Abstract INTRODUCTION: Triatomine bugs are vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. METHODS: Triatomine bugs were collected and identified following established protocols. In addition, infection with T. cruzi was detected by microscopic and molecular analysis. RESULTS: We captured an adult male specimen of the Eratyrus cuspidatus species that has not been reported in the state of Campeche. CONCLUSIONS: This finding provides new information on the distribution of E. cuspidatus in Mexico. However, more studies are needed to determine their epidemiological significance.

Abstract Murine typhus is a flea-borne disease caused by Rickettsia typhi, which was first detected in Mexico in 1927. It was not until 1996 that the first systematized study involving this pathogen was conducted in two coastal states of Mexico. We now report the first confirmed case of murine typhus in the state of Campeche, which occurred in a male patient who exhibited fever, thrombocytopenia, hyperbilirubinemia, and a rash. Furthermore, the patient reported having had previous contact with Rickettsia reservoirs.

Among the infectious diseases characterized by a febrile picture are: dengue, leptospirosis, rickettsiosis and salmonellosis, among others. The objective of this study was to identify IgM antibodies against dengue and Leptospira in febrile patientes. The seropositivity for IgM antibodies to dengue was 34%; 26.3% for women and 7.6% for men, without differences significant (p = 0.181). The seropositivity for IgM antibodies to Leptospira was 3.2%, being found only in women. Positive serology for both dengue and Leptospira was 1%. The serovars detected were Pomona and Canicola by the microagglutination technique. It was possible to identify the unsuspected presence of leptospirosis and dengue in atypical months for the latter, an important fact to consider the study of serology in the differential diagnosis of febrile diseases.

Resumen Entre las enfermedades infecciosas febriles se encuentran: dengue, leptospirosis, rickettsiosis y salmonelosis, entre otras. El objetivo de este estudio fue detectar la presencia de anticuerpos IgM a dengue y Leptospira en pacientes febriles. La seropositividad para IgM frente al dengue fue 34%; 26,3% en mujeres y 7,6% en varones, sin diferencias significativas (p = 0,181). La seropositividad para los anticuerpos IgM a Leptospira fue 3,2%; encontrándose sólo en mujeres. La serología positiva para leptospirosis y dengue fue 1%. Los serovares detectados fueron Pomona y Canicola por la técnica de microaglutinación. Se pudo identificar la presencia insospechada de leptospirosis y dengue en meses atípicos para este último, hecho importante para considerar el estudio de serología en el diagnóstico diferencial de enfermedades febriles.

ABSTRACT: The aim of this study was to identify the infection prevalence of Trypanosoma cruzi in opossums and triatomines captured in urban areas of Campeche City, Mexico. We collected 25 specimens of marsupials of Virginia opossums (Didelphis virginiana) species showing a T. cruzi infection prevalence of 52% (13/25). Also, 36 specimens of Pic (Triatoma dimiata) vectors were collected, showing a T. cruzi infection prevalence of 41.6% (15/36). All T. cruzi isolates were TcI, which correspond to the predominant lineage in mammals of Mexico, irrespective of the mammalian host species or vector.

RESUMEN: El objetivo del estudio fue identificar la prevalencia de infección con Trypanosoma cruzi en zarigüeyas (Didelphis virginiana) y Pic (Triatoma dimidiata) capturados en áreas urbanas de la ciudad de Campeche, México. Se colectaron 25 zarigüeyas con una prevalencia de infección con T. cruzi del 52% (13/25). También se colectaron 36 vectores de Pic con una prevalencia de infección del 41,6% (15/36) con T. cruzi. Todos los aislados de T. cruzi fueron TcI de acuerdo con la predominancia de este linaje en México independientemente del huésped mamífero o vector.

Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. The survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. Nine Leptospira interrogans serovars were tested by the microagglutination test. Reactivity was 21.3 % (69/323), 17.2 % corresponded to household dogs and 26.7 % to stray dogs. Leptospira Canicola (29 %), Leptospira Hardjo (22.58 %), and Leptospira Icterohaemorrhagiae (16.12 %) were the most common serovars reacting against the serum of household animals, while Leptospira Canicola (15.78 %), Leptospira Icterohaemorrhagiae (13.15 %), and Leptospira Pomona (7.89 %) were those reacting in stray dogs. Results showed that all dogs have been in contact with different Leptospira serovars and outdoor exposure is the main infection risk factor.

BACKGROUND: at present, dengue is an arbovirosis that is greatly affecting the Latin American countries, and Mexico is not the exception, where a hypoendemic region has evolved into a hyperendemic area because of the circulation of multiple serotypes. OBJECTIVES: to determine the seroprevalence of dengue virus in Campeche state, Mexico, and to identify the circulating serotypes in its various municipalities. METHODS: inhibition ELISA and plate reduction neutralizing test were the methods used in this study. RESULTS: of 600 samples, 67.5 % (405) had IgG antibodies to dengue virus whereas 32.5 % (195) were negative. Regarding the serotypes, 32.3 % had primary infection with serotype DEN-1 and 68 % showed secondary infection; the prevailing sequence was DEN-1/DEN-2 and DEN-3/DEN-4 in 9 municipalities. The infection with the 4 serotypes was mostly found in the 21-30 y age group. The most circulating serotype was DEN-1 throughout the state. CONCLUSIONS: seroprevalence and frequency of secondary infection observed in children and adults indicated an increased circulation of virus in the state and this was considered an important epidemiological factor for the emergence of outbreaks and the most severe forms of the disease.

INTRODUCCIÓN: el dengue en la actualidad es una arbovirosis que está impactando a los países latinoamericanos, y México no ha sido la excepción, donde de ser una región hipoendémica ha evolucionado a hiperendémica por la múltiple circulación de los serotipos. OBJETIVOS: determinar la seroprevalencia de los virus del dengue en el Estado de Campeche, México e identificar los serotipos circulantes en los diferentes municipios que conforman el estado. MÉTODOS: para este estudio se emplearon los métodos de ELISA de inhibición y la prueba de neutralización por reducción del número de placas. RESULTADOS: de un total de 600 muestras obtenidas, 67,5 % (405) presentó anticuerpos IgG contra virus dengue y 32,5 % (195) resultó negativo. Con respecto a los serotipos se detectó que 32,3 % tuvo una infección primaria con predominio del serotipo DEN-1 y 68 % infección secundaria; prevaleció la secuencia DEN-1/ DEN-2 y DEN-3/ DEN-4 en 9 municipios. El grupo de edad en el que fue más frecuente la infección a los 4 serotipos resultó el de 21 a 30 años. El serotipo que resultó con mayor circulación en el estado fue DEN-1. CONCLUSIONES: la seroprevalencia y la frecuencia de infección secundaria observada en niños y adultos, indica la elevada circulación de los virus en el Estado; este resultó un factor epidemiológico importante para la aparición de brotes epidémicos y de las formas graves de la enfermedad.