Ebola vaccines in the works, but there's no simple way to test one
As experts argue about how best to proceed, WHO vows it will try to bring down to 'a matter of months' testing that can take four years
The popular instinct about the potential of vaccines to address the horrific Ebola outbreak in West Africa is: Why delay? If there's any chance they'll work, let's get them out now.
Unfortunately, things aren't that simple. That was made clear during an emergency conference convened by the World Health Organisation at the end of September to address this very issue.
The meeting brought together 70 experts - epidemiologists, public health regulators, pharmaceutical company representatives and ethicists, among others - to thrash out the right way to proceed with trials of two vaccines that have shown the most promise in private and first-phase human trials.
However, it underscored the special difficulties of testing a vaccine in the teeth of an ongoing outbreak for which no other remedies are in the offing. What emerged were sharp disagreements over the ethics of some testing strategies, such as random trials in which some subjects would receive an Ebola vaccine and a control group would receive some other medicine.
Most participants seemed to agree with the WHO's recommendation, which is to move almost immediately to phase III tests of the vaccines' efficacy in Liberia, Guinea and Sierra Leone, the outbreak's epicentre.
US officials last week asked three advanced biology laboratories to submit plans for producing the experimental Ebola drug ZMapp, which ran out after it was given to a handful of medical workers who contracted the disease in West Africa, government and lab officials said.