Nigeria’s confirmed Ebola patient is the wife of a Swiss diplomat based in Abuja, with Switzerland’s government saying she is believed to have contracted the virus while travelling in Uganda.

The 42-year-old Ugandan-born woman tested positive for Bundibugyo virus disease, a type of Ebola, on October 20, marking Nigeria’s first confirmed case in more than a decade.

According to Reuters, Switzerland’s Federal Department of Foreign Affairs said on Thursday that the woman had spent about a week receiving treatment at a private clinic in Abuja before her diagnosis.

The Swiss government said she was believed to have contracted the virus during a trip to Uganda approximately two weeks earlier. Her husband, who travelled with her, had been placed in isolation but had not developed symptoms, according to the statement.

The precise source of the woman’s infection remains under investigation, as health authorities work to reconstruct her movements and identify possible exposure to the virus.

Conflicting accounts have emerged over whether she travelled to the Democratic Republic of the Congo (DRC), where the current outbreak was first reported in May.

Ugandan officials had said she visited eastern DRC before travelling through Uganda. However, the World Health Organisation (WHO) and the Africa Centres for Disease Control and Prevention (Africa CDC) said they had not received verified information confirming that she had visited the country.

Africa CDC official Wessam Mankoula said Nigeria and Uganda were exchanging information to establish the woman’s movements and possible source of infection.

“So far, there is no validated information (that) this case traveled to DRC (Democratic Republic of Congo),” Mankoula told an online press conference on Thursday.

The WHO representative in Nigeria, Pavel Ursu, said information available to the organisation indicated that the woman had been in Uganda from September 16 and returned to Abuja on October 3.

Ursu also said the patient remained hospitalised, with her biochemical markers reportedly improving at the time of his remarks.

WHO emergency response manager Patrick Otim said investigators were still working to determine the source of the infection and identify the health facilities the woman visited after developing symptoms but before she was admitted to hospital.

The investigation is particularly important because Nigeria’s case is part of a wider outbreak of Bundibugyo virus disease that has affected multiple African countries. Health authorities are examining travel histories and potential links between cases to establish how the virus is spreading.

According to the WHO, Nigeria confirmed the imported case on October 20 after laboratory testing detected the virus in the woman, who had recently travelled from Uganda. She developed symptoms on October 7 and sought medical attention at a private health facility in Abuja on October 11.

As of October 20, 44 contacts had been identified for monitoring, while public health authorities continued contact tracing and other containment measures.

Ebola can spread through direct contact with the blood or other bodily fluids of an infected person who has developed symptoms, or through contaminated materials. Symptoms may include fever, weakness, vomiting and diarrhoea, while severe illness can be fatal.

Health authorities are continuing investigations to establish the patient’s movements, determine the likely source of infection and identify anyone who may have been exposed.

The WHO has urged continued surveillance, contact tracing and coordination between countries affected by the outbreak as efforts to prevent further transmission continue.