Ethno-epidemiology of HCV, HIV and Overdose associated with Drug Marketsand Drug Tourism

To respond to the burgeoning SARSCoV-2 epidemic, we propose to leverage the infrastructureof a new binational cohort of 600 people who inject drugs (PWID), as well as additional UCSDinvestigators who have expertise in analysis of social networks, microbiome, and geneticsequencing data to address the proposed aims:Aim 1. To determine the prevalence and correlates of subclinical and symptomatic SARSCoV-2infection among PWID within the SD/TJ border region.Aim 2. To determine the prevalence and correlates of SARSCoV-2 shedding in nasal secretionsand fecal specimens among PWID.Aim 3. To determine network features associated with cross-border transmission of subclinicalSARSCoV-2 infection among PWID.Aim 4: To use molecular epidemiology to determine the global migration of SARSCoV-2 betweenPWID in San Diego and Tijuana and factors associated with local and global dispersal.We will use social network surveys, microbiome analysis and full length SARSCoV-2 sequencingto characterize PWIDs' social network determinants of SARSCoV-2 infection, the influence of themicrobiome on shedding, and the viral genetic migrations within SD, TJ and beyond. Accurateestimates of subclinical infection of SARSCoV-2 and its risk factors are needed to informprevention, treatment, and public policy, especially in a cross-border context where borderclosures have already been implemented as a costly measure to curb transmission.