Frieda K. Roth

Reduction in fever and symptoms in young adults with influenza A/Brazil/78 H1N1 infection after treatment with aspirin or amantadine.

During an outbreak of influenza A/Brazil/78 H1N1 infection, 47 volunteers with clinical and virological influenza of less than 2 days duration were treated in a randomized double-blind fashion for 5 days with 100 or 200 mg of amantadine daily or with 3.25 g of aspirin daily. The aspirin treatment group defervesced more rapidly (10.3 h versus 21.5 h and 23.6 h; P less than 0.01), but by the second daily follow-up visit, both groups of amantadine recipients exhibited greater symptomatic improvement. Bothersome side effects resulted in discontinuation of therapy by 35% of the aspirin treatment group but only 3% of the amantadine treatment group (P less than 0.05). Individuals who present to a physician during an influenza A epidemic with characteristic symptoms will experience symptomatic benefit from amantadine treatment, with negligible toxicity.

Double-Blind Evaluation of Oral Ribavirin (Virazole) in Experimental Influenza A Virus Infection in Volunteers

The prophylactic effectiveness of oral administration of ribavirin (1-β-d-ribofuranosyl-1,2,4-triazole-3-carboxamide) against experimentally induced influenza A infection was evaluated in a double-blind clinical trial in normal volunteers. Fourteen men received ribavirin capsules (1,000 mg/day in four divided doses) and 15 other men received identical-appearing placebo capsules beginning 6 h after the intranasal inoculation of 3.4 log10 50% tissue culture infectious doses of influenza virus A/Victoria/3/75 H3N2 and continuing for 5 days after challenge. The total number of moderate-to-severe symptom scores and the total number of temperatures ≥100°F (37.8°C) were significantly lower in the ribavirin group compared with the placebo group. The mean quantity of virus shed in nasal wash specimens and the total number of days that there were viral titers greater than 1.0 log10 50% tissue culture infectious doses per ml were significantly greater in the placebo group. There was no difference between the frequencies of virus isolated or the antibody responses in the two groups. Therefore, prophylactic ribavirin ameliorated symptoms and fever indicative of moderate-to-severe illness, but had no effect on the manifestations of mild illness in response to influenza A challenge. A transient rise in total serum bilirubin occurred in 29% of the ribavirin-treated volunteers and in none of the placebo-treated volunteers.

Evaluation of a Topical Interferon Inducer in Experimental Influenza Infection in Volunteers

The prophylactic and/or therapeutic effect of a low-molecular-weight interferon inducer, CP-20,961, was tested in a double-blind placebo controlled study of experimental influenza A/England/42/72 (H3N2) infection in normal volunteers. Ten volunteers received CP-20,961 and 10 received placebo. Interferon was detected in nasal secretions of nine of the former and three of the latter group (P < 0.05). Seven in each group became ill, and severity of illness was not different. Also, quantitative virus shedding patterns and antibody response were not different between the two groups. The negative result may have been due to the relatively low quantities of interferon induced.