Bat Coronaviruses

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Coronaviruses have been in the news a lot recently due to the on-going Covid-19 pandemic, which is caused by a coronavirus, SARS-CoV-2. 

​But there are many, many different types of coronaviruses that can be found in different animals, from cats and dogs to whales and dolphins.
There are four main types of coronaviruses - alpha- , beta-, gamma-, and deltacoronaviruses. Alpha- and betacoronaviruses have their evolutionary origin in bats. Gamma and deltacoronaviruses originated in birds.​
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While we've learned a lot about coronaviruses in bats over the past 15 years, there is still a lot more to find out. So we looked for coronaviruses in fecal (poop) samples from eight different species of bat in Eswatini (Swaziland), southern Africa.
We detected coronaviruses in 8/44 (18%) of bats we screened. The percent of bats with coronaviruses varied between the different families (types) of bats: 
For most of the bats, we only detected bits and pieces of coronavirus RNA but we got full or almost full alphacoronavirus genomes from 3 little free-tailed bats (Chaerephon pumilus) and banana bats (Afronycteris nana).  These are newly-described coronaviruses and 75 - 85% similar to other known bat coronaviruses.
None of the coronaviruses we detected appear to be dangerous or harmful to people, other animals or even the bats.

We did not detect any coronaviruses from the Mauritian tomb bat (Taphozous mauritianus), the eastern greenish yellow bat (Scotophilus viridis), or the Midas free-tailed bat (Mops midas​), although we only tested a few bats from each of these species.

There is still a lot left to learn about bat coronaviruses around the world!

Setting the Terms for Zoonotic Diseases:
How the Language We Use Impacts Research, Conservation, and Public Policy

The Covid-19 pandemic has been devastating for people and communities around the world. It has also negatively impacted bat conservation:
This is partially due to the way we talk about SARS-CoV-2 (the virus that causes Covid-19) and its relationship to bat coronaviruses.
Click through the slide show below to see an example:
This problem is driven by miscommunication. Communication involves a signaller, who does the communication, and a receiver, who is the audience.
Sometimes miscommunication occurs because the signaller makes an error. But even if the signaller uses a word or phrase correctly, it can still be misunderstood or misinterpreted by the receiver. In some cases, both the signaller and receiver might be making a mistake:
Here are some examples of terms that are frequently misused or misunderstood. Each number corresponds to one of the types of miscommunication in the diagram above.

So, what can we do?

This problem of miscommunication, and the solutions, go beyond bats, and are applicable to other species, and even other issues.

Be careful with the words we use.
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The bats will thank you!

Modeling Ebola

Ebola virus disease has caused devastating outbreaks. Ebola viruses have been detected in bats, although the true reservoir is still unknown. Due to an increasing number of outbreaks in recent years, some have hypothesized that human disturbance, land-use change, or increased human population density might cause outbreaks. The potential of bat distributions has been largely unexplored.
​You can see what we found below: 

To better understand why Ebola virus disease outbreaks occur where they do, we used two types of ecological models to compare the diversity of all bats species, the diversity of each family of bats, human population density, road density, and the amount of crops and pastures at locations where Ebola viruses have spilled over to random locations in sub-Saharan Africa where Ebola virus has not spilled over. You can see the distribution of these variables below:
According to both models, we saw that Ebola virus disease was associated with areas of high bat diversity and in particular areas with high diversity of Nycterid bats:
Here you can compare the distribution of species richness for all bat species and species belonging to the Nycterid family:
We also found that Ebola disease spillover occurs where pasture cover is low. We did not see any effect of human population density, road density, or crop cover.

Why Nycterid bats?

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  • So far, Ebola has NOT been detected in Nycterids
  • BUT very few Nycterid species have been screened
  • Nycterids are occasionally consumed
  • They may roost in buildings or caves that people enter
  • They may roost with or near other animals that could be hosts
  • Maybe Nycterid diversity correlates with some other variable that we haven’t measured but explains Ebola outbreaks.
But don't forget - bats are essential parts of their ecosystems and provide important ecosystem services that benefit people - such as controlling insect populations, dispersing seeds, or pollinating plants.
There is no reason to be afraid of bats! Please respect bats as wild animals and not approach or touch them.

Leishmania and Leishmaniasis in Bats

Leishmaniasis is a disease caused by parasites in the genus Leishmania, which are transmitted to people via sandflies that may cause organ failure or disfiguring damage to skin and cartilage.
While in Brazil as a Fulbright grantee at the Federal University of Mato Grosso do Sul, we caught bats that had lesions and suspected infection with Leishmania​: 
We tested a total of five bats for Leishmania using using PCR and PCR-RFLP.
We detected Leishmania (Viannia) braziliensis in two bats - one Glossophoga soricina with lesions and positive liver tissue (possibly indicating visceral leishmaniasis) and Molossus molossus showing no lesions or symptoms.