Showing papers on "Vaccination published in 1972"

Immunity in Shigellosis. II. Protection Induced by Oral Live Vaccine or Primary Infection

Abstract: Two attenuated strains of Shigella flexneri 2a, a Shigella-E. coli hybrid, and a streptomycin-dependent mutant, were safely given to adult male volunteers. When vaccinated individuals ingested virulent S. flexneri 2a, clinical disease and fecal excretion of virulent organisms occurred with less frequency than in unvaccinated volunteers. The level of immunity resembled that seen after recovery from active infection. These studies have given some indication that bacillary dysentery may be controlled by an oral live vaccine, and field trials designed to quantitate induced immunity are planned for the near future.

Oral polio vaccination of children in the tropics: i. the poor seroconversion rates and the absence of viral interference

Abstract: A study of the efficacy of trivalent oral polio vaccine (OPV) was conducted in a group of children between the ages of 3 months and 6 years, in Vellore, Tamil Nadu. Of the 191 children given the 1st dose of OPV, 72, 93 and 94 were found to be seronegative to poliovirus types 1, 2 and 3, respectively, prior to vaccination. The seroconversion rates in them were 35% to type 1, 76% to type 2 and 48% to type 3 following 2 doses 8 weeks apart. Among the 40 triple seronegative children, the seroconversion rates after 2 doses were 28% to type 1, 77% to type 2 and 40% to type 3. These rates are very poor, especially when compared to seroconversion rates in children in temperate climates. Loss of potency of the vaccine, interference of enteric viruses prevalent at the time with vaccine viruses and interference among the 3 vaccine virus types have been excluded as the cause of the poor serologic response observed in these children. Results of this and other similar studies should be taken into account when formulating dosage schedules of OPV in the tropics.

A Prospective Study of Serum Antibody and Protection Against Smallpox

Abstract: In order to prospectively evaluate the relation between serum antibody and protection against smallpox, blood was drawn from 146 contacts of Pakistani smallpox cases before the end of the usual incubation period. Most were well vaccinated, and after follow-up only three cases of secondary smallpox appeared. Hemagglutination inhibition antibody titers proved to have virtually no predictive value for assessing susceptibility against smallpox, since most contacts, despite their protection, had undetectable antibodies. Neutralizing antibodies were present in high titer in most contacts and no contacts with a titer of 1:32 or higher developed smallpox. Two of the cases, however, did have detectable neutralizing antibody at the time of exposure and some persons with no detectable neutralizing antibody were spared. The role of humoral antibody in protection against pox-viruses is still unclear.

Immunity in Experimental Salmonellosis III. Comparative Immunization with Viable and Heat-Inactivated Cells of Salmonella typhimurium

Abstract: Vaccination with viable cells of an avirulent Salmonella typhimurium galE mutant provides mice with solid specific immunity against subsequent infection with a virulent smooth strain. Such a live vaccine is markedly more potent than one prepared from inactivated cells of the virulent smooth strain. The superiority of the live vaccine is particularly well demonstrated when the oral route of application is used. The protective capacity of the galE mutant is based on its ability to synthesize complete smooth-like cell wall lipopolysaccharide in vivo.

Isolation of attenuated rubella-vaccine virus from human products of conception and uterine cervix.

Abstract: To evaluate the fetal hazard of accidental administration of live rubella vaccine during pregnancy, the vaccine was given to 35 women certified for legal abortion. Twenty-four of these were rubella seronegative. Various specimens, including the products of conception, were tested for rubella virus independently in three collaborating laboratories. Rubella virus was recovered from the placenta in six cases and from the fetus in one case. Virus was also found in 13 of 22 uterine cervical swabs taken nine to 25 days after vaccination of seronegative mothers. Virus was not isolated from comparable specimens obtained from women with pre-existing antibody. The results indicate a hazard of placental and fetal invasion by the vaccine virus and emphasize the need to observe precautions when post-puberal female patients are vaccinated.

Efficacy of pertussis vaccines: a brighter horizon.

Abstract: A study of pertussis infections in 186 children under 11 years of age in the Manchester region during 1969-71 suggests that recently-manufactured vaccines have been more effective than those made before 1967. The earlier vaccines were effective mainly against the serotypes of Bordetella pertussis possessing antigen 2, while those made from 1967 are more nearly equal in their effectiveness against thedi fferent serotypes. A booster dose of the earlier vaccines did not prevent infection with type 1,3 organisms, but we obtained a positive culture from only one child who had received four doses of recent vaccine. Simultaneous infection of a child with two or more serotypes was frequently seen. The predominant serotype in a patient was usually type 1,3; less often it was type 1,2,3 or type 1,2; it was never type 1. A change of serotype sometimes occurs during the course of the illness and is probably directed by the vaccination status of the patient in relation to the serotype of the initial infection. Our findings emphasize the need for vaccines to contain adequate amounts of all three pertussis agglutinogens, and for satisfactory immunization schedules to be used in their administration.

Routine administration of oral polio vaccine in a subtropical area. Factors possibly influencing sero-conversion rates.

Abstract: Poliomyelitis is an important problem of public health in warm-climate countries. Studies of serological responses to vaccination in these countries have given conflicting results but in many investigations the rates have been considerably less than in countries with temperate climates. In this study three possible factors influencing sero-conversion were investigated - the season of the year when vaccine was given, the social status of the mother (as indicated by the number of years of schooling) and the presence of non-poliomyelitis viruses (NPV) in the gut when vaccine was given.Over 200 children about 2 months of age were included in the study. Each was given three doses of trivalent vaccine at 6-week intervals.The sero-conversion rates of the groups fed in winter were excellent but were slightly less good in summer. The differences were greatest in children in the lower socio-economic groups and in children excreting other enteroviruses.The conclusions are that, provided a potent vaccine is used, the factors which diminish the effectiveness of immunization in warm-climate countries can be overcome: (1) by giving three doses of trivalent vaccine; (2) by beginning vaccination at the earliest possible age (when enteroviruses are fewest); (3) by concentrating special attention on the lower socio-economic groups and if necessary by giving a reinforcing dose several months after the third dose has been given - preferably in the colder months.

Antigenic competition and nonspecific immunity after a rickettsial infection in mice: restoration of antibacterial immunity by phenyl-imidothiazole treatment.

Abstract: A prior Coxiella burneti infection renders mice nonspecifically resistant to a Brucella abortus challenge but depresses the specific activities of either dead vaccine (in incomplete adjuvant) or of live Brucella vaccine and inhibits Brucella antibody formation that usually follows the use of live vaccine Thus, a first antigenic stimulus interferes with responses to a second unrelated antigen to cover both nonspecific immunity and antigenic competition Phenylimidothiazole treatment 2 days after anti-Brucella vaccinations restores most of the specific activities of these vaccines which were reduced by C burneti priming, but leaves as impaired as they were Brucella antibodies titrated through three serologic tests This finding suggests that phenylimidothiazole stimulates above all cell-mediated immunity

Prevalence of antibody to current influenza viruses and effect of vaccination on antibody response.

Abstract: The extent of antibody to the influenza virus A/Hong Kong/68 (H3N2) after four years of prevalence was investigated in Britain and in the U.S.A. The results indicated a high incidence in both populations. The prevalence of antibody to a variant A/England/42/72 (H3N2) which has been causing epidemics of influenza in the southern hemisphere during the middle months of 1972 was also investigated. The differences reflect the shift in antigenic content of this variant, and although the overall proportion of the sera with antibody at > 1/40 was 37%, some age groups had an incidence of only 20% or less with antibody at this level. A commercial inactivated A/Hong Kong/68 influenza vaccine was given to a group of volunteers in Britain to see how effective it might be in stimulating antibody to the variant A/England/42/72. The antibody responses were better than expected from earlier vaccine studies, and 63% of the vaccinees developed antibody to the A/England/42/72 to levels thought likely to be protective. This suggested that until a vaccine made with the variant A/England/42/72 becomes available the present A/Hong Kong/68 vaccine would be of use to protect those at special risk this winter.

Vaccination against Marek's disease with cell-free turkey herpesvirus: interference by maternal antibody.

Abstract: An apparently nonpathogenic herpesvirus of turkeys (HVT) (12) is considered safe and efficacious (8) to use as a vaccine for the protection of chickens against Marek's disease (MD). Most studies reported used cell-associated virus stored at -196 C with dimethyl sulfoxide as a preservative, and this type of vaccine is presently in use in many countries. Cell-free HVT also was shown effective (8), though its use was not considered practical until suitable methods for virus extraction and lyophilization were developed (2). Lyophilized vaccine is now being produced in Great Britain. In an earlier communication (9), we reported that chicks with maternal antibody against Marek's disease virus (MDV) were fully susceptible to cell-free HVT even though the two viruses are antigenically related (12). However, many chicks with homologous maternal antibody (from HVT-vaccinated dams) were resistant to vaccination at 1 day of age. A few chicks were still resistant at 2 weeks, but by 3 weeks of age all were fully susceptible to vaccination. Since HVT vaccine is generally applied soon after hatching, and since many breeding flocks have themselves been vaccinated with HVT, interference be maternal antibody is an important question. In our earlier study (9), the immune parent flock was vaccinated after the dams had reached sexual maturity (91/2 months old) and only one month prior to obtaining progeny for the experiments. It was considered possible that maternal antibody levels (and the vaccination interference problem) might be less, or even absent, if elapsed time after vaccination was longer or if the dams were vaccinated at 1 day old rather than at an older age. Also of interest was the question whether HVT maternal antibody could

Influenza Immunization: Field Trial on a University Campus

Abstract: The purpose of this field trial on influenza vaccine, which was done with a population of university students, was to compare the aerosol route with the subcutaneous route of vaccine administration and the Hong Kong influenza vaccine with the older A2 influenza vaccine ("bivalent" vaccine). Side-effects of the vaccines were significantly higher in the groups that received the vaccine subcutaneously. There were no more side-effects in those who received vaccine by aerosol. There was a significant reduction in the rate of illness in all groups vaccinated except for the group given bivalent vaccine subcutaneously. Recipents of Hong Kong vaccine had significantly greater protection than did recipients of the bivalent vaccine. Recipients of aerosol vaccine had significantly better protection than did those who received vaccine by the subcutaneous route. The data suggest that protection was closely related to the ability of the vaccine to stimulate nasalsecretion antibody to the A2 Hong Kong influenza virus.

Further Characterization of the Local Respiratory Tract Antibody Response Induced by Intranasal Instillation of Inactivated Rhinovirus 13 Vaccine

Abstract: The nasal secretory antibody response of volunteers vaccinated intranasally with an inactivated rhinovirus type 13 vaccine was further characterized. It appeared that intranasal vaccination induced resistance to challenge which lasted at least 6 months. The local neutralizing antibody which developed was specific for type 13 virus and this antibody persisted for at least 330 days following vaccination. Finally, there was a suggestion that the local respiratory tract secretory immune response possesses some degree of immunologic memory.

Antibody responses and resistance to challenge in volunteers vaccinated with live attenuated, detergent split and oil adjuvant A2/Hong Kong/68 (H3N2) influenza vaccines: A report to the Medical Research Council Committee on Influenza and other Respiratory Virus Vaccines

Abstract: Forty-nine subjects were vaccinated with either live attenuated, detergent split, or oil adjuvant A2/Hong Kong influenza vaccines, or a saline influenza B vaccine as control. Respiratory symptoms occurred more frequently in subjects who received the live vaccine but in total there was little difference between the symptoms in the four groups. Antibody titres in nasal washings and serum were measured by haemagglutination inhibition, neuraminidase inhibition and virus neutralization tests. The oil adjuvant vaccine stimulated larger antibody responses than the other procedures. Six weeks after vaccination the volunteers were challenged with partially attenuated live A2/Hong Kong influenza virus administered intranasally. The live attenuated and oil adjuvant vaccines provided the best protection against challenge.

Attenuated Marek's disease herpesvirus: protection conferred on strains of chickens varying in genetic resistance.

Abstract: Five strains of chickens differing in susceptibility to Marek's disease (MD) were vaccinated with the attenuated BC-1 isolate of MD herpesvirus and were subsequently challenged with virulent virus. Significant protection was conferred to all strains. However, when vaccination was at 1 or 2 days there were significant differences among strains in the incidence of gross lesions of MD. The ranking of strains for susceptibility to MD was not usually altered by vaccination. By comparison, differences in the susceptibility of strains was not observed among chickens vaccinated at 23 days and these were better protected than those vaccinated at 2 days. Vaccination at both 2 and 23 days showed no significant advantage over a single vaccination at 23 days.

Neurological disease in man following administration of suckling mouse brain antirabies vaccine.

Abstract: In Latin America, suckling mouse brain (SMB) vaccine has become the most commonly used vaccine for immunization of both man and animals against rabies. This vaccine is highly immunogenic, is relatively economical and easy to produce, and is believed to be free of the immunoencephalitogenic factor. From 1964 to the end of 1969, there were 40 reported cases of neurological disease following administration of SMB vaccine, 32 of which met the criteria for inclusion in this report. These 32 cases occurred in 8 different countries. In contrast to neurological disease following the administration of other types of nervous tissue vaccine, the majority of the cases following vaccination with SMB vaccine had a Guillain—Barre-type syndrome with peripheral nervous system involvement and a higher case—fatality rate. The causative agent has not been demonstrated. Modifications in the production and handling of the vaccine may be producing changes that are responsible.

Experimental Infection of Horses with an Attenuated Venezuelan Equine Encephalomyelitis Vaccine (Strain TC-83)

Abstract: Ten horses (Equus caballus) were vaccinated with strain TC-83 Venezuelan equine encephalomyelitis (VEE) virus vaccine. Febrile responses and leukopenia due to a reduction of lymphocytes and neutrophils were observed in all animals. Viremias were demonstrable in eight horses, with a maximum of 10(3.5) median tissue culture infectious dose units per ml of serum in two horses. Clinical illness with depression and anorexia were observed in five horses. Neutralizing (N), hemagglutination-inhibiting, and complement-fixing antibodies to the vaccine virus were demonstrable by 5, 6.5, and 7 days, respectively, after vaccination. Differential titrations of serum to six VEE strains revealed high titers of N antibody to vaccine virus, moderate titers to the epizootic Trinidad donkey no. 1 strain (VEE antigenic subtype I, variant A) from which TC-83 was derived, and low titers to two other epizootic strains (subtype I, variants B and C) in all horses at 1 month after vaccination; some animals responded with low levels of N antibody to the enzootic viruses (subtype I, variants D and E). Fourteen months after vaccination, six animals with detectable N antibody were challenged with MF-8 (subtype I, variant B), an epidemic-epizootic strain isolated in 1969 from a man in Honduras. All horses resisted challenge with the equine pathogenic strain of VEE. Marked increases of N antibody in most horses were demonstrable to some VEE strains when tested 1 month after challenge.

Field trial with human and equine influenza vaccines in children: protection and antibody titres.

Abstract: A placebo-controlled influenza vaccination trial was carried out on 374 children in the winter of 1967-68. The children were randomly vaccinated with 300 CCA of A2/England/1/1966, 300 CCA of A/equine 2/Miami/1963, or with a placebo. During this winter an influenza outbreak occurred, caused by A2/Nederland/1968. The A2 vaccine yielded a protection rate of 58% (P = 0.02) and the A/equine 2 vaccine a rate of 19% (P = 0.33). Serological data revealed that all influenza infections occurred in subjects who had a pre-epidemic haemagglutination inhibition titre below 150. The antibody response against various human influenza A2 viruses and against the horse strain (A/equine 2) is discussed.

Effect of Adjuvant on Immunogenicity of a Heat-Killed Salmonella Vaccine

Abstract: Specific-pathogen-free C57B1 mice were vaccinated with one or two doses of 20 [tg of heat-killed Salmonella enteritidis suspended in saline or in Freund's complete adjuvant. The saline-suspended vaccine did not protect against a subsequent oral challenge by a highly virulent strain of S. enteritidis (5694) but did increase resistance to a sublethal challenge with a partially attenuated strain (Se 795). Two doses of 20 tg of dead cells suspended in Freund's complete adjuvant sensitized the host so that an accelerated immune response could be demonstrated in mice infected orally with S. enteritidis 5694. This response was dose dependent. The highest dose of 500 itg of dead cells in adjuvant induced an immune response equivalent to that seen in actively infected mice. The significance of these findings in relation to immunity to typhoid was evaluated.

Influence of age on clinical response to HPV-77 duck rubella vaccine.

Abstract: The involvement of the joints that may follow immunization with live rubella virus vaccines is strongly age-related. The present policy of extending vaccination to postpubescent girls and adult women requires precise definition of the reactions likely to be encountered by physicians in routine use of the vaccine. Six hundred fifty-three females, eight months to 41 years of age, who were initially without rubella antibody were given duck cell attenuated HPV-77 rubella virus vaccine. Reactions in the joints (arthritis or arthralgia or both) were not seen in children under 12 years of age, were seen infrequently in the 12- to 25-year-old age group (7.5%), and were encountered with high frequency (58.3%) in women who were 26 to 41 years old. Reactions were transient, self-limited, of short duration, and mild in all but a few older women.

Yellow Fever Vaccination, Avian Leukosis Virus, and Cancer Risk in Man

Abstract: Comparison was made between 2659 veterans who died of cancer, during 1950 to 1954 or 1959 to 1963, and matched controls, based on the frequency of yellow fever immunization during World War II. The vaccine was produced from chick embryos that almost certainly contained avian leukosis-sarcoma viruses. Among the veterans, no relation was found between vaccination and leukemia, lymphoma, or other cancer.

Epidemic Measles in a Divided City

Abstract: Between June 1970 and January 1971, 633 cases of measles occurred in Texarkana, a city bisected by the Texas-Arkansas state line. A total of 606 (95.7%) of the cases occurred in Texarkana (Bowie County), Tex, a community that had never had a measles vaccination campaign. The level of prior immunity, natural plus vaccine-induced, in the 11,185 children aged 1 to 9 years in Bowie County was estimated to be 57%. Only 27 cases occurred in Texarkana (Miller County), Ark, where more than 95% of the 6,016 children aged 1 to 9 years were immune. Nineteen of the 27 Arkansas patients had documented exposures in Texas. Twenty-seven cases of measles occurred in previously vaccinated children. Six of these children had received vaccine with measles immune globulin prior to 1 year of age. Vaccine efficacy was calculated to be 95.9%.