What is the fine-grained topic of the following text: Evolutionary analysis and phylogenetic inferences indicated that the Brazilian BRTO-83 Cosavirus strain was a recombinant virus highly related to the E/D recombinant NG385 strain (Genbank JN867757), which was isolated in Nigeria from an acute flaccid paralysis patient. Only return the topic.
Evolutionary Analysis of Brazilian BRTO-83 Cosavirus Strain