[A look back at 2 mumps outbreaks]

Mumps orchitis in the post-vaccine era (1967-2009): a single-center series of 67 patients and review of clinical outcome and trends

Since the introduction of the mumps vaccine, the age of appearance of mumps infection has shifted from children to adolescents and young adults, groups with a higher incidence of disease complications and sequelae. During the years 2000-2001, the Gran Canaria Island was part of an epidemic of mumps. In that period, our institution attended 67 cases of serologically confirmed acute mumps orchitis, the most serious complication of mumps infection in young postpubertal males. We conducted a descriptive and prospective study of this cohort and extensively reviewed the literature from 1967 (the year the first mumps vaccine was introduced) to 2009. Fifty-six patients were admitted because of general impairment and were treated with alpha-interferon. Sixty-six patients presented parotitis previous to orchitis (interval from parotitis to orchitis, 4.9 d). Orchitis was unilateral in 89.5% and bilateral in 10.4% of cases. More than 98% of patients had orchitis-associated fever. Nine patients had clinical and biochemical data showing acute mumps meningitis, and 11 had subclinical pancreatitis. The mean duration of symptoms was 4.6 days (range, 1-9). During the acute phase, more than 41% of the evaluated testes had a volume >25 mL. Acute hormonal disturbances were highly prevalent. These included decreased levels of testosterone and inhibin B with low or normal levels of gonadotropins in 35% of subjects, and, to our knowledge not previously reported, an atypical hormonal pattern consisting of low levels of free testosterone and inhibin B, along with increased measures of luteinizing hormone but low or normal follicle-stimulating hormone levels (11% of cases). During the follow-up period (mean, 331 d) a high incidence of sperm disturbance was found.

Mumps outbreaks in vaccinated populations: are available mumps vaccines effective enough to prevent outbreaks?

Increased reports of mumps in vaccinated populations prompted a review of the performance of mumps vaccines. The effectiveness of prior vaccination with 1 dose of vaccine ranged from 72.8% to 91% for the Jeryl Lynn strain, from 54.4% to 93% for the Urabe strain, and from 0% to 33% for the Rubini strain. Vaccine effectiveness after 2 doses of mumps vaccine was reported in 3 outbreaks and ranged from 91% to 94.6%. There was evidence of waning immunity, which is a likely factor in mumps outbreaks, aggravated by possible antigenic differences between the vaccine strain and outbreak strains. Inadequate vaccine coverage or use of the Rubini vaccine strain accounted for the majority of outbreaks reviewed; however, some outbreaks could not be prevented, despite high vaccination coverage with 2 doses of the Jeryl Lynn vaccine strain. Our findings indicate the need for more-effective mumps vaccines and/or for review of current vaccination policies to prevent future outbreaks.

Comparative efficacy of Rubini, Jeryl-Lynn and Urabe mumps vaccine in an Asian population

OBJECTIVE

The comparative efficacy of the three mumps vaccine strains (Jeryl-Lynn, Urabe and Rubini) was conducted in an Asian population from data arising from an epidemiological investigation of seven institutional outbreaks of mumps in Singapore.

METHODS

Demographic information (gender, age, ethnic group), clinical presentation and vaccination history (date and place of mumps vaccination, type of mumps vaccine received) of all children who attended the six childcare centres and one primary school where outbreaks of 20 or more cases of mumps occurred in 1999 were collected. The attack rate of the unvaccinated group and the attack rates of the vaccine groups (for each vaccine strain) were determined and the vaccine efficacy of the three vaccines calculated.

RESULTS

The vaccine efficacy of the Jeryl-Lynn strain, Urabe strain and Rubini strain mumps vaccine were 80.7, 54.4 and -55.3%, respectively.

CONCLUSION

Rubini strain mumps vaccine conferred no protection and has since been deregistered in Singapore.

Study of the immune response engendered by differents combined measles, mumps and rubella (MMR) vaccines in an area of Andalusia (Spain)

The objective of the study is to evaluate and compare the degree of serological protection conferred by the three components of two MMR vaccines: "Vac triple MSD" (Aventis Pasteur MSD) and "Triviraten" (Berna), and to study the effects of a second dose of "Priorix" (Glaxo SmithKline), in an unprotected population. In March 2001, this study was conducted in a sample of 86 children aged 3 and 4 years, in two Basic Health Zones of Cádiz (Spain). Mumps, measles and rubella antibody titers were evaluated by IgG enzyme linked immunosorbent assay (ELISA). All the children showing lack of response were revaccinated with the vaccine "Priorix" of GSK; in 12 of these children (all vaccinated previously with "Triviraten"), studies confirmed the existence of seroconversion utilizing the same methodology. The most outstanding finding has been the low percentage of children vaccinated with "Triviraten" possessing protective titers (>1:500) against mumps (14.3%) compared with those vaccinated with "Vac triple MSD" (81.1%, P<0.000001); geometric mean values (GMT) of 164 and 1631, respectively, were obtained. Significant differences, and in the same direction, were also found in respect of measles (83.7 and 100%, and GMT of 889 and 5076), although not so striking. However, all the children studied did have protective titres (>16UI/ml) of antibodies against rubella. Of the 12 children studied who had not responded with protective titers of anti-mumps antibodies, eight children (66.7%) showed seroconversion with "Priorix", and only one child (25%) presented seroconversion in the response to measles. We have thus proved that the "Rubini" strain provides insufficient protection against mumps in our child population. We have also found that the "Edmonston-Zagreb" strain confers less protection against measles than the "Enders" strain, although the "Schwarz" strain, after revaccination of the children who had failed with the "Edmonston-Zagreb" strain, did not achieve a satisfactory seroconversion, either.

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.

[Vaccination coverage in young children and school children in the Bern canton]

In 1995 immunization coverage at 24 months of age and after the first school year was estimated according to the method recommended by the WHO. Vaccination booklets of 840 children born in 1986, 1987, 1988 or 1991 in the Canton of Berne were reviewed. The response rate was high (96%). The immunization coverage at 24 months of age were for measles 74%, for mumps and rubella (MMR) 72% higher than for diphteria (D), tetanus (T) (62%) and poliomyelitis (polio) (60%) (4 doses) (p < 0.0001). Of the Swiss children born in 1991 32% were vaccinated against tuberculosis. Children 24 months of age of all years had generally a similar immunization coverage. The 101 children of foreign nationalities showed somewhat lower vaccination rates. Immunization uptake for MMR, DT and polio (4 doses) increased over time, so that children born in 1986 at 8.5 years of age had the rate (> 95%) to be reached at the end of the second year of life. After the first school year 88% of the 8.5 years old children presented a vaccination against MMR and 91% a vaccination against measles. Intensified efforts are necessary to achieve a higher immunization coverage at 24 months of age especially among children of foreign nationality, a timely administration of vaccines according to recommended immunization schedule and to restrict BCG vaccine to children at increased risk of tuberculosis.