Via The Lancet: WHO investigates mysterious outbreak in South Sudan. Excerpt:
A team from WHO's Regional Office for Africa is investigating a mysterious viral haemorrhagic fever outbreak in northern South Sudan that has killed ten people. At the same time, national health officials are scrambling to put preventive measures in place based on the scant knowledge they have so far. However, in a country where nearly two and a half years of fighting has left the health system in tatters, it is unclear how effective those efforts will be.
The outbreak was first reported to national health officials in March, but John Rumunu, South Sudan's director general of preventive health services for the Ministry of Health, said it might have started as early as December, 2015. The symptoms include unexplained bleeding, vomiting, and fever.
52 suspected cases (most infections have been in people younger than 20 years) have occurred so far in two counties near South Sudan's border with Sudan, although there has been only one new patient since early May. The country is still taking precautions, Rumunu said, given that officials remain in the dark over how the syndrome is transmitted or what it even is.
Laboratory tests of samples have so far been negative for the more common haemorrhagic fevers, including Ebola virus disease, Marburg virus disease, and Crimean-Congo haemorrhagic fever. There is no evidence of person-to-person transmission. That had led researchers to suspect a mixed arbovirus outbreak, according to WHO.
Trevor Shoemaker is an epidemiologist with the US Centers for Disease Control and Prevention's (CDC) Viral Special Pathogens Branch and until recently was stationed at the Uganda Virus Research Institute (UVRI), one of three laboratories where samples were sent for testing. He said it was unsurprising that an initial round of tests was inconclusive.
“It doesn't mean there wasn't an infectious cause”, he said. “It just means it was really hard to identify what was causing it.” This situation is not an uncommon scenario. The cause of an outbreak in the Darfur region of Sudan that killed 120 people between August and September, 2015, is still unknown. Darfur borders the area of South Sudan currently reporting cases, although it is unclear whether the two incidents are related.
Because some of the samples UVRI received from the current outbreak did test positive for malaria and chikungunya virus, both mosquito-borne illnesses, Shoemaker said it made sense to suspect an arbovirus.
“When you get these large emergences of mosquitoes and mosquito-borne illnesses, a lot of people getting sick at the same time, then you have that suspicion”, he said.