The identification of Patient Zero, also referred to as the index case in any viral disease, especially one of epidemic proportions is crucial in epidemiology. Honing in on the very origins of the disease allows epidemiologists to accurately track the geographical spread of the disease, as well as the means of contagion.

Yet another extremely important function of the hunt for Patient Zero has also been the recent advent of trying to find a vaccine to protect against the virus. Particularly in the case of viruses that are ever-changing, no matter the rate, tracing the disease back to it’s original form in humans allows researchers to be able to compare the current virus to its ancestral form, and consequentially gauge the effectiveness of a possible treatment.

Epidemiologists have traced the root of the most recent Ebola outbreak to a two-year-old boy in the Guinean city of Meliandou, of the Guéckédou province. The boy passed away on Dec. 6, 2013, just four days after presenting with symptoms of fever, black stools and vomiting. Seven days following his death, his mother passed away of the virus, after which his three-year-old sister contracted the virus on Christmas Day, passing away before New Year’s Day, shortly after which, the grandmother passed as well.

It is suspected that two mourners at the grandmother’s funeral contracted the virus from close contact and took it home to their village. A health worker who treated her carried it to his own village, killing both him and his doctor, who both were expected to have infected relatives from other towns.

The province of Guéckédou lies adjacent to both the Liberian border as well as the Sierra Leone, in an area that has most recently been the site of cross-border development, with amplified transport between the nations. The three nations are the poorest in the world, and hence have struggling healthcare systems being in a state of recovery from a history of political and civil turmoil. As a result, the virus had ample opportunity to spread throughout the region long before local health officials were even able to identify it in March of this year, let alone track it. 

While Africa is not new to outbreaks of the Ebola virus, the disease is new to the rapidly modernizing region and subsequently has grown to become the worst ever recorded in history, with 1779 individuals infected, and 961 in the nine months since the index case. Experts from Doctors Without Borders and the World Health Organization say the numbers could reach so far as to surpass records from all 24 Ebola outbreaks combined, meaning that it could take an indefinite number of months to fight it. In the face of the immensely overwhelmed regional healthcare systems, there is additional fear that the death toll could rise further with resources being re-allocated to Ebola care from the treatment of other diseases like malaria and dysentery.