Severe psittacosis during pregnancy and suppression of antibody response with early therapy.

A cluster of 3 cases of psittacosis occurred among members of one family. The initial case was a pregnant woman who presented with extensive multilobar infiltrates and severe respiratory distress necessitating mechanical ventilation. Her respiratory failure worsened during 36 h of erythromycin therapy. Improvement coincided with the termination of pregnancy and the initiation of doxycycline treatment. The remaining patients developed milder illness. Serologic assessment of the affected subjects suggests that early treatment may suppress antibody response.