Complex sentence: As his condition worsened, he was treated with intravenous ribavirin, and although he initially survived the critical stage of Lassa fever, Conteh died from renal failure on April 4,18 days after first becoming infected with the Lassa virus.
Split into simpler sentences: As his condition worsened, he was treated with intravenous ribavirin. Conteh initially survived the critical stage of Lassa fever, but died from renal failure on April 4,18 days after first becoming infected with the Lassa virus.