The prevalence and spatial epidemiology of cysticercosis in slaughtered cattle from Brazil

Prevalence of cysticercosis in cattle slaughterhouses in the western region of Minas Gerais, Brazil (2013-2020): Influence of sanitary regulations in reducing risks to human health

Bovine cysticercosis is a foodborne zoonosis that has a worldwide distribution, and its highest prevalence is found in developing countries with a large volume of cattle production, such as Brazil. The objective was to evaluate the prevalence of cysticercosis during seven years in three slaughterhouses located in the western region of Minas Gerais state, Brazil, and the impacts of the legislation on the identification and destination of infected carcasses. Three slaughterhouses (Sl) were selected for this study with averages of 200 (SlA), 721 (SlB) and 1138 (SlC) bovines slaughtered per day. The monthly number of slaughtered cattle, infected carcasses with cysticercosis and destination were used to calculate the condemnation occurrence index (COI) and the adjusted seasonal index (ASI). To assess the impact of the legislation, the prevalence rate and destination of infected carcasses were subdivided into the PRE (January 2013 to March 2017) and POST (April 2017 to December 2020) period of Decree 9013 of 2017 and the results were compared by chi-square (P < 0.05). SlA recorded the highest cysticercosis rate with 1.54 % and SlC the lowest rate with 0.33 %. In addition, it was observed that in the POST period there was an increase in the identification of infected carcasses in SlA and B (P < 0.05). The POST period also resulted in a change in the relative frequency of infected carcasses destination in the three slaughterhouses (P < 0.05). The ASI identified an increase in infected carcasses in February and a decrease in November for SlB, proving to be an important tool for planning the inspection team trainings. These results show that the disease is still present in the studied region and highlight the benefits of using the One Health concept in the evaluation of a time series prevalence of bovine cysticercosis by: identifying seasonality of the disease, trends during the time period and impacts brought by updates in the national sanitary legislation.

Updated spatial analysis of areas of occurrence of bovine cysticercosis in the state of Espírito Santo, Brazil

The risk of bovine cysticercosis is mutable over time, since population habits, local infrastructure, and bovine herd size change through the years. Hence, the aim of this study was to update the risk map of bovine cysticercosis occurrence in Espírito Santo State, Brazil, by choosing the following risk factors: inadequate sewer service; bovine population per municipality; risk of flooding; and land use and occupation, examined with a mathematical model using the GIS program ArcGis 10.5. The risk map of occurrence demonstrated that the state is composed of 12.8, 24.5, 36.2 and 26.5% of areas of very high, high, medium, and low risk, respectively. The northern area stood out for areas of very high risk, with the cities of Linhares and São Mateus accounting for 99% of the area with this classification. Of the state's 78 municipalities, 15 had a portion of their territory with very high risk, 11 had over 50% of the territory with high risk and all except Irupi (100% of low risk) had some percentage of medium risk. These findings demonstrate the areas where actions to prevent bovine cysticercosis should be preferentially conducted.

Bovine cysticercosis in the State of São Paulo, Brazil: Prevalence, risk factors and financial losses for farmers

Taenia saginata is the causative agent of bovine cysticercosis (BCC) and human taeniasis, two diseases that have economical and public health importance, respectively. This research focused on determining BCC prevalence in the state of São Paulo state, Brazil, in the period of 2017-2019, as well as associating risk factors related to disease occurrence and estimate the economic impact to beef producers. Data from 6,277,758 bovine carcasses originating from 571 municipalities and 15 different mesoregions in the state of São Paulo was gathered and analyzed. Cysticerci were detected in a total of 88,700 carcasses at meat inspection, resulting in an apparent prevalence of 1.41 % (C.I. 95 % 1.40-1.42 %). BCC was widespread in this state and its spatial distribution varied in municipalities and mesoregions. The variable number of milking cows in the municipality was significantly associated (OR = 1.48, p = 0.00) with BCC cases, conversely, the presence of peasant's settlements in the municipality was a protective factor (OR = 0.49, p = 0.02). Financial losses for cattle farmers were estimated at US$ 5,829,103.99. The results of this research show that there is still room for implementation of bovine cysticercosis control measures in endemic areas, aiming to reduce financial losses to farmers as well as reduction of human taeniasis cases in the population.

Systematic review and meta-analysis of bovine cysticercosis in Brazil: current knowledge and way forward

Background

Taenia saginata taeniosis/cysticercosis has been well studied in several countries. Brazil is one of the most important beef exporting countries and has one of the highest cattle population size in the world. In this country, bovine cysticercosis (BCC) remains the most frequent reported zoonosis detected during post-mortem inspection, resulting in costs for the beef sector and public health. We performed a systematic literature review regarding data about BCC epidemiology in Brazil and meta-analyses for its prevalence in different administrative regions and the distribution over time, and based on this discussed possible control strategies.

Methods

A systematic review was conducted to obtain data about BCC in Brazil using the words “bovine cysticercosis” and “Brazil” to construct the search phrase. The inclusion criteria used to select articles were: (i) published from 2000 to 2018; (ii) full text available online in Portuguese or English; and (iii) contain information at least regarding one of the following aspects of BCC in Brazil: prevalence, incidence, spatial distribution, risk-factors, economic burden and measures for control.

Results

A set of 42 articles was included, covering the prevalence of BCC in Brazil, ranging between 0.01–18.75%. Prevalence results of 40 articles were included in a meta-analysis per administrative region. The highest prevalence was found in the South (3.4%; 95% CI: 2.0–5.2%), followed by the Southeast (2.7%; 95% CI: 1.9–3.6%), Northeast (1.5%; 95% CI: 0.6–2.7%), Central-western (0.9%; 95% CI: 0.3–1.7%) and North (0.0%; 95% CI: 0.0–0.6%) region. In addition, a reduction in prevalence over time was observed in all the evaluated states except for Alagoas and Pará.

Conclusions

Besides the large availability of data, a critical lack of information about BCC epidemiology remains in Brazil. Nevertheless, the available data on prevalence, high risk-areas and risk factors should contribute to a better understanding of transmission and the formulation of recommendations for control. A One Health approach will be required to reduce T. saginata taeniosis/cysticercosis prevalence and the consequent economic burden for the beef sector in Brazil, one of the most important beef exporters in the world.

Perfil epidemiológico da cisticercose bovina e suína em três regiões do estado de Minas Gerais, Brasil

RESUMO Com o objetivo de avaliar a situação epidemiológica da cisticercose suína e bovina na zona rural de cinco municípios, distribuídos em três distintas regiões do estado de Minas Gerais, foi determinada a prevalência das cisticercoses bovina e suína nas propriedades rurais e os principais fatores de risco que poderiam favorecer a transmissão e manutenção da doença nas referidas propriedades. A pesquisa abrangeu 388 propriedades, localizadas em 91 diferentes comunidades rurais, sendo coletadas 1.792 amostras de sangue bovino e 554 de suíno. Além da avaliação das referidas amostras laboratoriais (ELISA indireto e imunoblot), também foram analisados os dados obtidos da aplicação de um questionário para cada propriedade, no qual constava as informações sobre as condições socioeconômicas, higiênico-sanitárias e as relacionadas ao sistema de criação animal. A prevalência da cisticercose variou de 0,3 a 5,9% nos bovinos e de 0 a 2,8% nos suínos criados artesanalmente nesses municípios pesquisados. Os principais fatores de risco de transmissão identificados foram a fonte de água consumida, a origem da carne, a natureza do município e da região, para a cisticercose bovina, e o destino do esgoto e o sistema de criação, para a cisticercose suína.

Epidemiology of Taenia saginata taeniosis/cysticercosis: a systematic review of the distribution in the Americas

BACKGROUND

The distribution of Taenia saginata in the Americas is unclear. Establishing the distribution, economic burden, and potentials for control of bovine cysticercosis is increasingly important due to the growing demand for beef. This paper aims to take the first step and reviews the recent distribution of T. saginata taeniosis and bovine cysticercosis on a national level within the Americas.

METHODS

We undertook a systematic review of published and grey literature for information on the occurrence, prevalence, and geographical distribution of bovine cysticercosis and human taeniosis in the 54 countries and territories of the Americas between January 1st, 1990 and December 31st, 2017. Data on bovine cysticercosis from OIE reports from 1994 to 2005 were also included.

RESULTS

We identified 66 papers from the Americas with data on the occurrence of taeniosis or bovine cysticercosis and an additional 19 OIE country reports on bovine cysticercosis. Taeniosis was reported from 13 countries, with nine of these countries reporting specifically T. saginata taeniosis, and four countries reporting non-species specific taeniosis. The reported prevalence of taeniosis ranged between 0.04-8.8%. Bovine cysticercosis was reported from 19 countries, nine identified through the literature search, and an additional 10 identified through the OIE country reports for notifiable diseases. The reported prevalence of bovine cysticercosis ranged between 0.1-19%. Disease occurrence was restricted to 21 countries within the Americas, the majority from the mainland, with the only island nations reporting either bovine cysticercosis or taeniosis being Cuba, Haiti, and the US Virgin Islands.

CONCLUSIONS

Taenia saginata is widely distributed across 21 of the 54 countries in the Americas, but insufficient epidemiological data are available to estimate the subnational spatial distribution, prevalence, incidence and intensity of infections. This needs to be addressed through active surveillance and disease detection programmes. Such programmes would improve the data quantity and quality, and may enable estimation of the economic burden due to bovine cysticercosis in the region in turn determining the requirement for and cost-effectiveness of control measures.

Geospatial distribution and risk factors for bovine cysticercosis in the state of Rondônia, Brazil

ABSTRACT: This study focused on assessing the prevalence, geospatial distribution and risk factors for bovine cysticercosis in cattle from the state of Rondônia, Brazil, through the years 2012 to 2015. The prevalence established was 0.014% (95% C.I. 0.013-0.014), with a higher detection of unviable cysticerci (84.80%). The municipalities of Itapuã do Oeste, Candeias do Jamari, Nova Brasilândia D’Oeste, Pimenteiras do Oeste, Porto Velho, Nova Mamoré, Urupá and Guajará-Mirim had higher risk (OR>1; p<0.05) for cysticercosis occurrence compared with the municipality of Castanheiras (OR=1). The Administrative Regions of Porto Velho, Guajará-Mirim, Colorado D’Oeste, Cacoal, Ji-Paraná had higher risk (OR>1; p<0.05) for cysticercosis occurrence in the slaughtered animals than those reared in Ariquemes Administrative Region (OR=1). Some variables such as human population density (OR=2.15; 2.15-2.16), percentage of urban houses with inappropriate sewage system (OR=1.91, 1.91-.1.92) and percentage of inappropriate rural sewage system (OR=1.14, 1.14-1.14) were significantly associated (p<0.05) with the occurrence of bovine cysticercosis. In conclusion, the prevalence of bovine cysticercosis in the state of Rondônia was 0.014% (95% C.I. 0.013-0.014) and higher-risk areas were identified, providing useful information to Official Sanitary Inspection System in order to improve cysticercosis detection. Also, human population density and the lack of appropriate sewage system in urban and rural areas are closely related to bovine cysticercosis occurrence in this state.

Analysis of bovine cysticercosis in the state of Goiás, Brazil and economical losses for beef farms

This study aimed to assess the prevalence and spatial distribution of bovine cysticercosis in the state of Goiás, Brazil; to verify its association with epidemiological variables, and to establish the economical losses for beef farms. A set of 23 255 979 bovines from 246 municipalities were slaughtered from 2007 through 2014. The prevalence of bovine cysticercosis was 0·53% [95% confidence interval (95% CI) 0·5295–0·5354]. The Central mesoregion showed a higher risk [odds ratio (OR) = 4·44; 95% CI 4·2936–4·5895] for detecting infected animals with cysticerci compared with those raised at North and Northeast mesoregion (OR = 1·02 and OR = 1·02). The microregion of Goiânia had a higher risk for bovine cysticercosis occurrence (OR = 11·05, 95% CI 10·6933–11·4099) compared with the microregion of São Miguel do Araguaia (OR = 1). None of the epidemiological variables evaluated in this study was significantly associated (P &gt; 0·05) with bovine cysticercosis prevalence.

In conclusion, the prevalence of bovine cysticercosis in the state of Goiás, Brazil, was 0·53% and some mesoregions and microregions presented a higher risk for its occurrence. The economical losses due to its occurrence during the period ranged from US$9 260 728·57 to 11 313 816·67. These results highlighted the needs of adopting prophylactic measures and the development of political strategies in specific regions in order to control this zoonose and reduce the economical losses for beef production chain and the costs for public health.

Spatial distribution of bovine cysticercosis-A retrospective study in Brazil from 2010 through 2015

Geographical Information Systems (GIS) is frequently used in the control of animal diseases. In Brazil, the most impacting economical loss in the beef supply chain is bovine cysticercosis. This study focused on assessing the prevalence and geospatial distribution of bovine cysticercosis in 19 Brazilian states. To this, we gathered data from 146,346,244 bovines slaughtered between the years of 2010 and 2015. The observed prevalence was 0.62% (C.I. 0.62-0.63). In total, 30.86% cysticerci were viable, while 69.14% were unviable. Bovine cysticercosis cases had a significant decrease (p<0.05) during this period. The states of Paraná (2.01%; C.I. 2.00-2.02), Santa Catarina (1.96%; C.I. 1.93-2.00), São Paulo (1.77%; C.I. 1.76-1.77), Rio Grande do Sul (1.63%; C.I. 1.60-1.63) and Mato Grosso do Sul (0.80%; C.I. 0.80-0.80) had the highest prevalence values. In some states a significant (p<0.05) decreasing trend was detected in the prevalence. In conclusion, Taenia-saginata-cysticercosis remains endemic in Brazil and interventions are necessary to maintain Brazilian beef competitive in the international food market and improve food safety to population.

Spatial analysis of bovine cysticercosis in the state of Mato Grosso do Sul, Brazil - The needs of interventions in animal and human populations

The Taenia saginata-cysticercosis complex is an important zoonosis for public health and an important cause of economical losses for beef supply chain in developing and industrialized countries. Despite some risk factors for high-occurrence areas have already been described, further studies are required to better understand its global epidemiology. So, this study focused on establishing the prevalence, spatial distribution and environmental and human population aspects correlated with bovine cysticercosis prevalence in the state of Mato Grosso do Sul, Brazil. To this, we used data of 7,415,998 animals slaughtered from all 79 municipalities located in this state. Cysticercosis prevalence showed spatial distribution dependence (Moran Index=0.375, p=0.01) and some areas presented higher risk. Positive correlations of bovine cysticercosis prevalence with human population density (R=0.5712, p=3.85 e-08) and rainfall index (R=0.631, p=0.03) were observed. A negative correlation (R=-0.4637, p=2.096 e-05) with cattle population size was also established. These results highlight the importance of adopting sanitary measures to prevent environment contamination, besides other prophylactic measures like the treatment of human patients in order to reduce the Taenia saginata-cysticercosis complex occurrence.

Evaluation of a synthetic peptide from the Taenia saginata 18kDa surface/secreted oncospheral adhesion protein for serological diagnosis of bovine cysticercosis

Bovine cysticercosis is a zoonotic infection widely spread throughout Brazil, creating a burden on hygiene maintenance and the economy. Diagnosis of cysticercosis usually relies on post mortem inspection of carcasses in slaughterhouses. This detection method provides only low sensitivity. Recent advancements have improved the performance of serologic tests, such as ELISA, providing greater sensitivity and specificity. The objective of the current study was to identify and evaluate a synthetic peptide derived from the Taenia saginata 18kDa oncospheric surface protein for the diagnosis of bovine cysticercosis in ELISA. Test performance of the identified peptide was compared to an ELISA based on a heterologous crude Taenia crassiceps antigen (Tcra), widely used for the sero-diagnosis of bovine cysticercosis. Based on the primary sequence of an in silico structural model of the 18kDa protein, an epitope region designated EP1 was selected (46-WDTKDMAGYGVKKIEV-61). The peptide derived from this region yielded 91.6% (CI=80-96%) sensitivity and 90% (CI=82-95%) specificity when used in an ELISA, whereas the crude antigen yielded 70% (CI=56-8%) sensitivity and 82% (CI=73-89%) specificity. Thus, we conclude that EP1 has higher diagnostic potential for detecting bovine cysticercosis than the crude antigen Tcra.

Spatial analysis on the risk of bovine cysticercosis occurrence in the state of Espírito Santo, Brazil

A map of the risk of bovine cysticercosis occurrence was developed for the state of Espírito Santo, Brazil, and it was based in a mathematic model based on following variables: inadequate sewage, bovine population by county, use and occupation of the land and flood risks in GIS environ by means of the ArcGIS/ArcINFO 10.1 program. The work aims to spatially analyze the risk of bovine cysticercosis occurrence in the state of Espírito Santo, by means of risk factors related to cysticercosis and compare with the prevalence obtained from slaughterhouses in the same area. The map of risk showed areas high risk and very high risk located mainly in Ecoporanga, Linhares, counties, where the prevalence from slaughterhouses are low, and in two counties of south macro-region, Presidente Kennedy and Itapemirim, where prevalence from slaughterhouses are higher.

Relevant peptides of Taenia crassiceps for the diagnosis of bovine cysticercosis by immunoblot

Given the limited knowledge about the diagnosis of bovine cysticercosis by immunoblot, the aim of this study was to assess the applicability of this test, identifying key peptides with diagnostic value. Immunoblot assays were performed using total larval antigen of Taenia crassiceps and 60 sera of positive bovines for cysticercosis (30 naturally and 30 experimentally infected with T. saginata eggs), 30 sera of negative bovines for cysticercosis and 30 sera of bovines with other diseases (fascioliasis, hydatidosis and tuberculosis). The peptides of greater diagnostic importance, in descending order of accuracy (%), were as follows: 6-8kDa (90.8%), 129-143kDa (74.2%), 99-105kDa (71.7%) and 14-19kDa (71.1%). Cross-reactions, due to fascioliasis and hydatidosis, were observed in the four intervals of peptides highlighted. The results demonstrate that the total antigen of T. crassiceps has peptides with a high diagnostic potential; therefore, the immunoblot is useful in the diagnosis of bovine cysticercosis.