Highly diverse morbillivirus-related paramyxoviruses in wild fauna of the southwestern Indian Ocean Islands: evidence of exchange between introduced and endemic small mammals.
The Paramyxoviridae form an increasingly diverse viral family, infecting a wide variety of different hosts. In recent years, they have been linked to disease emergence in many different animal populations and in humans. Bats and rodents have been identified as major animal populations capable of harboring paramyxoviruses, and host shifting between these animals is likely to be an important driving factor in the underlying evolutionary processes that eventually lead to disease emergence. Here, we have studied paramyxovirus circulation within populations of endemic and introduced wild small mammals of the southwestern Indian Ocean region and belonging to four taxonomic orders: Rodentia, Afrosoricida, Soricomorpha, and Chiroptera. We report elevated infection levels as well as widespread paramyxovirus dispersal and frequent host exchange of a newly emerging genus of the Paramyxoviridae, currently referred to as the unclassified morbillivirus-related viruses (UMRVs). In contrast to other genera of the Paramyxoviridae, where bats have been shown to be a key host species, we show that rodents (and, in particular, Rattus rattus) are significant spreaders of UMRVs. We predict that the ecological particularities of the southwestern Indian Ocean, where small mammal species often live in densely packed, multispecies communities, in combination with the increasing invasion of R. rattus and perturbations of endemic animal communities by active anthropological development, will have a major influence on the dynamics of UMRV infection.


OBJECTIVE
Identification of the infectious agents that circulate within wild animal reservoirs is essential for several reasons: (i) infectious disease outbreaks often originate from wild fauna; (ii) anthropological expansion increases the risk of contact between human and animal populations and, as a result, the risk of disease emergence; (iii) evaluation of pathogen reservoirs helps in elaborating preventive measures to limit the risk of disease emergence. Many paramyxoviruses for which bats and rodents serve as major reservoirs have demonstrated their potential to cause disease in humans and animals. In the context of the biodiversity hot spot of southwestern Indian Ocean islands and their rich endemic fauna, we show that highly diverse UMRVs exchange between various endemic animal species, and their dissemination likely is facilitated by the introduced Rattus rattus. Hence, many members of the Paramyxoviridae appear well adapted for the study of the viral phylodynamics that may be associated with disease emergence.
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Université de La Réunion, La Réunion, France dwilkin799@gmail.com herve.pascalis@ird.fr.
David A
DA
Wilkinson
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Université de La Réunion, La Réunion, France.
Julien
J
Mélade
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Université de La Réunion, La Réunion, France.
Muriel
M
Dietrich
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Association Vahatra, Antananarivo, Madagascar.
Beza
B
Ramasindrazana
Association Vahatra, Antananarivo, Madagascar.
Voahangy
V
Soarimalala
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Institut de Recherche pour le Développement (IRD), IRD-BP 50172, La Réunion, France.
Erwan
E
Lagadec
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Institut de Recherche pour le Développement (IRD), IRD-BP 50172, La Réunion, France.
Gildas
G
le Minter
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Université de La Réunion, La Réunion, France.
Pablo
P
Tortosa
Virology Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
Jean-Michel
JM
Heraud
UMR_D 190, Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, Marseille, France.
Xavier
X
de Lamballerie
Association Vahatra, Antananarivo, Madagascar Field Museum of Natural History, Chicago, Illinois, USA.
Steven M
SM
Goodman
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Institut de Recherche pour le Développement (IRD), IRD-BP 50172, La Réunion, France.
Koussay
K
Dellagi
Centre de Recherche et de Veille sur les Maladies Émergentes Dans l'Océan Indien (CRVOI), Plateforme de Recherche CYROI, La Réunion, France Institut de Recherche pour le Développement (IRD), IRD-BP 50172, La Réunion, France dwilkin799@gmail.com herve.pascalis@ird.fr.
Herve
H
Pascalis
D000818:Animals; D000835:Animals, Wild; D016000:Cluster Analysis; D014644:Genetic Variation; D007195:Indian Ocean Islands / Q000453:epidemiology; D008969:Molecular Sequence Data; D010252:Paramyxoviridae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D018184:Paramyxoviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology
D012367:RNA, Viral