Piantadosi Lab Projects

Powassan virus is a tick-borne flavivirus that causes encephalitis and has been increasingly detected in the United States. Its primary vector, Ixodes scapularis, is responsible for common infections including Lyme disease. To address the hypothesis that POWV evolution and population expansion in its enzootic cycle have contributed to an increasing incidence of human infections, we are 1) examining the genetic diversity, population size, and population growth of Powassan virus in ticks, and 2) investigating the frequency and clinical manifestations of Powassan virus infection in patients in established cohorts. We are especially interested non-neuroinvasive disease, which is common among other arboviruses, but poorly characterized for Powassan virus.

Dengue is the most common mosquito-borne infection, affecting 400 million people per year, and it encompasses an extremely diverse group of viruses across four serotypes. Disease severity is influenced by a complex interplay between between virus serotype and host pre-existing immunity. To address the hypothesis that similar relationships between virus genotype and host immune response also drive dengue dynamics at the population level, we are investigating dengue virus diversity across space and time in combination with precise immunological profiling to define a virus susceptibility landscape in Merida, Mexico.

Since its recent emergence, SARS-CoV-2 has had profound effects on human health and society, and fundamental questions about its geographic spread, evolution, and pathogenesis are yet to be answered. We are analyzing SARS-CoV-2 genomes from patients in Georgia to understand the timing and source of virus introduction into our community. Working with collaborators at the Yerkes National Primate Research center, we are also investigating associations between genotype and phenotype through in vitro studies and a Rhesus macaque model.

Unknown and underappreciated viruses are important causes of human disease. We use metagenomic sequencing to 1) detect and discover unappreciated/novel viruses in patients with suspected infections of the central nervous system or respiratory system, and 2) characterize the virome of vectors under investigation