Random Analytica

After a six month sabbatical I’m dipping my toe back into Random Analytics (and by default my passion for amateur epidemiology).

Last week the World Health Organisation released its latest Ebola Situation Report – 15 July 2015 which has demonstrated that although the disease has stopped it momentous attrition within West Africa it hasn’t entirely gone away. As we learnt from the initial outbreak in late 2013 one case can turn into many hundreds, then many thousands and finally some tens of thousands in a very short space of time.

The WHO notes:

There were 30 confirmed cases of Ebola virus disease (EVD) reported in the week to 12 July: 13 in Guinea, 3 in Liberia, and 14 in Sierra Leone. Although the total number of confirmed cases is the same as the previous week, there has been a shift in the foci of transmission. For the first time in several months, most cases were reported from Conakry and Freetown, the capitals of Guinea and Sierra Leone, respectively. All 9 of the cases reported from Conakry and all 10 of the cases reported from Freetown were either registered contacts of a previous case or have an established epidemiological link to a known chain of transmission. One of the 30 cases reported in the week to 12 July arose from a yet unknown source of infection. However, a substantial proportion of cases (7 of 30: 23%) continue to be identified as EVD-positive only after post-mortem testing. This suggests that although improvements to case investigation are increasing our understanding of chains of transmission, contact tracing, which aims to minimise transmission by identifying symptoms among contacts at the earliest stage of infection, is still a challenge in several areas.

As the following chart demonstrates the 2013-15 West African Ebola Zaire outbreak has eclipsed all previous Ebola events.

Even as the disease has left the pages of most Western newspapers and television screens the scale of the event and the ongoing transmission is still frightening. Consider just these three data points:

1. Based on current Case Numbers alone the West African outbreak is 65-times greater than the next largest outbreak (the Ebola Sudan outbreak in Uganda in 2000);
2. The West African outbreak currently is 11-times greater than ALL previous outbreaks combined (total cases prior to the West African plus the 2014 DRC outbreak totalled 2470 while the current outbreak cases total 27,678);
3. In the past week of reporting the total case count (30) was just under half of the 10^th worst outbreak of Ebola recorded in Gabon back in 2001 and greater than the 13 of the 30 historical outbreaks/events across the world to date.

Not all of us have forgotten West Africa.

Data Sources

[1] WHO. Ebola Situation Report – 15 July 2015. Accessed 17 July 2015.

“We are pleased to say we have controlled the spread of the epidemic.” Francois Fall, Foreign Minister, Guinea (14 April 2014).

“First and foremost, I want the American people to know that our experts, here at the CDC and across our government, agree that the chances of an Ebola outbreak here in the United States are extremely low.” Barack Obama, President, United States of America (16 September 2014)

As the United States grapples with its first case of the Ebola Virus Disease (EVD) it is worth noting that the disease is ravaging West Africa causing thousands of deaths, destroying capabilities, causing starvation and reeking further economic devastation across one of the poorest regions in the world.

According to the World Health Organisation (WHO) which issued new data on the 1^st October 2014 the West African EVD outbreak, which is ongoing now has 7,178 clinical cases with 2,800 in past 21 days (39.1%); and 3,338 deaths (a provisional Case Fatality Rate or CFR of 46.5%). Health Care Workers who are the front-line workers in the fight against EVD are also overly represented in the casualty statistics. Currently there have been 377 clinical cases (5.3%) and 216 deaths (6.5%). The latest update does not include the new case which presented in the United States.

What started as a post-graduate project to build a five-minute Ebola Virus Disease (EVD) lesson utilising just five graphs and six-dot points has now turned into more than 20 charts and infographics.

Here is a look at four charts or infographics of EVD across Africa with WHO data confirmed to 28 September and where applicable will include the US case.

Ebola across Africa

The Ebola across Africa infographic details the country specific outbreaks of Ebola since it was first discovered in 1976 (with a 1972 retrospective case from Zaire included). When I first completed this infographic in April the bulk of the outbreaks of Ebola Zaire had occurred in Central Africa with the Democratic Republic of Congo being the country most impacted in terms of outbreaks, cases and deaths.

Three interesting data-points have occurred over the past half-year. The first data-point is the fact that the weight of Ebola Zaire cases has shifted from Central Africa to West Africa (and now includes Nigeria and Senegal as countries where the disease has exported itself to). The second point is while EVD ravages West Africa another unconnected outbreak has occurred in the DRC.

The last point I think is really interesting and not fully reflected in the infographic is the differential between health expenditure of those countries impacted by Ebola in Africa versus that spent in the United States. In Africa the impacted countries health expenditure per capita ranges from just $15 in the DRC to $96 in Sierra Leone, while in the United States the amount is $8,895.

Notes: The 1976 – 2004 outbreaks of Ebola Sudan occurred in the bottom half of Sudan (now South Sudan). Zaire was renamed the Democratic Republic of Congo in 1997. Health expenditure per capita is expressed in $USD and represents 2012 data.

Ebola (Top 10 Outbreaks by Case Numbers)

The first chart displays the top 10 outbreaks in order of case numbers. Each horizontal bar is filled with the flag(s) of the country where the outbreak occurred. In the case of the West African outbreak there are now six countries involved and the flags are in order sorted by number of cases.

With clinical cases now above 7,100 the West African outbreak has now become largest Ebola outbreak in history based on both case numbers (7,179) and fatalities (3,338). The second largest outbreak was of Ebola Sudan which occurred in Uganda (2000) when 425 became infected and 224 died.

Another couple of very interesting data-points. The first is the fact that the West African outbreak is the now the first to cross national land borders and the first to travel internationally out of Africa. The only other recording of an EVD that jumped borders prior to this outbreak was the Gabon/RSA (1996) outbreak. In that instance a doctor caught the disease in Gabon and subsequently took an international flight to South Africa where he became ill and infected other Health Care Workers (HCWs).

The second interesting point is the inclusion of the latest DRC outbreak. With 70-cases and 42-deaths recorded to date it has now moved into the 9^th largest outbreak by case numbers.

Ebola (Cases by Classification and Year)

The next chart shows cases by classification (in order they are Ebola Zaire, Sudan, Bundibugyo, Reston and Ivory Coast) by year, split into those recovered or those deceased (which follows in a red variant) and ordered from most impacted to least impacted year. Due to the severity of the latest outbreak I have removed 2014 as a column and included it as a separate pie chart.

The combined West African and DRC outbreaks has become the most significant in terms of case numbers by year, eclipsing the 1976 dual outbreaks (Zaire and Sudan) which saw 603 cases and 431 deaths (a combined Case Fatality Rate of 71.5%).

Notes: Several years had just one case. They are 1972 (a retrospective fatality of Ebola Zaire in Zaire), 1977 (a single case of Ebola Zaire in Zaire), 1988 (an accidental infection of Ebola Zaire in Porton Down, UK) and 2011 (a single fatality of Ebola Sudan in Uganda).

The West African Outbreak – Cases & Fatalities by Month

The final chart shows both case numbers and fatalities by month. Each column is split into the five impacted countries (the USA will most likely find its place with the October data). The data is visualised by the varying national flags.

The obvious data-point from the infographic is that the epidemic curve continues to increase month on month with data still outstanding for the 29^th and 30^th of September.

Summary

Over the past 24-hours a lot has been made of the first case reported from the United States. As much as that is bad news the disease is destroying several countries as we speak so I am hopeful that the attention the US case creates might mean more support for the countries that are currently doing it very tough.

Data Sources

[1] World Bank. Health expenditure per capita (current US$). Accessed 2 October 2014.
[2] World Health Organisation. WHO: Ebola Response Roadmap Situation Report 1 October 2014. Accessed 2 October 2014.

Yesterday I did a lengthy post on some of the Workforce Planning considerations that need to be considered in the fight against the Ebola Virus Disease (EVD) outbreak currently underway in West Africa. One of my key recommendations to those with an ability to elicit change was to put more focus on data-gaps in a range of key job roles, rather than just counting the HCW dead.

One of the issues that I discovered during my writing yesterday is that if I was a Workforce Planner working on the requirements of this outbreak I need to start to split my base level, or Hard-to-Fill (HtF) roles into another group. The new group would be defined as Hard-to-Replace (HtR) roles, which is a role that has become highly risk adverse to long lengths of medical treatment or fatality. The EVD outbreak has, to 14 September 2014 claimed more than 150 Health Care Worker lives and infected more than 300 including some of the Operationally Critical Job Roles (OCJR) in a region which was largely devoid of a depth of professional skill-sets, especially those with health training.

In response to the lack of publically sourced infographics in this space I thought I would complete something new which focussed on Health Care Workers. The term Health Care Workers is a Job Family and a very high level broad brush. It would be more relevant, given the loss of hundreds in this skill-set to start concentrating on how many Specialists, GPs and Nurses that we needed to replace.

That aside, the three most impact countries are Guinea, Sierra Leone and Liberia have lost more than 300 Health Care Workers to EVD in recent months. Here is an infographic to emphasise the losses on the ground:

Here is the data from the most recent update provided by the WHO:

In summary I would like to congratulate the WHO on their fantastic epidemiological data that comes out of their offices in what some are calling the worst health disaster in many generations. My main contention from my PeakJobs piece was to suggest the need for updating the global public, not only in the lagging indicators (such as the deaths of individuals or HCW’s) but to also emphasise the demand analysis side.

Demand analysis of recent losses and a massive surge in HCW resources in the fight against EVD will stop the outbreak, treat the infected more efficiently, assist with essential services (such as sanitation and logistics), preserve stability and prevent further outbreaks.

All the things that the UN suggested were possible with Resolution 2177.

Data Sources

[1] United Nations Security Council. With Spread of Ebola Outpacing Response, Security Council Adopts Resolution 2177 (2014) Urging Immediate Action, End to Isolation of Affected States. Accessed 20 September 2014.
[2] World Health Organisation. Ebola Response Roadmap: 28 August 2014. Pg. 5. Accessed 5 September 2014.

Here are three updated charts of the 2014 Ebola Virus Disease outbreak using a number of primary sources including the most recent World Health Organisation Disease Outbreak News (DON) released 4 September 2014 with data to the end of August. As new updates occur I try to update the charts and promulgate via Twitter.

***** Please note that all EVD infographics in this series were updated with public source information to 4 September 2014 *****

Ebola (Top 10 Outbreaks by Case Numbers)

The first chart displays the top 10 outbreaks in order of case numbers. Each horizontal bar is filled with the flag(s) of the country where the outbreak occurred. In the case of the West African outbreak there are now five countries involved and the flags are in number of cases order.

With clinical cases now reaching more than 3,700 the West African outbreak has now become largest Ebola outbreak in history based on both case numbers (3,707) and fatalities (1,848). The second largest outbreak was of Ebola Sudan which occurred in Uganda (2000) when 425 became infected and 224 died. The recent outbreak is the first to migrate across international land borders. The only other recording of an EVD that jumped borders prior to this outbreak was the Gabon/RSA (1996) outbreak. In that instance a doctor caught the disease in Gabon and subsequently took an international flight to South Africa where he became ill and infected other Health Care Workers (HCWs).

Ebola (Cases by Classification and Year)

The second chart shows cases by classification (in order they are Ebola Zaire, Sudan, Bundibugyo, Reston and Ivory Coast) by year and then split into those recovered or those deceased (which follows in a red variant). The combined West African and DRC outbreaks has become the most significant in terms of case numbers by year, eclipsing the 1976 dual outbreaks (Zaire and Sudan) which saw 603 cases and 431 deaths (a combined Case Fatality Rate of 71.5%).

On a side note I really need to re-organise this chart to display 2014 horizontally because the sheer size of the outbreak has destroyed any clarity of previous years. A project for next week.

Currently the provisional Western African outbreak has seen 3,760 cases and 1,861 deaths (a CFR of 49.5%).

Notes: Several years had just one case. They are 1972 (a retrospective fatality of Ebola Zaire in Zaire), 1977 (a single case of Ebola Zaire in Zaire), 1988 (an accidental infection of Ebola Zaire in Porton Down, UK) and 2011 (a single fatality of Ebola Sudan in Uganda).

The West African Outbreak – Cases & Fatalities by Month

The final chart shows both case numbers and fatalities by month. Each column is split into the five impacted countries with data visualised by the varying national flags.

Although I am only an amateur epidemiologist this has been a very telling chart and details how the epidemic curve has continued to increase over time. According to predictions by the World Health Organisation the outbreak may continue to grow and infect up to 20,000 persons so we are more than likely to see a further increase in both case and fatality numbers in September.

If you are interested in following this developing story I would suggest you follow/read Helen Branswell (Canadian health journalist for the in-depth stories) or Crawford Kilian and his excellent health related blog for all the big health related chatter including links to key Ebola persons and organisations.

For really good analysis and consistently updated charts in professional charting software (Tableau, Piktochart et al) I favour fellow Queensland Ian M. Mackay and on the other side of the Pacific pond, Maia Majumder. I do a range of other infographics (I like to think of them as data paintings) including analysis in the Flublogia space, when I find the time. My last health related piece was on Ebola in Sierra Leone.

Data Sources

[1] World Health Organisation. Ebola virus disease outbreak – west Africa: Disease Outbreak News – 4 September 2014. Accessed 5 September 2014.
[2] World Health Organisation. Ebola Response Roadmap: 28 August 2014. Pg. 5. Accessed 5 September 2014.