Economic evaluation of a pentavalent rotavirus vaccine in New Zealand

Presenter: Richard Milne, University of Auckland

Abstract

Objectives: To estimate: (i) rotavirus disease burden in New Zealand children aged under 5 years; and (ii) health benefits, budget impact and cost-effectiveness of incorporating a pentavalent rotavirus vaccine (PRV) into the national immunisation schedule.

Methods: A model was developed to evaluate health benefits and budget impact of vaccinating 5 successive birth cohorts with PRV at $50 per dose and 85% coverage (3 doses). Cost-effectiveness was estimated from the societal perspective in year 5 of the programme, with future health benefits discounted at 3.5% per annum.

Results: By age 5, one in 5 children will have sought medical advice for rotavirus gastroenteritis and one in 43 will have been hospitalised. In 2009 we estimate 1,506 hospitalisations (476 per 100,000; 95% CI 451, 502), 3086 Emergency Department (ED) presentations not requiring hospitalisation and 10,120 cases of rotavirus gastroenteritis managed solely in primary care. Annual societal cost is $7.07M, including 41% from hospitalisation and 25% from caregiver income loss. Health benefits will increase and cost of illness decline by 78% in year 5 as successive birth cohorts are immunised. In the 5th year, 1191 hospitalisations, 2442 ED treated cases, 9762 primary care consultations and 0.8 deaths will be averted. It requires 6 vaccinated children to avoid one primary care consultation, 49 to avert one hospitalisation and 73,357 to prevent one death. The incremental cost is $2.99M and the breakeven price per vaccine dose is $32.39 at 2006 prices. The cost is $2,509 to avert one hospitalisation and $305 to prevent one case seeking healthcare assistance. The cost per life year gained in year 5 is $143,097 and the cost per quality adjusted life year (QALY) gained is $46,092 ($US25,259). The cost per QALY is sensitive to incidence rates, vaccine price and efficacy, loss of quality of life by the child, case fatality and caregiver income loss.

Conclusions: From a societal perspective, addition of PRV to the New Zealand childhood immunisation schedule would confer important clinical gains at a modest cost per QALY gained.