Case number changes between Ebola virus disease reports...

This is one of my favourite charts for following the Ebola virus disease outbreak in West Africa because it shows how things are changing from report to report. 

It plots the total number of suspected, probable and laboratory-confirmed cases between reports - which is a measure of change over time that is not cumulative.

That's not to say that understanding this chart is easy for everyone...as with everything, what you take away from it may be heavily influenced by your own perspective and your background in reading graphs. I have written something about how to read some of the graphs on my blog here, which may be helpful too.

Uses World Health Organization data up to and including the Situation Report from the 5th-Sept, 2014.
Click on chart to enlarge.

I've marked up the last three periods between reports to highlight that the time changes differently. You can see this for yourself if you look carefully at the horizontal or "x" axis (the one that has the dates) and look at where each dot lines up with its date. Some are further apart than others. 

You can also mouse over the dots on the interactive version of the graph here. That will tell you the dates. THe subtraction is up to you though!

The lines joining the dots here suggest what is happening between the WHO Reports, but the line do not actually use any real collected values...because we don't have them to plot. 

Technically, a bar graph would be more accurate, but I find a line graph easier to read at a glance. So do remember - we don't know what is happening between those dots. We're just presuming it.

Ebola: Blood, sweat and tears...

This post follows up the recent one on convalescent semen being able to harbour infectious Ebola virus (EBOV; although I am not aware of any infection resulting from this route of transmission there has been at least one report for Marburg virus [4]).

I thought I'd give the same treatment to tears and sweat which are also fluids intermittently listed as possible sources of EBOV infection for humans. Some examples of the scientific literature which support the risk messaging, follow.

Blood...

I think we are all pretty clear that the blood of an advanced case of Ebola virus disease (EVD) is heavily laden with virus and is the most serious of the risk factors for acquiring infection by an ebolavirus.

Viral loads (amount of virus in the sample) in blood can be above 10⁶-10⁸ plaque forming units or copies (pfu; a measure of infectious virus present using a lab test that measure the impact of virus on infected cells; copies measure viral genome and cannot prove infectious virus is present) per millilitre of blood in acute phase disease patients and non-human primates.[5,6]

Sweat...

There is not a lot on sweat containing signs of an ebolavirus.

• Bausch and colleagues found no trace of EBOV in a single acute sweat sample.[1]
• Jaax and colleagues found that in experimentally infected non-human primates (NHPs; rhesus macaques), that connective tissues next to hair follicles and sweat glands in the skin as well as the cells lining ducts of glands in the skin were sometimes positive for EBOV antigens (proteins).[2]
• Davis and colleagues infected NHPs (African green monkeys) and found signs of EBOV antigens in the cells lining the sweat gland ducts and in cells in the connective tissues next to hair follicles, but no virus particles by electron microscopy.[3]
• Zaki and colleagues found heavy signs of EBOV antigens (proteins) in the tissues around the sweat glands, but rarely also within sweat glands and ducts.[8] No virus particles were seen in the sweat glands or ducts when examined by electron microscopy.

Tears...

There is also very little I have found on this one.

• Bausch and colleagues found EBOV RNA in tears from 1 sample, but no infectious virus could be isolated.[1]
• Jaax and colleagues found some signs of virus in macrophages in the ciliary body of the eye of experimentally infected NHPs

Spit...

• Bausch and colleagues found infectious EBOV in 1 of 12 acute saliva samples (from 10 patients; none from 4 convalescent samples) and EBOV RNA in 8 of 12 (67%) of acute samples (none from convalescent samples).[1] RT-PCR positivity was significantly associated with fatal outcome.
• Formenty and colleagues found EBOV antigens and EBOV RNA in oral fluids from fatal cases and those who survived infection.[7]

References...

1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2395567/pdf/bullwho00439-0113.pdf
2. http://www.ncbi.nlm.nih.gov/pubmed/8712894
3. http://www.ncbi.nlm.nih.gov/pubmed/9278608
4. http://link.springer.com/article/10.1007/BF01734141
5. http://www.sciencemag.org/content/suppl/2014/08/27/science.1259657.DC1/Gire.SM.pdf
6. http://www.nature.com/nature/journal/vnfv/ncurrent/pdf/nature13777.pdf
7. http://www.ncbi.nlm.nih.gov/pubmed/16652308
8. http://www.ncbi.nlm.nih.gov/pubmed/9988163

The fifth I give you...[UPDATED]

Senegal. 
According to it's Minister of Health, Awa Marie Coll Seck[1,2], a case of Ebola virus disease (EVD) has been imported from Guinea and it is confirmed by testing at the World Health Organization's collaboration Centre, the Pasteur Institute in Dakar.

Interesting that this occurred one week after Senegal closed its borders (again) with Guinea.[3,4] The infected 21-year old Guinean student travelled on 21-August to Dakar. On the 23rd he presented to a hospital but did not admit to being in contact with known EVD cases; Guinea issued an alert that a person with EVD contact has escaped surveillance 27-Aug; Senegal closed its borders around 22-August.[5,6,7,8].
[WHO Disease Outbreak News places his movements ahead of the closure of the border, arriving in Senegal 20-Aug [8]]

These borders are leaky and so the effect of "closure" essentially hinders aid, trade and economy (all very important to the region, especially right now) but very clearly does may not stop the spread of human hosts-as we have seen here. 

Humans are the variable in outbreaks. 

They behave differently each time. 

They respond differently each time. 

This is why no two outbreaks are identical. 

It's why you're a mug to assume this outbreak will be like the last outbreak.

While it looks like this is now a case study in why closing a border is ineffective, I maintain a position that border closures can't contain infectious disease. And please, do not point me to "temperature measurement" as a way to ensure capture of infected individuals. You could easily be harbouring an infection that does not yet express the symptom of fever. 

Click on image to enlarge. 
Graphic lifted from a great CNN video narrated by
Dr Sanjay Gupta. The video describes an example of
contact tracing and its importance to the fight
to contain EVD.[2] 

The contact tracing starts in Senegal now. A 42-day clock starts for the country and a signs and symptoms watch continues on all this case's contacts for 21-days.

References...

1. http://in.reuters.com/article/2014/08/29/us-health-ebola-senegal-idINKBN0GT1CD20140829?feedType=RSS&feedName=health&utm_source=dlvr.it&utm_medium=twitter&dlvrit=309303
2. http://edition.cnn.com/2014/08/29/health/ebola-outbreak-senegal/
3. http://www.washingtonpost.com/news/world/wp/2014/08/29/the-ebola-virus-has-spread-to-senegal-as-the-deadliest-outbreak-in-history-gets-worse/
4. http://www.washingtonpost.com/world/africa/alarm-grows-as-ebola-outbreak-spurs-more-flight-cancellations-border-closures/2014/08/25/87e6d020-2c66-11e4-994d-202962a9150c_story.html
5. http://www.bbc.com/news/world-africa-28893835
6. http://fox59.com/2014/08/22/senegal-closes-its-borders-with-guinea-over-ebola-fears/
7. https://www.internationalsos.com/ebola/index.cfm?content_id=434&language_id=ENG
8. 
   

The battle of Ebola gains a second front...the Democratic Republic of Congo (DRC; formerly Zaire) [UPDATE #3]

So there are three reasons for this post. 

• It may be a little while before we get solid confirmed information from the DRC and I think maps are useful for those of us who are ignorant of where countries live! [See below for update from WHO]
• I'm looking for a quick post so I can move the previous post's grisly pictures down the page!
• Mike Reid (see comments below; many thanks) brought to my attention that the range of the hammer-headed bat (Hypsignathus monstrosus; [5]) overlays the current ebolavirus outbreak areas strikingly well. I lifted that range graphic and (imperfectly, in pink) overlaid it onto my map - et voila!

Data for the hammer head bat's (Hypsignathus monstrosus) range come from The International Union for Conservation of Nature (IUCN) Red List of Threatened Species. I adapted the graphic for VDU from Wikipedia [3]

An 24-Aug report quoted the Minster for Heath, Felix Kabange Numbi.[2] This latest outbreak occurs in a country that was the site of the first (known) outbreak of a virus of species Zaire ebolavirus (called Ebola virus [1] or EBOV), and which has had six other battles with Ebola virus disease (EVD).

One of the two viruses was reported to have been genotyped as a member of the species Sudan ebolavirus (SUDV) and the second was a "mixed" infection of SUDV and an EBOV.[2] A mixed natural infection of a human would be very...unheard of. Can't really say much more though, until we get this all clarified. 

A 26-Aug WHO-AFRO update noted that the index case, a woman from Ikanamongo village, died 11-Aug sometime after butchering a bush animal.[6] 24 suspected cases of haemorrhagic fever occurred between 28-Jul and 18-Aug. 

The latest updates define that the outbreak is solely due to viruses from the species Zaire ebolavirus.[7,8,9] The EBOV viral variants share 99% nucleotide identity with the Kikwit lineage of viruses from this same species (not "strain"). Put simply, this is the evidence needed to be able to state that the two concurrent EVD outbreaks (indicated in the map above as distinct events), are indeed due to genetically distinct viral variants of Zaire ebolavirus and are not related outbreaks. 

For more on naming ebolaviruses - check out my earlier post "Behind the naming of ebolaviruses".[10]

This latest outbreak was previously and relatively quickly (too quickly? Perhaps a message in there for all of us) described by the World Health Organization as being due to gastroenteritis with haemorrhaging...

.@Fla_Medic It is febrile gastroenteritis with haemorrhaging. If i can find the notice, I will posting. DRC is definitely not #Ebola. Best
— Gregory Härtl (@HaertlG) August 21, 2014

SitRep on #DRC and febrile gastroenteritis with haemorrhaging is only available in French. I can send by email if u ask me. It is not #Ebola
— Gregory Härtl (@HaertlG) August 21, 2014

...but subsequently we learn today that...

.@Potrblog @WHO I was given premature information from the field. National lab has now tested + for #Ebola. Will be confirmed in a 2nd lab.
— Gregory Härtl (@HaertlG) August 24, 2014

The outbreaks share at least one common potential animal vector range. This is one of three bat species often pointed to as a possible natural host for ebolaviruses.

Since this is not the first time concurrent outbreaks of ebolaviruses have occurred, I was wondering about seasonal factors and whether they attract or affect bats. This new information adds another piece of of the puzzle.

References

1. http://virologydownunder.blogspot.com.au/2014/08/behind-naming-of-ebola-virusesnot-yet.html
2. http://www.aljazeera.com/news/africa/2014/08/congo-ebola-outbreak-2014824183430461469.html
3. http://en.wikipedia.org/wiki/File:Hammer-headed_Bat_area.png
4. http://www.iucnredlist.org
5. http://en.wikipedia.org/wiki/Hammer-headed_bat
6. http://www.afro.who.int/en/clusters-a-programmes/dpc/epidemic-a-pandemic-alert-and-response/outbreak-news/4263-ebola-virus-disease-drc.html
7. http://reliefweb.int/report/democratic-republic-congo/update-ebola-virus-disease-drc-no-5-30-august-2014
8. http://www.who.int/mediacentre/news/ebola/2-september-2014/en/
9. http://reliefweb.int/report/democratic-republic-congo/virological-analysis-no-link-between-ebola-outbreaks-west-africa
10. http://virologydownunder.blogspot.com.au/2014/08/behind-naming-of-ebola-virusesnot-yet.html

Ebola virus in semen is the real deal.... [UPDATED]

The World Health Organization (WHO) Ebola virus disease factsheet notes that ebolaviruses may be transmitted via the semen of a male who is getting over an ebolavirus infection, for a period of 7-weeks (~49-days).[1] 

The European fact sheet for health professionals and a Public Health Agency of Canada Pathogen Safety Data Sheet both note the 7-week figure, the latter also adds a 61-day figure.[2,3] 

The United States Army Medical Research Institute of Infectious Diseases (USAMRIID) Medical Managements of Biological Casualties Handbook (7th edition) notes a 3-month (~80-days) period, during which one should probably avoid sexual relations so as not to deliver virus directly to a mucosal surface.[4]

Semen is therefore listed as one of the body fluids from which Ebola virus disease may be contracted. 

While convalescent patients seem to be discharged before 7-weeks have elapsed, I presume the men are made very aware of this risk. This was specifically noted in one of the studies below. [8] 

But I find it hard to just accept things. 

As a scientist I'm used to looking for the little bracketed or superscripted numbers or perhaps "(Scientist et al)", at the end of sentences. Then I can check out the information source for myself. So here, I thought I'd try and add those and pt it altogether in one place here - and you can do your own checking out if you feel the need. 

Here are the research papers I've found for EBOV so far (there are also Marburg virus studies) - by all means send me any others I've missed and I'll add them.

• Bausch and colleagues [5] were able to isolate, in cell culture in the laboratory, infectious Ebola virus (EBOV) from the semen of 1 of 2 samples from a single recovering patient who had EVD. 
• The samples was collected 40-days after disease onset; at 45-days he was no longer positive for EBOV
• No acute phase (active infections) samples were tested.
• 1 of 2 samples were also positive for EBOV RNA by RT-PCR (detecting a portion of the virus's RNA genome)
• Rodriguez and colleagues [6] could isolate infectious EBOV from seminal fluid 82 days after disease onset from a 27-year old male (also RT-PCR positive then). A sample at 51-days after onset was RT-PCR positive, but did not yield infectious virus.
• EBOV RNA , but not virus, in 3 other convalescent cases (33, 29 and 25-years of age) at times ranging from 57 to 101-days after disease onset.
• Rowe and colleagues [7], who examined the same patients, detected EBOV RNA by RT-PCR from 4 convalescent cases (27, 25, 29 and 33-years of age as above) at times ranging from 47 to 91-days after disease onset 
• No infectious virus could be isolated and no viral antigens were found
• Emond and colleagues [8] were able to isolate infectious EBOV from seminal fluid collected 39 and 61 days after disease onset
• No EBOV was isolated 76, 92 or 110-days later

So if you are a man who has been diagnosed with an Ebola virus infection and survived, please, seriously, take extra care to practice safe sex. Use a condom. Or, even safer, just wait.

References...

1. http://www.who.int/mediacentre/factsheets/fs103/en/
2. http://ecdc.europa.eu/en/healthtopics/ebola_marburg_fevers/factsheet-for-health-professionals/Pages/factsheet_health_professionals.aspx
3. http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/ebola-eng.php
4. http://www.usamriid.army.mil/education/bluebookpdf/USAMRIID%20BlueBook%207th%20Edition%20-%20Sep%202011.pdf
5. http://jid.oxfordjournals.org/content/196/Supplement_2/S142.full
6. http://jid.oxfordjournals.org/content/179/Supplement_1/S170.long
7. http://www.ncbi.nlm.nih.gov/pubmed/9988162
8. http://www.ncbi.nlm.nih.gov/pubmed/890413

Protect the healthcare workers>>save lives>>stop Ebola virus disease

I live in Australia.

I have clean water on tap. Reliable electricity to burn. Internet access. A green garden. A lawn. A car. A very old cat who gets medical attention when he hiccups. A washing machine. A clothes drier. My kids have computer access. I have at least a dozen doctors within a 5min drive. 

I'm a virologist who has been through all levels of schooling available, then University, then went on to do a PhD. I'm privileged. I'm lucky. 

I want to help West Africa get its Ebola virus outbreak under control. I want to help support the healthcare workers (HCWs) that are far braver than I am. I want hem to live to fight another day in the mud, heat, fear and pressure. And to leave when the job is done and return to their lives as the heroes they are.

I don't know much of what is being done to help though. 

I don't know whether my own government is providing supplies in my name. I'd like them to be. I'd like philanthropists and industry and people who take my money to stop, and give some of it to help out. I'd particularly like those funds to be used right now to purchase, deliver, distribute and secure a steady stream of personal protective equipment (PPE) to all those well-trained HCW individuals and organizations battling to contain an acute, untreatable, easily spread, often fatal viral disease in countries with some of the poorest healthcare...In. The. World. I want them to have gloves, gowns, masks and goggles. I don't want them to have to re-use PPE and be infected in the process. I don't want them to be in fear of stopping a terrified potential patient from running away because they don't have the PPE to feel safe in just holding that person's arm and saying, "stay, we are here to help, if you leave we can't do that and you are more likely to die".

I don't feel guilty that I want this done for this disease now and not that disease all the other times.

But what can I do?

I donate some of my money. I do this every year anyway but I'm donating some more now because there are some worthwhile organizations that I trust to help West Africa, now. I don't send myself into debt. But I give a chunk now. I gave a chunk last week. I'll give another chunk soon. Some of this will be in my name, some in my wife's and some in my kid's name. Some might be a present for someone else. If we all did that, we could help. But we shouldn't just give it to organizations or individuals who have no plan or skills to use it. Or to those who will spend it on salaries and overheads.

So I give my donations to these organizations now:

• Médecins Sans Frontières (MSF)
  They are meticulous, fastidious and well trained so they don't needlessly risk themselves. They are on the front lines everywhere. They have been all over this outbreak from early one. They warned us.
  http://www.msf.org/
• Direct Relief
  They can (and have) mobilize the PPE I want delivered. They have contacts with others in industry. They are a nexus for getting this done.
  http://www.directrelief.org/
• International Federation of Red Cross and Red Crescent Societies.They are one the ground helping keep locals informed about Ebola virus
  http://www.ifrc.org/
• United Nations International Children's Emergency Fund (UNICEF)
  Always finding way to help children. There is a growing orphaned population in West Africa.
  http://www.supportunicef.org
• United Nations Foundation Ebola Response Fund
  The UN created this fund as way to allow individuals, corporations and civil society organizations to directly support UN entities in their efforts to respond to the Ebola virus disease outbreak.
  https://secure.globalproblems-globalsolutions.org/site/Donation2?8780.donation=form1&df_id=8780

Some organizations I have not donated to yet, but like the look of...

• Africare
  Among other things, they are helping to outfit health care workers with PPE in West Africa
  http://www.africare.org/
• globalgiving
  Among other things, they are helping educate and provide medical supplies to the countries under Ebola virus assault
  http://www.globalgiving.org/
• actionaid
  Spreading awareness about Ebola through village visits, music, explanation, drama...and some pretty cool dancing!
  http://www.actionaid.org/videos/ebola-door-door
• EMERGENCY PROJECT: Medical supplies for Liberia via FundAnything
  Joseph Flores is trying to fill a pre-organized shipping container with PPE
  http://fundanything.com/en/campaigns/emergency-project-need-more-medical-supplies
• USAID
  Has a link to a range of agencies seeking funds to help stop the Ebola virus disease outbreaks
  http://www.usaid.gov/ebola
• Australia Red Cross: Ebola Outbreak 2014 Appeal
  Providing education, care and aid with burial
  http://www.redcross.org.au/ebola-outbreak-2014-appeal.aspx

Some other recipients for your chunks could be in these lists...

• From Caitlin River's blog
  http://www.caitlinrivers.com/blog/how-to-help-fight-the-ebola-outbreak
• From Kelly Hills' blog (h/t for heads up on Direct Relief)
  http://www.kellyhills.com/blog/aid-organizations-working-in-ebola-regions/
• ONE's blog list of humanitarian organizations
  http://www.one.org/international/blog/ebola-support-the-humanitarian-response/

I am also making others aware of these organizations so they can add their chunks in - if and as they see fit. You can do that too. 

If you have a favourite company, try contacting them. If you have a favourite movie, hit up the actors, producers, directors. THe UN have a Try anything. Spend an hour tomorrow looking up some people and sending them an email or a Tweet to ask them to help provide the fuel needed by the people who know how to get this done.

Be part of helping out. 

Ebola West Africa numbers in context...[AMENDED]

A quick glance at how the suspect, probable and laboratory confirmed (susp/prob/conf) cases of Ebola virus disease (EVD) stack up in the 3 countries with local spread of Zaire ebolavirus.

Please note that I have separated Guinea-2014, Sierra Leone-2014 and Liberia 2014 only to highlight that each country in the single "West Africa" outbreak (involving a single viral variant as far as we know) has greater case numbers than those found in many of the earlier outbreaks.

I have not yet listed the case imported to Nigeria here.

Click on chart to enlarge.

Ebola Virus Disease (EVD) 2014 West African outbreak..

A new static page on which I will update the 2014 West African Ebola virus disease (EVD) outbreak numbers after they are released by the World Health Organisation (WHO).

The WHO have commenced creating multi-page Situation Reports.[2] They contain more granular data than is publicly available. They will be reported at least once per week.

If I become impatient, I'll cobble together the individual country's numbers via reliefweb.int, then update that once WHO data are available (which may result in a drop in totals as WHO numbers may have been collected a littler earlier).

Latest data taken from: http://apps.who.int/iris/bitstream/10665/135029/1/roadmapupdate26sept14_eng.pdf?ua=1
Date of DON: 26-Sept
Dates covered: 23-Sept

Learn About Tableau

Learn About Tableau

A note about the proportion of fatal cases (PFC): 
On these graphs, my PFC calculations for West African countries and the DRC are based on dividing the total number of suspect/probable/confirmed deaths by the number of total suspect/probable/confirmed cases for the same date. This is crude and may be a sizable underestimate of the true PFC.

It may be better to use the deaths at the most recent date divided by the total cases from 9-14-days  earlier (this number is not precisely known) to better account for the lag in time between presenting to a treatment facility and dying (for those who do not recover). 

Some estimates suggest the true PFC may be closer to 80%. I don't have enough data (or smarts) to be able to calculate that for now so please be aware the PFC above is likely an underestimate.

Reminders:

• The chart above, as with all on VDU, is made for general interest only. It is also freely available for anyone's use, just cite the page and me please. It may be that I have misinterpreted the language in the reports (sometimes a little tricky to wade through) or miscalculated some totals based on the way data have been presented. 
• Sometimes there are very country-specific differences in what gets presented to/via the World WHO DONs/SitReps which make this process less clear than it could be. I recommend you have a read and compare the data from each of the countries for yourself to understand these issues. 
• As I've talked about previously,[1] these numbers are all volatile for a variety of reasons, some Ebola-specific, so regard this chart for its trends only.
• I am only able to plot what is publicly available. To date, this does not include granular data with dates of onset, or daily data of any kind. The WHO have these data and you will see them become more available through their Situation Reports found here http://www.who.int/csr/disease/ebola/situation-reports/en/

References...

1. Ebola virus disease and lab testing...http://virologydownunder.blogspot.com.au/2014/04/ebola-virus-disease-and-lab-testing.html
2. Ebolavirus outbreak Situation Reports
    http://www.who.int/csr/disease/ebola/situation-reports/en/

West African Ebola virus disease (EVD) outbreak flares up in late May and in early June...[UPDATED]

Data are based on WHO DONs. Lines use the numbers on the vertical  axis on the left, bars use the right hand axis. The percentages are the proportion of fatal cases at the time point indicated.
Click on chart to enlarge.

The chart tells a pretty grim story of an outbreak that has flared up, after what looked like some weeks of things settling down. I'd said I would stop charting this outbreak back at 5-May, unless anything major happened. Well it did. In late May in Guinea and then in early June in Sierra Leone.

The causes seem to be the heartbreaking stories of family members sequestering ill loved ones or removing them from isolation wards, and in so doing, getting infected themselves, and so spreading infection.

Click on image to enlarge.

Maps purchased from maptorian and adapted by VDU

The adjacent map has been updated to help communicate an idea of the number of cases in each country.

The number of cases and deaths, not all of which are laboratory confirmed as being ebolavirus disease (EVD), are now the highest of any known outbreak of EVD (see the chart below). A grisly fact and one that doesn't change anything. But one I note nonetheless. Also worthy of note is that throughout this outbreak, the proportion of fatal cases (PFC; check the disclaimer in the legend below) has not reached the heights of the Zaire outbreak of 1976, or the Democratic Republic of Congo (DRC) outbreak of 1995, or that in the Republic of Congo (RC) during 2002-3, and others. So that's a small silver lining.

A guide to confirmed EVD cases and those who died from EVD over time.
The data for the non-West Africa-2014 outbreaks, sourced from Public Health England website [1], are defined as "confirmed". Not all of the Wet Africa-2014-related clinical cases or deaths have been laboratory confirmed so these bars are probably a little high (highlighted in the key). Note that looking at proportions alone can be confusing. For example, if 1 of 1 cases is fatal, that's a PFC of 100% but it may not reflect the situation accurately. So please interpret the grey mountains alongside the read and blue bars to get the complete picture. DRC-Democratic Republic of Congo; RC-Republic of Congo

Click on chart to enlarge.

I'll try and keep the charts up-to-date as this outbreak continues to burn. 

References...

1. http://www.who.int/csr/don/2014_06_18_ebola/en/
2. http://www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/Ebola/GeneralInformation/

Ebola virus disease (EVD) West Africa update for 02-May, WHO-AFRO update...

Click on image to enlarge.

Thankfully the latest World Health Organisation update includes figures for Liberia. The last West Africa update did not, so I didn't post a chart.

Summary..

Total suspected/probable/confirmed cases: 244
Total suspected/probable/confirmed deaths: 162 (66.4%)
Total lab confirmations: 133 (54.5% of 227)

These figures are very important for two reasons...

Firstly they show a drop in suspect/probable cases after data scrubbing by the Liberian Ministry of Health and Social Welfare. This reinforces that the outbreak is being well controlled.;The date of isolation of the most recent confirmed cases is 30-April from Conakry and Guekedou (Guinea).

Secondly there has been a concomitant rise in the proportion of fatal cases of EVD due toZaire ebolavirus (see the percentages above the orange line in the chart). This is not because the numbers have jumped, it's because the denominator has shrunk for the relevant calculation:

No. EVD fatalities/No. total susp/prob/conf cases.

We've known this rise in proportion was coming because it was highly likely that case numbers would change as the dust settles and the susp/prob EVD patient numbers get discarded because they are found to be infected by something else; clinically similar disease, but not because of infection with Zaire ebolavirus. I've written about it previously if you'd like some background.

With the use of more antibody testing, the numbers will continue to change, as they always do in outbreaks.

This will be my last update on this outbreak linked to the WHO-AFRO announcements unless anything major happens.

A reminder - the chart above is made for general interest. It may be that I have misinterpreted the language in the report (sometimes a little tricky to wade through these reports) but the trends should still be informative even if a number or data point is out of place.


Sources...

1. http://www.who.int/csr/don/don_updates/en/
2. http://reliefweb.int/report/liberia/unicef-liberia-ebola-virus-disease-sitrep-20-2-may-2014
3. http://virologydownunder.blogspot.com.au/2014/04/ebola-virus-disease-and-lab-testing.html

Update on Ebola virus disease (EVD) case accumulation chart with new WHO African Regional Office SitRep data for 17-Apr-2014.

A new World Health Organisation (WHO) Situation Report on the Ebola Zaire outbreak in Western Africa has filled in all my whinges from last night (see them here).

I've updated my chart and finally worked out how to show negative case number adjustments - just to show that numbers have not always been going upwards, highlighting that the numbers will change as suspected and probable cases are discarded if laboratory testing does not support the suspicions.

As a reminder - this charts are made for general interest. It may be that I have misinterpreted the language (sometimes a little tricky to wade through these reports) but the trends should still be informative even if  number is out of place. If that is the case, feel free to pick me up on it - it will hopefully be corrected during my next update anyway.

Update on Ebola virus disease (EVD) case accumulation chart with new WHO African Regional Office data for 11-Apr-2014.[AMENDED]

Lines use the axis on the left, bars use the right hand axis.
Click on image to enlarge.

Its been 4-days since the last World Heath Organisation update on the changing situation with Ebola virus disease (EVD) in Western Africa (10-April, covering numbers from 9/10-April). Yet the update we received over night (my time) only advances the case numbers by 1-2-days, covering numbers from 11-April.

Total suspected/probable/confirmed cases: 193
Total suspected/probable/confirmed deaths: 119 (61.7%)
Total lab confirmations: 77 (39.9% of 187)

There are a constant stream of social media comments about case numbers blowing out in one place/region/country or another, hashtags like #terror and #WMD, statements about unwillingness to shake hands not meaning to be an insult (but slightly more emphatic than that at times), plumpynut or onion magical remedies (they are not remedies so please ignore the magical cures (they come from ignorance and are not backed by science), implications that cases always bleed (41% in one past outbreak) and then there's the border closures and flight restrictions...

I think that the more regularly the world receives simple and reliable information on any outbreak that scares them - from the locals and volunteers who have to stare the virus down to the causal observer with the attention span of a fruit fly - the more able they are to filter out the noise and learn from the facts. I think we've all learned something about EVD form this outbreaks as we will any outbreak if we look harder enough and are willing to be educated. Its a grisly, scary but ultimately much more manageable type of virus outbreak than each year's epidemic of seasonal influenza is. Be alert but not alarmed hmm?

This announcement from WHO social media communications front man Gregory Härtl was a very welcome one in the context of that windy paragraph...

.@girlofcelje @MackayIM An update is planned for today. From now,they will b Mon,Weds,Fri. Don't follow advice that could endanger your life
— Gregory Härtl (@HaertlG) April 14, 2014

The latest graph, above, is based on these new WHO-AFRO data. It shows that cases continue to accrue slowly as do deaths and lab confirmations. Case numbers have risen by 7 since the previous report and the proportion of fatal cases, which includes suspected, probable and confirmed EVD cases, is now at 61.7%. While that proportion is a horrible number, the rise in case numbers is not exponential. Mali's samples are still being tested and so no change in suspect case numbers there. Among Guinea's 106 deaths, 42 (39.6%) have been laboratory confirmed. There is also a mention of a possible funeral-related cluster. No word on how many transmission chains are being watched now. I may have misread this, but not long ago I thought that all cases could be linked to just one source. This cluster may suggests that may have changed and a statement on this aspect of the EVD outbreak in West Africa would be helpful.

The most recent suspected EVD case onset noted in the report arose 10-April-14.

We eagerly await the next update.

Sources...

1. Ebola virus disease, West Africa – update [10-April with data from 9/10-April]
   http://www.who.int/csr/don/2014_04_10_ebola/en/
2. Ebola virus disease, West Africa (Situation as of 14 April 2014) [Data from 11-April]
   http://www.afro.who.int/en/clusters-a-programmes/dpc/epidemic-a-pandemic-alert-and-response/outbreak-news/4095-ebola-virus-disease-west-africa-14-april-2014.html