My latest update regarding the history of the Ebola epidemic can be found here:
August 26, 2014
The number of Ebola cases is growing exponentially. Using two methods, the cumulative number of cases is extrapolated based on the growth trend of the epidemic. If the disease continues to grow unchecked, the extrapolation shows the cumulative number of Ebola cases might grow to one million cases within six months, and one billion cases within twelve to eighteen months.
Forecasting the 2014 Ebola Outbreak
[Counting Days from May 23, 2014.]
December 17, 2014:
The exponential growth rate of the Ebola epidemic continued for about two months after my original blog post. The exponential trend was broken in mid-October, 2014, thanks to global relief efforts and effective public health programs in the affected countries. Updates to my original charts can be found here:
Additional resources may be found at StopEbola.uk:
Obsolete as of November 7, 2014, see latest post.
Update, October 31, 2014
Here are key charts from this post, with data from WHO updated through October 25.
In the October 29 report, WHO presents revised figures that add about 3700 cases to the previous total. These cases were recognized through study of patient databases, and occurred throughout the epidemic period, and not only since October 22. The additional cases return the cumulative case number to my original exponential extrapolation, first presented on August 26th.
It is uncertain whether the apparent flattening of the cumulative cases, observed through the month of October, is real or the result of under-reporting. Case reporting is increasingly late, and WHO cites data missing for a number of dates.
I have now seen two anecdotal reports that give a more optimistic appraisal of the situation in Monrovia, indicating fewer patients are reporting to Ebola clinics, and fewer bodies are being collected from the city outside the clinics. Authorities disagree on whether the drop in patients shows a real decline in the epidemic, or avoidance of the clinics.
Update, October 10, 2014
Reported data from Liberia show a falling number of new cases; however, the WHO and CDC believe that the situation continues to deteriorate. Since early September, official data from Liberia have been late, contradictory, and inconsistent. WHO and CDC believe there is substantial under-reporting of new cases. At best, there are only about 25% of the number of beds required in treatment centers. After weeks of seeing patients turned away from treatment centers, it seems likely that families are now caring for victims at home, causing under-reporting of official cases -- and transmitting the disease to new victims.
Update, October 27, 2014
Here are key charts from this post, with data from WHO updated through October 18. The latest point is the first point to fall below my original extrapolation.
The trend of officially reported cases has flattened, showing a reduced rate of transmission. But the trend must be taken with a grain of salt, considering anecdotal evidence for many unreported cases.
New case numbers from Liberia continue to be delivered much later than data from Guinea and Sierra Leone. I am interpolating numbers from Guinea and Sierra Leone to obtain a consistent single reporting data for the epidemic.
I found one anecdotal report from Monrovia which is cautiously optimistic. The report appeared on the website AllAfrica.com:
WHO continues to say that the situation is deteriorating in Liberia and Sierra Leone.
Updates with additional text can be found below.
I posted an update with text on September 15. I tweaked the models and looked at some of the containment efforts and procedures.
The post also discusses the accuracy of the case count from Liberia, the number of beds needed in West Africa, and the trend of the mortality rate.
Copyright 2014, Doug Robbins
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