Effect of the Host in Action of Sulfonamides on Elementary-Body Agents of Murine and Feline Pneumonitis.

Chemotherapy of Virus and Rickettsial Infections

“…In general, sulfonamides have been found to be ineffective against human infections with psittacosis and closely related viruses (106,107). Trachoma (87,102,103) Inclusion blennorrhea (87,101) Resistant Ornothosis (80,81) Meningopneumonitis (80,89,100) Pneumonitis , Borg and SF strains (80,81) Psittacosis (other strains) (106 to 109) Feline pneumonitis (104,105) At concentrations of SO mg. per cent, sulfonamides do not decrease the survival time of psittacosis virus (6 BC) in Maitland tissue cultures under conditions where the virus is not actively growing, although virustatic effects are observed in roller tube tissue cultures where active growth of virus does occur (76). The general experience with agents in this group, with the possible exception of mouse pneumonitis (88), is that sulfonamides are virustatic only (76,80,81).…”

“…Strains, such as feline pneumonitis, which are resistant to sulfonamides in one host may be slightly inhibited by large doses in another species (105). In general, sulfonamides have been found to be ineffective against human infections with psittacosis and closely related viruses (106,107).…”

The Reversal by Paba of Sulfonamide Inhibition of the Viruses of Lymphogranuloma Venereum and Mouse Pneumonitis

“…We applied this method to the study of the antagonism of PABA on the chemotherapeutic action of sulfonamides for the LGV virus in mice and extended this investigation to developing chick embryos. Because the mouse pneumonitis virus has been found to be susceptible to sulfonamides (Eaton and Hanford, 1945;, similar experiments were done to see whether the same phenomenon occurred with this virus.…”

“…The imal effective dose of various sulfonamides for the mouse pneumonitis virus has been determined (Eaton and Hanford, 1945), but for the purposes of the present experiments a more exact measurement was necessary to adjust the dose to a level such that the degree of pulmonary consolidation of the treated mice would be reduced to about 50 per cent of that of the controls. The results with the mouse pneumonitis virus are summarized in table 1.…”

“…for bacteria in terms of sulfanilamide coefficient, which is closely related to the amount of PABA needed to nullify the antibacterial effect of a given quantity of the sulfonamide (Woods, 1942), it seemed worth while to carry out experiments on antagonism between the PABA and S.A. with these viruses in order to find out whether the same phenomenon applied here. Previous studies had indicated that the minimal effective dose of sulfanilamide for these viruses was 10 mg per mouse per day (Eaton and Hanford, 1945), and this dose was used in the experiments on antagonism.…”