Jessica Lin, MD MSCR

EMAIL: jessica_lin@med.unc.edu

PERSONAL WEBSITE: https://www.med.unc.edu/microimm/directory/7396/

PUBLICATIONS: Publications Link

Human-to-mosquito transmission of malaria: Efforts to eliminate malaria altogether hinge on the ability to prevent transmission. We showed that single dose primaquine added to ACT is effective in blocking transmission of multidrug resistant parasites to mosquitoes. We have used mosquito feeding studies to demonstrate the importance of microscopic gametocytemia as a key to identifying the infectious reservoir in Southeast Asia. Since much malaria is asymptomatic and submicroscopic, my current efforts are centered on assessing determinants of transmission from asymptomatic, low-density infections in Africa. We are concluding a multi-year field study in Bagamoyo, Tanzania that pairs PCR diagnosis of malaria with mosquito skin feeding assays. The rich sample bank of human and mosquito samples generated will be used to determine host and parasite factors that affect transmissibility at low parasite densities, and to track the genetic diversity of parasites that persist within human hosts through time and through transmission to mosquitoes. This work has implications for which field deployable diagnostics are most suited to malaria elimination efforts and understanding how mosquito-borne transmission affects parasite evolution and the spread of drug resistance.

Malaria relapse: Plasmodium vivax is the second most prevalent malaria species in the world and causes much morbidity through its ability to reactivate from the liver and cause relapse. Safe and effective treatments are lacking, further complicated by the difficulty of distinguishing re-infections from relapse. We have teamed with investigators Asia to characterize genotypic signatures of relapse in well-defined cohorts using next generation sequencing techniques. More recently, I have established a cohort in Tanzania to investigate relapse patterns in Plasmodium ovale, a neglected parasite species that is growing in prevalence across Sub-Saharan Africa. We are exploring the population genetics of this parasite in Africa and teaming with collaborators to link in vitro and in vivo relapse phenotypes. The long-term goal of this work is to identify biomarkers and parasite genetic determinants of relapse that can guide elimination efforts and lead to the development of new therapies.

SARS-CoV-2 transmission: Households are hotspots for SARS-CoV-2 transmission. In 2020, I led one of the few prospective studies to date of household transmission in the US. We documented a 32% incident attack rate, with increased transmission in minority households. We also  linked higher nasopharyngeal viral loads with increased transmission. We have extended the cohort to study the duration of naturally acquired immune protection, and I continue to be involved in ongoing studies of SARS-CoV-2 transmission within households.