The pathogen transmission dynamics in bat reservoirs underpin efforts to reduce risks to human health and enhance bat conservation, but are notoriously challenging to resolve. For vampire bat rabies, the geographical scale of enzootic cycles, whether environmental factors modulate baseline risk, and how within-host processes affect population-level dynamics remain unresolved. We studied patterns of rabies exposure using an 11-year, spatially replicated sero-survey of 3709 Peruvian vampire bats and co-occurring outbreaks in livestock. Seroprevalence was correlated among nearby sites but fluctuated asynchronously at larger distances. A generalized additive mixed model confirmed spatially compartmentalized transmission cycles, but no effects of bat demography or environmental context on seroprevalence. Among 427 recaptured bats, we observed long-term survival following rabies exposure and antibody waning, supporting hypotheses that immunological mechanisms influence viral maintenance. Finally, seroprevalence in bats was only weakly correlated with outbreaks in livestock, reinforcing the challenge of spillover prediction even with extensive data. Together our results suggest that rabies maintenance requires transmission among multiple, nearby bat colonies which may be facilitated by waning of protective immunity. However, the likelihood of incursions and dynamics of transmission within bat colonies appear largely independent of bat ecology. The implications of these results for spillover anticipation and controlling transmission at the source are discussed.

The extensive use of antibiotics is a leading cause for the emergence and spread of antimicrobial resistance (AMR) among dogs. However, the impact of using antibiotics to treat viral infections on AMR remains unknown. In this study, we compared the prevalence of extended-spectrum cephalosporin-resistant Enterobacterales (ESCR-E) between dogs with a suspected infection of canine parvovirus (CPV) and canine distemper (CDV) before and after treatment with third-generation cephalosporins. We found a higher prevalence of ESCR-E faecal carriage in dogs suspected of CPV (37%) and CDV (15%) compared to dogs with noninfectious pathologies (9%) even prior to the start of their treatment. A 7-day course of ceftriaxone or ceftiofur administrated to CPV and CDV-suspected dogs substantially increased their ESCR-E faecal carriage during treatment (85% for CPV and 57% for CDV), and 4 weeks after the treatment ended (89% for CPV and 60% for CDV) when dogs were back in their households. Most of the observed resistance was carried by ESCR-E. coli carrying bla_CTX-M genes. Our results suggest the need to optimize prophylactic antibiotic therapy in dogs treated for a suspected viral infection to prevent ESCR-E emergence and spread in the community.

Resumen Se evaluó el efecto de la adición en la dieta del aceite esencial de orégano (Origanum vulgare) y de jengibre deshidratado (Zingiber officinale) en la ganancia de peso, consumo de alimento e índice de conversión alimenticia en 624 pollos machos Cobb 500 distribuidos aleatoriamente en cuatro tratamientos y cuatro repeticiones de 39 broilers cada una. Se obtuvieron muestras de intestino e hígado de cuatro aves por tratamiento el día 14 y dos por tratamiento el día 42 del ensayo para determinar posibles alteraciones histológicas por intoxicación y para determinar la histomorfometría de yeyuno. Los tratamientos fueron: APC, Bacitracina disalicilato metileno (1 kg/TM de alimento) y sulfato de colistina 8% (0.25 kg/TM); SPC, sin promotor de crecimiento; AEO, aceite esencial de orégano (1 kg/TM); y JD, jengibre deshidratado (10 kg/TM). No hubo diferencias estadísticas en peso, consumo de alimento ni conversión alimenticia entre grupos experimentales. Las vellosidades del grupo AEO presentaron una ligera aunque no significativa mayor longitud de vellosidades intestinales. Las aves de todos los grupos presentaron alteraciones histológicas en yeyuno e hígado aunque con diferente intensidad. Se concluye que el uso de AEO y JD como promotores de crecimiento no difieren de los otros tratamientos, probablemente por un bajo reto sanitario.

Background/Objectives: Extended-Spectrum Beta-Lactamase-producing Escherichia coli (ESBL-E. coli) are widely circulating in livestock of low- and middle-income countries. However, the drivers of their circulation remain largely unknown. Small-scale farms in Peru exhibit an unusually high prevalence of fecal carriage of ESBL-E. coli in their livestock. The objective of this study was to compare the prevalence of ESBL-E. coli fecal carriage in dairy cows, pigs, and poultry in the Lima and Ica regions of Peru and to identify the drivers associated with the observed prevalence at the farm level. Methods: We compared the prevalence of fecal carriage of ESBL-E. coli isolated from dairy cattle (N = 244 animals; 25 farms), pigs (N = 261; 25), and laying hens (N = 255; 10). We also administrated questionnaires to 59 farmers regarding their socioeconomic status, husbandry practices, animal diseases, and antibiotic use. Results: All but one of the 60 farms sampled had at least one animal carrying ESBL-E. coli. A statistically higher prevalence of ESBL-E. coli was estimated in dairy cows (75%) and pigs (61%) from Lima compared to laying hens from Ica (34%). Our statistical analyses (Poisson generalized linear models) using two variable selection approaches revealed that the prevalence of ESBL-E. coli was lower in farms raising laying hens, when farmers oversaw both animal husbandry and healthcare, and in farms with a lower number of gastrointestinal outbreaks in the last semester. Socio-economic features of farmers and self-reporting antibiotic use varied across farms (i.e., highest antibiotic use over the last semester was reported among pig farmers (96%), followed by laying hen (70%) and dairy cattle farmers (50%)), but these factors were not associated with the prevalence of ESBL-E. coli. Conclusions: Despite a relatively low number of farms sampled, our findings suggest that the widespread circulation of ESBL-E. coli among livestock in Peru could be mainly associated with unknown species-specific drivers, independently of the socioeconomic status of farmers and antibiotic use. Therefore, our study calls for future research to identify the specific drivers promoting the high prevalence of ESBL-E. coli among cattle and pigs in Peru.

Antibiotic-resistant bacteria, such as Extended-spectrum β -lactamase-producing Klebsiella pneumoniae (ESBL- Kp ), represent a major threat to public health. Despite increasing reports of community-acquired ESBL- Kp infections, the dynamics of ESBL- Kp in low- and middle-income countries communities remains poorly understood. This study aimed to detect the fecal carriage of ESBL- Kp at the human–animal–environment interface in Peru and to characterize underlying molecular mechanisms involved. We detected 15 ESBL- Kp isolates among 652 (2.3%) fecal and water samples (i.e., 244 dairy cows from 25 farms, 261 pigs from 25 farms, 58 dogs, 39 farmers, and 50 water sources). ESBL- Kp was isolated from two humans, two dogs, four cows, three pigs, and four water sources. Genomic analyses identified 10 different ESBL- Kp sequence types (STs), including high-risk clones ST11, ST307, and ST37, as well as ST45, ST111, ST1, ST348, ST789, ST881, and ST983, and three CTX-M-encoding genes ( bla _CTX-M-15 , bla _CTX-M-27 , bla _CTX-M-14 ). Four ESBL- Kp STs (ST348, ST983, ST789, and ST11) were found in more than one source, both within and between farms. In particular, two ESBL- Kp ST983 isolates, one from a human and one from a cow on the same farm, differed by 37 SNPs and had almost identical genetic profiles, suggesting bacterial clonal exchange across host species or contamination from a common source. Likewise, two nearly identical ST348 isolates were recovered from a cow and a water source on the same farm, suggesting ESBL- Kp exchange between livestock and water. Our results highlight the circulation of ESBL- Kp across humans, animals, and water in rural environments in Peru, representing one of the first genomic studies exploring potential cross-species ESBL- Kp relatedness in Latin America. Our study supports the need to implement sanitary measures to limit the cross-species spread of antimicrobial-resistant bacteria and to reduce water source contamination in Peru.