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- Outbreaks of abortions byCoxiella burnetiiin small ruminant flocks and a longitudinal serological approach on archived bulk tank milk suggest Q fever emergence in Central PortugalPublication . Cruz, Rita; Esteves, Fernando; Vasconcelos-Nóbrega, Carmen; Santos, Carla; Ferreira, Ana S.; Mega, Cristina; Coelho, Ana C.; H, Vala; Mesquita, João R.Q fever is a worldwide zoonotic infectious disease caused by Coxiella burnetii and sheep and goats are known to be the main reservoir for human infection. This study describes the epidemiological and laboratory findings of C. burnetii outbreaks affecting sheep and goat flocks and also provides the results of a prospective serosurvey in bulk tank milk samples to assess C. burnetii circulation in a population of sheep living in close contact to the human population in Central Portugal. In the epizooties, C. burnetii was identified in tissues of the resulting abortions by qPCR. As for the serological survey, 10.2% (95%CI: 4.5‐19.2) of the 78 bulk tank milk samples collected in 2015 presented IgG antibodies against C. burnetii. The same farms were visited and sampled in 2016 and 25.6% (95%CI: 16.4‐36.8) were positive. This steep increase in the number of anti‐C. burnetii farms between the 2015 and 2016 collections showed to be statistically significant (p = 0.020) and is strongly suggestive of Q fever emergence in Central Portugal. Measures on animal health and on disease spread control to the human population should be considered.
- A 2-Year Longitudinal Seroepidemiological Evaluation of Toxoplasma gondii Antibodies in a Cohort of Autochthonous Sheep from Central PortugalPublication . Almeida, Daniela; Quirino, João; Barradas, Patrícia Ferreira; da Silva, Priscilla Gomes; Pereira, Maria; Cruz, Rita; Santos, Carla; Mega, Cristina; Esteves, Fernando; Nóbrega, Carmen; Vala, Helena; Gärtner, Fátima; Amorim, Irina; Mesquita, João R.Background: Toxoplasma gondii is an important zoonosis and one of the major causes of abortion in sheep worldwide. (2) Methods: We performed a 2-year longitudinal serological antiT. gondii IgG screening on a cohort of a spatially confined population of a Portuguese autochthonous sheep breed in central Portugal. (3) Results: From the screening of the 2015 and 2016 sera, an increase of seroprevalence was observed (57.7% (95% CI: 49.9–65.3%) versus 69.1% (95% CI: 61.5–75.9), from 2015 and 2016, respectively) (p = 0.031). (4) Conclusions The present study is the first to provide prospective data on the anti-T. gondii serological status of a sheep cohort in Portugal, showing an increase in the occurrence of T. gondii. There is a need to provide a clearer understanding of T. gondii epidemiology in Portugal, ideally by implementing monitoring programs on sentinel herds, not only due to the high impact of T. gondii on animal health but also for it being a zoonosis.
- A Questionnaire-Based Survey on the Long-Term Management of Canine Leishmaniosis by Veterinary PractitionersPublication . Pereira, Maria; Santos, Rute; Nóbrega, Carmen; Mega, Cristina; Cruz, Rita; Esteves, Fernando; Santos, Carla; Mesquita, João R.; Vala, Helena; Santos-Gomes, GabrielaCanine Leishmaniosis (CanL) is a chronic and potentially fatal disease. In economically disadvantaged regions, costs associated with long-term patient monitoring may determine that some owners decline veterinary follow-up of their dogs. This online, questionnaire-based survey aimed to assess how Portuguese veterinary practitioners perform long-term patient monitoring and recognize relapses. More than 50% of respondents reported that 50–100% of dog owners declared financial restraints. Hence, in these circumstances, most veterinary practitioners only performed clinical examination and serology. However, when owners did not declare financial restriction, other tests were additionally performed, such as renal and hepatic profiles, hemogram, serum protein electrophoresis and urine protein creatinine ratio. The mean number of exams performed when owners presented financial restraints was significantly lower than the number of exams performed without economic limitations. Most veterinary practitioners prescribed allopurinol ad aeternum oruntil disease remission and domperidone. CanL relapses were recognized by more than half of respondents “Always”, through the reappearance or worsening of clinical signs, whereas about a quarter detected an increase in anti-Leishmania antibody levels and identified abnormalities in the serum protein electrophoresis profile. The relapse rate was higher in the Lisbon Metropolitan Area and north, the most economically favored regions of Portugal. This study confirms that owner financial restraints negatively influence veterinary follow-up and relapse recognition, ultimately compromising clinical decision making and favoring the maintenance of Leishmania infantum infection endemicity.
- Prevalence of Toxoplasma gondii Antibodies in Individuals Occupationally Exposed to Livestock in PortugalPublication . Almeida, Daniela; Quirino, João; Matos, Pedro; Esteves, Fernando; Cruz, Rita; Vala, Helena; Mesquita, João R.Toxoplasmosis is a worldwide zoonotic disease with different and complex routes for transmission. Workers occupationally exposed to animals or raw meat and viscera (WOE) may be at more risk than the general population, however conflicting data exist on the risk of developing toxoplasmosis due to this close contact. To add knowledge to this topic, the aim of the present study was to ascertain if WOE were more likely to be anti-T. gondii IgG seropositive than the general population as well as to study risk factors for T. gondii infection such as professional activity, gender, age, years of work and region. For this purpose, a case–control study using archived samples was setup. A total of 114 WOE (including pig slaughterhouse workers, butchers, veterinarians and farmers) and 228 anonymous volunteers (matched with cases by region, age and gender) were studied for anti-T. gondii IgG. A significantly higher anti-T. gondii IgG occurrence (p = 0.0282) was found in WOE when compared with the general population (72.8% [CI = 64.6–81.0%] versus 60.1% [CI = 54.6–65.6%]). Multivariate analysis showed that WOE of more than 50 years of age were more likely to be seropositive for anti-T. gondii IgG (aOR = 16.8; 95% CI 3.6–77.5; p < 0.001) than those aged less than 50 years. To our knowledge, this is the first case–control study on the prevalence of antiT. gondii IgG in WOE in Portugal, also showing an added risk for T. gondii infection in those exposed to animals or their meat and viscera.
- Rickettsia massiliae circulation in sheep and attached Rhipicephalus sanguineus in Central PortugalPublication . Mesquita, João R.; Santos-Silva, Sérgio; de Sousa Moreira, Alícia; Baptista, Maria Beatriz; Cruz, Rita; Esteves, Fernando; Vala, Helena; Barradas, Patrícia F.Rickettsiosis is considered an emerging/re-emerging vector-borne disease that causes signifcant public health threats. Ticks are reservoirs and vectors of Rickettsia having a signifcant role in the transmission of rickettsiae. In Portugal, little is known about tick-borne Rickettsia species in sheep. Therefore, this study aimed to investigate rickettsiae infection in ticks and their sheep host from 27 farms in four districts of central Portugal, to clarify the role of the sheep host in the circulation of this zoonotic agent. Between March and May 2021, EDTA blood samples (n=100) of healthy grazing sheep and their ticks (n=100, one tick per animal) were collected during a herd health program in central Portugal. Obtained ticks were identifed as Rhipicephalus sanguineus sensu lato by PCR targeting a partial sequence of 16S rRNA gene followed by sequence analysis. Rhipicephalus sanguineus s.l. and host sheep blood were tested for the presence of Rickettsia spp. by PCR targeting a partial sequence of ompB and ompA genes. From a total of 100 paired R. sanguineus s.l. and host sheep, Rickettsia massiliae was detected in 62 ticks and 35 grazing sheep blood samples, collected in central Portugal, 2021. All 35 positive sheep had attached positive R. sanguineus s.l., with matching nucleotidic sequences. These fndings suggest that sheep may develop rickettsiemia and are likely capable of transmitting and amplifying the infection to uninfected ticks maintaining rickettsiae in circulation in the domestic cycle.
- Bulk-Tank Milk Longitudinal Serosurvey Reveals Decreasing Schmallenberg Virus Circulation in a Confined Population of Portuguese SheepPublication . Esteves, Fernando; Cruz, Rita; Nóbrega, Carmen; Santos, Carla; Ferreira, Ana S.; Petrovic, Tamas; Cardoso, Luís; Vala, Helena; Nascimento, Maria S.J.; Mesquita, João R.Introduction: In 2011, Schmallenberg virus (SBV) was first detected in dairy cattle herds in The Netherlands and Germany having since then spread across Europe. Today studies are starting to show a decrease in new SBV infections, a circumstance that raises alerts for possible re-emergence if ideal conditions for vector development occur. To assess the potential decrease in SBV circulation, we performed a 2-year longitudinal serological investigation for SBV infection at the herd level by using bulk-tank milk of a specific sheep breed from central Portugal. Materials and Methods: Bulk-tank milk samples from 68 flocks were collected in both 2015 and 2016, and lactosera were tested for IgG anti-SBV by EIA. Results and Discussion: Results show that in 2015, 92.6% (95% confidence interval [CI]: 83.9–96.8) of the bulk-tank milk samples were positive, whereas in 2016 only 77.9% (95% CI: 66.7–86.1 of the samples from the same flocks were positive. Differences in the 2015/2016 seroprevalences showed to be statistically significant (p = 0.027). This significant decrease at the herd level seems to be in agreement with reported data from other European countries and raise alerts, since increasingly favorable conditions (higher number of susceptible animals) are now present, potentially favoring SBV epidemics if improved conditions for midge replication occur in the future.
- Prevalence of Toxoplasma gondii Antibodies and Risk Factor Investigation in Portuguese Veterinarians: A Matched Case Control StudyPublication . Almeida, Daniela; Santos-Silva, Sérgio; Pereira, Maria; Santos, Carla; Mega, Cristina; Coelho, Catarina; Nóbrega, Carmen; Esteves, Fernando; Cruz, Rita; Vala, Helena; Mesquita, João R.Background: Toxoplasma gondii is a widespread zoonotic agent that greatly impacts Public Health, being responsible for one of the most important parasitic zoonosis worldwide. T. gondii has a heteroxenous life cycle, with cats being the definitive hosts and all warm-blooded animals, including humans, being intermediate hosts. Veterinary practitioners (VP) may be at a higher risk than the general population for T. gondii infection, as they have direct and daily contact with many animal species. The aim of the present study was to ascertain if VP were more likely to be anti-T. gondii IgG seropositive than the general population, as well as to understand if age, accidents with blood-contaminated sharps (cross-blood contamination), gender, working years, and geographic regions play a role as risk factors for T. gondii infection. For this purpose, a case–control study using archived samples was performed. (2) Methods: A total of 350 veterinary practitioners were tested using a commercial semiquantitative enzyme immunoassay for anti-T. gondii IgG. From the general population, 175 anonymous volunteers (matched with cases by region, age, and gender) were studied for anti-T. gondii IgG. (3) Results: There was no statistical difference found between the presence of anti-T. gondii IgG in practitioners (26%; CI = 21.40–30.60%) and the general population (33.14%; CI = 26.17–40.12%) (p = 0.108). Univariate and multivariate analysis showed that only age (older groups) was found to be associated with a higher prevalence of anti-T. gondii IgG, with significant p values (p < 0.05) for both univariate and multivariate analysis. (4) Conclusions: To the best of our knowledge, this is the first case–control study fully focused on the prevalence of anti-T. gondii IgG in VP in Portugal, showing that there was no significant risk for T. gondii infection in veterinarians exposed daily and repeatedly to different species of animals.
- Molecular evidence of sporadic Coxiella burnetii excretion in sheep milk, central PortugalPublication . Pires, Humberto; Santos-Silva, Sérgio; Cruz, Andreia V.S.; Cardoso, Luís; Lopes, Ana Patrícia; Pereira, Maria; Nóbrega, Carmen; Mega, Cristina; Santos, Carla; Cruz, Rita; Esteves, Fernando; Vala, Helena; Matos, Ana Cristina; Barradas, Patrícia F.; Coelho, Ana Cláudia; Mesquita, João R.Coxiella burnetii is the etiologic agent of Q fever, a worldwide zoonosis. Cattle, sheep and goats are considered the main reservoirs of the disease. Transmission to humans occurs mainly through the inhalation of infectious aerosols from milk, faeces, urine, and birth products from infected ruminants. In this study, a 2-year longitudinal approach was performed to ascertain the excretion of C. burnetii in bulk tank milk samples of sheep from a mountain plateau in central Portugal, with sampling conducted during the years 2015 and 2016. From a total of 156 bulk tank milk samples tested by qPCR, only one showed to be positive for C. burnetii (1.28% [95%CI: 0.03–6.94]), from 2015, the first year of collection. Bidirectional sequencing and phylogenetic analysis of IS1111 transposase partial region confirmed the presence of C. burnetii DNA. The presence of C. burnetii in raw milk samples highlights the necessity for additional research to determine if raw milk is a potential source for human infection. Animal health surveillance and prevention measures against this zoonotic disease should be considered.