New Delhi, Oct 3 : US researchers have detected the Sudan Ebola virus strain in semen and breast milk among survivors, about eight months after infection, raising concerns about the potential for sexual and mother-to-child transmission.

Nearly 60 per cent of the survivors of an outbreak in Uganda from 2022-23 reported ongoing and debilitating health issues, even two years post-infection, that interfered with their daily lives, noted researchers at Washington State University.

"This is the first time anyone has been able to closely follow Sudan Ebola survivors over the long term, and the results show the virus continues to affect people's lives well after an outbreak ends," said lead researcher Kariuki Njenga, Professor in the WSU's College of Veterinary Medicine.

"Just as concerning is the fact we detected the virus in semen and breast milk, which shows there is a risk survivors could pass on Ebola months after recovery," Njenga added.

Ebola is a severe, often fatal haemorrhagic fever in humans caused by four known strains: Zaire, Sudan, Bundibugyo, and Taï Forest.

The Zaire and Sudan are the deadliest strains, with case fatality rates ranging from 75-90 per cent for Zaire and 55-65 per cent for Sudan.

The study followed 87 survivors from the outbreak in Uganda alongside a control group of 176 community members who had not been infected. Survivors reported symptoms affecting the musculoskeletal system (45 per cent), central nervous system (36 per cent), and eyes (20 per cent) at much higher rates than those in the control group.

Half of the survivors reported multiple persistent symptoms, including memory loss, joint and back pain, and depression that resulted in an inability to perform basic activities. These symptoms remained consistent across the two-year follow-up period.

"These results point to a kind of 'long Ebola,' very similar to what the world has seen with long Covid," Njenga said. "Symptoms did not significantly improve across two years of follow-up, which is why long-term care and support for survivors are critical."

Researchers stopped detecting the Sudan Ebola virus RNA in semen for up to 210 days and in breast milk for up to 199 days after infection. In two men, the virus reappeared in semen samples eight months after consecutive negative results, suggesting possible latency and reactivation.

The study comes amid the ongoing Ebola outbreak in Kasai Province of the Democratic Republic of the Congo (DRC). As of Wednesday, a total of 64 cases had been reported, including 42 deaths, while 12 patients have recovered and been discharged.

The Congolese government declared the outbreak on September 4, marking the country's 16th Ebola outbreak since the virus was first identified in 1976, Xinhua news agency reported.

/IANS