Recent decades have seen expansions in the subfield of pathogen genomic epidemiology, also called ‘molecular epidemiology.’ Practitioners in this area analyze pathogen genetic sequence data to identify the emergence of pathogen subtypes or ‘variants,’ including ones that have evolved to have problematic biological characteristics such as greater transmissibility or treatment resistance. The field’s prominence has led to public controversies surrounding applications of pathogen genomics in disease control. The most highly visible examples occurred during the COVID-19 pandemic, when the designation of SARS-CoV-2 ‘Variants of Concern’ by the World Health Organization shaped public health strategies, media stories, and everyday talk about the pandemic. Drawing on several cases, I argue that controversies around uses of pathogen genomics have driven the emergence of a novel kind of socio-technical form, which I call a ‘molecular public.’ Molecular publics materialize when pathogen genomic science enters public discourse through news media or similar means, followed by people recognizing themselves as being potentially at risk of becoming infected with a particular pathogen subtype or affected by policy responses to a variant. I present molecular publics as a useful analytic for social studies of infectious disease and a vector through which novel biosocialities mediated by pathogens can emerge.

近几十年来，病原体基因组流行病学（也称为“分子流行病学”）子领域得到了扩展。该领域的从业者分析病原体基因序列数据，以识别病原体亚型或“变体”的出现，包括那些已经进化出有问题的生物学特征（例如更大的传播性或治疗耐药性）的病原体亚型或“变体”。该领域的突出地位引发了围绕病原体基因组学在疾病控制中的应用的公众争议。最引人注目的例子发生在 COVID-19 大流行期间，当时世界卫生组织将 SARS-CoV-2 指定为“值得关注的变种”，这影响了公共卫生策略、媒体报道和有关该流行病的日常讨论。根据几个案例，我认为围绕病原体基因组学使用的争议推动了一种新型社会技术形式的出现，我将其称为“分子公共”。当病原体基因组科学通过新闻媒体或类似方式进入公众话语时，分子公众就会具体化，随后人们认识到自己有可能感染特定病原体亚型或受到针对变体的政策反应的影响。我将分子公众作为传染病社会研究的有用分析方法和病原体介导的新型生物社会性的载体。