Image credit: Wikimedia

On Tuesday of last week (8th May) the WHO officially declared a new outbreak of the Zaire strain of the Ebola Virus Desease (the deadliest of the five Ebola strains) in the Democratic Republic of the Congo (DRC).

This current outbreak has, as of yesterday, lead to at least 25 deaths from around 45 suspected or confirmed cases [1].

The DRC is no stranger to Ebola, containing as it does the river for which the disease was named after [2] during its discovery in 1973*. This will be the 9th outbreak the country has seen since then [3], each of which had the potential to lead to an outbreak with similar devistating results as the 2014/15 West African outbreak.

With a long incubation period of 21 days Ebola is a particularly troublesome virus to bring under control. Once infected an individual can travel a great distance before becoming symptomatic. The initial response to this outbreak has been rapid [4] however this sadly has not stopped the virus from spreading the 80 miles from its origins in Bikoro to the urban populations of Mbandaka (population=1.2 million).

For an outbreak to officially be classified as having ended the WHO requires 42 days (2 incubation cycles) of no confirmed cases, starting from the previous confirmed case. No easy feat, even under ideal circumstances.

During an outbreak the emergency response effort has a number of cards they can play to curb the spread of the disease. For the current outbreak they appear to be throwing everything they have on the table, so I thought it’d be a good time to run through what we’re holding. In my opinion us humans are all in this together on this one. So it’s going to be "us" and "we" from here on out.

1. Contact tracing

Even with all the wondrous technologies that life in 2018 allows us, one of our most effective means of Ebola control is still simply talking to people. Information is scarce in remote rural outbreaks and misinformation is plentiful in urban outbreaks, as of this week it’s been confirmed that we’re dealing with both.

Contact tracing is the process by which patents, confirmed or suspected, with ebola are interviewed to determine all of the individuals the patient has been in contact with while sick. These ‘contact-peoples’ are then monitored for the next 21 days (one incubation period) for signs of the disease, if these are shown they are similarly placed in isolation and the process starts again (see here for an illustration of the process).

This may sound simple but speedy identification of infected individuals allows for immediate isolation, testing and care, preventing further individuals from becoming infected, potentially saving infected individuals lives (I say potential, as even when care is received the case fatality rate of a patient with ebola is still approximately 50%) and essential data to be collected.

Challenges with contact tracing

Contact tracing is a very human process and as such the challenges are wonderfully human to match. If funding is not an issue (contact tracing is person-hour expensive, but, thankfully, for the sake of this outbreak funds do not seem to be a limiting factor as of yet) distrust, stigma and general logistics are the three main challenges [5].

Distrust:- Imagine a situation where strangers, that don’t look like you, don’t dress like you and don’t have a good grasp on your language, entering your community, ask you lots of question, put your name on a list, take your friends and family member away to a compound where half the people that enter die and don't even allowed you the body back to bury and properly morn. In areas where there is a limited understanding of Ebola, this is how contact tracing may be perceived. With this perception distrust is a highly logical and rational response.

Stigma:- Being labeled as a contact-person and as possibly having ebola can lead to being ostracized from the community and, in the nightmare scenario, may occasionally lead to people fleeing out of shame.

Logistics:- Excellent, the patient completely cooperated! You have the names of three individuals they have been in contact with, however for one of them you have no address, no phone number and the person has gone to the local town to work for the week. How are you going to track them down? Also there is no national identification program. Good luck!

2. Isolation and quarantine

The one factor on our side when it comes to the control of Ebola is its method of transmission. Ebola can only be transmitted through bodily fluids: blood, saliva, mucus, vomit, feces, sweat, tears, breast milk, urine, semen, and vaginal fluids. So just being in the same room with someone will not necessarily mean the virus being passed on (unlike with, for example, measles. Cough in an elevator and it’s there to infect people for a couple of hours). As such a careful isolation and quarantine strategy is a highly effective means of control.

Soon after an outbreak is reported temporary Ebola treatment units are set up to facilitate this procedure. The typical setup involves two separate high-risk zones, one for those with suspected cases of Ebola and one with confirmed cases. When symptomatic individual are first brought into the facility they stay in the suspected-cases ward and if they are confirmed to have Ebola they’re moved to the confirmed-cases ward. Within both sections staff enter wearing personal protective equipment (PPE) and are sanitized as they leave (a full diagram of the set up and logistical issues can be seen here.

While there is no cure for Ebola, death often occurs due to extreme dehydration so keeping patients hydrated by providing intravenous fluids (IV) and balancing electrolytes can improve survival rates. In the, sadly all to common, event of a death from the disease the unit functions as a safe burial center where further infection is avoided [6].

Challenges with isolation and quarantine

Ebola starts with flu like symptoms:- … but so do many other diseases (e.g. malaria). Certainty of Ebola is difficult, the two seperate high-risk zones are intended to mitigate the likelihood of accidentally infecting a false positive patient with Ebola but the risk is still present.

Delivering healthcare in a scuba suit:- The PPE gear is restrictive. There are goggles that fog up, a hood and cowl that impede hearing and double gloves that make inserting an IV like the cruelest of fairground games. It also gets incredibly hot in there (around 37 degrees centigrade), meaning that they can only be worn for around an hour maximum. There are stories of healthcare workers pouring out liters of of sweat when they exit. [7]

Supplies:- As difficult as the PPE gear is you really don’t want to go without it! An Ebola treatment unit needs a constant supply of disposable elements such as gloves as well as disinfectant and biological hazard disposal bags. In rural, difficult to reach areas these may end up in short supply.

3. The new Ebola vaccine

On Wednesday (15th May) 4300 doses of the new ebola vaccine arrived in DRC [8]. With the snapy name of rVSV-ZEBOV, the vaccine has proven safe and (100%) effective in trials however has yet to receive full licensing. This will be the first time the vaccine has been used as a control tool in outbreak setting.

Is it a good idea to use a vaccine while it’s still technically experimental? I hear you I ask. In this case I, and the WHO, argue yes.

The basic science, and even primate testing, was completed over a decade ago [9.] However lack of any interests from the big pharmaceutical companies prevented the research going any further due to its expenses. It’s a cruel twist of fate that people cite the profits of “big pharma” for a reason not to vaccinate here in high income countries [10] when a vaccine for a disease such as Ebola is neglected due to the lack of money it would generate for the same big pharma.

This, thankfully, all changed after the wake up call that was the 2014/15 outbreak, likely due to the virus becoming a threat to high income countries for the first time (imo). The vaccine was subsequently studied in several human trials involving more than 16,000 volunteers across Europe, Africa and the United States [11]. A trial at the tail end of the outbreak enrolled nearly 12 000 people from Guinea and Sierra Leone. Of the 5,837 people who received the vaccine, no Ebola cases were recorded. By comparison, 23 cases were reported within the control arm of the trial that had not received the vaccine [12]

With these promising results the WHO have decided that “compassionate use” of the vaccine should be allowed, as at the current level of evidence it would be unethical not to offer the vaccine. Uptake is voluntary and regardless of if an individual chooses to accept the vaccine or not they will be offered medical treatment if required (i.e. no nudge tactics) [11].

Ring vaccination (rather than mass vaccination) appears to be the most effective use of the limited supply as the situation currently stands. This will involve the vaccination of healthcare workers and those identified through contact tracing being given priority in order to prevent the virus spreading through the most likely pathways.

Challenges with the new Ebola vaccine

The cold chain in a hot country:- To remain safe and effective the vaccine is required to be kept at -60 to -80 degrees Celsius. Liquid nitrogen and insulation are the key but with poor refrigeration at healthcare facilities and a dense forest landscape to navaget in the rural areas this will be a challenge. I currently have not read if the Air Bridge is able to accomidate vaccine delivery, if it is this would be a partial solution to this challange

Cultural barriers to informed consent:- How do you know if a vaccine participant understands fully their rights and the risks associated with vaccination? Informed consent can be problematic when everyone speaks the same language. When they don't, the challenge to remain ethical ramps up.

4. Educating the community

An outbreak is only brought under control when each infected individual infects, on average, less than one other individuals. The above three approaches aim to reduce the spread of the virus. Effective communication within a community make these processes possible and also may prevent additional infection through individuals changing their own behaviour accordingly.

Image credit: Pixnio

Science alone will not put a halt to the current outbreak, social scientists, and especially anthropologists [13], are crucial members of our response to this outbreak. If communication breaks down, the virus spreads. If our messages spread faster than the virus, are listened to and acted on, we have a chance to stop it in its tracks before it becomes another international catastrophe.

A note of hope to end with

As you can see there are a lot of challenges to overcome in order to bring this outbreak of Ebola under control. It is no easy task. The WHO were criticised greatly for their slow response to the 2014/15 outbreak. This cannot be argued to be the case with the current outbreak. We learnt a lot from that outbreak and what we learnt can be seen being employed today.

This, for me at least, is a reason to be optimistic, but not a reason to be overconfident and complacent. As a zoonotic virus (it has an animal reservoir) Ebola will always be on the congos doorstep ready to spark another outbreak. The best long term solution is planning and investment in the existing healthcare system, building its capacity so that the next outbreak can be responded to even quicker, and the sick can be securely treated within a well resourced hospital setting.

If you are interested in this topic and would like to help there is likely not a great deal you can do in regards to the current outbreak however you could be instrumental to the prevention of the next outbreak.

How can you help?

1. Study for a career in global public health:- The high impact careers advice group 80 000 hours has a lot of great advice if you want to join other making the world a better place through a career in global health. Read their health in poor countries article here

2. Donating to charities such as partners in health:- I’m a big fan of the charity Partners in Health. Last year The New Yorker wrote a wonderful long read interview with director of Partners in Health Ophelia Dahl (yes Roald Dahl’s daughter). Read it, its spectacular and exactly the reason why I love being around public health peoples.

Footnotes

*Named as such so that the village where the virus was originally found would not bear the stigma of the disease.

About me

My name is Richard, I blog under the name of @nonzerosum. I’m a PhD student at the London School of Hygiene and Tropical Medicine. I write mostly on Global Health, Effective Altruism and The Psychology of Vaccine Hesitancy. If you’d like to read more on these topics in the future follow me here on steemit or on twitter @RichClarkePsy.

References

[1] The World Health Organisation: Statement on the 1st meeting of the IHR Emergency Committee regarding the Ebola outbreak in 2018

[2] The Spectator: How Ebola got its Name

[3] The World Health Organisation: The history of Ebola in the Democratic Republic of Congo

[4] Stat News: As Ebola flares once again, a rapid global response invites cautious hope

[5] Greiner AL, Angelo KM, McCollum AM, Mirkovic K, Arthur R, Angulo FJ. Addressing contact tracing challenges—critical to halting Ebola virus disease transmission. International Journal of Infectious Diseases. 2015 Dec 1;41:53-5.

[6] Wilson, D. (2015). CE: Inside an Ebola Treatment Unit A Nurse's Report. AJN The American Journal of Nursing, 115(12), 28-38.

[7] Pallister-Wilkins P. Personal Protective Equipment in the humanitarian governance of Ebola: between individual patient care and global biosecurity. Third World Quarterly. 2016 Mar 3;37(3):507-23.

[8] The World Health Organisation: Ebola virus disease – Democratic Republic of the Congo

[9] Vox: We finally have an Ebola vaccine. We’re about to use it in an outbreak

[10] Attwell K, Leask J, Meyer SB, Rokkas P, Ward P. Vaccine rejecting parents’ engagement with expert systems that inform vaccination programs Journal of bioethical inquiry. 2017 Mar 1;14(1):65-76.

[11] The World Health Organisation: Frequently asked questions on Ebola virus disease vaccine

[12] Henao-Restrepo AM, Longini IM, Egger M, Dean NE, Edmunds WJ, Camacho A, Carroll MW, Doumbia M, Draguez B, Duraffour S, Enwere G. Efficacy and effectiveness of an rVSV-vectored vaccine expressing Ebola surface glycoprotein: interim results from the Guinea ring vaccination cluster-randomised trial. The Lancet. 2015 Sep 4;386(9996):857-66.

[13] The Ebola Response Anthropology Platform