Ebola outbreak confirmed in Democratic Republic of Congo

I mentioned in this post on Marburg virus that another outbreak of hemorrhagic fever had been reported in the Democratic Republic of Congo (DRC, formerly Zaire). It's now been officially reported by labs in Congo and Gabon that, indeed, this new outbreak is due to the Ebola virus. More on this after the jump.

As I've written previously, the DRC has been especially hard-hit by filovirus outbreaks. This was one of the places where Ebola first made its appearance in the human population, and was also the site of large outbreaks of the virus in 1995 and 2001 (with another Marburg outbreak in the middle of those two). Collectively these outbreaks already account for well over 800 cases of filoviral disease, and the ongoing epidemic appears to have driven that number up by 50%:

Provincial chief medical inspector Jean-Constatin Kanow says more than 160 people have died of the illness in the affected region since late August and nearly 400 have been infected.

He says the infections are mostly in two areas, Mweka and Luebo and the majority of the deaths ocurred at the beginning of the outbreak.

Makwenge did not say whether the outbreak has been contained.

That's a huge number of cases in such a short amount of time, and it seems unlikely that it's under control (if it was contained, they would have said as much).

The outbreak began in a typical manner. Likely one or more people became ill with the virus (the index case or cases). In this situation, they mention the funerals of two village chiefs in the region. It is often custom in these areas for family members to ritually wash the bodies after death--thereby coming into contact with large amounts of highly infectious body fluids and tissues. This probably triggered the epidemic here, which then amplified when the secondary cases (those infected by the index case(s)) died as well.

In some instances hospitals have acted as amplilfiers of the outbreak, spreading the illness via contaminated needles or poor hygienic practices within the hospital itself. As I mentioned in the earlier post, the medical situation in the DRC is abysmal: in 2001, an Oxfam report estimated that there were only 2,056 doctors for a population of 50 million, and of these, 930 are in Kinshasa (the capital and largest city).

We still aren't 100% sure of the reservoir for Ebola, and the article doesn't mention how the index case(s) may have been infected. Like Marburg, Ebola has now been detected in wild fruit bats, and some outbreaks have been tied to bat exposure in humans, so it's possible the virus is directly transmitted this way. In other cases, a non-human primate may act as an intermediate between the natural reservoir and the human population, as other outbreaks have been associated with butchering and eating bushmeat, including chimpanzees.

I'm sure there will be more information forthcoming as medical workers and epidemiologists enter the region and work to assess the situation. As it stands, the article reports that four villages are affected, with 103 deaths out of 217 confirmed cases just by the end of August (and by the numbers early in the article, apparently an extra ~50 deaths and almost 200 additional cases this month alone). I don't have any information yet regarding identification of the strain of virus, but from the numbers it seems unlikely to be the Zaire strain that's hit DRC in the past (typically causing upwards off 80% mortality).

[Update: this story notes that potentially Shigella cases are mingled with Ebola ones, making the total numbers and the mortality figures in doubt currently. Stay tuned for more as this gets sorted out...]