confirmed CDC-defined influenza-like illness occurred in 153 placebo recipients (4.6%) compared with 2 cases (1.3%) in 150 recipients of 75 microg of vaccine, and 0 cases in recipients of 135 microg of vaccine.Conclusions: In this study, a trivalent rHA0 vaccine was safe and immunogenic in a healthy adult population. Preliminary evidence of protection against a drifted influenza A(H3N2) virus was obtained, but the sample size was small. Inclusion of a neuraminidase component did not appear to be required for protection.Trial Registration: clinicaltrials.gov Identifier: NCT00328107. [ABSTRACT FROM AUTHOR]

Background: Influenza-virus hemagglutinin (HA) protein expressed in insect cells by recombinant baculovirus is a candidate influenza vaccine., Methods: In a randomized, double-blind trial conducted in 399 adults > or = 65 years of age, the efficacy of trivalent inactivated influenza vaccine (TIV) licensed for intramuscular injection was compared with that of trivalent baculovirus-expressed HA vaccine administered at doses of 15 microg, 45 microg, or 135 microg of each HA., Results: Compared with TIV, baculovirus-expressed HA vaccine was safe and induced better serum antibody responses to the H3 component when administered at doses of 45 microg or 135 microg of each HA., Conclusions: Baculovirus-expressed HA is a safe and immunogenic influenza vaccine in elderly adults.

A total of 35 volunteers were recruited for an IRB-approved inpatient dose-escalation challenge. The goal was to identify a dose that produced an observed cholera attack rate > or =80% and an illness of sufficient severity during the defined study period such that the model would be useful for determining vaccine protection. Volunteers were challenged in groups of 5 with V. cholerae O139 that had been reconstituted immediately before use. Only 2 out of 5 volunteers who received the lowest dose (4.3 x 10(4) cfu) had diarrhea. As the inoculum size increased, the attack rate of diarrhea increased to 3-4 of 5 volunteers. At the highest dose tested, approximately 5 x 10(7) cfu, the attack rate was 73%. We recommend the use of frozen V. Cholera O139 in a human experimental challenge model to assess cholera vaccine efficacy (VE) in a cholera endemic area but with 4 days observation period before initiation of tetracycline to allow assessment of severity.

A randomized, double-blind study assessed the efficacy and safety of pleconaril, a novel antiviral drug with broad-spectrum activity against picornaviruses, in the treatment of 33 adults with an experimentally induced viral respiratory infection. Subjects received either pleconaril 200 mg twice daily (initial dose of 400 mg) or placebo for 7 days. Fourteen hours after receiving the initial dose of either pleconaril or placebo, subjects were inoculated intranasally with 100 plaque-forming units of coxsackievirus A21. Results revealed statistically significant reductions in viral shedding in nasal secretions (P<.001), nasal mucus production (P=.004), and total respiratory illness symptom scores (P=.013) in pleconaril-treated as compared with placebo-treated subjects. The most common adverse events were nausea and abdominal pain. These data support the safety and efficacy of pleconaril in decreasing the signs and symptoms and viral shedding associated with a viral respiratory infection.

The safety and immunogenicity of an orally administered live human rotavirus vaccine candidate (89-12), attenuated by 33 passages in monkey kidney cells, were evaluated in placebo-controlled trials in adults, children and infants. This strain was selected because natural infections with 89-12-like rotaviruses provided 100% protection over two years. The initial evaluations in adults, seropositive children and nine infants indicated that the vaccine was safe. Two doses of vaccine (10(5) p.f.u. dose-1) or placebo were then given to 42 infants, aged from 6 to 26 weeks. No significant difference in side effects was seen. Seroconversion was demonstrated in 19 of 20 previously uninfected vaccine recipients, but > or = 4-fold rises in 89-12 neutralizing antibody titers were detected in only seven subjects. Intestinal IgA responses were detected in 15 subjects. This attenuated human rotavirus was safe and immunogenic and should be further evaluated as a vaccine candidate.

Purpose: A prospective, two-armed, open-label, randomized trial was performed to compare the geometric mean titers (GMT), seroprotection (SP) and seroconversion (SC) rates found after administration of two doses of recombinant hepatitis B vaccine., Methods: Recombinant hepatitis B vaccine 10 or 20 micrograms was administered IM at 0, 1, and 6 months in healthy adolescents., Results: Volunteers who received either dose of the vaccine had similarly high seroconversion and seroprotection rates at all visits. At Month 8, both doses of the vaccine were highly immunogenic with GMTs of 1989 mIU/mL (10 micrograms dose) and 7672 mIU/mL (20 micrograms dose) and nearly equivalent SP rates (97% and 99% in the 10 and 20 micrograms dose groups, respectively). The geometric mean titers of seroconverters at Months 3, 6 and 8 were significantly greater in the 20 micrograms group as compared to the 10 micrograms group (p < or = 0.003). Both doses were well-tolerated, with injection site pain the most common reported adverse event. Injection site pain was reported significantly (p = 0.004) more by volunteers who received the 20 micrograms dose (10.7%) compared with volunteers who received the 10 micrograms dose (3.8%)., Conclusion: Vaccination with 10 micrograms of recombinant hepatitis B vaccine may provide a clinically effective and economical alternative to the use of the 20 micrograms dose in healthy adolescents.

A simple, sensitive, and specific one step polymerase chain reaction (PCR) method for the detection of hepatitis C virus (HCV) RNA in infected patients' serum or plasma samples is described. We performed the one step PCR amplification in combination with the initial step of reverse transcription by using oligonucleotide primers derived from the conserved 5'-untranslated region (5'-UTR) of the HCV genome. By utilizing this strategy, there was no need for nested or second stage PCR amplification. The PCR products (cDNAs) were easily visualized by agarose gel electrophoresis and ethidium bromide staining. Furthermore, the PCR products were characterized by Southern blot hybridization and DNA sequencing. We then used the one step PCR amplification method to detect the presence of HCV RNA in several infected patients' samples with acute and chronic infections. There was a 100% concordance between the results of PCR and second generation recombinant immunoblot assay (RIBA II). In addition, this method was found to be useful in determining viremia in HCV infected patients with indeterminate RIBA II results. The 5'-UTR of the HCV genome, being the most conserved region among different viral isolates, could be amplified by PCR for the detection of HCV RNA, as shown here, as well as serving as a potential target for antiviral agents.

The safety and immunogenicity of a booster dose of a new acellular pertussis component diphtheria-tetanus toxoids-pertussis vaccine (DTaP) were compared with whole cell pertussis component diphtheria-tetanus toxoids-pertussis vaccine (DTwP). Fifty children ages 15 to 18 months and 50 children ages 4 to 6 years were studied. The incidence of adverse reactions observed during the first 72 hours after vaccination in the DTaP/DTwP vaccinees were: pain, 32%/92% (P < 0.001); redness, 14%/24% (P = 0.2); swelling, 2%/14% (P < 0.03); fever, 52%/90% (P < 0.001); drowsiness, 14%/34% (P < 0.05); fussiness, 32%/88% (P < 0.001); and unusually poor appetite, 6%/42% (P < 0.001). The geometric mean titers of anti-pertussis toxin and anti-filamentous hemagglutinin antibody were also significantly (P < 0.001) higher in the DTaP compared to the DTwP recipients. When administered as a booster dose this DTaP vaccine, which has been chosen by the NIH for the second pertussis vaccine clinical efficacy trial, was more immunogenic for pertussis toxin and filamentous hemagglutinin and caused fewer and less severe adverse reactions compared with the Connaught DTwP vaccine used in this study.

This case-control study sought to determine whether protection against clinically significant rotavirus diarrhea in children aged 4-35 months correlated with titers of serum neutralizing antibody and, if so, whether this protection was serotype-specific. Titers of acute-phase sera from 156 cases of treated rotavirus diarrhea in rural Bangladesh were contrasted with titers from 312 contemporaneously selected, age-matched controls. Analyses of the culture-adapted rotaviruses from the cases revealed that 24%, 15%, 43%, and 17% belonged to serotypes 1-4, respectively. Titers of both homologous and heterologous neutralizing antibody in acute blood specimens of cases were significantly lower than those of matched controls. However, multivariate logistic regression models demonstrated that only antibody titers to heterotypic rotaviruses were independently associated with protection against rotavirus disease. These data, which indicate that the correlation of protection with neutralizing antibody titers is not serotype-specific, suggest that immunity to rotavirus disease may be mediated by other factors.

An enzyme-linked immunosorbent assay (ELISA) was developed by using a synthetic polypeptide (SP) whose sequence was derived from the structural region of hepatitis C virus (HCV). Results of several coded panels of sera obtained from volunteer blood donors and patients with apparent non-A, non-B hepatitis and/or hepatitis B virus used in this ELISA were compared with those of a commercially available first-generation C-100 ELISA (using nonstructural HCV antigens), an experimental second-generation C-200/C-22 ELISA (using both structural and nonstructural HCV antigens), and recombinant immunoblot assays RIBA-I and RIBA-II. In the majority of cases, the results obtained with the HCV-SP ELISA correlated well with those obtained by RIBA-II and C-200/C-22 ELISA. In contrast, many samples that were repeatedly reactive in the C-100 ELISA results were nonreactive with RIBA and HCV-SP ELISA. In addition, HCV-SP detected HCV-specific antibody that appeared within a month of infection and coincided with the earliest increase in alanine aminotransferase. In summary, we have developed an ELISA based on a structural HCV synthetic polypeptide, HCV-SP, that has high specificity and sensitivity and is capable of detecting specific antibodies in the acute phase of HCV infection.

To determine whether salivary antibody is a reliable indicator of rotavirus infection and mucosal rotavirus antibody concentrations, salivary rotavirus antibody titers were determined as a function of time following inoculation of 24 adult volunteers with a virulent strain of human rotavirus (CJN). Twenty of the subjects became infected and all produced detectable amounts of salivary rotavirus IgA. These antibody concentrations remained undetectable in the four uninfected subjects. Rises of greater than or equal to fourfold in either salivary rotavirus IgA or neutralizing antibody to the challenge virus were detected in all but two subjects. The titers of both antibodies were maximal at 13 days after inoculation and decreased significantly (p less than .02) by 27 days, a result very similar to that previously found with stool rotavirus IgA in CJN-infected subjects. These results suggest that salivary rotavirus antibody titers are an accurate reflection of mucosal rotavirus antibody and a possible surrogate for intestinal rotavirus antibody.

To determine the effect of cholera toxin as a mucosal adjuvant on the class and subclass antibody response to RSV, mice were immunized intranasally with different doses of live RSV or UV-inactivated RSV mixed with cholera toxin. A single 10(6) pfu dose of live RSV and a single 50 micrograms dose of UV-inactivated RSV mixed with cholera toxin produced comparable serum IgG and respiratory secretion IgG and IgA antibody titers. Subclass antibody titers to whole RSV were also comparable between these two immunizing regimens. A predominance of IgG2a subclass to whole RSV was found for both regimens. The quantity of serum total IgG antibody to glycoprotein F or glycoprotein G did not differ between these regimens. The serum IgG subclass antibody response to both glycoprotein F and G was also not significantly different between regimens. Cholera toxin as a mucosal adjuvant can stimulate class and subclass antibody responses to UV-inactivated RSV that are similar in quantity and distribution to those after live RSV infection.

To determine the effect of viral dose and replication on the subclass antibody response to RSV, mice were immunized intranasally with different doses of live RSV (10(4)-10(6) pfu) and compared to mice given an immunizing regimen of UV-inactivated RSV. Mice given the 10(6) pfu dose of live RSV and mice given the 40 micrograms dose of UV-inactivated RSV had comparable class specific antibody responses to whole RSV in serum and respiratory secretions. Serum from these two groups of mice were then compared for IgG subclass response to whole RSV. A predominance of IgG2a subclass antibody was found for both immunizing regimens, and no significant differences in subclass proportions were noted between regimens. These two regimens were then compared for serum total IgG response to RSV surface glycoproteins F and G. The serum IgG response to these glycoproteins was lower after immunization with UV-inactivated RSV than after live-RSV immunization (F: P = 0.03; G: P less than 0.05), even though the serum IgG response of the two groups to whole RSV was comparable. The IgG subclass response to surface glycoproteins was evaluated for live RSV immunization. The proportions of subclass antibody responses to glycoprotein F were comparable to the subclass response proportions to whole RSV and were not characteristic of a T-dependent response pattern. The subclass profile for glycoprotein G was not comparable to that of whole RSV but was suggestive of a T-independent response pattern.

Group A rotaviruses collected between 1985 and 1986 during comprehensive surveillance of treated diarrheal episodes occurring in a rural Bangladesh population were culture adapted and characterized by electropherotype, serotype, and subgroup. Of 454 episodes of rotavirus-associated diarrhea, rotaviruses were culture adapted from 381 (84%), and 335 contained 11 electrophoretically identical segments in unpassaged and cultured preparations. These 335 comprised 69 different electropherotypes with between 1 (32 isolates) and 79 representatives. The persistence of specific rotavirus strains within the study population, as defined by the detection of viruses with particular electropherotypes, was generally limited to a period of only a few months. All 335 isolates were serotyped by neutralization with hyperimmune antisera to prototype rotavirus strains representative of serotypes 1 to 4, i.e., Wa, DS-1, P, and ST-3. It was found that 80, 48, 119, and 88 isolates belonged to serotypes 1 to 4, respectively. The concentrations of hyperimmune antisera required to neutralize these isolates, however, were at least threefold greater than those needed to neutralize the homologous strains. Therefore, the isolates appeared to have altered neutralization epitopes from their prototype strains. Furthermore, the serotype 4 isolates were consistently shown to be much more closely related to the serotype 4B VA70 strain than the serotype 4A ST-3 strain. All but two isolates identified as serotypes 1, 3, or 4 had long electropherotypes and were subgroup II, and all but one serotype 2 isolate were subgroup I and had short electropherotypes. The three disparate strains appeared to be genetic reassortants. Evidence is presented that dual infections required for reassortant formation were not uncommon. Thus, formation of multiple reassortants may have been a cause for the observed rapid shift in viral strains within the study population.

A model was developed to examine the effects of disinfectants on the transmission of infectious rotavirus from a dried surface to humans. The initial experiments were designed to find a method of preserving rotavirus infectivity during drying. Culture-adapted human rotavirus (CJN strain) was dried at room temperature in different organic suspensions, including fecal matter, several laboratory media, and nonfat dry milk (NDM). Recoveries of infectious virus were then compared. Fecal matter provided little protection in this study relative to distilled water, but the other suspensions were quite protective, especially NDM, which consistently allowed recoveries of greater than 50%. When 10(3) focus-forming units of unpassaged CJN virus were dried in NDM and administered to subjects who licked the dried material, 100% (8 of 8) became infected. The effect of Lysol brand disinfectant spray (LDS) was next examined. Although NDM provided some protection against inactivation by LDS, spraying under conditions recommended by the manufacturer consistently caused the CJN virus titer to decrease greater than 5 log10. Consumption of CJN virus (10(3) focus-forming units) sprayed with LDS caused no infection in 14 subjects, whereas 13 of 14 subjects who consumed the unsprayed virus became infected (P less than 0.00001). The methods developed in this study could be used to test the effects of other disinfectants on the spread of infectious rotavirus from inanimate surfaces to humans.

To measure protection induced by natural rotavirus infection, 163 infants enrolled in a rotavirus vaccine trial were prospectively followed for 2 years. Serotype 1 rotaviruses were the predominant circulating strains during the study. Over the 2 years of observation, significantly fewer infants infected before enrollment developed a symptomatic reinfection (0 of 21) or any reinfection (4 of 21) compared with previously uninfected infants (P = .0003). Of the 60 infants who developed a primary rotavirus infection in the first year (40 symptomatic, 20 asymptomatic) only 4 were reinfected in the second year compared with 29 of 82 subjects not previously infected (P = .00003). Asymptomatic primary infection appeared to be as protective as symptomatic primary infection. The only symptomatic reinfections occurred in 2 subjects who did not develop rotavirus antibody after the initial detection of rotavirus. An age-related reduction in the ratio of symptomatic to asymptomatic primary rotavirus infection was also detected. In this study, protection against homotypic serotype 1 reinfection appeared to last greater than or equal to 2 years.

The purpose of this pilot study was to determine whether complement is activated in the upper respiratory tract during experimental influenza virus infection in human volunteers. Seven subjects were challenged with influenza A/Bethesda/1/85 (H3N2), and four subjects received placebo. C3a and C5a concentrations were measured by radioimmunoassay in nasal lavage fluids before challenge and for 8 days after challenge. A significant increase (p less than 0.05) in C3a and C5a concentrations was demonstrated in lavage fluids from subjects who developed influenza illness as compared with uninfected control subjects and infected subjects who remained asymptomatic. Maximal levels of C3a and C5a were detected during the recovery phase of illness. These results suggest that complement is activated in the airway in response to influenza illness.

In an evaluation of WC3 bovine rotavirus (serotype 6) vaccine in infants, some subjects experienced a natural serotype 1 rotavirus infection before vaccination and others after. Therefore, the effects of both WC3 and natural rotavirus strains as either primary or boosting immunogens on serotype-specific neutralizing antibody responses could be determined. After primary natural infection (symptomatic or asymptomatic), neutralizing antibody titers were highest to serotype 1 but were consistently high to serotype 3, and low titers (greater than or equal to 20) to serotypes 2 and 4 were often detected. Previous vaccination with WC3 had little effect on the magnitude of these responses. In contrast, subjects infected with serotype 1 strains before vaccination experienced large (average, 12-fold) rises in neutralizing antibody to human serotypes 1-4 when vaccinated with WC3. Thus, although WC3 and the natural strains are distinct serotypes, their epitopes were sufficiently similar that reinfection with WC3 could boost neutralizing antibody titers to human serotypes in subjects primed by a previous natural infection.

The safety, immunogenicity, and efficacy of WC3 rotavirus vaccine was evaluated in a double-blind, placebo-controlled trial of healthy infants 2-12 months of age; 103 received one dose of vaccine and 103 received placebo. Vaccination appeared to be safe and induced an antibody response (WC3 neutralizing antibody) in 97% of vaccinees. Only 9 (9%) of these, however, produced antibody to human rotavirus serotypes; at least 7 of the 9 were naturally infected before vaccination. Neither the number of symptomatic episodes of rotavirus diarrhea (21 vs 25) nor the number of moderate to severe rotavirus illnesses (9 vs. 15) was significantly different in vaccine or placebo recipients, respectively, during a predominantly serotype 1 rotavirus season. A slight but significant decrease in mean symptom score was detected in vaccine recipients. Despite an overall lack of efficacy, protection could be correlated to previous rotavirus infection, high levels of WC3 neutralizing antibody, and preexisting (maternal) serotype 1 neutralizing antibody with a titer greater than or equal to 30.

Based on the concept of a common mucosal immune system, the murine gastrointestinal tract was inoculated (oral) with three doses (5, 20, and 40 micrograms) of UV-inactivated respiratory syncytial virus (RSV) in order to elicit a virus-specific immune response in the respiratory tract. Only the 40 micrograms dose induced significant (P less than 0.01) anti-RSV-IgG rises in serum and lung wash compared to controls. To improve the immune response, mice were immunized intranasally under light anesthesia with the same 40 micrograms dosage regimen of killed RSV so that each dose passed through the nose and was swallowed. This combined nasal/oral immunization stimulated anti-RSV-IgG in serum, lung wash and nasal wash (P less than 0.001) and anti-RSV-IgA in lung and nasal wash (P less than 0.001) that were comparable to levels after infection with live RSV. Three days after challenge with live RSV, mice given combined nasal/oral immunization showed suppressed nasal virus shedding (P = 0.025). Nasal virus shedding correlated inversely with concentrations of anti-RSV-Ig in nasal secretions but did not correlate with concentrations in serum.

Of 335 rotavirus isolates associated with diarrheal disease in Bangladesh that were culture adapted and subsequently characterized for electropherotype, subgroup, and serotype, 9 had properties that suggested they may be natural reassortants between human rotaviruses belonging to different "genogroups." Two of these were examined in greater detail by RNA-RNA hybridization with prototype strains representative of each of the three proposed human rotavirus genogroups. One subgroup II isolate, 248, with a "long" electrophoretic pattern was neutralized by hyperimmune antisera to both serotype 2 and 4 strains. Consistent with these results, seven RNA segments of this isolate formed hybrids with human strains belonging to the Wa genogroup and four segments hybridized with strains belonging to the DS-1 genogroup. The second isolate examined, 456, belonged to subgroup II and had a long electrophoretic pattern but was found to be a serotype 2 strain. This isolate also appeared to be an intergenogroup reassortant because three of its segments formed hybrids with strains belonging to the Wa genogroup and eight hybridized with viruses of the DS-1 genogroup. On the basis of the relative migration rates of these RNA-RNA hybrids during gel electrophoresis, a suggested origin for each gene segment was proposed which was consistent with the results expected from electrophoretic, subgroup, and serotypic analyses.

Serum specimens from infants 2 to 12 months old vaccinated with the WC3 bovine rotavirus were analyzed to determine the relative concentrations of neutralizing antibody to the VP4 and VP7 proteins of the vaccine virus. To do this, reassortant rotaviruses that contained the WC3 genome segment for only one of these two neutralization proteins were made. The segment for the other neutralization protein in these reassortants was from heterotypic rotaviruses that were serotypically distinct from WC3. Sera were examined from 31 infants who had no evidence of a previous rotavirus infection and the highest postvaccination WC3-neutralizing antibody titers (i.e., 160 to 600) of the 103 subjects administered the vaccine. A reassortant (3/17) that contained both neutralization proteins from the heterotypic rotaviruses, i.e., EDIM (EW strain of mouse rotavirus) VP7 and rhesus rotavirus VP4, was not neutralized by these sera (geometric mean titer [GMT], less than 20). A reassortant (E19) that contained EDIM VP7 and WC3 VP4 was also very poorly neutralized by these antisera (GMT = 20). In contrast, antibody titers to a reassortant (R20) that contained WC3 VP7 and rhesus rotavirus VP4 were higher than those against WC3 (GMTs of 458 and 313, respectively). Thus, VP7 appeared to be the dominant immunogen for production of neutralizing antibody after intestinal infection of previously uninfected infants vaccinated with WC3 bovine rotavirus.

Previous studies of adults challenged with human rotavirus (CJN strain) showed that 74% became infected and 55% of those infected experienced illness. Protection against infection correlated with rotavirus antibody, most significantly (P = .005) serum rotavirus IgG. In this study, 20 previously challenged subjects were reinoculated with the same virus 9-12 months after their initial challenge. Only 1 of 8 subjects not infected after the initial challenge and 2 of 12 infected after the first inoculation became infected after reinoculation; none became ill. Titers of rotavirus antibodies (serum, jejunal, and stool) at the time of reinoculation were about as high as or higher than they were before the initial inoculation. This correlated with greater protection, but the extent of protection was significantly greater (P less than .0001) than predicted based on a previous model relating protection and preinoculation titers of serum rotavirus IgG. Thus, inoculation with human rotavirus provided homotypic protection for at least 9-12 months, and protection remained correlated with higher concentrations of rotavirus antibody. However, the specific relationship between protection and rotavirus antibody was altered after the initial inoculation.

Four influenza A challenge studies were performed over a period of three years using the same dose of one virus pool. The first three studies were conducted two influenza seasons apart from the last study. In all four studies only subjects with screening hemagglutination inhibition (HAI) antibody titers less than or equal to 1:8 in sera were accepted as study subjects. The rate of infection after influenza challenge was 96% (25 of 26) in the first three studies, and only 73% (8 of 11) in the last study (P less than 0.04). The rate of influenza illness in the first three studies was 62% (16 of 26), and only 9% (1 of 11) in the last study (all subjects: P = 0.003; infected subjects: P = 0.01). Even though screening HAI titers were comparable between groups, prechallenge serum influenza-specific IgG titers correlated inversely with respiratory symptoms (P = 0.04). Prechallenge nasal wash influenza-specific IgA titers were lower in subjects who developed influenza illness (P = 0.03). Prechallenge influenza-specific nasal wash ELISA-IgA titers and serum ELISA-IgG titers predicted influenza severity in patients prescreened by HAI during influenza challenge studies.

The incidence of rubella and the congenital rubella syndrome has decreased dramatically in the United States since rubella vaccine became available in 1969. A marked shift in susceptibility rate has occurred so that 70% of current rubella cases involve teenagers and young adults. The history of rubella control is reviewed. Future research as well as altered public health strategies are suggested to optimize rubella control.

An unpassaged, safety-tested strain (CJN) of human rotavirus from a stool specimen of a hospitalized child was administered orally to 62 adult volunteers for determination of the dose required to produce infection with or without illness. Subjects ingested doses ranging from 9 X 10(-3) to 9 X 10(4) focus-forming units in buffered salt solution after consumption of 50 ml of 4% NaHCO3. The amount of virus in the inoculum required to cause infection (shedding of virus, seroconversion, or both) in study subjects was comparable to the minimum detectable in cultures of primary monkey kidney cells. Seventeen of 30 infected subjects became ill with doses equivalent to that required for infection. Although the preinoculation titers of serum neutralizing antibody to the challenge virus in study subjects ranged from less than 1:2 to 1:1,600, the concentration of serum antibody could not be correlated with protection from infection or illness in subjects given an infectious dose of virus.

A live, attenuated, recombinant influenza vaccine (Alice strain) administered intranasally was evaluated in high school students and compared with intranasal placebo and subcutaneous, inactivated, bivalent influenza vaccine. The Alice strain was antigenic, increasing the geometric mean titer (GMT) from a prestudy level of 30.2 to a postvaccine level of 189.6. The inactivated vaccine increased the GMT from 32.9 to 361.8. There was no increase in the GMT among the placebo recipients. The Alice strain produced little reaction. With an antigenic, safe, acceptable, live, attenuated influenza vaccine available, immunization on a widespread basis should be considered.

Studies were conducted of experimental challenge with rubella virus in vaccinees whose possession of vaccine-induced antibody after vaccination had been documented and whose antibody level had become undetectable or very low over time. The challenge virus was the Howell strain, which had been shown to produce typical clinical and laboratory features of rubella in susceptible persons. The challenge of the vaccinees resulted in local viral replication in all but one; in viremia, a primary immunologic response, and a secondary antibody response in some; and usually in illness without a rash or in subclinical infection. The results emphasize the importance of continuing careful clinical and laboratory surveillance of vaccinees for determining the persistence of vaccine-induced immunity and of considering methods for identifying and revaccinating the minority of vaccinees who lose such immunity.

The ferret model of influenza A infection was evaluated to determine whether physical signs of influenza illness in addition to fever could be adequately followed. Ferrets were evaluated for nasal and systemic signs of influenza infection in a blinded, randomized protocol. Nasal signs were scored depending on the degree of nasal discharge and congestion. Systemic signs were evaluated on the basis of the activity level of ferrets. Nasal and systemic signs in ferrets challenged with influenza began to rise at peak virus shedding. This rise was coincident with the onset of the nasal inflammatory cell response. Nasal and systemic signs were statistically higher in challenged ferrets as compared with controls from 28 to 52 h after infection [P = 0.002 except at 28 h (P = 0.01)]. Despite precautions against influenza transmission, controls shed influenza virus associated with mild increases in nasal and systemic signs late in the course of the study. Our results suggest that severity of influenza illness can be adequately assessed in the ferret model using collective measurements of nasal and systemic signs, temperatures, and nasal cellular infiltration.

In vitro lymphocyte proliferation in response to phytohemagglutinin and streptokinase-streptodornase and delayed dermal hypersensitivity to several antigens were assessed in patients with mild viral upper respiratory infections. The response to phytohemagglutinin in 18 patients was not diminished during the viral infection. Deoxyribonucleic acid synthesis induced by streptokinase-streptodornase remained unaffected by the viral illness in five patients, and skin test reactivity was not depressed during the viral infection. Thus, it appeared that localized viral upper respiratory infections were not associated with suppression of systemic cell-mediated immunity.

In a 7 1/2-year follow-up evaluation of the duration of rubella-vaccine-induced immunity of students who received either HPV-77 DK-12 or Cendehill vaccine, both groups showed a continous decline in hemagglutination-inhibition antibody from seven weeks after vaccination but a lower decline between 4 1/2 and 7 1/2 years after vaccination. However, at 7 1/2 years only 16 students (8%) receiving the Cendehill vaccine and one student (0.5%) receiving the HPV-77 DK-12 vaccine lacked detectable antibody. Despite the persistence of antibody titers, there was evidence of subclinical rubella among both groups of vaccinated students. These results emphasize the importance of continued evaluation of the conditions of persons receiving rubella vaccine.

Two different animal models were studied to determine whether localized upper respiratory tract viral infection was associated with suppression of systemic cell-mediated immunity. During influenza infection in ferrets, there was no significant decrease in lymphocyte responsiveness to phytohemagglutinin (PHA). Guinea pigs given influenza showed no significant change in their response to PHA or to picryl human serum albumin (picHSA), to which they had been immunized previously. Delayed hypersensitivity skin test responses to picHSA in guinea pigs remained intact during infection. No change in the percentage of circulating T lymphocytes was detected during influenza infection. Transfer of immunity to nonsensitized recipient guinea pigs from picHSA-sensitized guinea pigs was accomplished during influenza infection. Lack of a suppressive effect on systemic cell-mediated immunity after influenza challenge in these two animal models of mild influenza confirmed previous findings in humans with mild influenza infection.

In a randomized double-blind trial of aerosolized ribavirin for the treatment of influenza B virus infection, no significant difference was found in the febrile course or symptom score of the ribavirin-treated versus placebo-treated patients. The apparent lack of efficacy in this study as compared with that in previous studies is unexplained.

Cell-mediated immunity (CMI) was assessed during infection and after convalescence in 12 patients with influenza pneumonia and 10 patients with bacterial pneumonia. The patients with influenza pneumonia had a marked impairment of skin test reactivity, and their lymphocytes showed a diminished response to phytohemagglutinin and streptokinase-streptodornase stimulation in vitro. Suppression of CMI was related to the severity of the pneumonia. Patients with bacterial pneumonia showed as great a suppression of the response to phytohemagglutinin and streptokinase-streptodornase as the patients with viral pneumonia. All parameters of CMI returned to normal in both groups after convalescence. The depression of CMI could not be related to a decrease in the number of thymus-derived lymphocytes or to serum-suppressive factors in these patients.

An evaluation of two doses of split-product A/New Jersey/76 virus vaccines was conducted at a boys' summer camp. Two doses of either 200 chick cell-agglutinating (CCA) or 400 CCA units of vaccine were administered four weeks apart. There were no significant side effects. Of 60 subjects, 59 developed a significant titer of serum antibody after two doses. There was no correlation between titer of antibody and total dose of vaccine. Younger subjects developed a higher titer than older subjects. A single dose of vaccine was insufficient to achieve a protective level of antibody.

Anti-influenza serum and nasal antibody titers were followed during a double-blind, placebo-controlled, randomized study assessing the prophylactic efficacy of 50, 100, and 200 mg/day of amantadine hydrochloride against experimental challenge with influenza A/Beth/1/85. The geometric mean titers (GMT) of serum hemagglutination inhibition antibody (P = .05) as well as serum influenza-specific IgG (P = .004) were significantly lower for all amantadine groups when compared to placebo. There were no significant differences in the GMT of either type of serum antibody titer comparing any of the three amantadine groups. Viral titers were also lower in the amantadine groups compared to the placebo group and not significantly different among the three amantadine groups. Nasal antibody titers in the 100-mg and 200-mg amantadine groups were significantly lower than placebo titers (P = .002). Nasal antibody titers in the 50-mg amantadine group did not differ significantly from titers in the placebo group (P = .892). Possible reasons for the differential effect of amantadine on the serum and nasal antibody response are discussed.

An evaluation of the safety and immunogenicity of WC3 rotavirus vaccine was evaluated in adult volunteers. Pre- and post-vaccination titers of neutralizing antibody to WC3 and to the four human rotavirus serotypes as well as serum and stool rotavirus IgA levels were measured. Vaccination was safe and did not induce elevation of liver enzymes. None of the 12 volunteers receiving WC3 vaccine shed detectable amounts of virus although antibody rises were detected in 11 of 12 vaccines. Nine developed and increase in WC3 neutralizing antibody, one additional subject had a rise in Wa (human serotype 1) neutralizing antibody while another subject only developed a rise in stool rotavirus IgA. All of the vaccine recipients with a rise in WC3 neutralizing antibody also developed a rise in neutralizing antibody against at least one of the four most common human rotavirus serotypes. A stool IgA rotavirus antibody response was detected in 6 of 9 WC3 recipients with measurable stool antibody. None of the control subjects developed significant rises in any of the antibody titers measured. WC3 rotavirus vaccine appears to be safe and induces systemic and local immune responses in adults suggesting that further evaluation of WC3 should be considered in infants.

A model of salicylate intoxication was developed in ferrets to permit the evaluation of the interaction with viruses isolated from patients with Reye's syndrome. Salicylate intoxication produced a mild elevation of the serum glutamic oxaloacetic transaminase and fatty changes in the liver, but these changes differed from those seen in Reye's syndrome on light and electron microscopy. Salicylates were associated with decreased activity of hepatic phosphorylase and a slight depression of activity or ornithine transcarbamylase, a mitochondrial urea cycle enzyme. Infection with influenza viruses produced mild fatty changes in the liver, but did not significantly potentiate the effects of salicylate intoxication on the over-all mortality, the degree of fatty changes, or the hepatic enzymes. Influenza infection alone was not associated with decreased hepatic phosphorylase activity, but was associated with decreased activity of ornithine transcarbamylase. Influenza A was isolated from the livers of two of four animals cultured in embryonated eggs.

Effects of preinoculation rotavirus antibody titers on the probability of infection and illness were evaluated in adults challenged orally with different doses of a virulent human rotavirus (CJN strain). Preinoculation titers considered were serum neutralizing antibody, serum rotavirus IgA, serum rotavirus IgG, jejunal neutralizing antibody, jejunal rotavirus IgA, and stool rotavirus IgA. Doses of virus of either 9 x 10(1) or 9 x 10(3) focus-forming units were administered to 19 subjects each. Twenty-six were infected; 15 experienced illness. The probability of either outcome was unrelated to dose. Stool rotavirus IgA titers could not be correlated to either infection or illness, but the mean titers of the other five antibodies were significantly or nearly significantly lower in subjects infected or ill, when compared with those negative for either outcome. When analyzed by stepwise logistic regression, only serum rotavirus IgG remained significantly (P = .005) related to the probability of infection, and only jejunal neutralizing antibody remained significantly (P = .01) related to the probability of illness.

Fifty-eight children with Reye's syndrome (RS) confirmed by liver biopsy were treated at the University of Cincinnati between 1963 and 1974. Cases were clustered in the winter and spring with the peak in February and March. These coincided with the occurrence of influenza and, numerically, were associated more closely with influenza B than with influenza A. Six of the 58 cases were associated with chickenpox. Twenty-six children with RS were seen from 1963 to 1971, before the beginning of a systematic epidemiologic and virologic study. Viral infection was documented in either the patient or a contact in only 19% of those studied. Between 1971 and 1973, after the study was initiated, 16 cases of RS were diagnosed and viral infection was confirmed in 56% of these. In 1974, an epidemic of RS occurred during an influenza B epidemic and viral infection was found in either the patient or a contact in 81% of 16 cases. This study demonstrates that an association with viral infection can be proven in the majority of cases of RS when an intensive investigation is undertaken. During this study no significant environmental toxic exposures could be idenified. Most children had taken aspirin and other medications, and seven children had a history of excessive aspirin ingestion.

Herpesvirus hominis (HVH) type 2 meningoencephalitis, confirmed by isolation of the virus from cerebrospinal fluid and brain biopsy specimens, is described in a 44 year old man following renal transplantation. An HVH type 2 genital infection developed two weeks after renal transplantation, which was followed by meningoencephalitis 10 days later. Subsequently an intracerebral hemorrhage developed with evidence of diffuse vasculitis on arteriography. In a second transplant patient a similar clinical syndrome also developed after an HVH type 2 genital infection, but viral studies were not made to confirm the etiology of the meningoencephalitis. HVH has been recognized as a cause ot mucocutaneous diseases in recipients of renal transplants, but involvement of the central nervous system has not been reported.

A prospective study of 15 patients who received renal transplants defined the effect of renal transplantation on the cellular immune response to cytomegalovirus infection. Of 15 patients, 14 developed cytomegalovirus infection, usually in the first 2 months after transplantation, and all infections were accompanied by a normal humoral immune response. After the initiation of immunosuppressive therapy and transplantation, there was a general depression of lymphocyte transformation, as reflected in the response to phytohemagglutinin, accompanied by a specific defect in cellular immunity, as indicated by lymphocyte transformation to cytomegalovirus antigen. Eleven patients had cellular immunity to cytomegalovirus before transplantation, and all of these became negative in the first month after transplantation. In subsequent months, only 6 of the 14 study patients with cytomegalovirus infection developed specific cellular immune responses to cytomegalovirus. This occurred most often in patients who had severe febrile illnesses in association with infection. The specific cellular immune response which developed in the posttransplant period did not persist in three of the patients. This study demonstrates the dissociation of the humoral and cellular immune response to cytomegalovirus infection in renal transplant patients and indicates the importance of the loss of cellular immunity in the appearance of infection. Previously infected patients lost their cell-mediated immunity and had reactivation infections despite the presence of serum antibody.

In a series of clinical studies of a combined measles (Schwarz strain), mumps (Jeryl Lynn strain), and rubella (Cendehill strain) vaccine, 1,481 children received the vaccine or a placebo. The vaccine did not cause any significant reactions. The frequencies of mild, transient fever or rash or both in triple-susceptible vaccinees were similar to those that follow use of Schwarz strain measles vaccine alone. Measles, mumps, and rubella seroconversion rates in triple-susceptible vaccinees ranged from 95% to 100%. Geometric mean antibody titers were as high as those that usually result from use of these same virus strains as monovalent vaccines.

Angiolymphoid hyperplasia with eosinophilia (AHE) is classically characterized by benign vascular tumors on the head and neck of young adults. An unusual case of widespread cutaneous AHE that clinically mimicked prurigo nodularis is presented and illustrated. The relationship of AHE to the recently described entity, histiocytoid hemangioma, is discussed.