Comparison of self-reported and recorded vaccinations and health effects in Australian Gulf War veterans

Considering Exposure Assessment in Epidemiological Studies of Chronic Health in Military Populations

Exposure assessment is an important factor in all epidemiological research seeking to identify, evaluate, and control health risks. In the military and veteran context, population health research to explore exposure-response links is complicated by the wide variety of environments and hazards encountered during active service, long latency periods, and a lack of information on exposures in potentially vulnerable subgroups. This paper summarizes some key considerations for exposure assessment in long-term health studies of military populations, including the identification of hazards related to military service, characterization of potentially exposed groups, exposure data collection, and assignment of exposures to estimate health risks. Opportunities and future directions for exposure assessment in this field are also discussed.

Seroprotection to vaccine-preventable diseases among workers at a Victorian tertiary hospital

OBJECTIVE

To determine seroprotection for the vaccine-preventable diseases (VPDs) measles, mumps, rubella, varicella and hepatitis B among new employees seen at a Victorian tertiary hospital staff clinic.

METHODS

Employees who presented to the staff clinic for immunisation assessment between 1 January 2012 and 31 December 2013 were included. Demographic data, self-reported disease history and previous vaccination status were reviewed retrospectively to determine impact on serological results.

RESULTS

A total of 1,901 new employees were included, 83% of whom were at risk of direct contact with blood or body substances. Overall, the proportion of workers seropositive to measles was 88%, mumps 90%, rubella 78%, varicella 93% and hepatitis B 80%. Staff born before 1966 were more likely to have positive measles or mumps serology but negative rubella or hepatitis B serology (p<0.05 for each). Staff who self-reported measles (99% vs. 93%, p=0.03) or varicella infection (98% vs. 92%, p<0.001) were more likely to be seropositive, but those reporting previous vaccination to measles, mumps or rubella were no more likely to be seropositive.

CONCLUSIONS AND IMPLICATIONS

This study demonstrated levels of seropositivity of 78-93% for the five VPDs. Despite recognised limitations of serological testing, 10-20% of new employees to a healthcare institution lacking seroprotection represents a potentially unacceptable risk of nosocomial transmission of these VPDs. Our findings support ongoing serological testing of new healthcare staff at risk of direct contact with blood or body substances.