Keywords
There were 11,574 relevant publications with author keywords in the
period from 1991 to 2020. To further identify the main research
directions and core content in the field of coronavirus research, we
classified the author keywords into six categories (Table 1). They were
”Epidemiological features”, ”Biological features”, ”Immune response
features”, ”Age/sex”, ”Diseases/symptoms” and ”Diagnosis/therapy”.
China, which was the origin of the outbreak, conducted numerous studies
on the clinical characteristics and biochemical markers of COVID-19 and
studied the routes of transmission, effective measures to control the
spread of the disease (for instance, rapid outbreak responses and
lockdowns), epidemiological characteristics, diagnostic methods,
treatments (for instance, traditional Chinese medicine) and vaccines. As
the COVID-19 epidemic spread worldwide, the areas of focus in various
countries and territories ranged from epidemiological characteristics,
prevention and control methods, aetiology and antibodies to disease
transmission, detection, diagnosis, treatment and prognosis.