In the hot zone

Public health veterinarians help rein in West African Ebola outbreak
Published on
information-circle This article is more than 3 years old

Veterinarians are among the small army of public health workers fighting in West Africa against an epidemic that has so far killed more than 10,000 people and which the World Health Organization has described as “the most severe, acute public health emergency seen in modern times.”

The ongoing Ebola virus outbreak in West Africa is the largest in history, with more cases since March 2014 than in all previous Ebola outbreaks combined. The virus even spread as far as the United States via an infected Liberian national, who passed the virus to a nurse at the Texas hospital where he was treated. As of press time in April, the relatively low number of new Ebola virus disease cases being reported suggests the worst of the outbreak is over.

Many veterinarians are helping to alleviate the current outbreak. Following are the accounts of three U.S. veterinarians who participated in the international response in the hardest-hit countries of Liberia, Sierra Leone, and Guinea.

The Epidemiologist

Since early in the Ebola virus disease epidemic, Dr. James Zingeser had helped coordinate the emergency response in Liberia, Guinea, and Sierra Leone for the Food and Agriculture Organization of the United Nations. An epidemiologist on loan from the U.S. Centers for Disease Control and Prevention, Dr. Zingeser had no experience with Ebola. But he spoke French, had years of experience in West Africa, and was assured by the head of the CDC’s Viral Special Pathogens Branch he was up to the task.

Dr. Zingeser spent part of April and May 2014 in Guinea, first in Gueckedou and then in the capital of Conakry along the Atlantic coast. Located in the southern part of the country near the Liberian and Sierra Leonean borders, Gueckedou was the epicenter of the Ebola epidemic. When he arrived in the town, Dr. Zingeser quickly recognized the epidemic was unlike previous outbreaks he had seen.

“It was obvious we were dealing with a complex emergency, something that was going to affect the whole of Guinean society,” he said.

Map: Guinea, Sierra Leone, and Liberia

From the beginning, some communities resisted cooperating with the teams of medical personnel from the Guinea Ministry of Health, World Health Organization, CDC, Red Cross, and Doctors Without Borders to contain the virus. Complicating matters were the negative impacts of the control strategies. “Government authorities stopped people from gathering in groups and closed markets. Farmers were afraid to go to their fields for fear of coming into contact with infected animals. These measures were harming food security and rural livelihoods,” Dr. Zingeser said.

As evidenced by the past year, containing an Ebola epidemic within an impoverished country where public health resources are scarce requires an almost unprecedented response from the global community, according to Dr. Zingeser. For instance, Guinea’s health care infrastructure is fragmented, underfunded, and understaffed, and much of the rural population has little or no contact with the formal medical community.

In African nations including Sudan, Uganda, and the Democratic Republic of Congo—where Ebola cases have sporadically occurred since the virus was identified in 1976—it is generally understood that the pathogen is passed through body fluids and close contact, so practices such as burial rituals are temporarily suspended to prevent infection. One explanation for why the current outbreak spread so far in the crucial first three months is that, until 2014, the Ebola virus was unknown in West Africa. Lacking even a basic knowledge of the disease presentation and epidemiology, authorities did not implement basic control measures quickly enough.

Then, there’s what Dr. Zingeser calls “Ebola panic disease.” Something about hemorrhagic fevers incites a deep psychological reaction in people, provoking them to act irrationally, he observed. “During the first two weeks I was in Gueckedou, rumors spread that Ebola was brought in by foreign health workers, and we had people with machetes and rocks attacking our vehicles. Once that fear sets in, the challenges transcend the medical response,” he said.

During the first two weeks I was in Gueckedou, rumors spread that Ebola was brought in by foreign health workers, and we had people with machetes and rocks attacking our vehicles. Once that fear sets in, the challenges transcend the medical response.

Dr. James Zingeser, one of the coordinators of emergency response in Liberia, Guinea, and Sierra Leone for the United Nations Food and Agriculture Organization

Such fear and aggression, Dr. Zingeser explained, were, in part, a consequence of the responders’ failure to communicate in a culturally appropriate manner. “In the beginning of this epidemic, public health messages assumed that people would trust in the biomedical model. It implied a ‘We’re right, and you’re wrong,’ point of view that got us nowhere,” he said.

Whereas Guinean farmers may have little contact with the formal medical community, they are likely to know either an agricultural extension officer or a representative of the nation’s Veterinary Services. Dr. Zingeser said these government officials deliver fertilizer and seed to rural communities and talk to farmers about the health of their livestock. “These officers are able to access rural communities in a way the medical authorities couldn’t,” he said.

In May 2014, the UN FAO country director and Dr. Zingeser convened a meeting of Veterinary Services and the Ministry of Health in the capital of Conakry to discuss using agriculture agents to educate communities about preventing Ebola and to identify and trace individuals who had contact with persons infected with the Ebola virus. Plans were made for Veterinary Services, once the epidemic abates, to investigate the animal reservoirs of the Ebola virus in Guinea and explore factors that may have caused the virus to spill over to humans.

When Dr. Zingeser spent two months in Sierra Leone late last year, he again took advantage of the unique access veterinarians and agriculture officers have in rural communities. “We had UNICEF train livestock agents to deliver basic messages about Ebola and how to prevent it,” he said. In December, these agents were brought together by FAO in Sierra Leone to discuss their successes and challenges, and there was general enthusiasm and pride in their accomplishments. “It was clear that veterinarians and agriculture agents can make an important contribution to responding to complex emergencies, in a whole-of-society response,” he said.

A cemetery holding Ebola victims in the Bombali District of Sierra Leone (Courtesy of Josta Hopps)

The Captain

Dr. Leigh Sawyer is a captain with the U.S. Public Health Service. She had several years of experience working with HIV in a biosafety level 3 laboratory before traveling in December 2014 to Margibi County in Liberia to oversee the clinical laboratory at the Monrovia Medical Unit, a 25-bed field hospital reconfigured to treat Ebola patients.

A Liberian health care worker cured of Ebola leaves her handprint on the Survivor Wall outside the Monrovia Medical Unit. (Courtesy of Dr. Leigh Sawyer)

Part of the Department of Health and Human Services, the USPHS Commissioned Corps comprises over 6,500 uniformed public health professionals, including veterinarians, who deploy in times of public health emergencies, both foreign and domestic. One of three USPHS veterinarians stationed at the same time at the MMU, Dr. Sawyer said veterinarians are an essential component in the response to public health crises such as the Ebola outbreak.

“Veterinarians have a working knowledge and appreciation of the ecology and epidemiology of infectious diseases and the expectation that there is a link between human and animal diseases,” she said. “We study animals in their ecosystem and appreciate the relationships that impact health and disease.”

From November 2014 to February 2015, the Monrovia Medical Unit cared for 35 health care workers, 17 of whom tested positive for the Ebola virus, according to Dr. Sawyer. Eight of the infected patients had recovered and were discharged from the hospital by the time she left Liberia on Feb. 8. “This is a positive sign for other brave health care workers on the front lines, that there are resources for them if they become ill with Ebola,” Dr. Sawyer said.

Boris Lushniak, MD, deputy surgeon general of the U.S. Public Health Service (left), with USPHS veterinarians Drs. Amy Peterson, Leigh Sawyer, and Evan Shukan in front of the medical unit in Monrovia, Liberia

Each patient admission was an intense and highly choreographed process in which every step was predetermined, from who was performing which task to the supplies needed, Dr. Sawyer recalled. Prior to entering the high-risk zone—that is, where Ebola-infected patients were being treated, hospital personnel would don full personal protective equipment that included knee-high rubber boots, two pair of gloves, a full-body protective suit, waterproof apron, hood, face mask or goggles, and respirator. The donning process was a team effort, and prior to entry, all officers were checked and rechecked to ensure proper wear and that there were no rips in the PPE.

Dr. Leigh Sawyer, dressed from head to toe in protective gear, enters data in the laboratory of the Monrovia Medical Unit in Liberia (Photos courtesy of Dr. Leigh Sawyer)

Dr. Sawyer’s laboratory team followed behind the patient-receiving team to process blood samples. They transported the blood to be tested for Ebola virus and malaria parasites to laboratories staffed by the U.S. Department of Defense and HHS. Clinical chemistries, hemoglobin, hematocrit, and coagulation factors were among the battery of in-house tests performed by her team, who logged some of the highest number of hours in the high-risk zone. The names of staff and the time each spent in the zone were recorded on white boards.

“When we arrived, the Monrovia Medical Unit was already considered to be the best-equipped treatment center in West Africa,” Dr. Sawyer said. Her team increased the capabilities in the unit’s laboratory to include rapid diagnostic testing for malaria and HIV as well as a blood transfusion service.

“My goal was to provide the medical team with the best possible laboratory tests and results on which to base their medical care as well as access to potentially lifesaving transfusions,” she added.

The Veteran

Dr. Thomas Ksiazek is a world-renowned specialist in filoviruses with nearly 40 years’ experience on the front lines of infectious disease research.

By the time I arrived, there was already in Liberia a circumstance in Monrovia that was beyond comprehension. The virus at that point was basically out of control, and part of our job was to make sure it didn’t get that way in Sierra Leone.

Dr. Thomas Ksiazek, a specialist in filoviruses who recently led the Centers for Disease Control and Prevention’s Ebola outbreak control operations in Sierra Leone

As the former chief of the Special Pathogens Branch at the CDC, Dr. Ksiazek had coordinated outbreak and control responses to Ebola, Marburg, and sudden acute respiratory syndrome viruses; he helped identify SARS. In August 2014, Dr. Ksiazek took a six-week sabbatical from the University of Texas Medical Branch, where he manages high-containment laboratory operations for the Galveston National Laboratory, to lead the CDC’s Ebola outbreak control operations in Sierra Leone until late September.

Agricultural extension agents meet in December 2014 in Makeni, Sierra Leone, to plan a health education campaign to stop Ebola virus transmission. (Courtesy of Josta Hopps)

Working with health officials in the capital of Freetown, the CDC team found that the epidemiologic data were incomplete and inconsistent. “For instance, about 35 percent of the case reports did not record whether the patient lived or died,” Dr. Ksiazek recalled.

Complicating matters, the outbreak began to expand into other areas from its initial epicenter, and the already sizable Ebola caseload exploded.

“Cases were now beginning to occur in Freetown, which was a scary proposition because by the time I arrived, there was already in Liberia a circumstance in Monrovia that was beyond comprehension,” he said. “The virus at that point was basically out of control, and part of our job was to make sure it didn’t get that way in Sierra Leone.”

Before he left Sierra Leone, his team had deployed a standardized case investigation form and connected local data collection sites into a national database, allowing analysis of the epidemiologic data on a national level.

A health care worker in Macenta, Guinea, ensures that people wash their hands with a chlorine solution before entering the health center. (Courtesy of Dr. James Zingeser)

Ebola virus is a manageable pathogen, Dr. Ksiazek explained, so long as control measures are implemented quickly, when the first cases are reported. That didn’t happen in West Africa. He said, “Control is really dependent on a very simple set of principles: Find all the cases, isolate them in treatment facilities, locate all the contacts of the known cases, and follow them closely because they’re the next potential generation of the disease.

“If you do that rigorously, you can pretty quickly control the outbreak. But it depends on an early response, when the problem isn’t so large. That’s what’s so significant about this West Africa outbreak: It surpassed the capability on the ground to effectively apply the principles that have allowed us to control transmission in previous settings.”

Related JAVMA content:

Once ‘over there,’ Ebola now here (Dec. 1, 2014)

Viral Threats (May 15, 2014)

Viruses found in confiscated primate meat (July 1, 2012)