Probiotic potential of GABA-producing lactobacilli isolated from Uruguayan artisanal cheese starter cultures.

AIMS: In this study, we sought to identify and characterize a collection of 101 lactobacilli strains isolated from natural whey starters used in Uruguayan artisan cheese production, based on their capacity to produce gamma-aminobutyric acid (GABA) and their probiotic potential. METHODS AND RESULTS: The probiotic potential was assessed using low pH and bile salt resistance assays; bacterial adhesion to intestinal mucus was also evaluated. Selected strains were then identified by 16S sequencing, and their GABA-producing potential was confirmed and quantified using a UHPLC-MS system. Twenty-five strains were identified and characterized as GABA-producing lactobacilli belonging to the phylogenetical groups Lactiplantibacillus (n = 19) and Lacticaseibacillus (n = 6). Fifteen strains of the Lactiplantibacillus group showed a significantly higher GABA production than the rest. They showed the predicted ability to survive the passage through the gastrointestinal tract, according to the in vitro assays. CONCLUSIONS: A set of promising candidate strains was identified as potential probiotics with action on the gut-brain axis. Further studies are needed to assess their possible effects on behaviour using in vivo assay. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows the potential of strains isolated from local natural whey starters as probiotics and for biotechnological use in functional GABA-enriched foods formulation.

Fiebre Q: revisión histórica de casos humanos en Uruguay. Abordaje desde la complementariedad entre las ciencias médicas y veterinarias / Q fever: historical review of human cases in Uruguay. A complementary approach from the medical and veterinarian sciences / Febre Q: revisão histórica de casos humanos no Uruguai. Abordagem a partir da complementaridade entre as ciências médicas e veterinárias

Resumen: La fiebre Q es una zoonosis distribuida mundialmente, causada por Coxiella burnetii. Los bovinos, ovinos y caprinos son la fuente más frecuente de infección en humanos, en los que la enfermedad es de notificación obligatoria ante el Ministerio de Salud Pública. Revisamos las publicaciones que describen casos de fiebre Q en humanos en Uruguay, con foco en sus características epidemiológicas, y discutimos las pruebas diagnósticas disponibles localmente. Se incluyeron nueve trabajos publicados e información del registro de enfermedades profesionales. Colectivamente fueron analizadas 2.715 personas con sospecha de fiebre Q entre 1956-2019, siendo 959 (35,3%) seropositivas. Los diagnósticos se basaron en serología, clínica y/o antecedentes de exposición laboral. Epidemiológicamente, el ganado o material proveniente del mismo fueron considerados las fuentes más probables de exposición en la mayoría de los casos. Según el ámbito de ocurrencia, no sistemáticamente reportado, los casos se registraron principalmente por exposición a ovinos y bovinos en frigoríficos o en la cadena cárnica (positivos/evaluados: 863/1540; seropositivos sintomáticos: 585); y en menor medida a bovinos lecheros (sector lácteo (positivos/evaluados:20/58; seropositivos sintomáticos: 17) y laboratorio diagnóstico (positivos/evaluados:2/4; seropositivos sintomáticos: 1)), o rumiantes silvestres (seropositivos/evaluados:25/117; seropositivos sintomáticos: 17). Hipertermia, cefaleas y sudoración fueron reportados. La inhalatoria fue asumida como la vía de infección en todos los casos. Actualmente no están disponibles localmente pruebas de PCR para detección de C. burnetii en humanos, siendo una limitante en el diagnóstico, particularmente en etapas tempranas. La colaboración interdisciplinaria de profesionales de salud humana y animal es esencial en el abordaje de esta zoonosis.

Summary: Q fever is a globally distributed zoonosis caused by the bacteria Coxiella burnetii. Bovines, sheep and goats are the most frequent source of infection in humans, and it is mandatory for the latter to report the disease to the Ministry of Public Health. We reviewed the literature describing cases of Q fever in humans in Uruguay, focusing on epidemiological characteristics, and we discussed the diagnostic tests locally available. Nine published studies were included in the review, as well as the information in the professional diseases registry. 2.715 people with a suspicion of Q fever were collectively analyzed between 1956-2019, 959 (55.3%) of them being seropositive. Diagnosis were based on serology, clinical examination and/or a history of exposure while working. Epidemiologically, the cattle or material originating in it were considered as the most probable sources of exposure in most cases. Depending on the context cases arose, which were not systematically reported, they were mainly caused by exposure to sheep and cows in meat processing plants or in the meat chain (positive/evaluated: 863/1540; seropositive or symptomatic: 585); and to a lesser extent dairy cattle (milk sector (positive/evaluated: 20/58; symptomatic seropositive: 17) and diagnostic laboratory (positive/evaluated: 2/4; symptomatic seropositive: 1)) or wild ruminants (positive/evaluated: 25/117; symptomatic seropositive: 17). Hyperthermia, headaches and sweating were reported. In all cases inhalation was adopted as the source of infection. Today, there are no PCR tests to detect C. burnetii in humans available locally, what constitutes a limitation to diagnosis, in particular in early stages. Interdisciplinary collaboration between animal and human health professionals is key to approach this zoonosis.

Resumo: A febre Q é uma zoonose mundial causada por Coxiella burnetii. Bovinos, ovinos e caprinos são a fonte mais frequente de infecção em humanos, nos quais a doença é de notificação compulsória ao Ministério da Saúde Pública. Revisamos as publicações que descrevem casos de febre Q em humanos no Uruguai, enfocando em suas características epidemiológicas, e discutimos os testes diagnósticos disponíveis localmente. Foram incluídos nove trabalhos publicados e informações do registro de doenças ocupacionais. Foram analisadas 2.715 pessoas com suspeita de febre Q entre 1956-2019, das quais 959 (35,3%) eram soropositivas. Os diagnósticos foram baseados na sorologia, sintomas e/ou história de exposição ocupacional. Do ponto de vista epidemiológico, o gado ou material preveniente de gado foram considerados as fontes mais prováveis de exposição na maioria dos casos. De acordo com o lugar de ocorrência, não notificado sistematicamente, os casos foram registrados principalmente por exposição a ovinos e bovinos em matadouros ou na cadeia da carne (positivos/avaliados: 863/1540; soropositivos sintomáticos: 585); e em menor proporção gado leiteiro (setor leiteiro (positivo/avaliado: 20/58; soropositivo sintomático: 17) e laboratório de diagnóstico (positivo/avaliado: 2/4; soropositivo sintomático: 1)), ou ruminantes silvestres (soropositivo/avaliado: 25/117; soropositivos sintomáticos: 17). Hipertermia, dores de cabeça e sudorese foram relatados. A inalação foi assumida como via de infecção em todos os casos. Atualmente, os testes de PCR para detecção de C. burnetii em humanos não estão disponíveis localmente, sendo uma limitação no diagnóstico, principalmente em estágios iniciais. A colaboração interdisciplinar de profissionais de saúde humana e animal é essencial no enfrentamento dessa zoonose.

Subclinical bovine mastitis associated with Staphylococcus spp. in eleven Uruguayan dairy farms.

INTRODUCTION: Bovine mastitis is the most common disease affecting the dairy industry, with staphylococci being considered as one of the most significant and prevalent causes. This study aimed to assess the presence of staphylococcal subclinical mastitis (SCM) in Uruguayan dairy farms and to identify Staphylococcus aureus (SA) and non-aureus staphylococci (NAS) in milking cows. In addition, the antibiotic susceptibility of isolated staphylococci was evaluated. METHODOLOGY: We tested 546 apparently healthy milking cows from 11 farms for detecting SCM using the California Mastitis Test (CMT). The cows were not treated with antibiotics. CMT-positive samples were cultured, and colonies compatible with Staphylococcus spp. were further identified through molecular techniques. The susceptibility of the Staphylococcus spp. isolates against thirteen antibiotics was determined using the disk diffusion method. RESULTS: Subclinical staphylococcal mastitis was present in almost all (82%) farms. SA (n = 39) was more common than NAS (n = 9) in the 48 samples tested. Isolates exhibited resistance to one, two, and even three different antibiotics. Resistance to penicillin was the most frequent among SA (23/39) and NAS (4/9). No staphylococci isolates exhibited resistance to cefoxitin, vancomycin, trimethoprim-sulfamethoxazole, erythromycin, or clindamycin. CONCLUSIONS: Staphylococcal SCM is one of the most common diseases in Uruguayan dairy farms. SA was the prevalent pathogen, however SA and NAS mastitis coexisted in many farms. NAS were identified and its distribution was similar to other countries. Penicillin had the highest and most frequent percentage of resistance.

Serological Evidence of Human Infection with Coxiella burnetii after Occupational Exposure to Aborting Cattle.

Cattle are broadly deemed a source of Coxiella burnetii; however, evidence reinforcing their role in human infection is scarce. Most published human Q fever outbreaks relate to exposure to small ruminants, notably goats. Anti-phase II C. burnetii IgG and IgM were measured by indirect fluorescent antibody tests in 27 farm and veterinary diagnostic laboratory workers to ascertain whether occupational exposure to cattle aborting due to C. burnetii was the probable source of exposure. Four serological profiles were identified on the basis of anti-phase II IgG and IgM titres. Profile 1, characterised by high IgM levels and concurrent, lower IgG titres (3/27; 11.1%); Profile 2, with both isotypes with IgG titres higher than IgM (2/27; 7.4%); Profile 3 with only IgG phase II (5/27; 18.5%); and Profile 4, in which neither IgM nor IgG were detected (17/27; 63.0%). Profiles 1 and 2 are suggestive of recent C. burnetii exposure, most likely 2.5-4.5 months before testing and, hence, during the window of exposure to the bovine abortions. Profile 3 suggested C. burnetii exposure that most likely predated the window of exposure to aborting cattle, while Profile 4 represented seronegative individuals and, hence, likely uninfected. This study formally linked human Q fever to exposure to C. burnetii infected cattle as a specific occupational hazard for farm and laboratory workers handling bovine aborted material.