Field in Focus is a video series that brings you into the field with Smithsonian scientists working to save species around the globe.
Thousands of bats take to the sky as dusk settles over Linno Cave in Myanmar’s Hpa An region, and each evening a crowd of tourists gathers to witness their flight.
Around the world, similar destinations attract visitors with opportunities to interact with wildlife. But some animals carry diseases that can spread to humans, such as influenza, Ebola and SARS.
Today, three-quarters of new infectious diseases originate in animals, and human activities — from travel to farming and urbanization — contribute to the spread of these viruses. So as experts collaborate to pinpoint where and when the next global health crisis might occur, they focus on areas where people come in contact with animals.
The Smithsonian Conservation Biology Institute’s Global Health Program is an integral part of this effort, working directly with experts from three Myanmar government ministries to lead USAID's PREDICT program activities in Myanmar. PREDICT aims to detect and discover zoonotic diseases (those spread between animals and humans) using a One Health approach, which recognizes the connection between human, animal and environmental health.
Smithsonian researchers partner with experts in Myanmar studying human and animal health to find out what diseases are present in wildlife and whether they could pose a threat to humans. For the first time, see these scientists in the field as they collect blood from cave nectar bats, sample saliva from macaques and track the movement of flying foxes across the country.
Myanmar is a biodiversity hotspot with vast rural settings and forests. That habitat supports a large number of species, including bats and other animals that, in other parts of the world, have been known to carry zoonotic and emerging viruses. The country is also becoming more developed, which leads to more high-risk interactions between humans and wildlife.
Global Health Program researchers work closely with resident scientists — and collaborate with Myanmar's Ministry of Agriculture, Livestock and Irrigation; Ministry of Health and Sports; and Ministry of Natural Resources and Environmental Conservation — to collect and analyze biological samples from wildlife and the humans they come in contact with.
The researchers also investigate domestic animals and coordinate with local healthcare professionals to identify viral risks in humans. PREDICT focuses on high-risk interfaces, or areas where interactions with animals might predispose humans to disease contraction. Understanding which diseases have the capacity to jump species and where that transmission is most likely to occur could lead to earlier detection and potentially life-saving intervention.
Meet Some of the Scientists
Following a One Health approach — which combines human and veterinary medicine to solve some of the world’s larger health and conservation problems — Myanmar’s PREDICT activities are co-led by Drs. Ohnmar Aung and Marc Valitutto.
The Bats of Linno Cave
More than 500,000 bats roost in Linno Cave, crossing paths with people and livestock every day. The team conducts most of their work at night when the bats emerge from the caves to feed. Working carefully, the researchers collect measurements and samples from each animal they catch.
Linno Cave is home to at least four bat species. So far, the researchers have successfully caught and taken samples from wrinkle-lipped bats and cave nectar bats. The bats are given sugar water before being released to ensure they have the energy to continue their flight — just like a person might receive a sugary juice after a blood drive.
Myanmar scientists at collaborating government laboratories in Yangon analyze the samples from each research site for four viral families:
Examples: Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS)
These viruses are common in many species, including camels and bats. Though most coronaviruses are species-specific, some have spread to humans.
In primates, including humans, filoviruses can cause hemorrhagic fever — which damages the vascular system and impacts the body's ability to regulate itself. This viral family has also been detected in pigs and bats. Bats are believed to be the source of recent Ebola outbreaks in Africa.
Examples: Nipah virus, Hendra virus, Measles, Mumps, Canine distemper
The flying fox is a natural carrier for both Hendra virus and Nipah Virus. Hendra can cause respiratory and neurologic diseases in horses and humans, while Nipah has spread to pigs and humans, causing encephalitis (inflammation of the brain) and respiratory illness.
- Influenza viruses
Examples: Bird flu (e.g., H5N1, H7N9), Swine flu (e.g., H1N1)
Influenza viruses impact many species, including (but not limited to) ducks, chickens, pigs, whales, horses, seals and humans. The flu can spread from person to person, and is most common in the U.S. during the fall and winter.
Scientists sequence the viruses they detect in animals to determine their pathogenicity, or ability to cause disease, in humans. Any viruses detected in samples from animals or humans are also analyzed for pandemic potential. If a virus is considered a concern, the researchers work with Myanmar’s government to determine the immediacy of the issue and whether a response is necessary.
The researchers have already identified two new coronaviruses in saliva and fecal samples from insect-eating bats. One of these viruses had never been detected in the world, and the second had only been identified in Thailand’s bats. While these new viruses belong to the same family as SARS and MERS, there is no evidence that they pose a threat to people at this time.
The Monkeys of Kawgun Cave
Kawgun Cave, another research site in Hpa An, draws locals and travelers for its historic, religious and cultural significance. Groups of macaques congregate just outside the cave where visitors often feed them by hand. The team uses a unique method to collect DNA samples from these monkeys.
Sample collection can be challenging, and weather complications can damper the work. PREDICT guidelines require full personal protective equipment, which can be especially cumbersome in intense heat and rain.
At times, it may also be difficult to ask local participants to wear the protective equipment when they have long interacted with these animals without it. Ultimately, the team’s goal is to put as little stress as possible on their partners in the field, the local community members they interact with and the animals they sample.
LOOK INSIDE: Take a Virtual Tour of the Caves
The Animals of Hlawga National Park
At Hlawga National Park in Myanmar’s Yangon region, tourists mingle with animals, including sambar deer, Asian elephants, macaques, wild boars, pigs, bats and rodents — some of which are endangered. See what scientists look for and how they gauge the threat of zoonotic diseases to protect both people and animals.
In addition to concerns about viruses spilling over to humans, researchers are also interested in what diseases may spread among the different animals that live in the park.
The more samples the team collects, the better chance they have of detecting a virus and assessing which species carry certain diseases. At every research site, they collect about 10-12 samples from at least 300 individuals per species, including humans.
Wildlife veterinarians are also interested in how an animal’s movement from place to place can inform infectious-disease research. Paired with biological samples, such as blood, feces and saliva, movement data can give them a sense of how diseases also travel within an environment.
Tracking Flying Foxes
With help from experts at the Smithsonian’s Movement of Life initiative, the GHP team is tracking Indian flying foxes. Also called megabats, flying foxes are some of the largest bats in the world. They provide vital ecosystem services, spreading seeds and pollinating as they travel from tree to tree feeding on fruit. But they are also associated with dangerous diseases, including rabies, influenza, Nipah virus and Hendra virus.
To track flying foxes, researchers designed a special GPS collar that is lightweight, easily fastened and accounts for the bats’ unique physiology (like flying horizontally and roosting upside down).
The team has already discovered where the bats go to feed. Now, they are gathering site-specific information, such as what types of trees are present, if the area is forest or farmland, and if other animals or people live nearby.
The health of humans, animals and the environment is inextricably linked. A better understanding of the bats’ movement will help inform future conservation strategies that protect both the bats and the people they come into contact with.
What Comes Next?
As the Global Health Team enters their fifth and final year of the PREDICT project, they are sharing data with local communities and making recommendations to reduce risk. Through education and collaboration, they hope that the people of Myanmar will have the resources and desire to continue investigating disease surveillance and prevention long after the Smithsonian team leaves.
The Myanmar government has been a critical partner throughout the project, working directly with the Smithsonian team to conduct field surveillance, train scientists and analyze samples in-country. And more than 500 individuals have already received hands-on training in biosecurity, temperature-controlled supply chain management, personal protective equipment, laboratory analysis, and the safe handling and sampling of various animals since the project began.
This work was funded by USAID PREDICT and, in part, by the Smithsonian's Women's Committee, and the Judy and John McCarter, Jr. Global Health internship. This project is a collaboration with three of Myanmar's government ministries: the Ministry of Agriculture, Livestock and Irrigation (MOALI); the Ministry of Health and Sports (MOHS); and the Ministry of Natural Resources and Environmental Conservation (MONREC).
It would not be possible without the following collaborators in Myanmar: Department of Medical Research, MOHS; the Livestock, Breeding, and Veterinary Department (LBVD), MOALI; Forestry Department, MONREC; State Health Department, Kayin; Regional Health Department, Yangon; Township Health Department, Hpa-an; Township Health Department, Hmawbi, Taikkyi; LBVD, Kayin State; LBVD, Yangon Region; Forestry Department, Kayin State; Officials from Hlawga National Park, Yangon; Township Administrative Department, Hpa-an; Township Administrative Department, Yangon; and respected community members and volunteers in Hpa-an, Hmawbi and Taikkyi.