Logistical feasibility and potential benefits of a population-wide passive-immunotherapy program during an influenza pandemic.

ABSTRACT: Treatment strategies for severe cases of pandemic influenza have focused on antiviral therapies. In contrast, passive immunotherapy with convalescent blood products has received limited attention. We consider the hypothesis that a passive-immunotherapy program that collects plasma from a small percentage of recovered adults can harvest sufficient convalescent plasma to treat a substantial percentage of severe cases during a pandemic. We use a mathematical model to estimate the demand and supply of passive immunotherapy during an influenza pandemic in Hong Kong. If >5% of 20- to 55-year-old individuals recovered from symptomatic infection donate their plasma (donor percentage > 5%), >67% of severe cases can be offered convalescent plasma transfusion (treatment coverage > 67%) in a moderately severe epidemic (R (0) < 1.4 with 0.5% of symptomatic cases becoming severe). A donor percentage of 5% is comparable to the average blood donation rate of 38.1 donations per 1,000 people in developed countries. Increasing the donor percentage above 15% does not significantly boost the convalescent plasma supply because supply is constrained by plasmapheresis capacity during most stages of the epidemic. The demand-supply balance depends on the natural history and transmission dynamics of the disease via the epidemic growth rate only. Compared to other major cities, Hong Kong has a low plasmapheresis capacity. Therefore, the proposed passive-immunotherapy program is a logistically feasible mitigation option for many developed countries. As such, passive immunotherapy deserves more consideration by clinical researchers regarding its safety and efficacy as a treatment for severe cases of pandemic influenza.

SUBMITTER: Wu JT 

PROVIDER: S-EPMC2840340 | biostudies-other | 2010 Feb

REPOSITORIES: biostudies-other