Dr. Arpadi's research interests concern growth, nutrition, bone and metabolic health, and other long-term outcomes in HIV-infected children and adolescents. He is the Principal Investigator of an NIH-funded study of study of bone health in HIV-infected children on anti-retroviral therapy in Johannesburg South Africa and is currently part of a multi-country collaborative study of implementation "Option B" for prevention of mother to child transmission of HIV in Swaziland. He has authored over 50 peer-reviewed articles and book chapters. He is the co-director of the Epidemiology of HIV/AIDS course for masters and doctoral students at the Mailman School of Public Health.