Sir
The results of J Cinatl and colleagues1 show that interferon beta is effective against SARS-CoV—a membrane-enclosed RNA virus2—in vitro, when used either alone or in combination with other antiviral drugs.
Their results concur with our beliefs that interferon, with its broad-spectrum antiviral activity against RNA viruses, might be useful in the treatment of SARS, either as a monotherapy or plus ribavirin.
However, the findings of Ozes and co-workers3 show that the specific activity (antiviral units/mg) of recombinant human interferon-consensus 1 (IFN-Con1) was ten-fold higher than that of interferon alfa-2a and interferon alfa-2b in vitro. Furthermore, IFN-Con1 increases the ability of or induces natural killer cells to kill target cells to a greater extent than does interferon alfa.3
Therefore, we suggest that IFN-Con1 and IFN-Con1 plus ribavirin are assessed as potential antiviral drugs for the treatment of SARS with the method used by Cinatl and colleagues.
References
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