1918-20 年間，全球曾爆發重大的流感疫情，於世界各地皆造成莫大災況，臺灣亦無法自免於傳染病的侵襲。在1918 年，包含現今台南、高雄大部分地區的台南廳地域為西部行政區中受創最深者，無論是患者數（153,857 名）、死亡者數（6,787 名）、致死率（4.41％）、人口平均千人死亡數（11.69 名），皆在西部行政區內名列首位，感染率亦高居第二。為何會是台南廳？本文嘗試使用當時的新聞記載、醫學雜誌、統計分析等素材，分就公共衛生體系與社會情況進行分析，並提出數個假設原因。其成因包括公衛體系的輕忽、社經地位的差異下造成的健康不平等、性別因素對於就醫意願的影響，加上集村聚落類型與便利的交通網絡加速病毒間的傳播等因素，方使得台南廳成為此次大流感疫情下受創最深的地區。

The Spanish influenza epidemic during 1918 to 1920 has caused a tremendous
disaster globally and Taiwan is no exception. In 1918, the Tainan government then,included current most part of Tainan and Kaohsiung area, wa s the most impacted region. No matter whether on the patient number (153,857), death number (6,787),death rate (4.41%), or average death number per 1000 (11.69) were all at the first place in western district. Why Tainan? This article attempted to analyze the public health system and social circumstance based on the news reports, medical magazines, and statistic data at the time to propose several possible factors. The
factors are, neglect of public health system, heath inequity caused by social and economic gap, gender factor on the willingness of seeking medical advise, as well as the cluster village and convenient traffic network speeded up the spread of virus.Therefore Tainan region became the most impacted area of Influenza A virus subtype epidemic.