Evaluation of Immunity for Mumps among Vaccinated Medical Students

Abstract

Healthcare workers are considered at higher risk for mumps infection than the general population. Since 2017, the national immunization plan recommended the administration of a dose of measles–mumps–rubella (MMR) vaccine to the healthcare operators who are unable to demonstrate a complete vaccination history or that are seronegative for at least one of the three agents. Regarding mumps infection, based on actual concerns regarding the loss of protection over the years after vaccination, the Advisory Committee on Immunization Practices (ACIP) recommended to administer a third dose of vaccine to operators previously vaccinated with two doses of MMR vaccine who belong to a group at increased risk of mumps infection in the event of an epidemic. This guideline, however, is not currently followed in Italy, resulting in a potential risk for vaccinated operators to become unprotected from mumps over the years. The aim of our study is to evaluate the persistence of a protective antibody level for mumps among medical students vaccinated during infancy or adolescence, at the start of their hospital internship. We retrospectively evaluated mumps-specific IgG levels in a group of medical students, in the period from 1 January to 31 December 2020. We evaluated the persistence of the detectable level of mumps-specific antibodies in relation to their vaccinal status, gender and time elapsed from vaccination. We found that 17.4% (65 subjects) of our sample were seronegative for mumps. The univariate analysis showed a significant difference in serological protection between male and female gender (77.0% vs. 86.2%; p < 0.05 with chi2 test) and between age classes (86.5% vs. 76.4%; p < 0.05 for subjects aged 18–23 years and over 23 years, respectively). Female gender was significantly related to higher serological protection even after adjusting for age classes and number of vaccine doses administered in a multivariate analysis model. Our study shows a substantial percentage of subjects lacking a protective mumps titer among medical students who were vaccinated in childhood. Given the higher risk of infection among those subjects, routine pre-employment screening should be performed among those operators regardless of their vaccination history and a third dose of MMR should be offered to unprotected students.

Prevalence and management of rubella susceptibility in healthcare workers in Italy: A systematic review and meta-analysis

“…After exclusion of duplicate articles in the two databases, there were nine eligible studies [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] ( Table 1 ), of which eight were quantitative [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] and one was qualitative [18] . The remaining 88 studies did not match the inclusion criteria [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] , [42] , [43] , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] , [55] , [56] , [57] , [58] , [59] , [60] , [61] , [62] , [63] , ...…”

Mumps serological surveillance following 10 years of a one-dose mumps-containing-vaccine policy in Fujian Province, China

“…24 Ferrari and colleagues evaluated persistence of a protective antibody level for mumps among medical students who had been vaccinated during infancy or adolescence in Italy, finding that a significant proportion of the students lacked serological protection from mumps. 25 …”

Seroprevalence for Measles, Varicella, Mumps and Rubella in the Trainee Obstetric Population: A Survey in Southern Italy

“…Studies conducted in Northern Europe have documented the presence of antibodies in children derived from the Jeryl Lynn mumps strain, reporting only 73% of people have had seroconversion after a single dose of vaccination [ 46 ]. Ferrari et al [ 14 ] have evaluated the presence of a protective antibody level for mumps in a population of medical students vaccinated during childhood or adolescence in Italy, observing that a significant proportion of the students lacked serological protection from mumps.…”

“…Healthcare workers, due to their job, have a high risk of contracting infections compared to normal people. This makes them an important study group for the prevention of infectious outbreaks at hospital level [ 14 , 15 , 16 , 17 ]. In Italy, it has been described that coverage for recommended vaccinations among HCWs is very low [ 18 ], therefore the aim of the present research was to evaluate the immunization status for vaccine-preventable disease such as measles, mumps, rubella, and varicella in a cohort of 517 trainee obstetricians attending at the University of Campania “Luigi Vanvitelli”, considering that they are the future healthcare workers who will have close contact with pregnant women and unborn children.…”