Transferring patients with Ebola by land and air: the British military experience

A Historical Review of Military Medical Strategies for Fighting Infectious Diseases: From Battlefields to Global Health

The environmental conditions generated by war and characterized by poverty, undernutrition, stress, difficult access to safe water and food as well as lack of environmental and personal hygiene favor the spread of many infectious diseases. Epidemic typhus, plague, malaria, cholera, typhoid fever, hepatitis, tetanus, and smallpox have nearly constantly accompanied wars, frequently deeply conditioning the outcome of battles/wars more than weapons and military strategy. At the end of the nineteenth century, with the birth of bacteriology, military medical researchers in Germany, the United Kingdom, and France were active in discovering the etiological agents of some diseases and in developing preventive vaccines. Emil von Behring, Ronald Ross and Charles Laveran, who were or served as military physicians, won the first, the second, and the seventh Nobel Prize for Physiology or Medicine for discovering passive anti-diphtheria/tetanus immunotherapy and for identifying mosquito Anopheline as a malaria vector and plasmodium as its etiological agent, respectively. Meanwhile, Major Walter Reed in the United States of America discovered the mosquito vector of yellow fever, thus paving the way for its prevention by vector control. In this work, the military relevance of some vaccine-preventable and non-vaccine-preventable infectious diseases, as well as of biological weapons, and the military contributions to their control will be described. Currently, the civil-military medical collaboration is getting closer and becoming interdependent, from research and development for the prevention of infectious diseases to disasters and emergencies management, as recently demonstrated in Ebola and Zika outbreaks and the COVID-19 pandemic, even with the high biocontainment aeromedical evacuation, in a sort of global health diplomacy.

Air Quality Monitoring During High-Level Biocontainment Ground Transport: Observations From Two Operational Exercises

OBJECTIVE

Stretcher transport isolators provide mobile, high-level biocontainment outside the hospital for patients with highly infectious diseases, such as Ebola virus disease. Air quality within this confined space may pose human health risks.

METHODS

Ambient air temperature, relative humidity, and CO₂ concentration were monitored within an isolator during 2 operational exercises with healthy volunteers, including a ground transport exercise of approximately 257 miles. In addition, failure of the blower unit providing ambient air to the isolator was simulated. A simple compartmental model was developed to predict CO₂ and H₂O concentrations within the isolator.

RESULTS

In both exercises, CO₂ and H₂O concentrations were elevated inside the isolator, reaching steady-state values of 4434 ± 1013 ppm CO₂ and 22 ± 2 mbar H₂O in the first exercise and 3038 ± 269 ppm CO₂ and 20 ± 1 mbar H₂O in the second exercise. When blower failure was simulated, CO₂ concentration exceeded 10 000 ppm within 8 minutes. A simple compartmental model predicted CO₂ and H₂O concentrations by accounting for human emissions and blower air exchange.

CONCLUSIONS

Attention to air quality within stretcher transport isolators (including adequate ventilation to prevent accumulation of CO₂ and other bioeffluents) is needed to optimize patient safety.

Long-Distance Aeromedical Transport of Patients with COVID-19 in Fixed-Wing Air Ambulance Using a Portable Isolation Unit: Opportunities, Limitations and Mitigation Strategies

Introduction

Aeromedical transport of patients with highly−infectious diseases, particularly over long distances with extended transport times, is a logistical, medical and organizational challenge. Following the 2014–2016 Ebola Crisis, sophisticated transport solutions have been developed, mostly utilizing large civilian and military airframes and the patient treated in a large isolation chamber. In the present COVID−19 pandemic, however, many services offer aeromedical transport of patients with highly−infectious diseases in much smaller portable medical isolation units (PMIU), with the medical team on the outside, delivering care through portholes.

Methods

We conducted a retrospective review of all transports of patients with proven or suspected COVID−19 disease, transported by Jetcall, Idstein, Germany, between April 1 and August 1, 2020, using a PMIU (EpiShuttle, EpiGuard AS, Oslo, Norway). Demographics and medical data were analyzed using the services’ standardized transport protocols. Transport−associated challenges and optimization strategies were identified by interviewing and debriefing all transport teams after each transport.

Results

Thirteen patients with COVID−19 have been transported in a PMIU over distances up to 7,400 kilometers (km), with flight times ranging from 02:15 hours to 11:10 hours. We identified the main limitations of PMIU transports as limited access to the patient and reduced manual dexterity when delivering care through the porthole gloves and disconnection of lines and tubes during loading and unloading procedures. Technical solutions such as bluetooth−enabled stethoscopes, cordless ultrasound scanners and communication devices, meticulous preparation of the PMIU and the patient following standardized protocols and scenario−based training of crew members can reduce some of the risks.

Discussion

Transporting a patient with COVID−19 or any other highly infectious disease in a PMIU is a feasible option even over long distances, but adding a significant layer of additional risk, thus requiring a careful and individualized risk−benefit analysis for each patient prior to transport.

Experience repatriation of citizens from epicentre using commercial flights during COVID-19 pandemic

BACKGROUND

During the COVID-19 pandemic, many countries instituted closure of borders from international and local travels. Stranded citizens appeal to their governments to embark on citizen repatriation missions. Between February and April 2020, the Government of Malaysia directed repatriation of its citizens from China, Iran, Italy and Indonesia. We describe the preparation and execution of the repatriation mission using chartered commercial aircraft. The mission objectives were to repatriate as many citizens based on aircraft capacity and prevent onboard transmission of the disease to flight personnel.

RESULTS

Five repatriation missions performed was led by the National Agency for Disaster Management (NADMA) with the Ministry of Health providing technical expertise. A total of 432 citizens were repatriated from the missions. The operations were divided into four phases: the pre-boarding screening phase, the boarding and in-flight phase, the reception phase and the quarantine phase. The commercial aircraft used were from two different commercial airlines. Each mission had flight crew members between 10 and 17 people. There were 82 positive cases detected among the repatriated citizens. There was a single positive case of a healthcare worker involved in the mission, based on the sample taken on arrival of the flight. There were no infections involving flight team members.

CONCLUSION

Medical flight crew must be familiar with aircraft fittings that differ from one commercial airline to another as it influences infection control practices. A clear understanding of socio-political situation of a country, transmission routes of a pathogen, disease presentation, and knowledge of aviation procedures, aircraft engineering and design is of great importance in preparing for such missions. Our approach of multidiscipline team involvement managed to allow us to provide and execute the operations successfully.

Évacuation sanitaire massive de patients COVID sur vecteur aérien civil

Dans le contexte de pandémie COVID, les capacités d’hospitalisations de patients infectés à la Réunion restent limitées et imposent une réflexion sur les alternatives envisageables. Les évacuations sanitaires (EVASAN) de masse sur des vols commerciaux long-courriers pourraient être une solution intéressante. Ce type d’opération est toutefois complexe à mettre en œuvre. Une réflexion a été menée autour d’une organisation dans les avions de la compagnie Air Austral (Boeing 737, 777 et 787) permettant d’assurer les soins et les déplacements dans l’appareil en définissants des zones de basse densité virale et haute densité virale. Un modèle de prise en charge des patients a été élaboré avec une planification des moyens humains et matériels nécessaires au transfert de plusieurs patients COVID « valides » et en civière. Ce dispositif a ensuite été déployé au cours d’une EVASAN de quatre patients depuis Mayotte vers la Réunion. Les évacuations sanitaires aériennes de masse de patients infectés par le Coronavirus apparaissent comme une solution à l’engorgement des services d’hospitalisation conventionnelle et de réanimation pour les territoires ultramarins. L’expérimentation réalisée sur un vol Mayotte-Réunion s’est avérée encourageante.

Medical evacuations of members of the French armed forces for infectious diseases in foreign operations

OBJECTIVES

Medical evacuations from foreign settings are a major health and strategic problem for the armed forces. This work aimed to study the characteristics of French military evacuations due to infectious diseases.

PATIENTS AND METHODS

We performed a retrospective study based on the registers of the French operational military staff for health to assess the characteristics of the strategic medical evacuation of French armed forces members on missions abroad between January 1, 2011 and December 31, 2016.

RESULTS

Out of 4633 included cases, 301 medical evacuations (6.5%) were carried out due to infectious situations. More than half of patients were repatriated to surgical wards (162 patients, 54%), 108 patients (36%) to medical wards, 21 patients (7%) to intensive care units, six patients (2%) to an armed forces medical center, and four files (1%) were incomplete. Among infectious emergencies, malaria led to 30 evacuations (10%) including 11 to intensive care units and one death before evacuation. Infectious diseases requiring medical evacuation were most often mild and community-acquired. Most soldiers were evacuated without medical assistance.

CONCLUSIONS

Infectious diseases during missions and medical repatriations carried out for infectious reasons are important epidemiological indicators to monitor. They make it possible to adapt preventive measures, training, and diagnostic and therapeutic tools which can be made available to front-line military physicians.

Review of Literature for Air Medical Evacuation High-Level Containment Transport

INTRODUCTION

Aeromedical evacuation (AE) is a challenging process, further complicated when a patient has a highly hazardous communicable disease (HHCD). We conducted a review of the literature to evaluate the processes and procedures utilized for safe AE high-level containment transport (AE-HLCT) of patients with HHCDs.

METHODS

A literature search was performed in PubMed/MEDLINE (from 1966 through January 2019). Authors screened abstracts for inclusion criteria and full articles were reviewed if the abstract was deemed to contain information related to the aim.

RESULTS

Our search criteria yielded 14 publications and were separated based upon publication dates, with the natural break point being the beginning of the 2013-2016 Ebola virus disease epidemic. Best practices and recommendations from identified articles are subdivided into pre-flight preparations, inflight operations, and post-flight procedures.

CONCLUSIONS

Limited peer-reviewed literature exists on AE-HLCT, including important aspects related to healthcare worker fatigue, alertness, shift scheduling, and clinical care performance. This hinders the sharing of best practices to inform evacuations and equip teams for future outbreaks. Despite the successful use of different aircraft and technologies, the unique nature of the mission opens the opportunity for greater coordination and development of consensus standards for AE-HLCT operations.

Aeromedical Transfer of Patients with Viral Hemorrhagic Fever

For >40 years, the British Royal Air Force has maintained an aeromedical evacuation facility, the Deployable Air Isolator Team (DAIT), to transport patients with possible or confirmed highly infectious diseases to the United Kingdom. Since 2012, the DAIT, a joint Department of Health and Ministry of Defence asset, has successfully transferred 1 case-patient with Crimean-Congo hemorrhagic fever, 5 case-patients with Ebola virus disease, and 5 case-patients with high-risk Ebola virus exposure. Currently, no UK-published guidelines exist on how to transfer such patients. Here we describe the DAIT procedures from collection at point of illness or exposure to delivery into a dedicated specialist center. We provide illustrations of the challenges faced and, where appropriate, the enhancements made to the process over time.

Aeromedical Evacuation of Patients with Contagious Infections

Most patients with infectious diseases, including biologic warfare casualties, can be safely transported by aeromedical evacuation (AE) using standard precautions. However, certain contagious diseases (e.g., tuberculosis, pneumonic plague, viral hemorrhagic fever) require transmission-based precautions to protect the other patients, medical personnel, and aircrew. AE planning for these patients must take into account international public health regulations. Given adequate resources, foresight, and expertise, the AE of infected patients and biologic warfare casualties can be safely accomplished.

This chapter provides a review of the aeromedical evacuation of patients with communicable diseases. Topics include a review of the ecology of aircraft cabins and engineering features of aircraft ventilation systems that minimize the risk of disease transmission; examples of point source outbreaks related to air travel; in-flight preventive measures including the use of patient isolators; and US military and international policy and legal aspects of transporting patients with communicable diseases. Examples include in-flight transmission of tuberculosis, severe acute respiratory syndrome (SARS), smallpox, and measles.The chapter will also discuss experience in transporting patients with contagious diseases including viral hemorrhagic fevers and new patient isolation technologies that were used for the long-distance transport of patients with Ebola virus disease during the 2014–2016 West African epidemic.