Municipal waste is a potential source of infection for Toxoplasma gondii as it may contain contaminated meat with parasite tissue cysts and cat excrement with parasite oocysts. Therefore, we sought to determine the prevalence of T. gondii infection and associated characteristics in two populations exposed to municipal solid waste in Durango, Mexico. Ninety waste pickers and 83 waste workers of Durango City, Mexico were examined for T. gondii infection. They were tested for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. In addition, socio-demographic and behavioural characteristics from each participant were obtained. Nineteen (21.1%) of the 90 waste pickers and seven (8.4%) of the 83 waste workers were positive for anti-T. gondii IgG antibodies. The difference in prevalence among the groups was statistically significant (P =0.03). Waste pickers aged 31-50 years showed a significantly higher prevalence (40.9%) than waste workers of the same age group (2.9%, P < 0.001). Anti-T. gondii IgM antibodies were found in two (2.2%) of the waste pickers but in none of the waste workers. The seroprevalence of T. gondii was significantly higher in workers of the waste transfer station (25.0%) than in drivers or helpers of waste vehicles (2.5%) (P =0.03). Multivariate analysis showed that T. gondii infection was associated with consuming food found in the garbage [adjusted odds ratio (OR) = 4.4; 95% confidence interval (CI) 1.6-11.8] and with lack of education (adjusted OR = 3.2; 95% CI 1.1-8.8). From this study, we conclude: (i) waste pickers may represent a risk group for T. gondii infection; (ii) lack of education might be a contributing factor for T. gondii infection; (iii) the higher the exposure to garbage, the higher the seroprevalence of T. gondii infection; (iv) Eating food products from the garbage may represent an important route for T. gondii infection.

Little is known concerning the epidemiology of Toxoplasma gondii infection in people and animals in rural Mexico. Serum samples and tissues from 150 dogs (Canis familaris), 150 cats (Felis catus), 65 opossums (Didelphis virginianus), 249 rats (Rattus spp.), 127 mice (Mus musculus), and 69 squirrels (Spermophilus variegatus) from the Durango area were evaluated for T. gondii infection. Using a modified agglutination test and a serum dilution of 1:25, antibodies to this parasite were found in 68 (45.3%) of 150 dogs, 14 (9.3%) of 150 cats, 11 (16.6%) of 66 opossums, 2 (0.8%) of 249 rats, 4 (3.1%) of 127 mice, and 0 of 69 squirrels. Tissues (brain and heart) of dogs, cats, opossums, rats, mice, and squirrels were bioassayed in mice for the presence of T. gondii. Viable T. gondii was isolated in tissues from 3 of 28 seropositive dogs and 5 of 8 seropositive cats, but not from the other animals. The DNA obtained from the 3 T. gondii isolates from dogs, 6 isolates from 5 cats, and 4 isolates from free-range chickens from Mexico, previously isolated, were genotyped. The PCR-RFLP typing, which used 11 markers (B 1, SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico), identified 5 genotypes. One genotype (the 4 chicken isolates) belongs to the clonal Type III lineage, three genotypes were reported in previous reports, and 1 genotype is unique.

Toxoplasma gondii and Neospora caninum are structurally similar parasites, with many hosts in common. The prevalence of antibodies to T. gondii and N. caninum was determined in sera from dogs from Durango City, Mexico. Using a modified agglutination test, antibodies to T. gondii were found in 52 (51.5%) of the 101 dogs with titers of 1:25 in 27, 1:50 in 11, 1:100 in 5, 1:200 in 4, 1:400 in 2, 1:800 in 2, and 1:3,200 or higher in 1. Antibodies to N. caninum were determined by the indirect immunofluorescent antibody test (IFAT) and the Neospora sp. agglutination test (NAT). Two of the 101 dogs had N. caninum antibodies; these dogs did not have T. gondii antibodies, supporting the specificity of the tests used. The N. caninum antibody titers of the 2 dogs were: 1:400 by IFAT and 1:200 by NAT in 1, and 1:25 by NAT and IFAT in the other. Results indicate that these 2 structurally similar protozoans are antigenically different.

The prevalence of antibodies to Toxoplasma gondii was determined in sera from 105 domestic cats from Durango City, Mexico. Using a modified agglutination test, antibodies to this parasite were found in 21% of the 105 cats, with titers of 1:25 in 3 cats, 1:50 in 4 cats, 1:200 in 5 cats, 1:400 in 2 cats, 1:800 in 2 cats, 1:1,600 in 4 cats, and 1:3,200 or higher in 2 cats. Cats older than 1 yr had a significantly higher frequency of infection than that found in cats younger than 0.5 yr (41 vs. 13.2%, respectively; odds ratio = 4.55; 95% CI = 1.24-17.18; P = 0.01). Overall, the seroprevalence of T. gondii antibodies in cats in Durango, Mexico, is much lower compared with those reported in other countries.

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Resumen. Se describe una especie nueva de Pleseobyrsa, P. persea n. sp. de Costa Rica, cuya planta huésped es Persea americana P. Mill., siendo ésta la segunda especie del género conocida del país y la tercera cuya planta huésped es P. americana (aguacate). Se describen tanto el adulto como el estadio ninfal V; se agrega una clave modificada de Froeschner para las especies, y se ilustran ejemplares en el campo, el quinto estadio ninfal, adulto y los principales caracteres.

En Costa Rica, la producción de hortalizas se ha intensificado en las últimas décadas por el uso de paquetes tecnológicos (fertilizantes y plaguicidas sintéticos) en monocultivos. Este modelo ha sostenido la producción en Zarcero, cantón que provee productos vegetales al Valle Central. Sin embargo, estudios realizados por el Instituto Regional de Estudios en Sustancias Tóxicas (IRET) han revelado resultados preocupantes sobre el uso de plaguicidas y sus efectos negativos en el ambiente y en la salud de las personas. Como respuesta a esta problemática se inició en el 2018 un proyecto con la participación del IRET, de la Escuela de Ciencias Agrarias y de la División de Educación Rural, cuyo objetivo es “promover un modelo alternativo en la producción agrícola mediante trabajo colaborativo, diálogo de saberes y la construcción social del conocimiento para disminuir el uso de agroquímicos en Zarcero, Alajuela”.En el proyecto se han desarrollado actividades con 1) equipo académico nacional e internacional, 2) personas agricultoras y sus familias, 3) escolares. El primer paso del proyecto ha consistido en la conformación de un equipo donde sus integrantes desarrollen: a) un marco teórico-político de referencia común, b) una mirada interdisciplinaria para analizar-trabajar-transformar la realidad y c) un tejido afectivo para favorecer entendimientos y desde ahí mancomunar metas. Para lograrlo, se han realizado: a) círculos de estudio, b) trabajo de campo, c) intercambio de saberes en el ámbito nacional e internacional, d) producción educativa agrícola modular y e) la articulación con la docencia, la investigación y la producción. Además, se ha posicionado la agroecología en las agendas políticas institucional, local, regional y nacional y en algunos territorios internacionales del continente.Desde el trabajo académico tejido en el proyecto se ha aprendido a ser y a hacer “universidad necesaria”, ya que las universidades requieren legitimarse en el país, por lo que se ha propuesto, para recuperar la confianza de las personas agricultoras y sus familias, gestar espacios de acercamiento para contextualizar conjuntamente y reflexionar sobre la problemática agrícola, revitalizar saberes locales y obtener insumos para la escritura de documentos educativos con enfoque sociocrítico desde la educación popular.

Twelve Metarhizium isolates from Costa Rica, two from Honduras and one from Nicaragua were characterised using molecular and morphological information. Two gene sequences, TEF1-α and β-TUB, identified isolates as M. anisopliae, M. brunneum and M. robertsii, and has provided new sequence information. Eleven SSRs revealed fourteen different genotypes. Morphological variability coincided with allelic diversity within species. This work provides a starting point for the application of integral biocontrol programmes, but more comprehensive and detailed surveys are warranted to understand the species composition and genetic diversity of the Metarhizium in Central America.