Medical Studies

Influenza Vaccination: Part III

Jason Shafrin

Yesterday we examined the cost effectiveness of the influenza vaccine in children. Today I will look at two papers which focus on the same question using children as the sub-population of interest. Estimated influenza infection rate among young healthy children is between 35% and 50% each year.

Cohen and Nettleman (2000) look at preschool children and create a cost-benefit scenario under a flexible and fixed (i.e.: 8am – 5pm) schedules. The net cost savings for the vaccination is calculated as below.

No Vac Flexible Fixed
Direct Cost 14.87 14.53 14.53
Indirect Cost 29.16 8.23 28.3
Total Cost 44.03 22.76 42.83
Net Cost -21.27 -1.20

The authors find that direct costs of administering the vaccination can be as little as $4 in an HMO, and up to $10 in an outpatient stand-alone practice. Cost savings from the vaccination results from fewer pediatric office visits (estimated to cost $51/visit) and fewer ER visits (estimated at $124.42/visit) as well as fewer antibiotics used and fewer hospitalizations. Indirect costs included the parental time spent in the doctor’s office with their child as well as time absent from work from having to take care of a sick child.

This analysis shows that flexible vaccination is far superior to fixed schedule vaccination. The problem with this is that it is likely that health care providers would need to be compensated more to work a flexible schedule which may decrease the cost savings. Also, vaccination costs do not count physician rent, utilities, staffing, chart maintenance, etc. which go into the cost of a physician visit.

A second, more reliable study is preformed by Luce, et al. (2001). This study employs data from a multicenter, prospective, randomized, double-blind, placebo controlled efficiency trial during two flu seasons (fall 1996 through spring 1998). The vaccine studied was the live, attenuated, trivalent, intranasal influenza vaccine (not the more commonly used intramuscular shot). It was found that vaccinated children have 1.2 fewer influenza related illness (ILI) fever days/child than unvaccinated children. The costs of the vaccine are analyzed are as follows:

COST CATEGORY
Direct Costs
Resources to administer vaccination
Resources to treat vaccine-associated adverse affects
Resources to treat ILI
Direct non-medical costs
Caregivers’ travel for vaccination
Caregivers’ travel to health care visits from vaccine-related adverse affects
Caregivers’ travel to health care visits for treatment of ILI
Lost Productivity Costs
Caregivers’ missed usual activity to receive vaccine
Caregivers’ missed usual activity as a result of vaccine associated adverse affects
Caregivers’ missed usual activity as’ a result of children’s ILI

For the direct costs, the authors take into account the vaccine cost, time to administer the vaccine, and medication use from adverse affects of the vaccine. To measure the health care resources used to treat ILI, the authors look at expected costs from hospitalization, health care provider visits (ER or physician), laboratory and diagnostic tests and procedures, antibiotics and other prescription or over-the-counter medications.

Direct non-medical costs and lost productivity costs are measure using transportation costs (e.g.: vehicle mileage and parking costs) and caregivers’ time costs respectively. Most of the cost data is culled from other papers or NAMCS and NHAMCS data. The authors find that from society’s point of view, a $28 intranasal vaccination was worth the cost. From an individual’s point of view, an intranasal vaccination costing less than $5 was worth the cost. The individual’s break even value is lower than society’s since the individual does not take into account the externality that if they are vaccinated, it is less likely that someone else becomes infected with influenza.