Costs of Rabies Post-Exposure Prophylaxis According to Pre-Exposure Prophylaxis Status
Costs of PrEP were assessed for the cohort of 4,666 children in the study at the time of PreP administration. PrEP schedule followed the WHO guidelines, with intradermal administration of 0.1 ml volume per site (one site each day) given on days 0, 7 and 28.
The direct medical costs included cost of biologicals (rabies vaccine), cost per shipment, considered as 2% of the vaccine cost, cost of needles, alcohol and cotton used. Costs related to health care staff were not included. The number of doses per vial assumed for the analysis is 4, although in theory 1 vial could be used to deliver 5 x 0.1 mL doses, thus 20% vaccine wastage is built into the calculations.
In addition, to explore further the benefits of such vaccination program, projected costs of two hypothetical cohorts of children bitten by a dog were assessed according to two scenarios:
(i) Scenario 1, no PrEP:
Assessment of the costs related to the expected annual number of children among the study cohort bitten by a dog, assuming they did not have PrEP. These children were considered to follow the standard of care for Post-Exposure Prophylaxis (PEP) defined as 2-site intradermal method (2-2-2-0-1) for use with PVRV (complete PEP), with RIG given for category III bites.
(ii) Scenario 2, with PrEP
Assessment of the costs related to the expected annual number of children among the study cohort bitten by a dog benefiting from PrEP. Following the national guidelines, such patients should be given only two booster doses on days 0 and 3, but no RIG.
Costs associated with wound care (e.g. antibiotics, tetanus immunization) were not included in the analysis since these do not depend on rabies vaccination status of the patient. Indirect costs were also not included in the analysis.
Time horizon for the comparison of the economic benefit of the two
strategies was projected to 1 year, 5 years and 10 years. All medical costs
were expressed in terms of Philippine peso (PhP), and converted to US dollars
(USD) using the average exchange rate of USD 1 = PhP 43.