Mass extinctions, biodiversity and mitochondrial function: are bats ‘special’ as reservoirs for emerging viruses?

Abstract

For the past 10-15 years, bats have attracted growing attention as reservoirs of emerging zoonotic viruses. This has been due to a combination of factors including the emergence of highly virulent zoonotic pathogens, such as Hendra, Nipah, SARS and Ebola viruses, and the high rate of detection of a large number of previously unknown viral sequences in bat specimens. As bats have ancient evolutionary origins and are the only flying mammals, it has been hypothesized that some of their unique biological features may have made them especially suitable hosts for different viruses. So the question 'Are bats different, special or exceptional?' has become a focal point in the field of virology, bat biology and virus-host co-evolution. In this brief review, we examine the topic in a relatively unconventional way, that is, our discussion will be based on both scientific discoveries and theoretical predictions. This approach was chosen partially because the data in this field are so limited that it is impossible to conduct a useful review based on published results only and also because we believe it is important to provoke original, speculative or even controversial ideas or theories in this important field of research.

Novel bat adenoviruses with an extremely large E3 gene

“…Previous investigations of novel bat viruses have mainly focused on RNA viruses due to the several known highly lethal RNA viral diseases that originate from bats (Chua et al, 2000;Ge et al, 2013;Leroy et al, 2005;Li et al, 2005;Wang et al, 2011). Thus, DNA viruses infecting bats remain largely unexplored.…”

“…To date, approximately 70 HAdV types have been identified and classified into seven species, Human mastadenovirus A to G (HAdV-A to HAdV-G). Recently, great attention has been paid to bats given their role as reservoirs of emerging viruses, including SARS coronavirus, Ebolavirus, Hendra virus and Nipah virus (Chua et al, 2000;Corman et al, 2015;Ge et al, 2013;Leroy et al, 2005;Li et al, 2005;Wang et al, 2011). However, most bat viruses reported are RNA viruses and were identified by nucleic acid detection.…”

Isolation of multiple novel paramyxoviruses from pteropid bat urine

“…As more zoonotic viruses are linked to bats, identifying novel agents harboured by bats has become increasingly important (Baker et al, 2012(Baker et al, , 2013bLau et al, 2010;Wang et al, 2011). Detection of viral nucleic acid by PCR to identify viruses in bats represents the most common method employed in published studies.…”

Bat Biology, Genomes, and the Bat1K Project: To Generate Chromosome-Level Genomes for All Living Bat Species

“…Without bats, it is estimated that the United States would spend more than $3 billion a year on pesticides alone (10). Bats are suspected reservoirs for some of the deadliest viral diseases [e.g., Ebola, SARS (severe acute respiratory syndrome), rabies, and MERS (Middle East respiratory syndrome coronavirus); [11][12][13][14], but they appear to be asymptomatic and survive these infections. This suggests that bats have evolved unique immune systems, and potentially the solution to better tolerate these pathogens may lie in uncovering how bats limit their immunopathology upon infection (15,16).…”

“…Only 19 mammal species live proportionately longer than humans given their body size, and 18 are bats (17), with Brandt's bat (Myotis brandtii ) holding the reported record for bat longevity [>41 years, ∼7 g (18)]. Bats show few signs of senescence and low to negligible rates of cancer (11), suggesting they have also evolved unique mechanisms to extend their health spans, rendering them excellent models to study extended mammalian longevity and ageing (17). Bats face a variety of global threats that threaten populations with regional or global extinction.…”