1 Department of Medical Microbiology and Research Center of Microbiome, Capital Medical University, Beijing 100069, China.
2 Department of Infectious Diseases, Beijing You'an Hospital, Capital Medical University, Beijing 100069, China.
3 Department of Medical Microbiology and Research Center of Microbiome, Capital Medical University, Beijing 100069; Department of Medical Microbiology and Immunology, University of Turku, Turku 20520, Finland, China.