Re: OM: US likely to need bigger antiviral stockpile
Some other points of interest ; this post stops about half-way through from the publication. There are many, many considerations:
* There currently are no pharmacokinetic, efficacy, or safety data for oseltamivir in infants under one year of age or in pregnant women. Because very little zanamivir is absorbed systemically, it has been considered an alternative for pregnant women, but this is not based on adequate data.
* It is important to note, however, that in Europe use of oseltamivir for treatment of seasonal influenza is limited, thus the emergence of resistance may not to be related to use. Japan, with its higher rates of seasonal oseltamivir use has not yet reported an increase in resistant strains. The implications of increasing antiviral resistance for pandemic planning are unclear, but troubling.
* Lipsitch and colleagues (2007) modeled the predicted impact of four strategies for antiviral use on the number of cases and the emergence of resistance: no antivirals; antivirals for treatment only; antivirals forhousehold prophylaxis without treatment; and antivirals for treatment and
household prophylaxis. They predicted that use of antivirals exclusively for treatment led to the least emergence of resistance. Exclusive use forhousehold and seasonal prophylaxis eventually led to significant emergence of resistant virus in the model, but only after some lag time. However, Lipsitch and colleagues predicted that combined use for both treatment and prophylaxis led to the most widespread and rapid emergence of resistant virus.
* Regimens of antivirals cost approximately $70?100 for a 10?capsule treatment course when purchased commercially, compared to approximately $20 per course for government purchases for the SNS.
* The shelf-life of the antivirals in the Strategic National Stockpile held by the federal government is unknown?information is not being disclosed about when antivirals currently stockpiled are expected to expire.
* The committee has learned that some private sector employers are hesitant about assuming the cost of antivirals, a hesitation that is shaped by the many unknowns, the high cost of the medications, questions about shelf-life and the current exclusion of non-federal stockpiles in the shelf-life extension program, and by unease, expressed by some, at the possibilityof government seizure of private stockpiles (Koonin, 2008).
* Recommendation 4-2: The committee recommends that pandemic influenzaplanners at all levels make outbreak prophylaxis for health care and emergency personnel who are in short supply and will have repeated and difficult-to-control exposure a first priority for prophylactic antiviral use. Post-exposure prophylaxis for other health care personnel and emergency responders should be a second priority. Post-exposure prophylaxis of household contacts of infected individuals should be a third priority if stockpiled antivirals are insufficient to meet all prophylaxis objectives.
* In the absence of pharmacologic means of protection, alternate methods for containing disease spread in and beyond the household would be applied, including quarantine and isolation (voluntary or not, depending on
circumstances), and advance instructions for implementing household infection control.
* Pandemic planners could consider strategies to minimize the need for prolonged prophylaxis (and thus decrease the amount of antiviral regimens needed, as well as minimize safety concerns about antiviral use longer than 6 weeks) by limiting health worker exposure to infected individuals. This could perhaps be done by organizing front-line workers into subsets or cohorts and deploying them in turn to care for cases of influenza.
* The recent IOM report Preparing for an Influenza Pandemic: Personal Protective Equipment for Healthcare Workers described maintenance and reusability as two priority areas for research given concerns that personal protective equipment supplies at the state, local, and hospital level are limited and will be depleted rapidly in an influenza pandemic.
* An additional argument for the development and deployment of accurate diagnostics is the ability to adequately identify health care personnel and other ?front-line? workers who develop influenza and recover. They will be able to safely work without prophylaxis or personal protective equipment.
