British national in Sierra Leone tests positive for Ebola virus

(CNN) -- A British citizen who lives in the West African nation of Sierra Leone has tested positive for the Ebola virus, according to Britain's Department of Health.

The man, simply identified as "William," was living in a home established by an American university for researchers in Sierra Leone.

"William" was a volunteer nurse in Kenema Government Hospital and was working with Ebola patients in the hospital, according to Dr. Robert Garry of Tulane University. Garry is manager of the university's program that researches Ebola. The hospital is run by the government of Sierra Leone, but receives support from Tulane researchers.

Garry said that no one else living in the house was "significantly exposed" and "William" is still in Sierra Leone.

According to the Tulane doctor, "William" got sick on Friday and had a low viral load, meaning he wasn't infected for a long time. Garry added that the British national has a fever but none of the other symptoms of the Ebola virus.

In a statement, posted on the United Kingdom's government website Saturday, British Chief Deputy Medical Officer John Watson said the overall risk to the public in the UK is very low.

Watson also said that medical experts are "assessing the situation in Sierra Leone to ensure that appropriate care is provided."

According to the UK Department of Health website, "the UK government is closely monitoring the spread of the Ebola virus in Sierra Leone, Liberia and Guinea." The statement adds that this is the largest outbreak of the Ebola virus in recent times.

Ebola is one of the world's most virulent diseases, according to the World Health Organization.

According to the WHO's website, the virus is introduced to human populations through the human handling of infected animals -- like fruit bats, gorillas and monkeys, to name a few -- found sick or dying in the rainforest.

The infection is then transmitted among humans through direct contact with the blood and bodily fluid of infected people.

WHO's maps of confirmed cases show the Ebola outbreak still is limited to four West African nations -- Liberia, Sierra Leone, Guinea and Nigeria. So far, nearly 2,500 suspected cases have been reported in what the WHO is the worst known outbreak of the disease.

However, the WHO's website says the survival rate for people with Ebola in this outbreak has been 47%, which is a substantial improvement over the disease's survival rate, historically.