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Ebola Outbreak Finally Receding in Sierra Leone; CDC Modeling Was Incredibly Accurate

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Back in late September, just a week before Ebola panic hit a peak in the US when a patient in Dallas was diagnosed with the disease, the CDC produced a remarkable study in which they modeled the expected number of Ebola cases both with and without intervention. That study received a huge amount of press coverage, primarily because the model predicted that without intervention by public health authorities, as many as 1.4 million people could be infected. By contrast, with a program of isolating infected patients and educating survivors on proper burial techniques, the model showed that the outbreak would be much less widespread. The modeling projected cases through yesterday’s date, January 20.

Less reported in the media at the time was the projected number of cases under the scenario of intervention. The model predicted an actual number of cases between 25,000 and 30,000 by this week and a reported number of cases of nearly 10,000. Here are the two projections placed alongside one another:

CDC modeling of projected number of Ebola cases without (left) and with (right) improved patient isolation and safe burial practices.

CDC modeling of projected number of Ebola cases without (left) and with (right) improved patient isolation and safe burial practices.

The latest data from WHO indicate just over 21,000 cases as of January 11. That is a remarkable achievement by the team that developed the model. The observed actual number of reported cases fell squarely within the range predicted by the model. With the influx of health professionals to the region to provide care for infected patients, it seems likely to me that the correction factor applied in the CDC model to correct from the reported number of cases to the actual number would be very different now, so that the reported number and actual number would be much closer to one another, making the prediction even more accurate.

Last time I posted on progress in stopping the spread of the virus, we saw that the rate of appearance of new cases was dropping rapidly in Liberia but was still accelerating in Sierra Leone. The good news is that the improved practices have finally been implemented sufficiently in Sierra Leone that the rate is now dropping there. Here are the plots of weekly new cases in the two countries from the latest WHO Situation Report:

Weekly number of new cases of Ebola in Liberia (left) and Sierra Leone (right). Control of the virus was achieved about two months later in Sierra Leone than in Liberia.

Weekly number of new cases of Ebola in Liberia (left) and Sierra Leone (right). Control of the virus was achieved about two months later in Sierra Leone than in Liberia.

Although the battle is not yet over, all indications are that the outbreak is well past the worst phase and should end soon. Considering how closely the CDC model predicted the eventual size of the outbreak with the control measures that were implemented, it seems safe to say that the world would have witnessed a truly horrific level of spread of the virus had improved safety measures not been implemented. As of the January 14 WHO Situation Report, a total of 825 health care workers have been infected, with 493 of them dying. Without their sacrifices, many more would have been lost.

Ebola Outbreak Receding in Liberia, Still Strong in Sierra Leone

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Back in late September, the press had a field day with a mathematical model developed by CDC that estimated that if left unchecked, the Ebola outbreak in West Africa could wind up infecting over 1.4 million people. Almost missed in the hysteria over that high number was the fact that this same model predicted that even with key public health measures (patient isolation, monitoring of at-risk population who had contact with infected people and safe burial practices) falling short of 100% implementation, the outbreak could be brought under control around January of next year.

Word has been leaking out for a while now that the rate of new Ebola infections in Liberia is falling. Reports in the Washington Post on October 29 and November 3 told us as much. A chart in the WHO Situation Report for November 5 drives home just how dramatic the decline in new cases has become:

WHO Ebola Situation Report November 5, 2014

WHO Ebola Situation Report November 5, 2014

As can be seen in the chart, the rate of new infections for the two most recent weeks is less than one fourth the rate at the peak of the outbreak. Unfortunately, the news for Sierra Leone is not as good. While the rate of new infections may be leveling off, it is not yet falling appreciably:

WHO Ebola Situation Report November 5, 2014

WHO Ebola Situation Report November 5, 2014

Digging into the WHO report a bit further, we can find some evidence for how this dramatic drop in new cases has been brought about. We see that 52% of cases are now isolated. The WHO target for December 1 has been set at 70%, with a target of 100% by January 1. When it comes to management of dead bodies, though, the December 1 target has already been surpassed. WHO reports that 87% of the dead are being “managed in a safe and dignified manner” while the targets were set at 70% for December 1 and 100% for January 1. Also, although no benchmarks are reported, WHO states that 95% of registered contacts were reached daily (although in the text of the report, there are suggestions this number may be somewhat overstated).

It should come as no surprise that progress in implementing these basic measures has had a huge impact on bringing down the rate of new infections. It fits perfectly with the CDC mathematical model and it also addresses the known biology of Ebola infections. Patients are most infectious at or near death, so establishing safe burial practices is vitally important. Conversely, identifying infected individuals through daily monitoring of the at-risk population and then isolating infected individuals once symptoms begin means that far fewer people are exposed to people producing large amounts of virus.

Sadly, those who remain exposed are the health care workers who are providing care to those who are infected. Despite shortages of equipment and supplies, WHO and other organizations are doing their best to overcome those shortages and to beef up training to reduce risk to these brave people on the front lines in the work to control the virus. As of this November 5 report, 546 health care workers have been infected, with 310 of them dying. Only four new infections were reported for the week ending November 2, so it is hoped that this rate is also dropping.

Had the alarmists who insisted that this was a new super-strain of Ebola capable of airborne transmission (or even a strain developed in a bioweapons laboratory), it is doubtful that these basic public health measures would have had such a dramatic impact on the rate of new infections. Perhaps those folks can go back to railing about chemtrails or the evils of vaccines, because basic boring science appears to be on the road to controlling the current outbreak before all of mankind succumbs.

In the meantime, we are at about two weeks into the three week incubation period both for anyone “exposed” by Craig Spencer or for Kaci Hickox (or anyone she “exposed”) to show symptoms. No reports of transmission so far, and the odds of any cases showing up are dropping very rapidly from the already very low levels where they started.

CDC Director: “Zero Risk” to Passengers on Flights With Dallas Ebola Patient

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Although not yet widespread, panic and disinformation are emerging surrounding the case of the first patient to have been diagnosed with Ebola while in the United States. The worst of the hysteria surrounds the fact that Thomas E. Duncan flew from Liberia to the United States on a trip that required 28 hours, ending at the Dallas-Fort Worth airport on September 20. It is known that Duncan was screened in Liberia and found not to have a fever when he boarded the first flight. Persons infected with Ebola but not yet exhibiting symptoms are incapable of spreading the disease, primarily because the disease spreads through direct contact of mucous membranes or open wounds with bodily fluids and symptom-free patients are not yet vomiting or having diarrhea, so no virus-carrying fluids are being produced or at risk of being spread in ways that other people will come into contact with them.

On Tuesday, the Director of the CDC, Dr. Tom Frieden, stated outright that there is zero risk to passengers who were on a flight with Duncan:

A national public health official today said there was “zero risk of transmission” of Ebola on a commercial airline flight that a Dallas patient who has tested positive for the disease flew on from Liberia earlier this month.

Centers for Disease Control and Prevention Director Tom Frieden said today in a live briefing from Atlanta that the person — a male who remained unnamed — showed no symptoms before boarding the plane and was not contagious. The CDC doesn’t “believe there is any risk to anyone who was on the flight at that time,” he said.

Despite Frieden’s clear statement that other passengers face no risk, the press continued to hound CDC and the airlines until Duncan’s itinerary was released. While CBS was moderately responsible in their coverage of the flight information, the Daily Mail asked breathlessly in their headline whether YOU were on a flight with Duncan. Even more incredibly, stocks in US airlines were dumped yesterday in response to the news of Duncan’s flights:

Investors were also selling stocks following news that the first case of Ebola had been diagnosed in the U.S. Investors dumped airline stocks and bought a handful of drug companies working on experimental Ebola treatments.

The story of just how Duncan became infected is a sad one. On September 15 (recall that he left Liberia on the 19th and arrived in Dallas the 20th), Duncan helped neighbors take their 19-year-old daughter to the hospital. Sadly, the hospital was already overwhelmed with patients and she was turned away, only to die early the next morning after returning:

In a pattern often seen here in Monrovia, the Liberian capital, the family of the woman, Marthalene Williams, 19, took her by taxi to a hospital with Mr. Duncan’s help on Sept. 15 after failing to get an ambulance, said her parents, Emmanuel and Amie Williams. She was convulsing and seven months pregnant, they said.

Turned away from a hospital for lack of space in its Ebola treatment ward, the family said it took Ms. Williams back home in the evening, and that she died hours later, around 3 a.m.

Mr. Duncan, who was a family friend and also a tenant in a house owned by the Williams family, rode in the taxi in the front passenger seat while Ms. Williams, her father and her brother, Sonny Boy, shared the back seat, her parents said. Mr. Duncan then helped carry Ms. Williams, who was no longer able to walk, back to the family home that evening, neighbors said.

The hospital in Dallas where Duncan is being treated has received a lot of criticism because he first went there on September 26 but was sent home when only exhibiting a low grade fever:

When Mr. Duncan first arrived at the hospital last Friday, six days after he had arrived in America, he told a nurse that he had come from West Africa. Public health officials have been urging doctors and nurses to be on the alert for Ebola in anyone who has been in Guinea, Liberia or Sierra Leone. But information about Mr. Duncan’s travel was not “fully communicated” to the full medical team, said Dr. Mark Lester, executive vice president of Texas Health Resources, the parent organization that oversees Texas Health Presbyterian Hospital.

As a result, that information was not used in the clinical diagnosis and Mr. Duncan was sent home, with the diagnostic team believing he simply had a low-grade fever from a viral infection, Dr. Lester said.

Those with whom Duncan had contact from the time of the onset of his symptoms until he returned the hospital on September 30 28 (corrected; September 30 was when tests confirmed Ebola after he returned to the hospital on September 28) in much worse condition and was then isolated are being monitored for signs that they may be infected:

Officials said Wednesday that they believed Mr. Duncan came into contact with 12 to 18 people when he was experiencing active symptoms and when the disease was contagious, and that the daily monitoring of those people had not yet shown them to be infected.

The incubation period (the time between exposure to the disease and the onset of symptoms in an infected person) for Ebola varies from 2 to 21 days. Recall that Duncan was exposed on September 15 and visited the hospital for the first time on September 26, so his incubation period was around eleven days. We are now around six days into the time since Duncan first visited the hospital, so those with whom he came into contact will need to be monitored for for another two weeks or so until at least 21 days have passed since their last contact with Duncan.

While there is some chance that one or more of those with whom Duncan had contact while he was contagious will become infected, as long as everyone who was in contact with him during that critical period is under observation now, there is virtually no chance of the disease spreading outside that small group of people. And you can rest assured that nobody from any of the flights Duncan was on will come down with disease from exposure to him.

No, We Aren’t All Going to Die Because Ebola Patients Are Coming to US for Treatment

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Scary, color-enhanced electron micrograph of Ebola virus particles. Creative Commons license courtesy of Thomas W. Geisbert, Boston University School of Medicine.

With the death toll now over 700 in an Ebola outbreak that has been building since February, Americans are suddenly up in arms about the virus, but only because it was announced yesterday that up to two Americans infected with the virus may be transported to Atlanta for treatment. Yes, the virus is especially deadly, with a death rate of 70-90% of infected patients, but the virus does not spread particularly efficiently and is not airborne. Writing at CNN.com, biologist Laurie Garrett points out a disaster scenario for the virus. Rather than an outbreak in the US, which seems extremely unlikely, Garrett outlines how the virus could spread in the much more densely populated Nigeria rather than the more remote areas of Guinea, Sierra Leone and Liberia where it is now concentrated.

Before getting into the details of the current outbreak and its possible spread to Nigeria, a little background on the virus. From the World Health Organization, we have this information on how the virus spreads:

Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals. In Africa, infection has been documented through the handling of infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest.

Ebola then spreads in the community through human-to-human transmission, with infection resulting from direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and indirect contact with environments contaminated with such fluids. Burial ceremonies in which mourners have direct contact with the body of the deceased person can also play a role in the transmission of Ebola. Men who have recovered from the disease can still transmit the virus through their semen for up to 7 weeks after recovery from illness.

Of particular relevance to the two patients who may be transported to Atlanta for treatment (they work for Samaritan’s Purse, an aid organization) and the tragic death of Sheik Umar Khan, Sierra Leone’s top Ebola doctor, the information from WHO continues:

Health-care workers have frequently been infected while treating patients with suspected or confirmed EVD. This has occurred through close contact with patients when infection control precautions are not strictly practiced.

The fact that these health care givers become infected because standard infection control precautions are not strictly practiced in no way should suggest that they are uninformed or careless. Instead, Garrett points out in her article the stark realities facing health care providers in the three countries where the outbreak rages:

To show how ill-equipped these nations are to battle disease, per capita spending on health care, combining personal and governmental, amounts to only $171 a year in Sierra Leone, $88 a year in Liberia and $67 a year in Guinea, according to the Kaiser Foundation.

For those who want more detail on the virus, this succinct summary of the structure of the Filovirus family of viruses and their mode of operation is very informative.

For the panic-motivated hypochondriacs among us, initial symptoms of this virus mimic the onset of most other viral infections.

The most recent update from WHO on the outbreak can be read here. The update summarizes the assistance that is being provided to the countries where the outbreak is ongoing. Significantly, WHO is not advocating travel restrictions at this time.

Returning to Garrett’s article, she points out the factors that would lead to chaos should Ebola spread in Nigeria:

Were Ebola to take hold in that country [Nigeria], spreading from person-to-person in a densely populated, chaotic city such as Lagos, the worldwide response would swiftly spin into uncharted political and global health territory.

Consider the following: Nigerian physicians are on strike nationwide; hundreds of girls have been kidnapped from their schools and villages over the past six months by Boko Haram Islamist militants — and none has been successfully freed from their captors by the Abuja government.

Nigeria is in the midst of national election campaigning. President Goodluck Jonathan’s government is, at best, weak. The nation is torn apart by religious tension, pitting the Muslim north against the Christian south. Islamists in the north have long distrusted Western medicine. They have opposed polio vaccination and have kidnapped and assaulted central government health providers.

Garrett’s plea is for an already-planned African summit on Monday to be used to develop a coordinated plan for dealing with the virus:

One way or another, Obama must take advantage of Monday’s Africa summit to press the case for calm and appropriate responses. These would include specific post-Ebola financial commitments to Liberia, Sierra Leone and Guinea.

The possibility that the epidemic might take hold in Nigeria must be confronted, and plans of action must be considered. The world cannot afford to make decisions in the heat of panic about such things as international airport closures, withdrawal of foreign oil workers, negotiations for outbreak responses with northern imams, hospital and clinic infection control training across thousands of Nigerian health facilities, deployment of international assistance teams for rapid diagnostics and lab assistance and countless other contingencies.

Sadly, Garrett points out important information on the damage that has already been done in this outbreak:

When this Ebola epidemic eventually ends, the health budgets of these nations [Liberia, Sierra Leone and Guinea] will have been bankrupted, and many of their most skilled and courageous physicians, nurses, Red Cross volunteers and hospital workers will have perished.

Let’s hope that Monday sees the beginning of stronger coordination to put more resources where they are needed to halt the spread of this ongoing disaster.

The Comey College Of Prosecutorial Knowledge

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This one is for Mary, who sent me the link from the road. As everyone knows, once you earn your bones in the Bush DOJ on torture and/or illegal wiretapping, you get a plum position in the private world. As Mary has consistently pointed out, Jim Comey got jumped in to the gang that couldn’t torture straight when he invoked state secrets to cover for Larry Thompson and other malfeasants in the Maher Arar case. For that fine work, Comey is now General Counsel at Lockheed Martin Aerospace while Thompson had to settle for the General Counsel slot at PepsiCo. But today is about Comey’s current crew, Lockheed.

The Wall Street Journal has an article out describing the fine educational possibilities provided the world community by the American military-industrial complex:

Lockheed Martin Corp. became the nation’s No. 1 military contractor by selling cutting-edge weaponry like the F-35 Joint Strike Fighter.

Its latest contribution to the U.S. arsenal: training prosecutors in Liberia’s Justice Ministry.

The U.S. government has hired the defense contractor to test an emerging tenet of its security policy. Called “smart power,” it blends military might with nation-building activities, in hopes of boosting political stability and American influence in far-flung corners such as Liberia.

Yep, the makers of strike fighters, cruise missiles and other niceties of global thermonuclear war, are gonna school up the new justice class in Liberia. Really, what could go wrong??

Defense firms are eager to oblige. “The definition of global security is changing,” says Lockheed’s Chairman and Chief Executive Robert Stevens. He wants the maker of the Air Force’s most advanced fighters to become a central player in the U.S. campaign to use economic and political means to align countries with American strategic interests.

Last year, Lockheed had two of its highest profile programs, the F-22 Raptor fighter and a fleet of presidential helicopters, ended by the Obama administration. Now, Lockheed is one of several defense firms expected to bid for a State Department contract to support “criminal justice sector development programs world-wide,” that could be worth up to $30 billion over five years.

Well, that does seem like a promising business opportunity and, hey, why should Halliburton and Blackwater/Xe get all the fun and Ferengi profit?

Morgan Stanley defense analyst Heidi Wood says Lockheed’s early push into this realm sets it apart from competitors. It is too soon to pinpoint a financial impact, she says, but the moves will pay off. “It’s a complete paradigm change.”

Yeah, ya think?? I wonder what kind of homework the Lockheed law professors assign? Read the entire WSJ article, it is worth it.

Now, to be fair, Jim Comey is not specifically referenced in the comprehensive article, but there is little question but that he is the top prosecutorial experience Lockheed possesses and, really, a joint with the history of Liberia would be the perfect place for former Bush/Cheney prosecutors to impart their “special” skills. It could all fit so nicely.