Bats are essential to the world’s ecosystems, but they are known carriers of several viruses. Humans are increasingly encroaching on their habitat, increasing the risk of new pandemics, so scientists are studying bats for clues about how to prevent new outbreaks.
Dusk is the witching hour at the Accra Zoo. It’s time for the captive colony of straw-colored fruit bats to start stirring up and the best time for them to be tested for various pathogens.
A team of scientists from the University of Ghana Veterinary School is here to analyze bat droppings, or guano.
They are involved in an international effort to predict the next pandemic and even in the extreme heat of Ghana’s rainy season, they dress completely in personal protective equipment. They enter the enclosure and spread a white tarp on the ground.
Lead scientist Dr. Richard Suu-ire has been studying bats for many years. He explains that personal protective equipment is necessary “to protect you from any infection you catch in the cage, but also to prevent the bats from getting anything from us. So it’s protection both ways.”
Much remains a mystery about these animals – the only mammals that fly – and their extraordinary immune systems. Somehow bats can carry a lot of viruses but don’t seem to get sick themselves.
Ghana has joined countries such as Bangladesh and Australia as part of a global project called Bat OneHealth, which is exploring how pathogens are transmitted from one species to another and what can be done to prevent so-called spillover events.
In light of the Covid pandemic, the bat-borne viruses focused on in this study include coronaviruses.
Warning: This article contains a photo of dead animals that may upset some people
Dr. Suu-ire explains that they test for paramyxoviruses and coronaviruses in the bats. In humans, these viruses are more familiarly perceived as diseases such as mumps, measles, and respiratory infections.
He describes the bats as “reservoirs” because they carry the infection without getting sick themselves.
“So we want to monitor and see what’s going on.”
He says when they worked with the wild bat populations they found no Covid-19.
Today, his team also tests for superbugs in bat faeces. The scientists fed the bats papaya fruit, and once the bats defecated on the tarp, they take cotton swabs from the bright orange droppings and store them in test tubes.
The University of Ghana is at the forefront of this new field of research and this project is the first of its kind. However, there are still many gaps in scientific knowledge.
Ultimately, they try to find out if there are bacteria in bat feces that are resistant to antibiotics.
Dr. Suu-ire: “If there is resistance, we will find out which antibiotics they develop resistance to. In the future, we will try to isolate the resistance genes from these bacteria.”
This is not the only bat study at the University of Ghana.
In the undergrowth of the university’s botanic gardens, Dr. Kofi Amponsah-Mensah sets up a tall green net, almost as if ready for a nighttime game of badminton.
With these nets he can temporarily catch some bats, which he then examines, measures and eventually releases back into the wild. As an ecologist, he is concerned about how humans are increasingly encroaching on bat habitat.
He points out that deforestation rates in Ghana are high, with much mining destroying vegetation, the natural habitat of the bats.
“I think we’re just using bats as scapegoats for areas where we’ve failed as humans because we haven’t had many of these diseases historically,” he says.
‘We are the ones that invade the bats’ [habitat], you know, and messing with the ecosystem. This obviously leads to more contact and then the likelihood of some of these diseases popping up.”
Any discussion of how humans interact with bats inevitably leads to the topic of bushmeat.
A variety of animals are sold at a bushmeat market along a disused railway line in central Accra. These markets are a bottleneck where wildlife, such as bats, come into contact with humans. This creates a risk that these scientists want to avoid.
It is certainly not a place for the faint hearted. There are large rodent-like animals called grass cutters with long tails, and dead antelopes with their throats slit – signs of the different ways they were hunted in the wild.
The heat in the market is overwhelming because many of the women who work here cook on open stoves. In the corner of a stall, we see what appears to be a pan lid full of shriveled, straw-colored fruit bats. According to Dr. Amponsah-Mensah, they were seared on a fire to remove the hair.
In the wake of the Covid pandemic, some experts have called for such markets to be banned in case they help spread the viruses. Although Dr. Amponsah-Mensah says he wouldn’t choose to eat bat himself, he feels conflicted about a blanket ban.
He says the bushmeat trade is something that has existed for thousands of years and is deeply rooted in people’s cultures and histories, with many people preferring bushmeat to beef or chicken.
“The trade is mostly dominated by women and for a lot of them this is the only trade they know because it has been handed down from their grandparents to their mothers, and now they are in the trade too,” he says.
“So any attempt to ban bushmeat without really thinking about the complexities of the trade will have serious implications.”
In the sterile high-security laboratories of the Noguchi Institute for Medical Research on the campus of the University of Ghana, bat droppings from the Accra Zoo will be analyzed by associate professor of virology Kofi Bonney.
While keying a secret code into an electronic keyboard, he explains that these laboratories have negative air pressure to prevent pathogens from escaping.
Since the pandemic, Prof. Bonney and his team have been busier than ever in the global effort to anticipate future virus outbreaks.
prof. Bonney explains the growing relevance of the Bat OneHealth project: “We should have the environment working together with the animal sector and the human sector. We need to set up systems that pick up some of these viruses very early so that we can control the spread.
“Otherwise, once a virus enters the human system, it continues to circulate and there is a strong tendency for the virus to change. As they change, they can develop the ability to become a more serious disease. So the best thing is for us to develop systems that they can pick up early.”
Experts worry that the frequency of zoonotic spillovers will increase with climate change. Humans and animals will be forced to interact more and more closely as they both compete for resources such as water and even shade from the sun.
Bats are already the focus of billions of dollars of research – in part because of their unusual immune systems, but also because they can fly such long distances. Understanding them better, as they are trying to do in Ghana, will be crucial to the health of the planet.