Complex sentence: Smith was frequently consulted in fever epidemics and on sanitary matters by public authorities, and his reports on quarantine (1845), cholera (1850), yellow fever (1852), and on the results of sanitary improvement (1854) were of international importance.
Split into simpler sentences: Smith was frequently consulted in fever epidemics and on sanitary matters by public authorities. His reports on quarantine (1845), cholera (1850), yellow fever (1852), and on the results of sanitary improvement (1854) were of international importance.