A former Washington University researcher is the subject of a national manhunt following the killing of a man in Chicago.Microbiologist Wyndham Lathem, 42, is wanted for the stabbing death of a 26-year-old at Lathem's Chicago apartment, authorities say. Another man, this one an employee of Oxford University in the United Kingdom, is also wanted.
Lathem, an expert on the bubonic plague, or "Black Death," completed a post-doctoral fellowship at Wash U in 2007.…