The U.S. State Department said Wednesday at least one American died in Nigeria from Ebola that he had contracted while in Liberia.
Two other Americans in Liberia have become infected. Both are medical workers who were helping Ebola patients in Liberia.
Elsewhere, two U.S. Peace Corps volunteers in Liberia have been isolated after potential exposure to Ebola, although neither one is showing symptoms of the deadly virus.
A spokeswoman on Wednesday confirmed the two Peace Corps workers “had contact with an individual who later died of the Ebola virus."
The spokeswoman said the two volunteers will return to the United States when they receive medical clearance.
Meanwhile, as a precautionary measure, the U.S. Peace Corps said it will temporarily remove all of its other volunteers from Liberia, Sierra Leone and Guinea.
The agency made the announcement Wednesday, citing the spread of the Ebola virus.
Peace Corps volunteers
There are 102 Peace Corps volunteers in Guinea working in the areas of education, agriculture and health; and 108 volunteers in Liberia and 130 volunteers in Sierra Leone working in education.
The Liberian government earlier on Wednesday ordered the closure of schools across the country and placed non-essential government workers on a mandatory 30-day leave. Liberia's action marks the most aggressive steps taken yet by any West African country to stop the spread of Ebola.
Ebola, labs worldwide, diagnostic and outbreak response
The United Nations World Health Organization recently said nearly 700 people have died from Ebola in Guinea, Liberia and Sierra Leone during the current outbreak of the virus that began in February.
There is no vaccine or cure for Ebola, which is characterized by fever, vomiting, diarrhea, body aches, and unstoppable bleeding from areas such as the eyes, ears and nose.
Health officials trying to contain the outbreak have encountered a widespread lack of cooperation, with many families treating Ebola patients at home instead of admitting them to hospital isolation units.
Others have ignored warnings to wear protective gear when burying those who were killed by the disease.
In Nigeria, where the disease was first detected on Friday, the Health Ministry sent out Twitter messages advising people on how to avoid Ebola, which is spread through direct contact, and giving out emergency numbers to call if they think they have the disease.
Ebola outbreaks, deaths in Africa, as of July 20, 2014
In Sierra Leone, where the chief doctor fighting Ebola succumbed to the disease on Tuesday, the government said Dr. Sheik Umar Khan would be buried “in strict compliance” with rules governing Ebola-related deaths.
According to the World Health Organization, the number of Ebola cases in West Africa stands at just over 1,200, with 672 deaths in Guinea, Liberia and Sierra Leone.
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