Les Roberts – “Day 53: What R0 is not.”

Les Roberts – Freetown, Sierra Leone – November 26th, 2014

Day 53: What R0 is not

If you believe all those old CDC guys, the first cohort of HIV cases in San Francisco in the 1980’s supposedly had sexual encounters with, on average, over 1000 people in the year before becoming ill. Certainly something close to HIV had been circulating around in the Congo basin for decades, if not centuries. CDC has a blood sample in their freezer from an adult male from Kinshasa taken in the 1950’s that contains HIV. Genetic evolutionists put the origin far far before that. And that should not be surprising. Imagine some hunter butchers a chimp and cuts his hand, he gets something close to HIV… maybe it makes him sick, maybe his wife dies too, who would ever know that one or two people died of some slow funky illness in that Congolese village? It was not until HIV got into a hyper-sexually active cohort that enough “infectious momentum” could be in place to get the disease into blood supplies, commercial sex workers, and all those footholds that HIV gained on the road to becoming a major global burden. I am quite sure: what San Francisco bath houses were to HIV, West African funerals have been to Ebola.

There are widespread traditions in Sierra Leone that suggest the body of your loved one needs to be washed to cleanse the spirit so they will be accepted by the ancestors. Allowing them to be buried unwashed would be for many something akin to Christians damning someone to hell. Funeral attendees often kiss the corpse as well… like in the US. Thus, people, usually women, commonly cleanse and wash the body after death. They will then often pour the rinse water over themselves to bask in, and respect, the decedent’s spirit. And, as if that wasn’t microbiologically disastrous enough, then these women usually prepare food for the large number of people coming to the funeral. This is a virus whose concentration in the body spikes with the acute phase of illness and where death often releases millions of viruses that ooze out afterwards. It would be hard to dream up a more perfect way to spread this virus around than the traditional West African wash & rinse funeral. For the first months of this outbreak, almost all big transmission chains were associated with funerals and in the CDC’s VHF dataset, the majority of cases through September reported recently attending a funeral. That fraction has dropped dramatically! Maybe less than 10% now. It may be that the outbreak has enough “momentum” to keep running wild without funeral transmission, but no one knows.

When I got here two months ago, of the major elements needed to achieve the two major UN goals (70% of bodies buried safely and 70% of cases isolating themselves early in the course of illness by seeking treatment), almost nothing was functioning well. Now, major progress has been made on the safe burial front. There are lots of articles written about the burial system falling apart (e.g. http://www.bbc.com/news/world-africa-30191938 ) but those are the exception. The safe burial effort is perhaps the major success. The bad centralized data suggest about half of all deaths are buried by safe burial teams (which is on paper required by law for all deaths) but I suspect the fraction of Ebola deaths buried safely is significantly higher. In our surveillance sensitivity exercises, out in the smallest villages far from the paved roads, most chiefs are adamant about calling burial teams if they think they have an Ebola death. Does the family wash the body before the teams come? Yes, probably. But, it may not be such a huge deal if there are no funerals, no meals, and no kissing the corpse components to the burial. It is stunning how in our field work often eight, ten, or all of a household can get infected with no neighbors getting the disease. Funerals somehow seem to be an incredibly powerful mechanism to move this reluctant but pernicious disease between houses and villages.

Recently, in the most out of the way village I have visited, there were four families out in the fields in the mile before the village and we saw those people as we approached but they always hid as we got close. I am not sure if they fled from Ebola laden villages or were driven out because a family member got sick. Then when our car rolled into this village of around 200 people, everyone slipped inside and there was suddenly no one to be seen. It was only because the driver was from that Chiefdom and spoke with the perfect dialect that people could be lured out. They were scared… scared of anyone from outside and the risk they might bring Ebola. Things are not as they were in July!

By and large, people don’t go to funerals now. Certain people don’t tolerate commercial sex with outsiders. There is a lot changing and I am convinced that in the few weeks to come the outbreak will peak… not because of what the health community has done, but because people have changed their behaviors and thus changed that interaction between virus and culture that determines the R0. With flu, R0 is largely determined by the intrinsic nature of the virus and people talk about it, and model it, as if it is an internal characteristic. With suicide, no one would consider the degree to which is contaminable or transmissible some fixed internal characteristic, because, to the extent suicides come in clusters, it is viewed as a social and psychological contagion. In this regard (the degree to which the R0 is intrinsically or socially determined) , I am convinced that Ebola is far closer to suicide than flu. I am frustrated by our (my!) inability to get NGO’s to step-up and operate treatment centers and the ability to make treatment beds available. (But, our former Emergency Medicine Fellow, Trina Helderman has just come this week bringing the NGO Medair…sort of a Swiss based mini-MSF, so hope lingers.) But, I expect history to show that the outbreak turned around because the people of Sierra Leone changed the communicability of the disease. When that happens, I hope the American public will be able to be convinced that Ebola would almost certainly have an R<1 in the US and spend their fear and energy on more dangerous socially induced diseases, like fat intake, or lack of exercise, or Governors who want to be President.

Onward!

Les

Advertisements

Les Roberts – “Day 51: Protecting the public from epidemiological data”

Les Roberts – Freetown, Sierra Leone – November 24th, 2014

Day 51: Protecting the public from epidemiological data

It is rather astonishing here how much of the data I and others collect cannot be shared. It is not that the data is about things people don’t know. It is not that the data is about secret findings… it is about keeping the press and academics from saying stupid things and attributing it to WHO.

We have done a series of sensitivity analyses of the major CDC created surveillance system, the VHF, that everyone knows is incomplete. It is consistently 10 or 20% lower than the weekly district reports probably because somehow 10 or 20% of cases fail to be properly documented and transferred on through the steps of the surveillance process (e.g. the case report does not get filled out, or gets lost, or gets missed at the data entry office on the district level….or because half the freakin’ country have one of about six first and last names so they see 17 people named Mohammed Kumara from that district and think that their Mohammed Kumara has already been entered…). But, say out loud with data what everyone knows, for example that most of the cases are not being detected, and wow do the cheap seats in Atlanta and New York start rattling.

The most stunning censorship is the reluctance of anyone to show the epidemic curve. This is because the data takes time to get into the system (both the CDC VHF system and the MoHS “call to the Districts every day” system). It takes days for suspect cases to be tested and confirmed or sent home. It takes days for the data to get entered into the database. There are all kinds of delays… that when presented as an Epi curve, constantly give the impression that the outbreak has peaked and is coming down over the last two weeks.

les

Above is a classic example from this past Friday’s local Sit-rep. It is mostly based on the MoHS data so the dip is not as dramatic as the VHF database. Most every reporter and fancy-pants modeler that has never done contact tracing or data entry form hospital forms will be tempted to report that the outbreak appears to be going down. This is actually what going up looks like. It would be fine if poorly informed people misinterpreted and then moved on to the crossword puzzle, but more often, the press officer and we in the office need to squander time explaining about data flow and delays. And then there are aberrant events.

If one looks at the week of September 21 above, it looks like there was a spike in suspected cases and then a dip. In fact, there was an outbreak of coding errors combined with the largest lab near Port Loko (the district with the highest incidence) shutting down for the week. Thus, those suspected cases from the week of September 21 mostly died without ever being laboratory confirmed and thus they will stay suspect forever. Since back in September, it took 4 or 5 days to get a lab test back (it is much shorter now), and then the data record had to be updated, typically cases that appeared as suspect in the week of Sept. 21 would mostly change to confirmed in the week of Sept. 28, but that never happened that week resulting in an artifact of apparently elevated numbers of suspect cases one week and fewer cases the next. There are issues like this or bigger in every data source I see every day… so people just do not share data and findings… not with the press, not with your peers who might share it with the press, and heaven knows not with Geneva!

Ah, the things they don’t teach you in intro Epi!

Les

Les Roberts – “Day 49: Each in their own way”

Les Roberts – Freetown, Sierra Leone – November 22nd, 2014

Day 49: Each in their own way

I went to a house a couple weeks ago. We were trying to see if household quarantine caused or prevented secondary cases in the home. We went to a house that was not quarantined and where over a four week period, 14 out of 16 household members had developed ebola and 12 had died. Only about four ever went to a clinic because there were no beds free.

There was a neighbor….he reminded me of my late father-in-law. He was just a regular guy. If he was in the US, he would own a hardware store or be a little league baseball coach. At the outbreak peak of the neighboring house that we went to see, the 13 year old girl in the house started to show symptoms. This neighbor went and took the girl to his house and put her in the cooking hut and made her drink. When another sister got sick, he brought her over too. When the second sister started vomiting blood, he cleaned out a bedroom and moved the 13 year old into his house… and she lived. Now, the family is disbanded and the 13 year old lives with this neighbor. She got teary eyed as we discussed her family… but those two now have a lovely bond that is clear for all to see. I am sure that the neighbor didn’t really know exactly what he was doing, but he just desperately needed to help, and help he did. That is a really nice aspect of this crisis. As with all crises, little people are doing their part for the big picture, even if it is trying to help by the most indirect of means like teaching children at night in this chapter of closed schools or cooking for others.

©Roberts, 2014

John doing his thing.

Every day, seven days per week, John makes me breakfast. He stands out in the meal area at my hotel cooking eggs and making sure the spread is proper. He is the master chef of the hotel and very witty and good natured. Every morning, we have a little shtick that we go through where I ask him what will we be having for breakfast and every day the answer is something else: a Lapland omelet, a hopeful omelet, an Australian omelet (from way south, with a pouch, that has a little baby omelet inside). It is always the same omelet, just with a different name and explanation. He speaks Japanese with my Japanese colleague, he speaks French well, he speaks Spanish. It turns out that he is a Sierra Leone born, high end chef from London. When Ebola arrived here, he just had to come home to help. His 15 year old daughter thinks it is fine he is here. His 23 year old daughter was visiting for the summer when the war broke all those years ago and was pretty traumatized; she is not at all understanding about John being here. He cooks here at a hotel filled almost exclusively with WHO employees and members of a Scandinavian logistical group call IHP (who are unfalteringly reliable and competent in a way WHO and most everyone else is not). Being a chef is not very logically related to stopping ebola… but John wants to help and what he knows how to do is cook, so he is cooking. And my life is richer for it in many ways.

This outbreak is really ugly and is out of control. But, there are a lot of nice faces of human nature in Sierra Leone these days.

Cheers,

Les

Les Roberts – “Day 40: KB”

Les Roberts – Freetown, Sierra Leone – November 13th, 2014

Day 40: KB

I work with a guy named Kyobe Bosa. Everyone calls him KB. One of my colleagues was at a public event, a Community care Center (CCC) opening last week, and an official walked up to KB and said, “Good morning Chief.” He was standing next to a Paramount Chief, a Chief of perhaps 100 villages who is elected for life. The Paramount Chief wryly looked over at KB and said, “Not yet he’s not!”

KB has worked for years on infectious disease control issues at the WHO headquarters in Geneva. I suspect, WHO will be his career path for a long time to come. He is from Port Loko District where he is now the WHO field coordinator. When the outbreak happened, he just told his boss, and the Ebola Response crowd in Geneva that he needed to go home.   It is a beautiful thing, how he just has to be home at this moment of extreme need. But what is even more beautiful, is how unabashedly angry he is at the international response. He is perhaps the angriest person I have met here. He laughs a lot. He smiles a lot. But, don’t get him started on the issue of quarantined households not getting food, or how long it takes to have dead bodies picked up, or the contact tracers. Anger, it can be a really constructive thing. People in the relief world talk a lot about local empowerment as if it is a gift from the donors. It is really inspiring to see a local-lad take power!

Les

KB in Port Loko ©Les Roberts

KB in Port Loko: the revolution will not be televised!

Les Roberts – “Day 39: The plural of anecdote is not data”

Les Roberts – Freetown, Sierra Leone – November 12th, 2014

Day 39: The plural of anecdote is not data

This past week, I was assessing the completeness of the main case listing database (a sensitivity analysis) which involved going to villages and asking if there had been any suspected cases in the village during the month of October. In one village, there had been a woman and her two small children who had returned from Freetown just after the three day lockdown (September 28-30). She was originally from the town, was married to a man from the town, but had been living in Freetown for a while. When she returned, the village quarantined her in a store. It is against the law to allow a visitor to stay in your house in Bombali District. But she was from the village so they could not turn her away. Quarantine in a non-house building seemed like the right thing to do in this village that had reportedly never had an Ebola case and was officially closed to outsiders. I am sure they saw this as a humane compromise.

On day 18 of the quarantine, one of the 18 month-old children died in the morning and the other twin died in the evening.  The village chief reported to us that they were Ebola cases. The bodies were swabbed before burial and one is listed as a positive swab in the official CDC VHF database (I am sure you are asking why one and not two….that is the sensitivity part, and I wonder the same thing). The mother supposedly was never sick? Was she an asymptomatic case? Hard to say. The kids could have been infected 19 days earlier (unlikely, but a theoretical possibility). The mother could have really been a case, was discharged and did not tell anyone and somehow infected the kids. Again, unlikely as the very limited fluid sampling I have heard about suggests the virus disappears from breast milk quickly, making it safe, while other fluids like sperm remain deadly for months (Therese McGinn has been saying variations of that same theme for years!). Whatever happened, it was a pretty odd case. As we drove back, a colleague told me one of the guards at a holding center in Makeni had developed fever, been tested, was positive, but never developed serious illness. The next day, another colleague told me of a family where a mother was ill, there were no open beds at treatment centers or holding centers so she was quarantined in the house with her two small children and her sister. The woman died; a week later a kid died, and then the other while the sister spent perhaps 30 days in a house caring for three people as they died, a house that was never disinfected, and she never fell ill. I have now heard perhaps a dozen stories like this.  No one story is very convincing that it was an asymptomatic or mild infection. Taken together, the likelihood that this is not a disease like measles (where virtually everyone can get it) seems to be growing in lots of people’s minds. There are supposedly almost no villages where the attack rate has been more than 20 or 30%. These are often really humble villages where no children have shoes and feces flow like social media in New York. Lots of us are lamenting that there is so much work to do, that there is no time to learn the lessons that are passing before us (like drawing blood in these high attack villages to see if people who report never being sick have antibodies). Maybe next year, when the outbreak has passed…

Instead, tomorrow I am off with my Ministry Of Health mates to measure if quarantine causes or prevents infections within a home. We are planning to interview most of 100 homes… Finally, there will be something more than anecdotes linking quarantine and secondary household deaths. Either way (and I have no idea what we will find) a lot of people are going to be annoyed with the results. Ebola, the rift that keeps on rifting!

Les

Les Roberts – “Day 31: Putting the mean in quarantine”

Les Roberts – Freetown, Sierra Leone – November 4th, 2014

Day 31: Putting the mean in quarantine

I had breakfast yesterday with a former student from many years ago at Hopkins. He and his wife tried to get pregnant and gave up… and then somehow, years and years later, they had a child when his wife was 48. I think only those of us that wanted kids and did not have them arrive can fully appreciate what a magical thing that would be. He volunteered to come here and work in a UN support role and made an automatic reply e-mail stating he was in Sierra Leone. He did not think much about it when his child’s preschool sent him an announcement inviting him to parents’ night. But, the next day, when his wife dropped off their 3 year-old, she was told that the school director needed to speak to her. The director informed her that their son would have to stay home for 3 weeks after the father returned. He is contemplating spending 3 weeks in Europe, away from his family, away from his job, before going home. I have heard so many stories like that!

Everyone appreciates the effect on clinicians of a 3 week work ban, a ban that has some semblance of logic, given the history of ebola affecting health care workers and the intimate physical nature of some clinician activities. But I think few people consider the other indirect consequences of such measures. A co-worker the evening before said how her main reluctance about coming to Sierra Leone was that her mother was very old and not well, and she feared that her mother might die while she was here. Now, given this hysteria in the US, her Thanksgiving-hosting sister has forbid my colleague from coming to her house for Thanksgiving, even though my colleague scheduled this deployment to end mid-November explicitly, so she could have Thanksgiving with her mom. Think of the rift this might potentially make between those sisters.

The Europeans are very entertained by the American hysteria. The idea that 60% of New-Yorkers support the Governor’s crusade against science and ignore MSF’s perfect record of health care worker self-monitoring speaks poorly of the medical community’s capacity to… empathize? … educate? … believe science?

People in Sierra Leone really like Americans. I just hope they never learn how little Americans care about Sierra Leoneans.

Les

Les Roberts – “Day 26: Paranoia may destroy ya!”

Les Roberts – Freetown, Sierra Leone – October 30th, 2014

Day 26: Paranoia may destroy ya!

Yesterday, as I rolled into the hotel parking lot, the guard at the gate took my temperature for perhaps the eight time that day. It was 37.6C… more than two thirds of the way from normal to the dreaded “enter quarantine and get tested” level of 38.0C. The sun was shining on my face so I logically knew I wasn’t sick. I felt fine. But, somehow I simply had to zip straight to my room and open my suitcase, get the digital thermometer, and stick it in my mouth to wait for the beep. 34.9C. I was so sure that I was fine but somehow I would have not been able to think of anything else until I had this external validation of how I felt.

All of my Sierra Leonean counterparts, the expatriates, the drivers, are hyper-aware of their health. To get a case of hiccups raises people’s diastolic blood-pressure by 30 points!

So about 10 days ago it was a little startling when a doctor colleague said, “What happened to your eye?” I went to my room and looked, and sure enough, there was a considerable subconjunctival hemorrhage (this picture was a couple days later when it had subsided). I have never heard of anyone who had hemorrhagic symptoms before fever with ebola but you just can’t help but have your mind wander where it is not supposed to go. I don’t ever remember this happening before without trauma, and other than a tiny fly going in the other eye the day before, I can’t imagine what happened. In the days that followed, I had three doctors look at it and all three were certain of their respective diagnoses: conjunctivitis, blunt trauma, and hypertension . The bloodshot eye is mostly better. The paranoia is unfaltering.

Les

Driver gets scanned too

Driver getting scanned upon arrival at office

bloodshot eye

What is that?

Les Roberts – “Day 23: The building next door is on fire!”

Les Roberts – Freetown, Sierra Leone – October 27th, 2014

Day 23: The building next door is on fire! But fire is dangerous, so anyone who enters will have to be quarantined in there for 21 days after the fire ends.

There is grim news to report from the vantage of Freetown. There is a deadly outbreak threatening worldwide safety: an outbreak of unadulterated insanity in the US. In our beloved State, the Governor, and his neighboring New Jersey Governor, has decided to enforce a three-week quarantine on any health workers returning from West Africa.

MSF has now had over 500 expatriates come to West Africa and return home. They have had several staff become infected, several of whom were evacuated to Europe, and I believe, none of whom are known to have infected anyone else. They have had an unknown number develop mild or asymptomatic cases. They have had at least one develop disease after going home. Their strategy for protecting the lands to which they repatriate is to have their staff monitor their temperatures twice daily and report-in to the MSF monitoring network daily for three weeks. The logic is that people can go about their daily lives with virtually no threat to those around them up to the point where an Ebola infection produces fever. Thus far, their record has been… perfect. That is, an R of zero! Of course, there will be cases in the future and this system will not be perfect if this outbreak keeps up. Of course, having CDC and health departments chase down hundreds of contacts is expensive and resource consuming. But since the outbreak began, thousands of people have returned to the US from this region and almost none has triggered contact following and significant public expenditure.

Stop and ponder, if Europe, or for that matter, the entire world followed the New York example. Almost certainly, this outbreak would blossom and spread and extend to Europe and wash across the US borders within the coming years. Global quarantine of the three affected nations would almost guarantee Ebola remaining prevalent here for a long, long time. Like measles or shigella or any of those other more transmittable and opportunistic diseases that blossom among the world’s poorest, travelers would be bringing the infection to our shores continuously as they do with measles and shigella. While less transmittable, Ebola has a noteworthy difference from measles – it is significantly more deadly. The best “high probability” approach we have to not being on hyper-alert for Ebola in the US for many years to come is to stomp this out now In West Africa. The US is doing its part here, as are the British and the Chinese and many other nations. But these nations would never find enough people and the right people to deal with this crisis if they established New York and New Jersey type quarantine rules.

I was just today in Romeni, a town under quarantine with military posted at each end of this one-road town of a few thousand in an attempt to keep infectious cases in the town. No one except health workers can go in and out. It was a little bizarre to see large numbers of adults hanging out in the middle of the day. Most chiefdoms now have a rule against allowing a stranger to sleep at your home: there is a $100 penalty for this act. These protected towns usually have young men guarding the edges against strangers coming into the town. While WHO does not endorse all of these quarantine approaches, in this setting, with this culture, I am not sure if these quarantine controls are a bad idea; there is no track record for evaluating this. (I am quite sure all of the quarantined towns that are not getting any food are a bad idea, but that is another discussion.) In contrast, we have a pretty good body of evidence that before infected individuals are febrile, they do not shed the virus and pose almost no risk to others. Keeping such people out of your state or off your subway probably produces no measurable benefit but creates a great barrier to allowing New York and New Jersey residents from being part of the solution.

There is a deadly outbreak threatening the globe. I fear we will not be safe from the scourge until a vaccine is developed that can prevent governors unencumbered by scientific evidence or logic from becoming infected with Presidential ambitions.

Les Roberts – “Day 18: The Departure of Hurricane Katrina”

Les Roberts – Freetown, Sierra Leone – October 22nd, 2014

Day 18: The Departure of Hurricane Katrina

There are few upsides to this Ebola outbreak. All of us in the WHO office are working very hard to do little things (e.g. get Standard Operating Procedures in place for prioritizing different kinds of lab samples or getting a facility inspected and deemed safe enough for the Cuban Medical Brigade to work there) and we all know the sum of those little things is not even close to adequate. But, the huge upside is that I work with some astonishing people. The world has sent it’s “A Team” here and it is really flattering to get to rub shoulders with them.

I remember “sliming fish” in salmon processing factories in Alaska during the summer in the 1980’s. I worked in four of them. These were big unheated metal factories with concrete floors. There were processing lines with distinct task stations and the first major station in each line was the person who cut the head off the fish. That person would typically set the work pace for the teams of 30-50 people farther down the processing line who did other chores like ripped out the gills, cut open the body cavity… There was one guy, a guy who had not gone to college and had a humble job the rest of the year, who could cut off 100 salmon heads per minute. There were two lines of people behind him who handed him fish, he had a guillotine-type device with a V-shaped blade, operated by a foot pedal, and he would chop off the head of each fish. This was Alaska, so he had removed the Federally mandated safety guard which allowed him to go faster. He would grab a (typically seven pound) fish fed to him by a line behind him on the right with his right hand, slide it across in front of his torso and chop off the head, and then keep sliding the fish to processing line in front of him on the left side, and at the same time he would have been moving a fish with his left hand chopping a head off and passing to the other line in front of him on the right. When he was in full blast, you could not see his hands they moved so quickly and the blade made a bang, bang, bang sound that was very 1984esque. He would perform his magic for three or four minutes until huge piles of fish were backed-up at the various processing stations and then just lean back for a while, cross his arms and gloat at the workload and work frenzy he had created. He was an astonishing worker who had this one tiny niche in which he was not just excellent, but superhuman. I have seen very few humans that struck me that way through the decades: Tiger Woods at his peak, Bill Foege, the former CDC Director. There has been a gal here these past weeks in Freetown who has left today, she is equally superhuman.

Katrina, whose husband claims she is the one for which the Hurricane was named, is an Australian virologist and epidemiologist. She came to do epi but there was a need for safety training and somehow she fell into that billet. She might not be my first pick for accompaniment on a lifeboat lost at sea: she is rather high energy. Think Katherine Hepburn meets Taz.   She has so much drive that when she does not get the support she expects from her supervisors in country, she starts cc:ing the WHO Assistant Director for Ebola in Geneva. She only has one engagement level, 200%. Don’t get me wrong, she is very polite and respectful. She is less than 100 pounds and unintimidating. But, this full throttle need to engage about something is operating whether it is 7AM or 11PM or any moment in between. But, man has she been an astonishing trainer!

She arrived in Sierra Leone just as a three-day training on how to stay safe in a Red Zone was developed and the developer’s time here was up. So in she stepped. The course has a day of lectures about ebola and general infection control principles. This worked well with her virologist training. When students would ask questions she did not know, she would study at night and answer the next day digging into the most esoteric aspects of virus physiology or urine collection techniques. And days two and three are all about PPE: a little about how to get it on, but a lot about how to get it off. Again, and again, and again. They walk around outside in the sun for 45 minutes in PPE. They pass through a mock ward in the PPE. They learn about the buddy system for quality control while removing PPE. And this could be boring but with Katrina these were three days of riveting self-confidence building. Adding to it the Chief Matron nurse gave Katrina a few of her best nurses, who took the course, watched the course, and then took over the course. Over six weeks she got four teams of trainers up and going and the course trained-up over 700, mostly nurses, in Ebola safety and PPE. As of last report, none of her first cohorts has become infected. The very first cohort almost all went to the largest ETU in the country here in Freetown where they have had a lot of staff infected over the months, so these were the highest risk trainees.

Being high energy certainly helped a lot in her success, but was not the largest part. The biggest part is that she just loves engaging with trainees. I suspect you have seen this, the really really great teachers, the Sharron Schwartz and Linda Cushman types, just exude love and happiness when engaging in the process of teaching. At the breaks, Katrina was constantly going around and visiting with the attendees and getting their stories. She was tired, but this is what energized her. The trainers made a special send-off meal for her for her last day. Katrina and many of these hard, tough senior nurses who have all lost co-workers, got all teary-eyed at the send-off. It was excruciating for them to not be able to hug good bye.

Wow, is it inspiring being around people like that!

Les

Freetown 2014 © Les Roberts

Katrina with Raj Shah: Every dignitary wants their picture taken with Katrina.

Freetown 2014 © Les Roberts

Putting it on is the easy part!

Freetown 2014 © Les Roberts

Did I mention that the British Home Secretary and the New Sierra Leone Ebola Czar wanted to see Katrina in action?

Freetown 2014 © Les Roberts

Katrina Roper in her element.

Les Roberts – “Day 13: Bias, bias everywhere, but not a chance to think.”

Les Roberts – Freetown, Sierra Leone – October 17th, 2014

Day 13: Bias, bias everywhere, but not a chance to think.

Great news.  I was meant to have dinner with the two top guys here from CDC but they had to cancel to have a conference call with Tom Frieden. What a great director, what an impossible position. But, that can be a discussion for someone else’s blog. What this really means is that I have a couple free hours for the first time in days and I can write to you.

I had a great chat recently with Craig Spencer (PFMH ’2013, one of Rachel Moresky’s international emergency medicine fellows) who is with MSF in Guinea. He said that a quick scan of their data suggests that the longer between the onset of symptoms and when one shows up in the clinic, the better the chances of survival. This is of course, the opposite of the message we want to get out. This is clearly a bias issue, probably survivor bias.

CDC thinks that the median time from the onset of symptoms to death in 6 days. In Sierra Leone, we think that on average people have symptoms for seven days before coming into a health care facility. Thus, in terms of Craig’s data, with no treatment at all, if someone is on day two of symptoms, there is probably a 70ish percent chance they will die. If they show up on day ten, there is probably only a 20ish percent chance they will die. Thus, of course the longer a patient has been symptomatic when they show up at your clinic, the better the chance they will survive. But, as I said before, the primary health benefit of a patient going for treatment is not that they will get medical care and survive. The primary benefit is that they will not infect a slew of other people as they become viremic and shed via every pore and liquid in their body. I can think of no other disease with the possible exception of rabies where the number one health reason for medical care is not related to the patient. Thus, if the message got out, “the later you come for treatment the more likely you are to survive,” this would completely undermine the control efforts.

Almost everyone understands that this survivor bias is going on. There is one hospital here in town that is very proud and loud about how they have a 70+% survival rate. It does not matter which one. They are an Ebola treatment facility and patients have to be laboratory confirmed positive to get referred to this hospital. Now, it takes three to four days in Freetown to get lab results back (and a LOT of people are working on this issue). Thus, given seven days from symptoms to clinic presentation plus the lab delay, patients have been symptomatic 10-11 days without dying upon arrival at this facility… Of course, they have a 70+% survival rate. I care much more about the fact that this facility has handled a couple hundred patients and none of their clinicians have been infected. To me, this is far more impressive and more important in terms of stopping the outbreak.

There are other big biases operating as well.  Before coming, I heard repeatedly (not just from the talking heads on the television but in my WHO briefing) that this outbreak seems to have a very low case fatality rate compared to past Ebola outbreaks, perhaps 46-48%.  I strongly suspect and the evidence is building that this is just an issue of low sensitivity surveillance; and the burial surveillance is worse than the case surveillance. (That is what the CDC meeting tonight was about. I think between CDC and WHO, we will have some quantitative insight into this before long.) Likewise, I keep hearing that in Sierra Leone, this is largely an urban outbreak. While Ebola has never been in cities before and this is huge and noteworthy unto itself, I strongly suspect that this is more an issue that surveillance is almost complete (especially for burials) in the urban centers compared to the rural areas. Now it is Government policy that bodies be swabbed for testing before burials and if a body is Ebola positive, it gets entered as a case and a death, improving the surveillance sensitivity of both surveillance measures.  Burial teams are providing nearly complete coverage in Freetown and are not available in many rural areas.

I would love to spend my time assessing these things but the fact is that if the surveillance system sensitivity is 30% or the urban fraction is exaggerated by a factor of two, the strategy for controlling the outbreak is the same. In Bo and Kenema, centers of the crisis last summer, the outbreak is on the decline. They now have enough beds for referrals. They have good contact tracing (maybe 90%????) and follow-up. The message has been sent out – come for treatment early. Most bodies get buried effectively by trained teams. Where it is not the case, groups spontaneously arose and developed their own no-touch approaches which use ropes with slip-knots to move corpses. We need to get that going everywhere as we have those efforts going well only in the Eastern areas. (Also, lab testing makes the clinics function better by getting the negatives out quickly, freeing beds, protecting the non-Ebola cases and allowing contact tracing to happen…)  Time spent on improving data quality is potentially time away from getting facilities up and running. So on we run.

Freetown 2014 © Les Roberts

Ebola walk: elbows against side, fingers interlocked, as part of PPE training at National Stadium.

I hate bias!  But I am just going to have to ignore its brazen manifestations for a while.

Cheers,

Les