Date: 27 Oct 2014, Science, Technology and Culture
Question setter: John Karslake


Will the number of Ebola cases outside Africa exceed 150 by the end of November 2014?


Answer: No
Confidence level: 35%
Mean confidence level (all requests): 51.75%

The incidence of ebola cases outside Africa has remained very low so far, considering how rampant it has been in the three nations where the outbreak is worst. There has been a huge increase in awareness in the last few weeks and this is likely to restrict travel on the one hand and reduce the spread of infection in other countries on the other. Even when health workers are infected and evacuated, the level of precautions now make further spread from treatment at home very rare. Many deplore the lack of swift response from richer states to combat the disease in West Africa. In spite of this, the statistics show that the numbers of new cases are leveling off. We wait to see if this more encouraging trend continues but it bodes better for restricting the export of the virus. For the number of outside cases to exceed 150 by the end of November, it will need late recognition of imported cases and / or careless handling of those patients and those in contact with them. It would imply travel to countries with very low levels of preparedness. This is possible but unlikely. Although the cumulative number of cases outside Africa will probably eventually pass 150 this may not be until the end of the year, at the earliest.

Outcome: No
Score: 35
Mean score (all respondents): 28.00

Expert opinion:

Answer: Yes

Selected Expert Answer from Tim Edwards:
The WHO puts the global number of cases in the Ebola outbreak at over 10,000 before the end of October. Though less than 30 of these are outside the epicentre, the epidemiology of the disease in Africa suggests the feed-stock of sufferers is expanding. The political and healthcare systems in the most stricken countries cannot cope with epidemics. The response from the outside world has been too slow and too restricted to change that markedly yet for the control of Ebola. Numbers of facilities are improving but the number of health workers is utterly in adequate. Add to that the rather slow and incredulous political response at the borders of some countries, we will get many more infected people arriving unidentified. The result will be that they spread the virus with some they come into contact with, and as a consequence of all that there will be pockets of outbreak in several countries outside Africa. It is unlikely that the total number of cases in the rest of the world will remain below 150 in a month's time.

Answer: Yes

Selected Expert Answer from John Karslake:
The rampant spread of Ebola in three African countries make it probable that infections will leach out of Africa in the low hundreds. There have now been over 10k confirmed cases. Now, numbers of new cases seem to be flattening out in the bell-shape curve predicted by Farr's Law on epidemics. The wildest predictions of future spread are likely to be exaggerated but there is still plenty of the virus around. Help from the outside is being stepped up and that increase in personnel will boost the numbers of medical repatriations, one of the main reasons that cases outside Africa will top 150 over the coming month. The next few weeks is the most dangerous, combining new aid workers with the peak of new cases. In addition there will be some imported cases and still some infections passed to people in contact in outside countries. Monitoring of incoming passengers will result in isolation, not refusal of entry so those ebola patient numbers will be registered in the receiving country.
There is better understanding of the disease now and many places are well prepared to deal with it but that is not going to be enough to keep cases outside Africa below 150 and probably that figure will even be reached by the end of November.

Answer: No

Selected Expert Answer from Mettletest Panellist:
The number of confirmed cases in West Africa has passed the 10,000 mark and the real number may be much more than that. Nevertheless, the numbers outside Africa have been very small, to date. There will, no doubt, be more. I would expect these to remain low though. Controls at the borders of the worst affected countries will prevent travel for some at risk individuals. The training and protection of incoming health workers has improved, so they are less likely to be infected. This will help suppress the numbers of imported cases outside Africa. When infected patients do move afield, procedures to prevent further spread have been well rehearsed in many countries. Greater numbers of non-African health workers will mean more medical evacuations but this will not be enough to push numbers above 150 by the end of November. A larger figure will eventually be reached, before the outbreak is fully dealt with, but that may well be into 2015.

Outcome: No

Comment on outcome from Mettletest Panellist:
It is remarkable that the number of cases outside Africa have been restricted to the low twenties. There has been a large (if inadequate) response from outside the region but few medical evacuations of the aid staff. (Mercifully, most of the evacuees recovered.) The low figures for the geographical spread are despite the cumulative number of infected people in West Africa rising to 16,000 with c.7000 deaths by the end of November 2014. The UN has warned that there is still a huge risk of the disease spreading to other parts of the world.