After the many cases of Ebola which appeared during such a short period, the situation appears to suddenly calm down, especially in West Africa, motivating experts to wonder if the virus is now undetectably immunizing some people, while still affecting and killing their loved ones.
Even though other health epidemics also had their share of “asymptomatic” cases – people exposed to the virus who do not get sick or show any symptoms – scientists’ opinions are divided. More research is needed for them to be able bump up the possible Ebola immunization to more than wishful thinking.
Furthermore, is recent studies prove to be right, immune people might be the key answer to ending the Ebola outbreak much faster, sparing thousands of more deaths. The people who have been exposed to the virus and did not contract the disease would be studied and their secret protection could be transferred to the suffering cases.
Philippe Maughan, senior chief of the European Commission, is hoping that something called “herd immunity” is slowly showing its effects – a large number of people immune to the virus, stopping the advance of the epidemic, creating an environment where the disease cannot find any more organisms to infect.
Even though the World Health Organization did not perform very well at the first-response operation of the epidemic, their latest reports finally delivered good news: the number of new infected people in West Africa had decreased dramatically in countries like Guinea, Sierra Leone and especially in Liberia.
These results are mostly accounted for by the drastic control measures which reduced contact between contagious patients or corpses and healthy people, but some experts still hope other factors might be at work.
The herd immunity is a characteristic found in many contagious diseases, sort of a built-in fighting mechanism, which slows down the epidemic, once enough people acquired protective antibodies. This so-called “sub-clinical cases” were documented during different outbreaks, whether it was flu, measles or polio.
But some experts, such as David Heymann, chief of global health security at Chatham House, are rather suspicious about whether the phenomenon is actually happening in the case of the Ebola outbreak, in particular, or even in the case of any epidemic, in general. Although the latest numbers show that the new cases are less severe, and there have also been discovered asymptomatic persons, there is a huge step between the current situation and the large-scale phenomenon of herd immunity. In the meantime, the best term we could be using, according to Heymann, is household immunity in development, bearing in mind that even this possibility is still just theoretical.
On the other hand, there are more hopeful scientists who are interested in research in West Africa, searching and testing possible immunization cases, with the sole purpose of finding the secret of their resistance to the virus.
The success of such research would help not only in slowing down the spreading of the outbreak, but it would also provide immune people who could take over the disease-control operations. Professor Steve Bellan of the University of Texas thinks they could assume positions which involve close contact with contagious patients, such as caring for the suffering and conducting burials, which are highly risky jobs.
Bellan is basing his theories on the results provided by two studies. One of them observed the Ebola outbreak in 1997 in Gabon, showing a striking 71 percent of the “seropositive” people did not contract the disease. Also, the second study, which became public in April 2002, showed that 46 percent of the people who lived with an Ebola patient were also seropositive – characteristic of people with the virus in their blood.
It is understandable that the main focus of the medical efforts directed for the Ebola epidemic was to help the sick and dying, not necessarily to test people who did not present symptoms. This Ebola outbreak is on record the largest storming the three poorest Africa countries, leaving a lot of corpses and suffering families behind it.
One of the most hopeful cases for studying the seropositive condition in healthy people is a Guinean student, who has travelled to Senegal without infecting any other people, despite making direct contact with many. He is one of the few current hopes in finding the right antibodies for stopping Ebola.
Ian MacKay, a virologist from Australia, is of the opinion that epidemics are full of mysteries yet unknown to the medical staff, and that silent immunization for Ebola might just be one of those. The current outbreak is proof that contagious diseases are rather full of questions and few answers, and shows how each virus has many things it might teach us, and help us improve medical solutions for the future.
Image Source: NPR