An investigation of media for the long term storage of three respiratory viruses

Summary A new transport medium based on agar and charcoal (AC) was compared with a recently modified conventional medium consisting of Hanks' balanced salt solution containing albumen and HEPES buffer (HH). Rhinovirus 2, influenza B and Coxsackievirus A21 were stored in the two media at room temperature, 4°, –20° and –70° C and titrated at various times. Rhinovirus 2 was stable for up to 17 weeks when stored at –70°, –20° or 4° C in HH medium or at –70° or 4° C in AC medium but was unstable in AC medium at –20° C. Influenza B survived well only at –70° C in HH medium and appeared to be inactivated by AC medium. Coxsackievirus A21 was stable in both media at –70° and –20° C. Collection of clinical material into both media suggested HH medium was superior for rhino-viruses. This medium was used in the Antarctic for the collection and transport of nasal swabs back to the U.K. Rhinovirus 2 was isolated from 79 of 268 swabs when they were examined over ten months later. This is the first time rhino viruses have been isolated from men in Antarctica and confirms the value of HH medium.W.H.O. Visiting Worker from Laboratoire National de la Santé Publique, 25 Boulevard Saint-Jacques, Paris, XIV, France.