MMR vaccine uptake rates: a data validation study

As part of our investigation into the decrease in the measles, mumps and rubella (MMR) vaccine uptake rates, we validated MMR vaccination records of all children born between 01/09/1998 and 31/08/1999 in our area (North Cheshire, South Cheshire, and Wirral). A significant number of children had received their MMR vaccine but were not recorded as such by the Child Health Computer System (CHCS). Reported COVER (cover of vaccination evaluated rapidly) data uptake (combined) for North Cheshire, South Cheshire, and Wirral Health Authorities for the period covered by the data validation study was 90.5%, the corrected uptake following the validation was 92.6%, 2.1% higher than the reported coverage. If the coverage data were to continue to form part of the NHS indicators of PCT performance, action by all PCTs to improve accuracy of immunisation data would be highly desirable. Electronic transfer of information from practices to the CHCS and between CHCSs, i.e. across boundaries, could improve data accuracy.

Seroprevalence survey of measles, rubella, varicella, and mumps antibodies in health care workers and evaluation of a vaccination program in a tertiary care hospital in Japan

Vaccine-preventable viral infections in health care workers (HCWs) have been on the rise for the past 10 years in Japan. To reduce the viral infections and the burden of exposure follow-up surveys at a tertiary care hospital in Osaka, Japan, a seroprevalence survey was conducted, and free vaccinations for measles, rubella, varicella, and mumps were offered to newly hired HCWs (199 physicians and 72 nurses and nursing assistants) who had negative serologic results for antibodies against these viruses. Negative antibody titers were obtained from 7.4% of the newly hired HCWs for measles, 12.5% for rubella, 4.1% for varicella, and 15.9% for mumps. The vaccination program for HCWs improved the vaccine-preventable infection rates and resulted in fewer exposure follow-up surveys, fewer lost work days, and fewer HCWs requiring hospitalization for these viral infections compared with those counted for the previous year. These data indicate that all HCWs should be strongly recommended to be vaccinated against (or have documented immunity to) these viruses in Japan, as is the case in the United States.

[Adverse effects following vaccinations and effectiveness of different live vaccines against mumps]

The paper analyses adverse effects with special emphasis on meningitis following mumps vaccination with vaccines containing different strains of mumps virus. It also provides information on the comparative effectiveness of different types of vaccines. Information is based on the review of literature and data collected in the Department of Epidemiology, National Institute of Hygiene in Warsaw. Most of the data provides evidence that risk of aseptic meningitis following vaccines containing Jeryl Lynn strains of the mumps virus is generally smaller than the risk following vaccines based on Urabe AM 9 strain. Studies on vaccine effectiveness showed moderately higher effectiveness of vaccines based on Urabe AM 9. The main aim of this paper was to provide comprehensive information on the effectiveness and safety of mumps vaccines registered in Poland for the purpose of decisions making on their use.

Evaluation of the national immunisation programme in the Netherlands: immunity to diphtheria, tetanus, poliomyelitis, measles, mumps, rubella and Haemophilus influenzae type b

The immunity to vaccine-preventable diseases included in the Dutch immunisation programme in the general population and among orthodox reformed individuals who refuse vaccination was assessed. The programme induces good protection. However, a large proportion of adults lacks diphtheria and tetanus immunity. Measles, mumps and rubella seroprevalence was somewhat lower among vaccinated compared to unvaccinated cohorts. The prevalence of HibPS antibodies declined during 2.5 years after the fourth vaccination. However, protection occurs also by memory immunity. Herd immunity is sufficient among the general population, but not among orthodox reformed individuals. Immunosurveillance is an efficient way to evaluate the effects of immunisation programmes and identify risk groups for infection.

Reactogenicity and immunogenicity of a live attenuated tetravalent measles-mumps-rubella-varicella (MMRV) vaccine

In countries where routine varicella vaccination is implemented, it is usually given at the same age as that recommended for measles-mumps-rubella (MMR) vaccination. A combined multivalent measles-mumps-rubella-varicella (MMRV) vaccine would offer the convenience of a single injection and facilitate implementation of varicella vaccination into routine childhood immunisation schedules. We evaluated the immunogenicity and reactogenicity of a tetravalent MMRV candidate vaccine compared to an extemporaneous mix of a measles-mumps-rubella vaccine and varicella vaccine (MMR/V), and to a measles-mumps-rubella (MMR) vaccine alone. A multicentre study was conducted in which a total of 240 healthy children aged 12 months (80 per group) were randomised to receive MMRV, MMR/V, or MMR alone. Active surveillance for adverse events was undertaken for 43 days post-vaccination. Blood samples were taken prior to vaccination and at 60 days post-vaccination. There were no significant differences between groups in rates of pain, redness, or swelling at the site of vaccination. There was no significant difference in the rate of any fever (axillary temperature >or=37.5 degrees C) and grade 3 fever (axillary temperature >39.0 degrees C) between the groups receiving MMRV and MMR during the 43-day follow-up period. Although, a significant increase was found for fever of any cause with onset between days 0 and 14 for MMRV compared to the MMR group, there was no significant difference in grade 3 fever rates during the same period. With respect to immunogenicity, MMRV and MMR/V demonstrated similar seroconversion rates to each component compared to MMR alone, with at least 91.9% of subjects in all groups seroconverting to each vaccine component 60 days after vaccination. Decreased GMTs for varicella antibody at day 60 indicated that there may have been inhibition of this response compared to MMR/V. This tetravalent MMRV candidate vaccine showed promising results, although further examination of the possible increase in minor fever and decreased varicella immunogenicity should be assessed in future studies.

[Mumps in Poland in 2000]

A total of 17,548 mumps cases were reported in Poland in 2000. A 5-fold decrease in incidence of the disease (from 233.4 to 45.4 per 100,000 population) was noted, when compared with 1999. Approximately 4.8% of mumps cases were hospitalized (849 cases). The majority of the reported cases were children aged 5-9 (51.4% of all cases). In all voivodships the incidence was lower than in previous years. The probable cause of the decline of mumps cases was a marked amelioration of MMR vaccination coverage among 3-year old children. The MMR vaccine is not included into the national program of immunization, the vaccination is recommended for 2-year and 7-year old children.

[The knowledge about measles, mumps and rubella among parents in the county of Roskilde]

INTRODUCTION

The aim was to determine how much knowledge parents have of MMR diseases and the side effects of the vaccine, and what influence this has on acceptance of the vaccination programme.

MATERIALS AND METHODS

Sampling three districts of Roskilde County was done by the distribution of 1867 questionnaires to the parents of children aged 0-15 years in 22 institutions and schools (1 January to 28 February 2000).

RESULTS

Of the 878 (47%) replies, 825 (94%) had followed the vaccination programme. There was no difference between those who had followed the programme and those who had not with respect to reports of complications to the diseases, but the latter group reported more complications to the vaccine. In the vaccinated group, there were significantly more who stated that the doctor's opinion of the vaccine was positive, and acceptance of the remaining vaccination programme was also greater in this group. More children in the non-vaccinated group were involved in the decision about vaccination.

DISCUSSION

Though knowledge of the diseases does not seem to influence the decision about vaccination, the responses raise the question of how information is to reach the general public. An open debate is needed on vaccination complications, as it is these or uncertainty about them that seem to influence the parents' choice. For 70% of parents, the doctor is their source of information, and it is therefore important for acceptance of the MMR vaccine that doctors have a positive view and are able to communicate this view to the parents.

An outbreak of mumps in the metropolitan area of Walsall, UK

OBJECTIVE

To describe the epidemiology of excessive mumps cases during the year 2000, within the metropolitan area of Walsall, UK; to assess the impact of the mumps outbreak on morbidity; and to inform future communicable disease control strategy.

METHODS

Demographic records, school attendance, uptake of the measles-mumps-rubella (MMR) vaccine, and mumps-associated admission to hospital, were reviewed for all Walsall residents diagnosed and notified with mumps during the year 2000.

RESULTS

There were 200 mumps notifications in 2000 (76.6 per 100,000), representing the highest incidence in England. Only 91 of the notified cases were salivary antibody positive for mumps IgM, and 32 were negative, although 77 were not tested. Since 1990, annual totals have never previously exceeded 20. Over 90% of patients were <20 years old, with a peak age group of 10-14 years; 88% attended schools located within Walsall. The pattern of spread suggested that the outbreak proceeded through schools from north to south in the more deprived western half of the metropolitan area. Most cases (136, 68%) had received one (99, 49.5%) or two (37, 18.5%) doses of MMR vaccine; cases > or =20 years old had never received MMR. Six cases (aged 4-14 years) were admitted to hospital, all with a successful outcome, including one male with meningitis and one female with pancreatitis. Current uptake of the MMR vaccine at 24 months has dropped to below 90% in recent years, as in most parts of the UK.

CONCLUSIONS

Future mumps outbreaks in schools, and among older age groups, can be predicted, since most older children and young adults have received only one dose of MMR vaccine or no vaccination at all. Primary vaccine failure is well described in mumps, and cases during outbreaks can include recipients of two MMR vaccine doses. It was fortunate that no severe morbidity was associated with this outbreak (prior to MMR, two to four mumps deaths occurred annually in England and Wales). Measures to restore the uptake of MMR to the previous levels of above 90-95% will be necessary to reduce the risk of the mumps virus circulating within communities. Older children are susceptible, and it may be advisable to ensure second-dose MMR uptake while they are still at or when they leave school, or when they enter college, university or the military.

Mumps outbreak in vaccinated children in Gipuzkoa (Basque Country), Spain

A mumps outbreak occurred in a group of vaccinated children aged 3-4 years in San Sebastián (Gipuzkoa, Basque Country, Spain) in 2000 during the same period as a revaccination campaign against measles-mumps-rubella (MMR) was performed. The clinical cases were confirmed by viral culture, detection of viral RNA and/or specific IgM. Eighty-eight percent of the children had been vaccinated with the Rubini strain and the remainder with the Jeryl-Lynn strain. The attack rate was 47.9% (35 cases in 73 school-attending children of this age). The outbreak was caused by an H genotype strain of mumps virus which was circulating at the same time as a D genotype strain that caused sporadic cases. By sequencing the small hydrophobic (SH) gene, the strains of the clinical cases were identified as wild-type mumps virus with heterologous genotypes in comparison to the vaccine strains used in our area.

[Post-transplantation vaccination of bone-marrow transplant recipients]

BACKGROUND

Patients subject to bone marrow transplantation (BMT) and other blood stem cell transplantations are severely immunocompromised after transplantation. Some studies have suggested that post-transplantation loss of acquired immunity may play a role. The objective of this study was to determine the susceptibility to vaccine-preventable diseases in people subject to BMT and the serologic response after vaccination.

PATIENTS AND METHOD

Study population was people subject to transplantation at least 6 months before initiating vaccination and without immunosuppressive treatment at that time. A prevaccination serologic analysis was carried out, and the hepatitis B, the adult tetanus-diphtheria (Td), the IPV, the influenza and the pneumococccal vaccines were administered in accordance with standard guidelines Depending on the immune status of the patient according to the serologic analysis, the MMR vaccine was administered no sooner than 18 months after transplantation. After vaccination, a serologic analysis was carried out to determine the response.

RESULTS

The mean time SD between transplant and the initiation of vaccination was 3.2 2.9 years. Of the 122 recipients of BMT (average age 35.8 13 years; 54.2% male), 51.7% received an allogenic and 48.3% an autologous transplant. Before vaccination, the susceptibility was 48.2% for tetanus, 66.7% for diphtheria, 74.1% for pertussis, 85.9% for hepatitis B, 13.4% for measles, 36.7% for rubella and 9.2% for mumps. The rates of seroconversion with protective titers after vaccination for tetanus, diphtheria and hepatitis B were 94%, 67% and 75% respectively. The response to the MMR vaccine was greater than 70%, with a second dose of the vaccine being needed in 26% of patients.

CONCLUSIONS

Susceptibility to vaccine-preventable diseases in transplanted patients is high. The acceptable response to vaccination justifies the development of specific programs. Given the special characteristics of this group of patients, vaccination programs must be simple and flexible.

A new measles mumps rubella (MMR) vaccine: a randomized comparative trial for assessing the reactogenicity and immunogenicity of three consecutive production lots and comparison with a widely used MMR vaccine in measles primed children

OBJECTIVES

A multicenter, single-blind, randomized, controlled clinical study was conducted in healthy 15-18-month-old children in order to assess the immunogenicity and reactogenicity of three consecutive lots of a new measles- mumps-rubella (MMR) vaccine, GSK MMR.

DESIGN

A total of 500 enrolled subjects were randomized into four groups to receive either a single dose of one of the three lots of GSK MMR (three groups--125 subjects in each group) or Merck MMR vaccine (125 subjects). Once clinical consistency had been demonstrated, the data were pooled and compared with the widely used Merck vaccine. Solicited local and general symptoms were recorded using diary cards, and antibody levels were determined using ELISA assays.

RESULTS

No differences in the incidence of local and general symptoms or seroconversion rates were seen in the groups receiving different lots of GSK MMR. Compared with Merck MMR, there was a significantly lower incidence of local pain (P<0.001) and swelling (P=0.038) in infants receiving the GSK MMR vaccine. The incidences of all other solicited local and general symptoms were comparable between the two groups. No signs of suspected meningitis were reported. No serious adverse events were reported by the investigator to be related to vaccination. Equivalent seroconversion rates and postvaccination GMTs were observed in the groups receiving the two MMR vaccines. In conclusion, the new GSK MMR vaccine administered in measles-primed children demonstrated satisfactory immunogenicity and safety profiles as good as the Merck MMR vaccine.

A random cluster survey and a convenience sample give comparable estimates of immunity to vaccine preventable diseases in children of school age in Victoria, Australia

We compared estimates of the age-specific population immunity to measles, mumps, rubella, hepatitis B and varicella zoster viruses in Victorian school children obtained by a national sero-survey, using a convenience sample of residual sera from diagnostic laboratories throughout Australia, with those from a three-stage random cluster survey. When grouped according to school age (primary or secondary school) there was no significant difference in the estimates of immunity to measles, mumps, hepatitis B or varicella. Compared with the convenience sample, the random cluster survey estimated higher immunity to rubella in samples from both primary (98.7% versus 93.6%, P = 0.002) and secondary school students (98.4% versus 93.2%, P = 0.03). Despite some limitations, this study suggests that the collection of a convenience sample of sera from diagnostic laboratories is an appropriate sampling strategy to provide population immunity data that will inform Australia's current and future immunisation policies.

Pediatric sentinel surveillance of vaccine-preventable diseases in Italy

BACKGROUND

Planning and evaluating vaccination programs depend on reliable systems of monitoring disease incidence in the community. In Italy vaccine-preventable diseases are subject to statutory notification, but they are often unreported. In January, 2000, a pediatric sentinel network was launched, with the aim of monitoring in a timely and accurate way the geographic and temporal trends of vaccine-preventable diseases.

METHODS

The network consists of National Health System primary care pediatricians; participation is voluntary. The diseases under surveillance include measles, mumps, rubella, pertussis and varicella. Case definitions are based on specific clinical criteria, and pediatricians report cases on a monthly basis. Incidence rates are estimated and compared with those obtained by statutory notifications. The proportion of vaccinated cases is also computed.

RESULTS

In 2000 an average of 468 pediatricians participated each month of a total of 7276 pediatricians under contract for primary care by the National Health System. The population under surveillance consisted of 371 670 children younger than 15 years (of a national total of 8.347.804 children of the same age). The annual national incidence per 100.000 children was estimated at 5345 for varicella, 1972 for mumps, 279 for pertussis, 108 for rubella and 62 for measles, although wide variations were observed among geographic areas. The national estimates are 3 to 7 times higher than those obtained through statutory notifications. For all of the diseases the ratio between the two sources of data was significantly higher in southern Italy, compared with the rest of the country. The proportion of vaccinated cases was similar for measles and rubella (21 and 17%) but was approximately 3 times higher for mumps (59%). Most (74%) of the vaccinated mumps cases had received the Rubini vaccine strain.

CONCLUSIONS

The sentinel surveillance system is considerably more sensitive than statutory notifications, particularly in southern Italy. The high percentage of mumps cases vaccinated with the Rubini strain indicates a reduced effectiveness of this vaccine. Although further improvements are needed, pediatrician-based sentinel surveillance is a useful tool for evaluating vaccine-preventable disease trends.

[Efficiency of revaccination against epidemic parotitis and immunological safety]

Seventy-eight children aged 6-7 years were subcutaneously revaccinated with L-3 live mumps vaccine. The vaccine is slightly reactogenic and completely safe. The level of antibodies increased on day 10 postvaccination in 80% of children with initially low antibody titers. Subcutaneous revaccination resulted in appearance of anti-parotitis antibodies in nasal secretions of 60% and in the saliva of 20% children, this indicating sufficiently high immunogenic activity of the vaccine.