Norma Melendez, a community health worker with City Health Works, walks along Second Avenue on her way to meet a client. City Health Works is an organization that is attempting to bring an African model of health care delivery to the United States. Bryan Thomas for NPR hide caption

itoggle caption Bryan Thomas for NPR

A man carries old plastic containers in March 2012 through the Kibera slum in Nairobi, Kenya. Kenyans living in poverty often collect plastics that they can turn into cash by taking it to companies that recycle it. Carl de Souza/AFP/Getty Images hide caption

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A woman on the L train in New York City last week covers her face, fearful because a doctor with Ebola rode the train days earlier. Epidemiologists say people on the subway were not at risk. Stephen Nessen /WNYC hide caption

itoggle caption Stephen Nessen /WNYC

Scenes from an outbreak: Ebola survivor Dr. Kent Brantly; Texas Health Presbyterian Hospital in Dallas; A worker cleans the apartment where Ebola victim Thomas Eric Duncan stayed in Dallas; experimental vaccine; the Carnival Magic cruise ship off Cozumel, Mexico. Jessica McGowan/Getty; Mike Stone/Getty Images; Jim Young/Reuters/Landov; Steve Parsons/AP; Angel Castellanos/AP hide caption

itoggle caption Jessica McGowan/Getty; Mike Stone/Getty Images; Jim Young/Reuters/Landov; Steve Parsons/AP; Angel Castellanos/AP

Nina Pham, shown here in a 2010 college yearbook photo, became infected with Ebola virus while caring for Thomas Eric Duncan in a Dallas hospital. Courtesy of tcu360.com/AP hide caption

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Thomas Eric Duncan died at Texas Health Presbyterian Hospital in Dallas Wednesday morning. He is the first person to have been diagnosed with Ebola in the United States. LM Otero/AP hide caption

itoggle caption LM Otero/AP

A private security guard patrols the apartment building in Dallas where Ebola patient Thomas Duncan stayed. The family that hosted him is quarantined. Tom Pennington/Getty Images hide caption

itoggle caption Tom Pennington/Getty Images