Rubella vaccination: persistence of antibodies for up to 16 years.

Sera from 123 volunteers vaccinated six to 16 years previously with one of four rubella vaccines (Cendehill, RA27/3, HPV77-DE5, and To-336) were tested for rubella antibodies by single radial haemolysis and radioimmunoassay. By radioimmunoassay 110 (89.4%) of the vaccinees had antibody concentrations greater than the minimum immune titre (that is, greater than 15,000 IU/1), 11 (8.9%) were seropositive but had concentrations less than or equal to 15,000 IU/1, and two (1.6%) were seronegative. Eight (6.5%) were seronegative by single radial haemolysis, of whom five had received Cendehill vaccine. Six to eight years after vaccination subjects who had received Cendehill vaccine had the lowest geometric mean titre of antibody by radioimmunoassay while the subjects who had received HPV77-DE5 vaccine had the highest. Although antibody concentrations less than or equal to 15,000 IU/1 were not detected among subjects given RA27/3 vaccine six to eight years previously, such low levels were detected in two (15.4%) vaccinated 11-16 years previously. These results emphasise the importance of long-term surveillance programmes so that vaccination policies may be reviewed.     

Rubella screening and immunisation of schoolgirls: results six to seven years after vaccination.

A long term follow-up study was carried out of girls given RA27/3 or Cendehill rubella vaccine in their 13th-14th year compared with a group of girls who had been found to be naturally immune at the age. A high proportion of the girls in all groups had persistent rubella antibody six to seven years after inclusion in the study, although some of these would have been considered to be susceptible to rubella by methods currently in use for screening for rubella antibody. Great care should be taken in interpreting the efficiency of the schoolgirl immunisation policy in the United Kingdom; women in their childbearing years who may have received vaccine but are found by a screening test to be seronegative should be retested by a more sensitive procedure before a final report is made.     

风疹减毒活疫苗主种子批毒种(松叶株)的安全性和免疫原性检测

评价兰州生物制品研究所用风疹病毒松叶株主种子批毒种制备的冻干风疹减毒活疫苗的安全性和免疫原性。采用自身对照、开放性的免疫原性临床观察试验,对100名8～10月龄筛选后符合条件的健康易感儿童,皮下接种1剂风疹减毒活疫苗,观察其免疫后的局部和全身反应并采集每个受试者免前和免后35d的血清标本,检测风疹HI抗体,计算阳转率和几何平均滴度。试验中所有受试者在系统观察期内均未观察到注射部位局部的不良反应;总的发热率为5%,且均为轻度发热;有1例在观察期内出现腹泻和咳嗽并持续5d,发生率为1%,属中度全身反应;血清风疹病毒抗体(HI)阳转率为100%,GMT为1:638.7±1.7。该疫苗与国内、外其它种类的风疹疫苗一样具有良好的安全性和免疫原性。     

Protection of mumps in children with various underlying diseases: application of a live attenuated mumps and trivalent measles-rubella-mumps (MRM) vaccines in these children

A live attenuated mumps and trivalent measles-rubella-mumps (MRM) vaccines have been applied to 887 and 148 children with various underlying diseases at the vaccine clinic of Osaka University Hospital between 1975 and 1985, respectively. Clinical reactions after mumps vaccination occurred in only 7 children (0.8%) and those after MRM vaccination in 28 children (19%), but their underlying diseases were not deteriorated by either vaccination. Clinical follow up study revealed that 2 of the 430 children immunized with mumps vaccine had contracted the disease during 7 year period and 2 of the 123 children immunized with MRM vaccine had contracted clinical mumps or rubella during 3 year period. The seroconversion rates after mumps vaccination were 70% and 61% by the hemagglutination inhibition (HI) test and neutralization (NT) test, respectively, while 94% by the fluorescent antibody to membrane antigen (FAMA) test. Those after MRM vaccination were 87% for measles, 96% for rubella by the HI test and 89% for mumps by the FAMA test. Serological follow up study revealed that antibodies elicited by mumps vaccination were sustained without substantial decline for at least 7 years. These results suggest that a live attenuated mumps and MRM vaccines are safe and effective in children with various underlying diseases.     

Age related differences in cellular immune response to vaccine induced rubella infection.

Employing the techniques of in-vitro lymphocyte transformation (LTF) and using Putnam strain of rubella virus as the antigen, the development of rubella specific cellular immune response was studied in different age groups of rubella seronegative normal subjects at various intervals after subcutaneous administration of HPV=77/DE5 live attenuated rubella vaccine. The rubella specific lymphocyte response in children ranging in age from two to twelve years was characterized by significant LTF activity at two months, followed by a gradual decrease. The response in adult subjects 18 to 35 years of age showed a slight delay initially in the appearance and the maximum LTF activity appeared to be 3--4 fold lower (P less than 0.01) than observed in the children. No difference was observed in the maximum antibody titers to rubella virus between these two groups of subjects. These observations suggest that the age related differences in the lymphoproliferative responses might be associated with adverse effects which are known to occur more frequently in adolescent and older patients than in childhood population after vaccine induced rubella infection.     

Cytokine profile after rubella vaccine inoculation: evidence of the immunosuppressive effect of vaccination

BACKGROUND AND AIM: Immunization with live virus vaccines may cause an immunosuppression with lymphopaenia, impaired cytokine production and defective lymphocyte response to mitogenes. These abnormalities were described in subjects vaccinated against measles. This study was performed to analyse the host immune response related to immunosuppression in subjects vaccinated with live attenuated rubella vaccine. METHODS: Eighteen schoolgirls, aged 11-13 years, were vaccinated with live attenuated rubella vaccine Rudivax. Before immunization, and 7 and 30 days after, peripheral blood was collected. Cellular fractions were subjected to flow cytometric analysis, and the lymphocyte response to phytohaemagglutinin was investigated. Plasma samples were analysed for cytokines (interleukin (IL)-4, IL-10, tumour necrosis factor-alpha, and interferon-gamma) by enzyme-linked immunosorbent assay techniques. RESULTS: On day 7 after vaccination, the number of each lymphocyte subset was decreased; however, only for CD3 and CD4 lymphocytes has a significant reduction been shown. On the contrary, tumour necrosis factor-alpha and IL-10 levels markedly increased and amounted to its maximum on day 30. Simultaneously, a significant reduction in plasma interferon-gamma and a profound decrease of the lymphocyte response to phytohaemagglutinin were shown. The changes were accompanied with marked elevation of plasma IL-4. CONCLUSIONS: Our data indicate that the vaccination with live attenuated rubella vaccine results in moderate but sustained immune disturbance. The signs of immunosuppression, including defective lymphocyte response to mitogene and impaired cytokine production, may persist for at least 1 month after vaccination.     

Neutralizing response of rabbits to an experimental rubella subunit vaccine made from immunostimulating complexes

The purpose of this study was to evaluate experimentally the immunogenicity in rabbits of rubella subunits adsorbed to the adjuvant Quil A. The adsorbed viral proteins form structurally defined ImmunoStimulating COMplexes (ISCOMs). Rubella ISCOMs were tested for their capacity to induce neutralizing and hemagglutination-inhibiting antibodies, in comparison with a commercial live attenuated vaccine. Rubella ISCOMs were as efficient as the live vaccine in inducing neutralizing and hemagglutination inhibiting antibodies, suggesting the possibility of developing an ISCOMs subunit vaccine.     

New Japanese Rubella Vaccine: Comparative Trials

A total of 142 seronegative volunteers were given one of the following rubella vaccines: Cendehill, HPV77. DE-5, RA27/3, or a new Japanese vaccine, To-336. To-336 vaccine produced a slightly higher geometric mean antibody titre (G.M.T.) (65·7) than did the HPV77. DE-5 (63·1) or RA27/3 vaccine (61·9) but the G.M.T. induced by Cendehill vaccine was much lower (39·3).Reactions, particularly joint symptoms, occurred least commonly after vaccination with To-336 vaccine. Joint symptoms occurred within seven days of menstruation in 30 out of 37 (81%) vaccines (P <0·01); their incidence was not related to oral contraception.Though there is evidence to suggest that Japanese virus strains may be non-teratogenic further data on the incidence of congenitally acquired infection in Japan must be collected before this conclusion can be supported on epidemiological grounds.     

Field trial of a live streptomycin dependent Pasteurella multocida serotype A:12 vaccine in rabbits

A live, streptomycin dependent, Pasteurella multocida (SDPM) serotype A:12 vaccine was evaluated for preventing pasteurellosis in two commercial rabbitries. Rabbits were inoculated intranasally at 5 weeks old with either 0.25 ml of vaccine containing 10(8) colony forming units/ml or 0.25 ml of diluent (control). A proportion of rabbits received a second intranasal inoculation 1 month later. Partial protection against P. multocida infection was observed 1 and 2 months after inoculation in rabbits given only one dose of vaccine. The incidence of clinical signs of pasteurellosis was similar in vaccinated and nonvaccinated market-age rabbits inoculated 4 to 6 weeks previously. In does maintained in the breeding colony, P. multocida infection and upper respiratory disease occurred more frequently in vaccinated than nonvaccinated rabbits. Humoral antibody responses (IgA, IgM, IgG) followed longitudinally were similar in vaccinated and nonvaccinated does. Hence, the SDPM vaccine was not efficacious in controlling P. multocida infection at these two rabbitries.     

The measles epidemic in Calgary 1969-70: the protective effect of vaccination for the individual and the community

Twenty per cent of the city''s population of 375,000 had had live measles vaccination as pre-school children in the preceding four years. Protection rates for killed-live vaccine schedule (Edmonston) and live vaccine only (Schwarz) were approximately 66%, not diminishing in four years; the rates for killed vaccine only (three doses) were similar for 18 months, diminishing later. As the numbers who have acquired immunity by contracting the disease fall by 10 percentage points, numbers immunized by live vaccines must rise by 15 percentage points to maintain an equivalent balance of immune and susceptible subjects.     

Vaccination of School Children With Live Mumps Virus Vaccine

Live, attenuated mumps virus vaccine (Mumpsvax) was administered to 146 school children 6 to 9 years of age. One child developed clinical mumps nine days after vaccination; epidemiological and serological data strongly suggest that this child had become infected before vaccination. Apart from this single instance there were no apparent clinical reactions that could be ascribed to the administration of the vaccine. Sixty-three of the 146 children with no clinical history of mumps had an initial serum neutralizing antibody titre of less than 1:2. Specific antibodies to mumps virus were detected in 93.5% of the sera of the susceptible children 28 days after vaccination, and the geometric mean antibody titre of these sera was low (1:6). Of the 80 initially seropositive children 21 (26.2%) showed a significant antibody response to the vaccine and this was influenced by the pre-existing antibody level. These data have further demonstrated the safety and efficacy of the live mumps vaccine in children.     

Viremia in a Recipient of HPV-77 Rubella Virus Vaccine

A live rubella virus vaccine, HPV-77 (High Passage Virus - 77 tissue culture passages) was administered subcutaneously to eight rubella-susceptible children housed in an isolation ward. One blood specimen, taken on the tenth day after vaccination, from one of the eight vaccines, yielded a rubella virus. This virus had laboratory markers which were “vaccine-like.” To our knowledge, this represents the first isolation of rubella virus from the blood of a recipient of HPV-77 vaccine. However, the consistent antibody responses among vaccinees and the regular presence of rubella virus in their pharynges argue that viremia occurs in almost every susceptible recipient. The most logical explanation for the failure to document viremia in other recipients of HPV-77 vaccine is that the viremia is ordinarily low grade or transient or both.     

A single dose of the DENV-1 candidate vaccine rDEN1Δ30 is strongly immunogenic and induces resistance to a second dose in a randomized trial

Dengue is an emerging infectious disease that has become the most important arboviral infection worldwide. There are four serotypes of dengue virus, DENV-1, DENV-2, DENV-3, and DENV-4, each capable of causing the full spectrum of disease. rDEN1Δ30 is a live attenuated investigational vaccine for the prevention of DENV-1 illness and is also a component of an investigational tetravalent DENV vaccine currently in Phase I evaluation. A single subcutaneous dose of rDEN1Δ30 was previously shown to be safe and immunogenic in healthy adults. In the current randomized placebo-controlled trial, 60 healthy flavivirus-naive adults were randomized to receive 2 doses of rDEN1Δ30 (N = 50) or placebo (N = 10), either on study days 0 and 120 (cohort 1) or 0 and 180 (cohort 2). We sought to evaluate the safety and immunogenicity of this candidate vaccine in 50 additional vaccinees and to test whether the humoral immune response could be boosted by a second dose administered 4 or 6 months after the first dose. The first dose of vaccine was well tolerated, infected 47/50 vaccinees and induced seroconversion in 46/50 vaccinees. Irrespective of dosing interval, the second dose of vaccine was also well tolerated but did not induce any detectable viremia or ≥4-fold rise in serum neutralizing antibody titer.Only five subjects had an anamnestic antibody response detectable by ELISA following a second dose of vaccine, demonstrating that the vaccine induced sterilizing humoral immunity in most vaccinees for at least six months following primary vaccination.The promising safety and immunogenicity profile of this vaccine confirms its suitability for inclusion in a tetravalent dengue vaccine.     

Compliance with diphtheria,tetanus, and pertussis immunisation in Bangladesh: factors identifying high risk groups.

OBJECTIVE--To evaluate factors associated with non-compliance with having second vaccination against diphtheria, tetanus, and pertussis in a treatment centre in Dhaka to determine which children were most at risk of not completing immunisation. DESIGN--Cohort study of infants given first dose of the vaccine and followed up six weeks later to ascertain compliance with having second dose. Factors associated with non-compliance were evaluated. SETTING--Dhaka treatment centre of the International Centre for Diarrhoeal Disease Research, Bangladesh. SUBJECTS--136 unimmunised children aged 6 weeks to 23 months who lived within reach of the treatment centre. At time of the six week follow up 16 of the children could not be traced and seven had died. INTERVENTIONS--All children received their first dose of the vaccine. In each case health education workers had informed the mother about the value of immunisation, and she was given clear instructions to bring the child back after four weeks for the second dose. MAIN OUTCOME MEASURE--Rate of non-compliance with advice to return child for second vaccination. RESULTS--46 of 113 children (41%) received the second dose of the vaccine. Factors most closely associated with mothers'' failure to comply with the second dose were lack of education and low income. Children whose mothers knew most about immunisation at first interview were more likely to have their second dose. CONCLUSIONS--Preventive health care services such as immunisation are appropriately offered in treatment centres, but compliance among children varies with socioeconomic status and mother''s education. Further research should be aimed at ways to make health education more effective among uneducated parents.     

Studies on live rubella vaccine. V. Quantitative aspects of interference between rubella, measles and mumps viruses in their trivalent vaccine

Rubella vaccine combined with measles and mumps vaccines was administered in a single injection to children of 1 to 5 years of age. All three vaccines were serologically effective, and the clinical reactions caused by measles vaccine were considerably alleviated, when 6 x 10(3) PFU of rubella and 10(4) TCD50 per dose of mumps vaccines were combined with 5 x 10(4) TCD50 of measles vaccine. When a larger amount of mumps vaccine (3 x 10(5) TCD50/dose) was used, it caused interference with the rubella and measles viruses, i.e., the antibody response to rubella virus became poor and the incidence of clinical reactions to measles virus decreased. On the other hand, when 5 x 10(5) TCD50/dose of measles vaccine was combined with 10(4) TCD50/dose of mumps vaccine, the clinical reactions to measles virus were decreased but were almost the same as those induced by this vaccine alone.     

Rubella Vaccine Trial in Children

A study with RA 27/3 attenuated rubella virus vaccine (Plotkin strain) showed that this produced a significant antibody response in all of twenty-one vaccinated non-immune children without any appreciable marked clinical reactions. Serological examination of 53 non-immune and 29 immune siblings living in the same households failed to show any evidence of transmission of infection.     

Antibody response in school children to live rubella vaccine (Cendehill strain)

The efficacy of an attenuated rubella virus vaccine, Cendevax, was tested on 65 school children. Forty-nine of them (75%) had pre-existing antibodies and in these there was no increase in the HAI antibody titres after administration of the vaccine. Sixteen children (25%) had no demonstrable rubella HAI antibody prior to vaccination. From the latter group, postvaccination serum samples were available from only 11, and 10 of these seronegative children showed seroconversion after vaccination. The geometric mean HAI titre was 1:180. Seven of the 10 postvaccination serum samples had complement-fixing antibodies and specific IgM antibodies were detected by the immunofluorescence test in 8. No correlation was observed between the CF and the IgM antibodies.     

Reduced secretory antibody response to live attenuated measles and poliovirus vaccines in malnourished children.

Serum and nasopharyngeal IgA antibody levels were estimated in 20 malnourished children and 20 matched healthy controls after immunization with a single dose of live attenuated measles or poliovirus vaccine. Seroconversion and serum neutralizing antibody titres were comparable in the two groups. Secretory IgA antibody was detected significantly less often in undernourished children; the time of its first appearance was delayed-and its maximum level was significantly lower. Impaired secretory antibody response in malnourished children may contribute to slow inadequate recovery from viral and enterobacterial infections and predispose to lifethreatening complications.     

Factors affecting uptake of measles,mumps, and rubella immunisation.

OBJECTIVE--To study factors affecting uptake of measles, mumps, and rubella immunisation. DESIGN--Cohort study using data from computerised child health systems. SETTING--10 health districts in North East Thames and North West Thames regions. SUBJECTS--7841 children born in January to March 1990 and resident in the districts up till the end of October 1991. MAIN OUTCOME MEASURES--Overall uptake of measles, mumps, and rubella immunisation, variation of uptake among groups of children, and odds ratio of being vaccinated against measles, mumps, and rubella. RESULTS--The overall uptake rate of measles, mumps, and rubella immunisation for the study cohort in the 10 districts was 82%. Wide variation was identified among children with different demographic characteristics. Lower uptake was associated with absent or incomplete primary immunisation, including omission of pertussis vaccine. Other factors affecting uptake included the type of resident district, birth order, where registered for immunisation (general practitioner or clinic), and one parent family status. CONCLUSIONS--Many districts have difficulties in meeting the 90% target for measles, mumps, and rubella immunisation, mainly because of the characteristics of their local population. To increase overall coverage, the health service should target families with adverse factors, especially those whose children have missed previous immunisations.     

No evidence of murine leukemia virus-related viruses in live attenuated human vaccines

Background

The association of xenotropic murine leukemia virus (MLV)-related virus (XMRV) in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. Nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of XMRV and MLV into human populations. To address this possibility, we tested eight live attenuated human vaccines using generic PCR for XMRV and MLV sequences. Viral metagenomics using deep sequencing was also done to identify the possibility of other adventitious agents.

Results

All eight live attenuated vaccines, including Japanese encephalitis virus (JEV) (SA-14-14-2), varicella (Varivax), measles, mumps, and rubella (MMR-II), measles (Attenuvax), rubella (Meruvax-II), rotavirus (Rotateq and Rotarix), and yellow fever virus were negative for XMRV and highly related MLV sequences. However, residual hamster DNA, but not RNA, containing novel endogenous gammaretrovirus sequences was detected in the JEV vaccine using PCR. Metagenomics analysis did not detect any adventitious viral sequences of public health concern. Intracisternal A particle sequences closest to those present in Syrian hamsters and not mice were also detected in the JEV SA-14-14-2 vaccine. Combined, these results are consistent with the production of the JEV vaccine in Syrian hamster cells.

Conclusions

We found no evidence of XMRV and MLV in eight live attenuated human vaccines further supporting the safety of these vaccines. Our findings suggest that vaccines are an unlikely source of XMRV and MLV exposure in humans and are consistent with the mounting evidence on the absence of these viruses in humans.