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The COVID-19 pandemic highlighted the importance of global genomic surveillance to monitor the emergence and spread of SARS-CoV-2 variants and inform public health decision-making. Until December 2020 there was minimal capacity for viral genomic surveillance in most Caribbean countries. To overcome this constraint, the COVID-19: Infectious disease Molecular epidemiology for PAthogen Control & Tracking (COVID-19 IMPACT) project was implemented to establish rapid SARS-CoV-2 whole genome nanopore sequencing at The University of the West Indies (UWI) in Trinidad and Tobago (T&T) and provide needed SARS-CoV-2 sequencing services for T&T and other Caribbean Public Health Agency Member States (CMS). Using the Oxford Nanopore Technologies MinION sequencing platform and ARTIC network sequencing protocols and bioinformatics pipeline, a total of 3610 SARS-CoV-2 positive RNA samples, received from 17 CMS, were sequenced in-situ during the period December 5th 2020 to December 31st 2021. Ninety-one Pango lineages, including those of five variants of concern (VOC), were identified. Genetic analysis revealed at least 260 introductions to the CMS from other global regions. For each of the 17 CMS, the percentage of reported COVID-19 cases sequenced by the COVID-19 IMPACT laboratory ranged from 0·02% to 3·80% (median = 1·12%). Sequences submitted to GISAID by our study represented 73·3% of all SARS-CoV-2 sequences from the 17 CMS available on the database up to December 31st 2021. Increased staffing, process and infrastructural improvement over the course of the project helped reduce turnaround times for reporting to originating institutions and sequence uploads to GISAID. Insights from our genomic surveillance network in the Caribbean region directly influenced non-pharmaceutical countermeasures in the CMS countries. However, limited availability of associated surveillance and clinical data made it challenging to contextualise the observed SARS-CoV-2 diversity and evolution, highlighting the need for development of infrastructure for collecting and integrating genomic sequencing data and sample-associated metadata.新冠（COVID-19）大流行凸显了全球基因组监测的重要价值——该手段可用于监测新型冠状病毒（SARS-CoV-2）变异株的出现与传播，并为公共卫生决策制定提供科学依据。直至2020年12月，大多数加勒比国家的病毒基因组监测能力仍极为有限。为破解这一局限，“新冠病原体控制与追踪分子流行病学项目（COVID-19 IMPACT）”正式启动：该项目在特立尼达和多巴哥（T&T）的西印度群岛大学（UWI）搭建了新型冠状病毒全基因组纳米孔测序平台，并为特立尼达和多巴哥及其他加勒比公共卫生机构成员国（CMS）提供亟需的新冠病毒测序服务。本项目采用牛津纳米孔科技（Oxford Nanopore Technologies）MinION测序平台、ARTIC网络测序方案及生物信息学分析流程，于2020年12月5日至2021年12月31日期间，对来自17个加勒比公共卫生机构成员国的共计3610份新冠病毒阳性RNA样本完成了就地测序。研究共鉴定出91个Pango进化分支，其中包含5种关切变异株（VOC）。遗传分析结果显示，至少有260次新冠病毒从全球其他地区传入上述加勒比公共卫生机构成员国。针对17个成员国，新冠IMPACT实验室完成测序的新冠确诊病例占当期报告病例的比例介于0.02%至3.80%之间（中位数为1.12%）。截至2021年12月31日，本研究提交至全球流感共享数据库（GISAID）的序列，占该数据库收录的来自17个成员国的所有新冠病毒序列总量的73.3%。项目实施期间，通过扩充人员配置、优化实验流程及完善基础设施，有效缩短了向送检机构反馈测序结果及向GISAID上传序列的周转时长。本研究搭建的加勒比地区基因组监测网络所获得的研究结论，直接为加勒比公共卫生机构成员国的非药物干预措施制定提供了关键支撑。但由于相关监测数据与临床数据的可及性不足，难以对观测到的新冠病毒多样性及进化特征进行情境化解读，这凸显出搭建用于收集、整合基因组测序数据及样本关联元数据的基础设施的迫切需求。