Twenty-one days: the maximum incubation period for Ebola Virus Disease. That means if you have come into contact with the virus but have no symptoms by day twenty two, then you are clear.

Forty two days: the incubation period x 2, and the period it takes for a country to be officially considered clear of the disease. If no new suspected cases are reported for 42 days, the outbreak is over.

Today, Wednesday 13th August 2014, is a big day for me ... it has been twenty-one days since I left Liberia, and for the first time I know beyond a doubt that I am Ebola-free. Not everyone is so lucky. In my first 14 days of incubation in the comfort of my Southampton home, the number of cases in Liberia more than doubled from 249 on 23rd July to 554 on 6th August. Of these cases, 294 people had died. The country is in a state of emergency, schools are closed, roads are blocked, communities are quarantined and attempts to bring the disease under control are being crippled by widespread fear.

So for another 21 days I am going to write a blog post every day to raise awareness of the grim challenge confronting Liberians, and to raise funds to support the Red Cross, who I work with collaboratively in my normal life as a PhD social researcher, and who are at the front line fighting the worst known Ebola outbreak in history.

Tuesday 19 August 2014

Where has all the ZMapp gone?

After two American aid workers, one Spanish priest, one Nigerian and two Liberian doctors have been treated with ZMapp, there has so far been just one death – 1/6 is good odds in this Ebola outbreak.  So why can’t more people be treated with this promising drug?  Well … because there is none.  And there won’t be any more for a few months.  This is not a limitation that is exclusive to ZMapp – we can expect other drugs to be limited in their availability to meet demand.  So why is that?

Sad but true, the bottom line is cost.  It takes a lot of money to go through the process to develop and test new drugs, and someone has to pay for that.  The immense costs associated with developing and trialling drugs either comes through grants or is met by pharmaceutical companies who will make a long-term profit gain if the drug is successful.  In order to make a business case for this process, either grant-funders or commercial organisations need to see a return on investment.  But previous outbreaks have been small and contained – there simply have not been that many Ebola cases in the past, certainly not enough to justify more than a modest investment, horrible though the consequences are for those that are infected.  So the money has not flowed in, the early development work has been slow, and the drugs are not ready to cope with this unprecedented level of demand.

Secondly, it’s easy for non-specialists like me to imagine someone just has to turn on a machine in order to pump out whatever synthetic products go into these drugs – but I understand it’s not like that.  Taking ZMapp as an example, manufacturers Mapp Bio explain that the humanised antibody proteins that make up the drug are grown using a low-nicotine tobacco plant as a host.  Once the plants mature, they are harvested and the antibody proteins need to be extracted, purified and tested before they can be made into a drug.  This is not a process of pulling a lever, it takes time to grow the basic components of the drug.  No matter how eager organisations may be to invest in this process now, it still takes as long as a tobacco plant to grow before you get any results.


Finally, in order for a drug to be produced on any significant scale it needs to be licenced, which means it first has to go through a clinical trial.  Clinical trials happen in a number of stages – the first stage tests the drug for safety using up to 100 health volunteers.  That is achievable – if the drug is produced.  Health volunteers are relatively easy to come by.  But the second, third and fourth stages of the trial require larger numbers of ill people, because they are not testing only the safety of the drug, but also the effectiveness of the drug in treating the disease it is designed to treat.  To conduct a phase two trial, usually several hundred people will be involved.  The problem with Ebola is, you only have these people available in the context of an outbreak, and no one knows when or where an outbreak may take place.  There is no precedent to the scale of this outbreak – there have already been more than five times the number of cases that any previous outbreak of any Ebola strain has accumulated.  This outbreak could provide a sufficient number of cases for a clinical trial to progress – but no one could ever have known to be prepared.

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