Learnings from Ebola epidemic

Excerpts from MSF’s Ebola-related research, highlighting the various operational challenges during the epidemic and MSF’s measures to tackle them

The Ebola outbreak in West Africa was the most significant medical challenge that Médecins Sans Frontières (MSF) faced between 2014 and 2015. There were a series of medical and logistical challenges to prevent infections and manage Ebola patients, and there was very little scientific knowledge to back decisions up.

As of February 2016, 28,603 people had been infected and 11,301 patients died in the three most affected countries of Sierra Leone, Guinea and Liberia. A limited number of additional cases were reported in Nigeria, Mali, the US , Senegal, the UK, Spain and Italy due to the repatriation of infected citizens by medical evacuation and persons entering countries well and then becoming sick from the virus causing further spread among close contacts.

Two years after the Ebola outbreak was declared in Guinea, MSF has published a review of its Ebola-related research including clinical, epidemiological and anthropological research. During the outbreak, MSF cared for more than 5200 Ebola confirmed patients, of which 2500 patients survived the disease.

The epidemic can be divided into four phases. The first phase was from December 2013 to March 2014, during which the first infections occurred in a remote region of Guinea. The inadequate health infrastructure present and the first time appearance of the virus in this region resulted in cases presenting unrecognised and therefore spread occurred undetected.

The second phase from March to July 2014 heralded the confirmed spread of Ebola to the neighbouring countries of Liberia and Sierra Leone.  During this phase hundreds of healthcare workers became infected and died from the virus.

The third phase of the outbreak from August to December 2014 saw an exponential rise in the number of cases across the three most affected countries, including for the first time outbreaks in major urban settings.  On August 8, the Director-General of the World Health Organization (WHO) declared the Ebola outbreak a public health emergency of international concern. The fourth phase, from December 2014 to January 2016 was characterised by decreasing numbers of new cases. This was achieved through a combination of community, national and international efforts.

MSF used six pillars in its approach to tackle the outbreak:

• Isolation of cases and supportive medical and mental health care in dedicated ETC’s
• Contact tracing
• Awareness raising in the community
• A functioning surveillance and alert system
• Safe burials and house spraying
• Maintaining healthcare for non-Ebola patients

However, this Ebola outbreak posed many challenges, not only for MSF but also for other actors involved in the response. An analysis on the operational challenges and the measures adopted by MSF to tackle them.

Recording patient information: Recording clinical notes in an ETC was a complex process. Paper-based records were completed by staff in the high risk zone while attending patients but these paper records could not be sent to the low risk zone for review and entry onto a database because of the risk of transmitting infection. As a result staff from the high risk zone had to shout the results of ward rounds across the fence to staff in the low risk zone on the other side who recorded the information on clean paper. This process was slow and sometimes inaccurate, which led MSF to trial a scanning system based on mobile phones mounted on custom made stands and positioned in strategic places across the ETC. Clinical notes from the high risk zone could then be scanned and transmitted over a secure wireless network to a printer in the low risk area. This new method improved the quality of data being collected and reduced the time required for transmitting information. Additionally, infection risks were minimised. In Liberia, MSF staff commenced using personal digital assistants (PDA) to record clinical information during ward rounds in the high risk zone. This information could then be transmitted in real time to the medical office in the low risk zone, negating the need for paper. It was found that PDA’s reduced the overall time staff had to spend recording information during ward rounds. The novel use of technology for recoding information is dependent on having appropriate technical expertise available to fix it should it fail in an emergency humanitarian setting.

Laboratory testing: The traditional way of diagnosing Ebola involved taking a blood sample from the patient using a needle and syringe (venipuncture). This blood sample was then tested for the Ebola virus using a technology called polymerase chain reaction (PCR). Sometimes healthcare staff found it very difficult to obtain a blood sample by venipuncture from very young children who were also dehydrated. Occasionally patients refused to have venipuncture performed due to religious or cultural reasons. Staff that carried out this procedure while wearing personal protective equipment (PPE) were also at risk of needle stick injuries that could in turn cause them to become infected with the virus. Fingerstick tests are used to check patient’s for malaria by making a small puncture in the skin of the fingertip with a lancet and then squeezing out a drop of blood for analysis. Fingerstick blood samples are much easier, faster and safer to take than venipuncture samples. MSF questioned whether fingerstick samples could be used instead of venipuncture for diagnosing EVD in ETC’s. MSF staff in Guinea collected data on patients being screened for admission using both venipuncture and fingerstick blood tests and found that fingerstick samples were able to detect 87 per cent of the Ebola cases confirmed using venipuncture samples. As a result of this research it was recommended that fingerstick blood sampling, while less accurate than venipuncture for diagnosing Ebola, could be used in situations where it was not possible to perform venipuncture. The PCR test used to diagnose EVD is very accurate, that is, it is very good at identifying those people who have Ebola, while excluding those who have not. Very rarely, the PCR test can give incorrect results. MSF in collaboration with other organisations produced research that highlighted an Ebola case in Monrovia with a false negative PCR result.

A false negative result occurs when the PCR test indicates that the virus is not present while in reality it is. Research such as this underscores the need to always interpret test results in combination with the clinical and epidemiological history of each patient. Regarding the PCR test for Ebola, the time taken between obtaining a blood sample and getting a result can be considerable. This is due to a number of factors including the location of the laboratory in relation to the ETC. MSF assessed the feasibility of using a different Ebola test (called the Xpert Ebola Assay) and locating the testing device within the ETC. It was found that using the Xpert Assay compared to traditional PCR testing reduced the waiting time between sampling and result notification by over 50 per cent. This is a significant improvement in turnaround time for test results especially for those patients waiting in the suspect area to be admitted or discharged.

Triage: When patients first arrived at an MSF ETC, a doctor or nurse at triage assessed them. This step was used to figure out which patients presenting were likely to have Ebola or not. Those who met the criteria of a suspect case using the WHO/MSF case definition were admitted to the suspect area of the ETC for blood testing. Individuals not fulfilling the case definition were discharged from triage.  If the triage step was not carried out appropriately with an accurate case definition, then some potentially infected persons could be sent home while non infected ones could be admitted to the suspect area. Such a scenario posed a threat for further spread of the virus. MSF contributed to research that investigated which combination of clinical signs and history of contact best discriminated between cases and non – cases. What is especially lacking is an accurate point of care Ebola diagnostic test that staff could use in the suspect area to find out there and then if a patient has Ebola or not.

Infection control: Preventing the spread of Ebola virus within the ETC’s to staff and other personnel was a priority during the outbreak. Strict procedures were put in place to ensure MSF staff had access to PPE and appropriate training on how to put it on and remove it in a safe manner. The minimum level of PPE that is required when treating Ebola patients is still not fully understood. In general, the higher the level of PPE, the more difficult it is for staff to attend patients in tropical environments due to heat illness. MSF participated with a number of organisations to explore what the optimal PPE should be and this research is ongoing at present.
Infection control was critical for patients admitted from triage into the suspect area of the ETC. While in the suspect area, patients had blood tests performed to check for the presence of Ebola with a positive test causing the patient to be admitted to the confirmed ward of the ETC and a negative test resulting in discharge from the facility. Therefore within the suspect area, there were patients with and without Ebola present at the same time. If infection control measures were poor in the suspect area, it is possible that negative cases awaiting blood test results could contract the virus from positive cases also awaiting test results. MSF researched this important issue and found there was no evidence of it occurring in MSF ETCs. Plexiglass partitions were introduced to ETCs during the outbreak. This allowed staff to assess how patients were progressing without having to put on PPE. The plexiglass partitions facilitated greater interaction between patients and staff and also strengthened infection control measures within ETCs.

It is not only in ETCs were infection control was important. During the height of the outbreak in Monrovia, when there was no bed availability in ETCs, MSF decided to distribute over 65,000 Ebola protection and disinfection kits to households, frontline workers and other targets in the poorest areas of the city. These kits included a bucket, chlorine, surgical gown, mask and gloves and were to be used while caring for any sick person in the community or to handle any dead body while awaiting the ambulance to arrive. The kits were essentially a way of creating infection control procedures in the community at a time when there was no bed availability in ETC’s. In close association with the distribution of the kits, MSF carried out intensive health promotion activities in the community to ensure people understood how and when the kits should be used.

MSF follow up research indicated that 99 per cent of community respondents agreed that the kits were useful and had no problem using them. The Hazard Analysis of Critical Control Points (HACCP) is a tool used in other disciplines such as the food sector to prevent contamination by biological or environmental material.

MSF in association with other researchers found that the HACCP protocol could potentially be used in the community setting as an infection control measure to reduce the risk posed by human waste in areas of Ebola transmission.

Way forward

This Ebola outbreak and all previous ones have shown the  urgent need for accurate rapid diagnostic tests, effective treatments and a working vaccine. International research institutions must continue to prioritise these areas of investigation even though this outbreak has ended. Now is also the appropriate time to agree ethical clinical trial protocols for the next humanitarian/ medical emergency. Finally, how the international community can better respond to a major infectious disease outbreak is an area of research that needs to be urgently addressed.

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