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The emergence of mobile mcr genes mediating resistance to colistin is a critical public health issue that has hindered the treatment of serious infections caused by multidrug‐resistant pathogens in humans and other animals. We report the emergence of the mcr‐9.1 gene in a polymyxin‐resistant extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacter kobei infecting a free‐living franciscana dolphin (Pontoporia blainvillei), threatened with extinction in South America. Genomic analysis confirmed the presence of genes conferring resistance to clinically relevant β‐lactam [blaCTX‐M‐15, blaACT‐9, blaOXA‐1 and blaTEM‐1B], aminoglycoside [aac(3)‐IIa, aadA1, aph(3'')‐Ib and aph(6)‐Id], trimethoprim [dfrA14], tetracycline [tetA], quinolone [aac(6')‐Ib‐cr and qnrB1], fosfomycin [fosA], sulphonamide [sul2] and phenicol [catA1 and catB3] antibiotics. The identification of mcr‐9.1 in a CTX‐M‐15‐producing pathogen infecting a critically endangered animal is of serious concern, which should be interpreted as a sign of further spread of critical priority pathogens and their resistance genes in threatened ecosystems. [ABSTRACT FROM AUTHOR]

The humpback whale (HW; Megaptera novaeangliae) population that seasonally resides along the Brazilian coast concentrates in the Abrolhos Bank (Bahia and Espírito Santo states) for breeding during austral winter and spring. Cetacean morbillivirus (CeMV, Paramyxoviridae family) is currently one of the most significant biological threats to cetaceans worldwide with high infection and mortality rates. CeMV is pleiotropic yet it has special tropism for the respiratory, lymphoid and nervous system and is primarily transmitted by the aerogenous route. A new lineage of CeMV, the Guiana dolphin morbillivirus (GDMV), is known to affect cetaceans off Brazil. GDMV was first detected in a Guiana dolphin (Sotalia guianensis) stranded in the Abrolhos Bank region, in 2010. In addition to pathologic examinations on stranded HW, pathogen survey of free‐ranging HW may provide valuable insight into the epidemiology of diseases. We hypothesized that HW in the Brazilian breeding ground could be exposed to CeMV. Thus, in the present study, we investigated the presence of CeMV in exhaled breath condensates (EBC) of HW in the Abrolhos Bank. Overall, 73 samples of EBC from 48 groups of HW were collected during the breeding seasons of 2011 (n = 16) and 2012 (n = 57). One sample failed to have the reference gene amplified and was excluded from the study. CeMV was detected by a RT‐qPCR method in 2 EBC samples, representing 2 whale groups. Phylogenetic analysis of partial morbillivirus phosphoprotein gene showed 100% homology to GDMV. Our results show that HW in Brazil are infected by CeMV with a relative prevalence of 4.3% (2/47) and demonstrate the suitability of using EBC and RT‐qPCR as a non‐invasive tool for CeMV survey in free‐ranging whales. This pioneer study provides scientific basis for non‐invasive CeMV monitoring of HW, suggests HW may play a role in the dynamics of CeMV and raises concern for potential conservation implications for this species. [ABSTRACT FROM AUTHOR]

Summary: Cetacean morbillivirus (CeMV) has caused repeated epizootics and interepizootic fatalities in a variety of cetacean species worldwide. Recently, a novel CeMV strain (GD‐CeMV) was linked to a mass die‐off of Guiana dolphins (Sotalia guianensis) in Brazil. Southern right whales (SRWs; Eubalaena australis) migrate to the southern Brazilian coast during austral winter and spring (June through November) for breeding and calving. Because unexplained high calf mortality rates have recurrently been documented in SRWs, we hypothesized they could be infected with CeMV. We developed a novel real‐time RT‐PCR method based on SYBR®GREEN for detection of CeMV and identified the virus in three out of five stranded SRWs from Santa Catarina state, Brazil. The partial sequences of the morbillivirus phosphoprotein gene suggest that the virus is similar to the GD‐CeMV strain. Our results indicate CeMV can infect SRWs and should be considered in the differential aetiologic diagnosis of infectious diseases in this species. It also raises concern for potential conservation implications for this species in its main coastal breeding area off Southern Brazil. [ABSTRACT FROM AUTHOR]