Not new, but an important epidemiological paper:
Onset Patterns and Course of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (Chu et al., 2019)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370741/
Lily Chu, Ian J. Valencia, Donn W. Garvert, and Jose G. Montoya
Excerpt: