1 Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
2 Department of Pathology & Laboratory Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
3 Department of Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
4 Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA. Electronic address: masayuki.nigo@uth.tmc.edu.