    Sentence 1: Who challenged the  plague theory first?    Sentence 2: The plague theory  was first significantly  challenged by the work of  British bacteriologist J. F.  D. Shrewsbury in 1970, who  noted that the reported rates  of mortality in rural areas  during the 14th-century  pandemic were inconsistent  with the modern bubonic  plague leading him to  conclude that contemporary  accounts were exaggerations.    