Scott Edmunds

**[![author](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/author.jpg){.alignleft
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height="150"
srcset="http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/author.jpg 150w, http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/author-100x100.jpg 100w"
sizes="(max-width: 150px) 100vw, 150px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/author.jpg)Following
from his [guest
blog](http://blogs.biomedcentral.com/gigablog/2014/10/27/guest-blog-the-2014-ebola-epidemic-approaches-and-resources-to-slow-the-spread-of-infection/) in
October on "Approaches and resources to slow the spread of
infection", [Michael Dean](https://ccr.cancer.gov/michael-dean) from the
Center of Cancer Research at the NIH uses his data oriented approach to
give an update of where the Ebola epidemic is. While there may be less
media coverage (apart from [in the
UK](http://www.bbc.co.uk/news/health-30825231)), this doesn't relate to
the situation on the ground. Michael again has pooled together various
available data from the CDC and beyond to present a non-specialist view
of the pandemic status, comparing his and others predictions of where we
would be in 2015, if the spread of the disease is finally under control,
and lessons for the future. \[Note: the material presented here is from
Michael Dean's own perspective and does not represent the viewpoint of
the NIH, or NCI.\]**

At the time of the [first
installment](http://blogs.biomedcentral.com/gigablog/2014/10/27/guest-blog-the-2014-ebola-epidemic-approaches-and-resources-to-slow-the-spread-of-infection/) of
this blog in October, the Ebola Epidemic of 2014 was headed for
potential international disaster, and was correctly called "... the most
severe, acute health emergency seen in modern times". Infections
appeared to be increasing logarithmically and experts at the CDC and
elsewhere projected as many as 1 million cases by the years end
\[[1](http://www.cdc.gov/mmwr/preview/mmwrhtml/su6303a1.htm?s_cid=su6303a1_w)\].
A massive international effort was underway to employ resources to
reduce transmission, improve testing and provide medical care for
infected individuals
\[[2](http://www.nejm.org/doi/full/10.1056/NEJMoa1411100)\]. A
multi-disciplinary approach was clearly needed to improve the situation
move towards a total eradication.

[![Fig
1](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1.png){.aligncenter
.wp-image-1416 .size-full loading="lazy" decoding="async" width="600"
height="600"
srcset="http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1.png 600w, http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1-150x150.png 150w, http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1-300x300.png 300w, http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1-100x100.png 100w"
sizes="(max-width: 600px) 100vw, 600px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-1.png)

Figure 1. Map of Ebola cases in Western Africa. From WHO Situation
Report, Dec. 24, 2014.

Remarkable progress has been achieved, and the WHO targets of 100% safe
burial, 100% of patients in treatment facilities, universal access to 24
hour viral testing and 100% daily tracing of all registered contacts by
the end of 2014 had [largely been
met](http://www.who.int/csr/disease/ebola/situation-reports/archive/en).
There are over 220 safe burial teams, 80% of the projected need, and
sufficient to bury all documented cases in the three most effected
countries (Liberia, Sierra Leone and Guinea).

An effort to construct Ebola Treatment Centers (ETCs); 20 to 200 bed
facilities and Community Care Centers (CCCs, 8 to 30 beds) has enabled
isolation and treatment to be carried out in both intense transmission
areas as well as newly arising rural hot zones. There are now between 2
and 9 beds/documented or suspected case in Western Africa. In addition,
all districts in the three countries have access to Ebola testing within
24 hours to allow rapid release of suspected cases that are indeed
negative. The critical goal of daily monitoring of every registered
contact is now 96-99% achieved.

Lastly, extensive educational efforts have reached religious and
community leaders in nearly every district to aid in education of the
population, early detection of newly suspected cases, coordination of
burial practices consistent with local beliefs and cooperation in the
placement and use of CCCs and ETCs.

The result of all these efforts have achieved a reduction in the
Replication Rate (R0) to near 1
\[[3](http://www.nejm.org/doi/full/10.1056/NEJMc1414992)\]. Surprisingly
this reduction in R0 was achieved in September and has remained at this
level, and declining below 1 in Liberia. The factors leading to the
reduction in transmission are not clear, but it may be that the viral
load of Ebola is very high in the late stages of disease, and so safe
burial, and rapid isolation of cases are particularly important.

**Liberia**  
The most dramatic progress has been achieved in Liberia, the site of the
highest number of cases (almost 50% of all cases) and an estimated
doubling rate of 24 days at the end of August. Liberia now has reduced
to 60-80 new cases per week and an estimated doubling time of 180-240
days. Newly reported cases have been steadily declining since
mid-November in the country as well as in the Montserrado district, the
most affected area.

[![Table
1](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Table-1.jpg){.aligncenter
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height="189"
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sizes="(max-width: 600px) 100vw, 600px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Table-1.jpg)

**Sierra Leone and Guinea**  
The numbers of new cases and the resulting estimated doubling rates show
the epidemic continues to be intense in these two countries that now
drive the overall epidemic. Guinea had 120-180 new cases in each of the
last three weeks of December and Sierra Leone has reported 450-650
cases/week for each of the last four weeks. Both countries have multiple
districts with intense transmission including new areas emerging in the
last month.

[![Table
2](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Table-2.jpg){.aligncenter
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sizes="(max-width: 600px) 100vw, 600px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Table-2.jpg)

**Modelling cases and mortalities**  
By modeling the data from 8/29/2014 to date the cumulative cases in
Liberia best fits a 2-factor polynomial function and would predict that
the epidemic will continue to level off and be contained. However as
this epidemic has demonstrated in the past, until there are no new cases
in a country for at least 21 days, victory cannot be claimed. And the
extensive presence of intense transmission areas bordering Liberia
continues to pose a threat.

[![Fig 2 &
3](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-2-31.jpg){.aligncenter
.wp-image-1419 .size-full loading="lazy" decoding="async" width="600"
height="450"
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sizes="(max-width: 600px) 100vw, 600px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig-2-31.jpg)

Figure 2. Cumulative Ebola cases and deaths. Figure 3. Cumulative Ebola
cases in Liberia fit to a 2 factor polynomial function with a R\^2
=0.97.

Sierra Leone and Guinea appear to still be in linear phases of
transmission. It is expected that the same practices that have reduced
transmission in Liberia will show results in these two counties in the
near future.

[0.98." border="0″ height="450″
width="601″\>](http://blogs.biomedcentral.com/gigablog/files/2015/01/Slide11-e1421280667331.jpg)

[![Fig.
4](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig.-4.jpg){.aligncenter
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sizes="(max-width: 600px) 100vw, 600px"}](http://gigasciencejournal.com/blog/wp-content/uploads/2015/01/Fig.-4.jpg)

Figure 4. Cumulative Ebola cases in Sierra Leone and Guinea fit to log
and 2 factor polynomial functions with a R\^2 \>0.98.

**Lessons going forward.**  
The last two months have seen dramatic gains in the establishment of
concrete goals, mobilization of resources, and implementation to contain
the Ebola epidemic. Particularly impressive has been the coordination of
national, international and non-governmental bodies. [While Doctors
Without Borders/Médecins Sans Frontières
(MSF)](http://www.msf.org/) and [Samaritan's
Purse](http://www.samaritans-purse.org.uk/) were leading charities
providing care,[The International Federation of Red Cross and Red
Crescent Societies (IFRC)](http://www.ifrc.org/) have been leaders in
implementing safe burials, [Global
Communities](http://www.globalcommunities.org/) (Liberia) and [Concern
Worldwide](https://www.concern.net/en/) (Liberia and Sierra Leone),
and [World Vision](http://www.worldvision.org/) (Sierra Leone) have made
major contributions and [UNICEF](http://www.unicef.org/) has led much of
the education efforts. The coordination by WHO of the efforts of the
CDC, USIAD, British, Cuban and French efforts as well as the collection
and distribution of funds and supplies from international and private
donors is commendable. It is hoped that this epidemic will lead to
lasting, improved international surveillance and early treatment of
future epidemics of all kinds. It is also clear that the coordinated
application of medicine, public health, epidemiology, virology,
biotechnology, sociology and anthropology has been essential to rapidly
understand and begin to address the many complex facets of this
epidemic.

**For animations and interactive maps see
the [NEJM](http://www.nejm.org/doi/full/10.1056/NEJMc1414992) and[ WHO
interactive
map](http://maps.who.int/SimpleViewer_WHO/?appid=c932f6aca33242d8b160f653cc8e2d7a).
Up to date numbers and visualisations can also be found
on [Healthmap.org](http://www.healthmap.org/ebola/#timeline) and [VDU](http://virologydownunder.blogspot.com.au/2014/07/ebola-virus-disease-evd-2014-west.html).**

### **References**

1\. Meltzer MI, Atkins CY, Santibanez S, Knust B, Petersen BW, Ervin ED
et al. Estimating the future number of cases in the ebola epidemic ---
liberia and sierra leone, 2014-2015. Morbidity and mortality weekly
report [*Surveillance summaries*.
2014;**63**:1-14. ](http://www.cdc.gov/mmwr/preview/mmwrhtml/su6303a1.htm?s_cid=su6303a1_w)  
2. Team WHOER. Ebola virus disease in West Africa--the first 9 months of
the epidemic and forward projections. *The New England journal of
medicine*.
2014;**371**(16):1481-95.[doi:10.1056/NEJMoa1411100](http://www.nejm.org/doi/full/10.1056/NEJMoa1411100).  
3. Team WHOER. West African Ebola Epidemic after One Year -- Slowing but
Not Yet under Control. The *New England journal of medicine*.
2014. [doi:10.1056/NEJMc1414992](http://www.nejm.org/doi/full/10.1056/NEJMc1414992).

The post [Guest Blog: The Ebola Epidemic revisited -- where are we in
2015?](http://gigasciencejournal.com/blog/guest-blog-the-ebola-epidemic-revisited-where-are-we-in-2015/){rel="nofollow"}
appeared first on
[GigaBlog](http://gigasciencejournal.com/blog){rel="nofollow"}.


<strong>
 Following from his guest blog in October on “Approaches and resources to slow the spread of infection”, Michael Dean from the Center of Cancer Research at the NIH uses his data oriented approach to give an update of where the Ebola epidemic is. While there may be less media coverage (apart from in the UK), this doesn’t relate to the situation on the ground.
</strong>

Messaggi di Rogue Scholar

Guest Blog: The Ebola Epidemic revisited – where are we in 2015?