In the midst of Chinese medical staff in Wuhan becoming suspected of contracting viral pneumonia which resulted in them being immediately quarantined, Wuhan hospitals also began to notice that a rising number of cases could not be linked to the Huanan Seafood Wholesale market. Only 27/41 patients identified had been exposed to the market according to the Lancet, evidencing the likelihood of human-to-human transmission. Three weeks after this became apparent to doctors, China contacted the World Health Organisation on December 31st.