Vienna - Ebola is one of the most lethal viruses to have sparked an epidemic in recent history. As countries struggle to contain outbreaks, the lessons of containing contagions are being driven home once again.
The first case of Ebola in the current outbreak is widely believed by epidemiologists to have been a baby boy last December in Meliandou, in the depths of the Guinean jungle.
Within four days of getting sick, the boy was dead.
And, as his family members cared for him and sought medical help, the virus spread. By February, an infected nurse reached Gueckedou, an important merchant hub where traders from Sierra Leone, Liberia and Guinea assemble.
It wasn't until August that the World Health Organisation (WHO) said the death toll had reached 1 000 and declared a state of emergency. The most recent figures put the caseload at 17 908 and the death toll at 6 373 in West Africa.
This time lag, for which the WHO has been criticised, has been pinpointed by many as the turning point, when the viral outbreak became a pandemic.
“If you respond to these outbreaks when and where they are detected - and this would have been in March of this year - before they have spread widely, most times you can stop them while they're still rural,” David Heymann, professor of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine, told dpa.
As an epidemiologist with the US Centers for Disease Control and Prevention (CDC), Heymann was part of a team that investigated some of the first Ebola outbreaks in sub-Saharan Africa in the 1970s.
He pointed out that there have been at least 20 outbreaks of Ebola in the past. But none of them exploded to the level of the current one.
Amesh Adalja, a senior associate at the University of Pittsburgh's Centre for Health Security, said one of the reasons the current outbreak is so severe is that it erupted in an area unaccustomed to Ebola. Most outbreaks have occurred in central Africa, especially in the Congo.
“People underappreciated how difficult it would be to implement an infrastructure to deal with Ebola,” Adalja told dpa. “People didn't realise the special problems this area has: a border region already under distress. The virus is the same, the control measures are the same, but it was harder to implement those measure because these countries hadn't dealt with something like this before.”
With many global health scares, governments scramble to protect their citizens and find ways to detect contagions before they broaden and become epidemics. After an outbreak of Severe Acute Respiratory Syndrome (SARS) in China in 2002, governments around the world promised to fortify national health surveillance and response systems.
However, many countries did not follow through, including the ones in West Africa.
“So now, will this again be an opportunity where everybody is mobilised and worried, and then it fades later on? Let's hope not,” Heymann said.
In the US, some viruses - including Ebola - were put on government biosecurity lists as possible terrorist weapons, which jump-started investment in vaccine research. Adlaja said that without those investments, there would have been even less progress on Ebola vaccines than was seen when this outbreak began.
But it's impossible to develop vaccines for every potential virus. In most cases, the surest way to save lives is to ensure that viruses are contained in the first place.
“We have to minimise the element of surprise,” Adalja said. “There were cases in the beginning of this epidemic where someone would die and people didn't know what the cause was. We can't be satisfied with saying there was an unknown viral disease - when there's something unexplained it has to be narrowed down until there's an explanation.”
In many cases, that means keeping track of what's normal in a region, in order to detect any unexplained outbreaks that are a deviation from the norm.
“If you get the right system, it'll detect any epidemic,” Heymann said. “So that's what we need to do, make sure that these systems are in place. What is important is that countries themselves can detect and respond to these outbreaks.”
Heymann pointed to Ebola cases in Nigeria, Mali and Senegal, where health systems sprang into action and contained the possibility of further infection.
At a conference at WHO headquarters, Liberia's chief medical officer, Bernice Dahn, said her country has already started a discussion on strengthening the health system.
“We are in the process of thinking post-Ebola,” she said.
Sierra Leone's Health Minister Abu Bakarr Fofanah stresses that the international health system is only as strong as its weakest link.
“In the absence of a strong, resilient health system in just one country (...) it can rapidly become an epidemic, and even a pandemic,” he said. - Sapa-dpa