Stockpiling vaccines requires authorities to peek into the future. When H1N1 was causing panic in 2009, the U.S. predicted it would need 160 million vaccine doses. But demand never took off, and the U.S. destroyed 40 million out-of-date vaccines in 2010.
Now U.S. authorities are trying to figure out what they need to protect against H7N9, a possible pandemic that has, perhaps temporarily, tapered off. The arrival of cold weather--or, worse still, human-to-human transmission--could see viral spread accelerate, though. Whether these risks are real enough to warrant stockpiling is now up for debate, and the National Vaccine Advisory Committee (NVAC) met to discuss the topic this week, CIDRAP News reports. NVAC advises the Department of Health and Human Services, so its findings could feed into U.S. policy.
Robin Robinson, director of HHS's Biomedical Advanced Research and Development Authority, told the committee that federal officials are weighing who to vaccinate, what vaccine platforms to include, production capacity, timing and cost. After considering these factors, Robinson and others will make a decision on stockpiling, possibly by this summer. One decision has already been made--pandemic preparations should not delay seasonal flu vaccine manufacturing. Robinson also believes that the situation may favor adjuvanted vaccines, which can generate immunity in fewer doses. Adjuvanted vaccines could prove a tough sell in the U.S., though. Previous campaigns have avoided the use of adjuvants, and links between the boosters in GlaxoSmithKline ($GSK) shots and narcolepsy is likely to dampen public interest.
The immune-response boost provided by adjuvants could help vaccines overcome anticipated difficulties in protecting people against H7N9. "Historically, H7 vaccines haven't provided a very rosy picture for us. We have our work cut out," Robinson said. Details of the effectiveness of the vaccines will begin to emerge later this year, with clinical trials due to start in August. The NVAC meeting heard that egg-based production is again suffering from low antigen yield, but--unlike in previous years--alternatives are available. Recombinant vaccines are giving better yields, and development is ahead of egg-based alternatives.
- check out the CIDRAP News article