Consumption Of Undercooked Meat Research Articles

Toxoplasma gondii infection in sheep from Haute-Vienne, France: Seroprevalence and isolate genotyping by microsatellite analysis

Ingesting meat of free-range livestock, mainly sheep, is associated with human toxoplasmosis in European countries. Data on Toxoplasma gondii infection in French ovine livestock are relatively scarce. Sera from 164 lambs and 93 ewes slaughtered in Haute-Vienne district, France, were tested by a direct agglutination test. Antibodies to T. gondii were found in 36 (22.0%) lambs and in 61 (65.6%) ewes. In addition, to attempt parasite isolation for genotyping, hearts from 50 other ewes were obtained from a local slaughterhouse, and were screened by a direct agglutination test. T. gondii was isolated in 8 of 30 seropositive hearts bioassayed in mice. All isolates were type II by genetic characterization at five microsatellite loci ( TUB2, TgM-A, W35, B17, B18). These results indicate that ovines slaughtered in France may be highly infected by T. gondii with a potential risk of parasite transmission to humans by consumption of undercooked meat. Multilocus microsatellite analysis shows the predominance of type II in sheep as previously described in humans.

Enumeration of Campylobacter spp. on the surface and within chicken breast fillets

To investigate how many Campylobacter bacteria are present on the surface and inside chicken breast fillets, with a focus on generating data distributions which can be used in risk assessments for this pathogen-commodity combination. We analysed 100 fresh retail chicken breast fillets (skinless and deboned) by means of a rinse sample for surface and 55 fillets for internal pathogen contamination using 10 g meat and a most probable number technique. Prevalence was 87% on the surface and 20% in the deep tissue. The mean number of Campylobacter on the surface of the fillets was 1903 CFU, with a median of 537 CFU and a maximum of 38,905 CFU. Campylobacter counts inside the tissue were <1 CFU g(-1) meat (mean = 0.24 CFU, median = 0.15 CFU, maximum = 0.74 CFU). In addition, we investigated the influence of the type of package on the occurrence of the pathogen. Data provide an indication of less favourable conditions for survival of the pathogen on chicken meat packed under a modified atmosphere of carbon dioxide in nitrogen, in comparison with ambient air or vacuumed packages. Given the high numbers of the pathogen on the chicken meat surface in comparison with low levels of internal contamination, it can be concluded that cross-contamination during the preparation of contaminated chicken is a more important pathway for consumers' exposure to Campylobacter than the consumption of undercooked meat. The detailed quantitative data on the occurrence of C. jejuni and C. coli on the surface and inside chicken meat presented here can be useful for future probabilistic exposure assessments.

Risk factors for Salmonella Enteritidis and Typhimurium (DT104 and non-DT104) infections in The Netherlands: predominant roles for raw eggs in Enteritidis and sandboxes in Typhimurium infections

Since 1996 Salmonella Typhimurium DT104 salmonellosis has increased in The Netherlands. This prompted a case-control study of risk factors for salmonellosis to inform transmission routes for this phage type. Cases were laboratory-confirmed patients with a Salmonella infection and controls were selected from population registries by frequency matching for age, sex, degree of urbanization and season. Cases and controls received a questionnaire on risk factors. Of the 1171 cases, 573 (49%) responded: 245 S. Enteritidis and 232 S. Typhimurium cases (both DT104 and non-DT104), of which 58 were DT104. Of the 10250 controls, 3409 (33%) responded. Use of H2 antagonists [odds ratio (OR) 4.4, 95% CI 1.6-12.2] and proton pump inhibitors (OR 4.2, 95% CI 2.2-7.9), consumption of raw eggs (OR 3.1, 95% CI 1.3-7.4) and products containing raw eggs (OR 1.8, 95% CI 1.1-3.0) were associated with endemic S. Enteritidis infection. Risk factors for endemic S. Typhimurium infection were use of proton pump inhibitors (OR 8.3, 95% CI 4.3-15.9), occupational exposure to raw meat (OR 3.0, 95% CI 1.1-7.9), playing in a sandbox (for children aged 4-12 years) (OR 2.4, 95% CI 1.6-3.7), consumption of undercooked meat (OR 2.2, 95% CI 1.1-4.1) and use of antibiotics (OR 1.9, 95% CI 1.0-3.4). Use of proton pump inhibitors (OR 11.2, 95% CI 3.9-31.9) and playing in a sandbox (OR 4.4, 95% CI 1.8-10.7) were the only risk factors for S. Typhimurium DT104 salmonellosis. This study confirms known risk factors for salmonellosis. However, playing in a sandbox was a predominant new risk factor for S. Typhimurium salmonellosis in children [population attributable risk (PAR) 14%], and especially for S. Typhimurium DT104 (PAR 32%).

Cross-sectional survey on Toxoplasma gondii infection in cattle, sheep and pigs in Serbia: Seroprevalence and risk factors

Toxoplasmosis is a globally distributed zoonosis with a clinical impact in the unborn fetus and in the immunosuppressed individual. In Serbia, studies of risk factors for Toxoplasma gondii infection in humans have shown that the relatively high prevalence is associated mainly with consumption of undercooked meat and/or meat products. However, data on T. gondii infection in domestic animals mostly used for human consumption are scarce. We thus conducted a cross-sectional survey on the seroprevalence of T. gondii infection in a representative sample of cattle, sheep and pigs from different regions of Serbia between June 2002 and June 2003, and analyzed the main risk factors associated with the infection. Sera from 611 cattle (yearlings and adults of both sexes), 511 ewes, and 605 pigs (market-weight and sows), were examined for T. gondii antibodies by the modified agglutination test. The seroprevalences determined were 76.3% in cattle, 84.5% in sheep and 28.9% in pigs. The antibody levels ranged from 1:25 to 1:400 in cattle, and up to 1:25,600 in sheep and to 1:12,800 in pigs. Among the seropositive, the proportion of high antibody levels (≥1:1600), suggestive of acute infection, was 10% in sheep, and 4% in pigs. Possible association of the infection with biologically plausible risk factors including gender, age, herd size/farm type, type of housing, feeding practices and region, was analyzed by univariate analysis, and variables significant at P ≤ 0.1 were included in multivariate logistic regression models. The results showed that risk factors for cattle were small herd size (odds ratio, OR = 2.19, 95% confidence interval, CI = 1.28–3.75, P = 0.004) and farm location in Western Serbia (OR = 2.04, 95% CI = 1.10–3.79, P = 0.024), while housing in stables with access to outside pens was protective (OR = 0.37, 95% CI = 0.21–0.67, P = 0.001). In sheep, an increased risk of infection was found in ewes from state-owned flocks (OR = 4.18, 95% CI = 2.18–8.00, P < 0.001) vs. private flocks, and, interestingly, also in those from Western Serbia (OR = 4.66, 95% CI = 1.18–18.32, P = 0.028). In pigs, the risk of infection was highly increased in adult animals (OR = 3.87, 95% CI = 2.6–5.76, P < 0.001), as well as in those from finishing type farms (OR = 3.96, 95% CI = 1.97–7.94, P < 0.001). In addition to providing data on the current T. gondii seroprevalence in meat animals in Serbia, the results of this study show the main risk factors associated with infection, thereby pointing to the type of preventive measures to reduce T. gondii infection.

Factores de riesgo en mujeres embarazadas, infectadas por Toxoplasma gondii en Armenia-Colombia

To determine the risk factors associated with acute toxoplasmosis during pregnancy in Armenia. Case-control study; 14 cases and 34 controls (mean ages 23 +/- 5.5 and 23 +/- 5.1 respectively; p = 0.93). Cases were pregnant women with serological criteria for acute toxoplasmosis and controls were seronegative pregnant women for Toxoplasma IgG. The risk factors more strongly predictive of acute toxoplasmosis in pregnant women were: eating undercooked meat (OR: 13.2; 95% CI: 1.3-132; p = 0.01), drinking beverages prepared with un-boiled water (OR: 4.5; 95% CI: 1.1-17; p = 0.01), and contact with cats aged less than 6 months (OR: undefined, p = 0.01). Drinking of bottled water was a protective factor (OR: 0.24; 95% CI: 0.06-0.95; p = 0.02). 42% of Toxoplasma gondii infections in pregnant women Armenia were associated to contact with young cats and to consumption of undercooked meat. Drinking of bottled water to prevent toxoplasma infection during pregnancy is also recommended.

Prevention of Toxoplasmosis in Pregnancy: Knowledge of Risk Factors

BACKGROUND: Infection with Toxoplasma gondii is common and usually asymptomatic, although it can have catastrophic consequences in a pregnant woman if passed to her developing fetus. Counseling of pregnant women about risk factor reduction may reduce the risk of congenital toxoplasmosis. This study was undertaken to assess and compare the knowledge of obstetricians and internists or family practitioners regarding well-established risk factors for toxoplasmosis infection. METHODS: The study surveyed 102 obstetricians, internists and family practitioners to assess their knowledge of risk factors for toxoplasmosis infection as well as their practices for primary prevention counseling of pregnant women. Responses were analyzed for differences. RESULTS: Obstetricians were more likely than internists or family practitioners to provide appropriate counseling on reducing the two most common risk factors for toxoplasmosis infection (undercooked meat consumption and gardening without gloves). However, over one quarter of all participants inappropriately advised pregnant women to avoid all cat contact. Obstetricians, internists and family practitioners were all likely to fail to identify undercooked meat consumption as the primary risk factor for toxoplasmosis transmission. CONCLUSIONS: Obstetricians appear to provide more appropriate counseling for primary prevention of toxoplasmosis than internists and family practitioners, but both groups of physicians inappropriately advised avoidance of all cat contact. Education of obstetricians, internists and family practitioners on risk factors for toxoplasmosis transmission is needed and may lower the rate of congenital toxoplasmosis as well as decrease the frequency of cat abandonment during pregnancy.

Identification of risk factors for infection with Toxoplasma gondii in Serbia as a basis of a program for prevention of congenital toxoplasmosis

Toxoplasmosis has long been known as a major cause of perinatal morbidity. Acute infection in pregnancy may lead to fetal infection and subsequent fetal loss or birth of a manifestly or latently infected infant. However, it is a preventable disease. In Europe, significant variations have been shown to occur not only between countries but also within a given country indicating local variations in the influence of epidemiological factors contributing to infection. Thus, many European countries have implemented prevention programs in measure with the respective estimated risk of congenital toxoplasmosis. Since in view of its cost, a general screening-in-pregnancy program is at present not an option in Serbia & Montenegro, insight into the risk factors of particular local significance may therefore improve the quality of and the compliance with the hygienic and dietetic advice given to pregnant women as a preventive measure, as well as identify the particular subpopulations at an increased risk of infection, who may then be selectively screened. A retrospective study of risk factors for Toxoplasma gondii infection based on serological and epidemiological data (questionnaire) was performed in a series of 2936 women aged 15-49 years from throughout Serbia tested in our laboratory between 1988 and 1997. Inclusion criteria included availability of serological and epidemiological data (as specified below). Specific anti-Toxoplasma antibodies were detected by the reference Sabin-Feldman dye test as modified by Desmonts into the lysis test. The questionnaire included questions on age (stratified into five-year groups), degree of education (modalities: grade school, secondary or university level), and community of residence (urban/suburban), as well as on life-style habits pertaining to infection transmission risk factors: consumption of undercooked meat, exposure to soil, and exposure to cats (pet cat ownership). In addition, the year of entry into the study was taken as a variable per se. The difference in the rates of infection between groups was evaluated by the chi-square test (chi 2). Logistic regression (univariant and multivariant approaches) was used to analyze the association between Toxoplasma infection and the specific demographic and epidemiological factors. The overall prevalence of infection was 69%, but with very wide variations both over time (decreasing from 86% in 1988 to 39% in 1997) and region (40-90%). The risk of infection increased from the south to the north (RR = 0.97, CI = 0.94-0.98). Within Belgrade, the risk was higher in urban than in suburban zones (RR = 0.79, CI = 0.64-0.93). The single infection transmission factor that was shown to be a predictor of infection in the whole study group was undercooked meat consumption (RR = 1.6, CI = 1.2-2.1), while exposure to soil was a predictor only in women aged 15-19 (RR = 10.3, CI = 2.7-38.6). Owing pet cats had no influence. While T. gondii infection was not associated with pathological pregnancies (p = 0.51) in the whole study population, it was significantly associated with pathological pregnancies in women exposed to both undercooked meat consumption (p = 0.009) and in those aged 15-19 in contact with soil (p = 0.022), as well as in women residing in highly urban communities (p = 0.048). The dramatic decrease in the prevalence of T. gondii infection over the nineties resulted in a rising proportion of women exposed to infection in pregnancy and consequently in an increased risk of congenital toxoplasmosis. Since the financial status of the country's health system does not allow for a general screening-in-pregnancy program, we propose, based on the above data, health education of all pregnant women in combination with serological testing of those exposed to predictors of infection as an epidemiologically sound and financially sustainable alternative.

First isolation of the enterohaemorrhagic Escherichia coli O145:H- from cattle in feedlot in Argentina

BackgroundEnterohaemorrhagic Escherichia coli (EHEC) is considered to be common cause of haemorrhagic colitis (HC), thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome (HUS) in humans. In a previous paper, we have demonstrated that EHEC are commonly found in the intestines of livestock. Infections in humans are, in part, a consequence of consumption of undercooked meat or raw milk. Argentina has one of the highest records of HUS (300–400 cases/year; 22/100,000 children under 4 years of age). The aim of this work is to communicate the first isolation of O145:H-from cattle in this country and characterize the virulence cassette, providing useful information to evaluate the risk of foodborne transmission of this emergent non-O157:H7 serotype.ResultsEHEC O145:H- was isolated from cattle in an Argentinian feedlot. Pheno- and genotype of nine strains were characterized, corresponding to several virulence cassettes: VT2+eaeA+ Mp+ (n = 5), VT2+eaeA+ (n = 1), VT1+eaeA+ Mp+ (n = 2), and VT1+eaeA+ (n = 1). Strains isolated from the same animal were considered only when they showed a different virulence pattern. The clonal relationship was studied by RAPD. Strains were distributed in two RAPD profiles, which corresponded to the presence of either, VT1+ or VT2+ genotype. No difference was detected by RAPD analysis between Mp+ or Mp- strains.ConclusionsThis was the first isolation of EHEC O145:H- serotype in Argentina enlarging the list of non-O157:H7 serotypes isolated from cattle in this country by us. All O145:H-strains carried several virulence factors which allow us to predict their potential ability to develop haemolytic uraemic syndrome in humans.

Negotiating Bacteriological Meat Contamination Standards in the US: The Case of E.coli O157:H7

The paper analyzes changes in bacteriological meat contamination standards in the us since the early 1980s when E.coli O157:H7 was for the first time identified as a new foodborne pathogen associated with the consumption of undercooked meat. Four types of risks, and the standards associated with them, are identified. Up until 1982 meat contamination was ascertained via organoleptic standards. Meat was considered as safe as producers' and/or consumers' sanitary conditions and hygiene. In 1982,the identification of E.coli O157:H7 as a pathogen dangerous to human health resulted in a redefinition from organoleptic to biomedical standards. Meat contamination risks were measured by the extent to which sick patients could recover from foodborne diseases or die. In 1993,as a result of the massive ‘Jack‐in‐the‐Box outbreak’ associated with the consumption of hamburgers contaminated with E.coli O157:H7,biomedical standards were reformulated into epidemiological measures aimed at ascertaining the extent to which the country's population was at risk of getting sick or dying from meat contamination. Finally, in 1996,with the enactment of the Pathogen Reduction Act/haccp, meat processing standards replaced epidemiological standards. Meat was to be as safe as packers processed it. Economic, political, social, scientific and technological factors contributing to the origins of each of the four types of bacteriological meat standards are analyzed. Consequences of the changes in standards in terms of re‐distribution of costs, benefits, and risks to those social actors engaged in the meat subsector are discussed.

Risk factors for Toxoplasma infection in a reproductive age female population in the area of Belgrade, Yugoslavia.

The contribution to Toxoplasma infection of known transmission risk factors such as consumption of undercooked meat, contact with soil, and contact with cats, as well as that of age, degree of education, residence in central vs. suburban city communities, and year of entry into the study, has been investigated in a group of 1157 female residents (age range 15 to 45 years) of a defined geographic area (Belgrade) during a 4-years period (1988-1991). The rate of infection increased with age, ranging from 57% to 93%, with an overall mean of 77%. However, it decreased significantly over the study period (p < 0.01). Of the potential risk factors examined, regression analysis showed that the following: age (relative risk (RR): 1.18, 95% confidence interval (CI): 1.02-1.37, p = 0.022), undercooked meat consumption (RR: 2.22, 95% CI: 1.2-2.86, p = 0.001), and the year of entry into the study (RR: 0.69, 95% CI: 0.6-0.8, p = 0.000) were significantly associated with infection. However, while the consumption of undercooked meat contributed to the frequency of infection in the whole group, its significance increased with the degree of education but decreased with age, and was greater in women residing in the suburbs. In addition, in women below age 20, exposure to soil (farming, gardening) was significantly associated with infection (RR: 1.38, 95% CI: 1.12-1.97, p = 0.037). Since cats are the single source of toxoplasma oocysts, the above finding indicates that cats are an epidemiologically significant source of environmental contamination in Belgrade. However, cat ownership itself as a criterion of contact with cats was not associated with infection (p = 0.326). In the absence of a general screening in pregnancy program in Yugoslavia, these data point out the groups of pregnant women at the highest risk of infection and provide a basis for a region-appropriate educational program to prevent congenital toxoplasmosis.

The seroepidemiology of toxoplasmosis in the lower Fraser Valley of British Columbia.

To determine the seroprevalence of toxoplasmosis in vegetarian and nonvegetarian members of different ethnic communities in the lower Fraser Valley of British Columbia. Serum samples were collected from 2027 participants drawn from various ethnic groups and tested by elisa for the presence of immunoglobulin (Ig) G and IgM antibodies to Toxoplasma gondii. Coded questionnaires requesting information relevant to the study were completed by each participant. The study population comprised 1334 females and 693 males; ages ranged from 17 to 102 years. Four hundred and nineteen (20.7%) individuals were IgG positive with titres ranging from 1:100 to 1:3200. IgM antibodies were detected in only four individuals. The seroprevalence rose with increase in age but there was no significant difference between males and females. A positive correlation was shown between ingestion of meat and between consumption of unpasteurized milk and antibodies to T gondii. Eighty per cent of females between the ages of 17 and 40, of all ethnic origins, were seronegative. Seropositivity did not differ between cat owners and non-cat owners. Women of childbearing age are at risk of acquiring toxoplasmosis during pregnancy and of transmitting the infection transplacentally. Consumption of undercooked meat and unpasteurized milk may result in the acquisition of toxoplasmosis. Data suggest that acquisition of toxoplasmosis is more likely via environmental oocysts or cysts in food source animals than by direct contact with cats.

Prevalence of toxoplasma IgG among pregnant women in west London according to country of birth and ethnic group.

Infection with Toxoplasma gondii can be acquired from soil contaminated by cats' faeces and by consumption of undercooked meat and unpasteurised goats' milk.' Toxoplasma cysts are killed by freezing or by heating above 45°C.' Matemal infection can result in fetal infection and damage and is estimated to occur in 0 1-05% of pregnancies in the United Kingdom.2 The seroprevalence of toxoplasma IgG is known to vary among countries,' but differences according to country of birth and ethnic group have not previously been investigated in a single population based study.