Tuberculosis in Wild Pigs from Argentina.

Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex (MTC) and non-tuberculous Mycobacteria (NTM), may infect wild and domestic mammals, including humans. Although cattle are the main hosts and spreaders of M. bovis, many wildlife hosts play an important role worldwide. In Argentina, wild boar and domestic pigs are considered important links in mammalian tuberculosis (mTB) transmission. The aim of this work was to investigate the presence of M. bovis in wild pigs from different regions of Argentina, to characterize isolates of M. bovis obtained, and to compare those with other previously found in vertebrate hosts. A total of 311 samples from wild pigs were obtained, and bacteriological culture, molecular identification and genotyping were performed, obtaining 63 isolates (34 MTC and 29 NTM). Twelve M. bovis spoligotypes were detected. Our findings suggest that wild pigs have a prominent role as reservoirs of mTB in Argentina, based on an estimated prevalence of 11.2 ± 1.8% (95% CI 8.0-14.8) for MTC and the frequency distribution of spoligotypes shared by cattle (75%), domestic pigs (58%) and wildlife (50%). Argentina has a typical scenario where cattle and pigs are farm-raised extensively, sharing the environment with wildlife, creating conditions for effective transmission of mTB in the wildlife-livestock-human interface.

Serological survey suggests circulation of coronavirus on wild Suina from Argentina, 2014-2017.

Swine coronaviruses affecting pigs have been studied sporadically in wildlife. In Argentina, epidemiological surveillance of TGEV/PRCV is conducted only in domestic pigs. The aim was to assess the prevalence of TGEV/PRCV in wild Suina. Antibodies against these diseases in wild boar and captive collared peccary were surveyed by ELISA. Antibodies against TGEV were found in three collared peccaries (n = 87). No TGEV/PRCV antibodies were detected in wild boar (n = 160). Preventive measures should be conducted in contact nodes where the transmission of agents may increase. Epidemiological surveillance in wildlife populations and in captive animals before their reintroduction should be attempted.

Epidemiology of Pig Tuberculosis in Argentina.

Bovine tuberculosis (bTB) is a disease caused mainly by the Mycobacterium bovis and that is endemic to livestock populations in most Latin American countries. Traditionally, bTB control programs are costly and targeted to cattle, largely disregarding other species such as swine and wildlife. According to official services, in Argentina disease prevalence in pigs is comparable to that observed in cattle, suggesting the need for efficient control programs to manage the disease in both species. Additionally, extensive farming systems, which are commonly practiced in Argentina, allow the interaction between livestock and wildlife such as wild boar (Sus scrofa), which is considered a natural host of the disease. Here, we evaluated the bTB pigs- cattle interface, studying the dynamics of M. bovis isolates in the pig population and identifying farm-level epidemiological variables associated with the disease confirmation at slaughterhouses. Additionally, to assess the potential multi-host systems in the transmission of bTB, the molecular characterization of wild boar mycobacterial strains was included in the study, as this interaction has not been previously evaluated in this region. Multivariable logistic regression models were used to assess the association between farm-level epidemiological variables (location, farm size, and co-existence with cattle and goats) and bTB confirmation in pig tuberculosis-like lesions samples. Results showed that when cattle were present, the odds of bTB in pigs decreased 0.3 or 0.6% for every additional sow when cattle were present or absent in the farm, respectively. Pigs shared 60% (18/30) of the genotypes with cattle and wild boar, suggesting transmission at the interface between pigs and cattle and highlighting the potential role of wild boar in bTB maintenance. These results provide novel information about the molecular diversity of M. bovis strains in pigs in Argentina and proposes the potential relevance of a multi-host system in the epidemiology of bTB in the region. The statistical models presented here may be used in the design of a low cost, abattoir-based surveillance program for bTB in the pig industry in Argentina, with potential extension to other settings with similar epidemiological conditions.

Determinantes de infestación durante un brote de trichinellosis en el sudoeste de la provincia de Buenos Aires / Determinants of infestation during an outbreak of trichinellosis in southwest Buenos Aires province / Determinantes da infecþÔo durante um surto de triquinose no sudoeste da provincia de Buenos Aires

Se estudió la asociación entre infestación, parámetros de laboratorio y signos clínicos en personas expuestas a infestación por Trichinella spiralis durante un brote de trichinellosis en el sudoeste de la provincia de Buenos Aires, Argentina. Asimismo, se investigó el grado de concordancia entre las pruebas inmunoserológicas más comúnmente utilizadas en el diagnóstico de trichinellosis humana. En las personas expuestas, la presencia de síntomas clínicos y los niveles elevados de la enzima creatina fosfoquinasa al día 7 post-exposición se asociaron significativamente con la infestación al día 30 post-exposición. Por el contrario, la eosinofilia (>7%) a los siete días postexposición no se asoció al estado de infestación a los 30 días post-exposición. El mayor grado de concordancia entre pruebas inmunoserológicas se dio entre el par ELISA-Western Blot tanto al día 7 como 30 post-exposición.(AU)

The association between infestation, laboratory parameters and clinical signs was investigated in human patients exposed to Trichinella spiralis during an outbreak of human trichinellosis in southwest Buenos Aires province, Argentina. The degree of agreement between immunoserological tests commonly used for diagnosis of human trichinellosis was determined. Among exposed individuals, the presence of clinical symptoms and high concentration of the creatine phosphoquinase enzyme 7 days post-exposure was significantly associated with infestation by day 30 post-exposure. Contrarily, Randazzo V et al. a high level of eosinophils (>7%) 7 days post-exposure was not associated with infestation by day 30 post-exposure. Test agreement was highest between ELISA and Western Blot both by days 7 and 30 post-exposure.(AU)

Foi estudada a associagáo entre a infestagáo, parámetros laboratoriais e sinais clínicos em pessoas expostas O infestagáo por Trichinella spiralis durante um surto de triquinose, no sudoeste da provincia de Buenos Aires, Argentina. Também se pesquisou o grau de concordáncia entre os testes imunosorológicos mais comumente utilizados no diagnóstico de triquinose humana. Em pessoas expostas, a presenga de sintomas clínicos e os níveis elevados da enzima creatina fosfoquinase no dia 7 pós-exposigáo foram associados significativamente O infestagáo no dia 30 pós-exposigáo. Em contraste, a eosinofilia (> 7%) aos sete dias pós-exposigáo náo foi associada ao estado de infestagáo aos 30 dias pós-exposigáo. O maior grau de concordáncia entre testes imunoserológicos ocorreu entre o par de ELISA-Western Blot tanto no dia 7 quanto no dia 30 pós-exposigáo.(AU)

Determinantes de infestación durante un brote de trichinellosis en el sudoeste de la provincia de Buenos Aires / Determinants of infestation during an outbreak of trichinellosis in southwest Buenos Aires province / Determinantes da infecçâo durante um surto de triquinose no sudoeste da provincia de Buenos Aires

Se estudió la asociación entre infestación, parámetros de laboratorio y signos clínicos en personas expuestas a infestación por Trichinella spiralis durante un brote de trichinellosis en el sudoeste de la provincia de Buenos Aires, Argentina. Asimismo, se investigó el grado de concordancia entre las pruebas inmunoserológicas más comúnmente utilizadas en el diagnóstico de trichinellosis humana. En las personas expuestas, la presencia de síntomas clínicos y los niveles elevados de la enzima creatina fosfoquinasa al día 7 post-exposición se asociaron significativamente con la infestación al día 30 post-exposición. Por el contrario, la eosinofilia (>7%) a los siete días postexposición no se asoció al estado de infestación a los 30 días post-exposición. El mayor grado de concordancia entre pruebas inmunoserológicas se dio entre el par ELISA-Western Blot tanto al día 7 como 30 post-exposición.

The association between infestation, laboratory parameters and clinical signs was investigated in human patients exposed to Trichinella spiralis during an outbreak of human trichinellosis in southwest Buenos Aires province, Argentina. The degree of agreement between immunoserological tests commonly used for diagnosis of human trichinellosis was determined. Among exposed individuals, the presence of clinical symptoms and high concentration of the creatine phosphoquinase enzyme 7 days post-exposure was significantly associated with infestation by day 30 post-exposure. Contrarily, Randazzo V et al. a high level of eosinophils (>7%) 7 days post-exposure was not associated with infestation by day 30 post-exposure. Test agreement was highest between ELISA and Western Blot both by days 7 and 30 post-exposure.

Foi estudada a associagáo entre a infestagáo, parámetros laboratoriais e sinais clínicos em pessoas expostas à infestagáo por Trichinella spiralis durante um surto de triquinose, no sudoeste da provincia de Buenos Aires, Argentina. Também se pesquisou o grau de concordáncia entre os testes imunosorológicos mais comumente utilizados no diagnóstico de triquinose humana. Em pessoas expostas, a presenga de sintomas clínicos e os níveis elevados da enzima creatina fosfoquinase no dia 7 pós-exposigáo foram associados significativamente à infestagáo no dia 30 pós-exposigáo. Em contraste, a eosinofilia (> 7%) aos sete dias pós-exposigáo náo foi associada ao estado de infestagáo aos 30 dias pós-exposigáo. O maior grau de concordáncia entre testes imunoserológicos ocorreu entre o par de ELISA-Western Blot tanto no dia 7 quanto no dia 30 pós-exposigáo.

Mercury levels and health parameters in the threatened Olrog's Gull (Larus atlanticus) from Argentina.

Mercury (Hg) exposure was investigated through feathers of Olrog's Gull and related to health parameters in adults (hematocrit, total plasma proteins, morphometric measures, sex) and chicks (hematocrit, total plasma proteins, immunoglobulins G and M) from a colony located in estuary of Bahía Blanca, Argentina. Mercury concentrations were 5.50 ± 2.59 µg g⁻¹ (n = 44) in live adults, 1.85 ± 0.45 µg g⁻¹ (n = 45) in live chicks and 1.81 ± 0.41 µg g⁻¹ (n = 41) in dead chicks. Large differences were observed between live adults and live or dead chicks and small differences between live and dead chicks. In the adults, the sex of the birds was the variable that best explained Hg concentrations. Male birds had higher concentrations than females; this suggests that the clutch provides a sink for mercury during egg laying. Hg concentrations in both adults and live chicks were associated with higher hematocrits. This could be associated with upregulated erythropoiesis to compensate for increased rate of destruction of prematurely senescent, Hg-contaminated erythrocytes. Based on our results, on the levels of Hg pollution in the past in the study area, and on the dietary specialization of Olrog's Gull, we must be vigilant about potential negative effects of Hg pollution on this population and recommend continued monitoring on this threatened species.