Editor—Cooper et al outlined the role of neurominadase inhibitors in prophylaxis against and treatment of influenza.1 These agents would be important during the early phase of any outbreak of influenza. Nevertheless, their efficacy would be reduced if they were not primed to resist the adverse conditions encountered in the field.
Like vaccines, the potency of antiviral drugs is only maintained during storage at controlled temperatures not exceeding 25-30°C.2 Inadvertent exposure to temperatures above this could easily happen. Also, in 1992 temperatures inside refrigerators in paediatric clinics in Los Angeles exceeded 8°C in 22% of cases.3 Power cuts are also a threat.
Designers of prospective influenza vaccines and chemotherapeutics should therefore ensure that such products can withstand environmental rigours while being transported at short notice to different continents during a pandemic. Adding pirodavir and deuterium oxide to the most labile of the childhood vaccines, live poliovirus vaccine, has resulted in vaccine immunogenicity being maintained after 10 hours of exposure to 42°C.4 Practitioners of clinical medicine and public health need also to appreciate the value of storing influenza therapeutics or prophylactics according to manufacturers' recommendations during epidemics.
Competing interests: None declared.
References
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