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The Echinococcus granulosus is the agent that causes the classical hydatidosis or cystic echinococcosis. The most enlarged cycle in South America is the sheep-dog cycle, it offers excellent conditions for the development of the parasite. The province of La Pampa shows an endemic presence with notification of human cases and infected dogs. The distribution and prevalence of the disease in the Department of Maracó, La Pampa , Argentina was evaluated during the years 1996 and 1997.Dogs of 36 fanns that had ovines, were dosed with arecoline hydrobromide at doses of 3.5 mg/kg , the result obtained was that 75% were positive to Tennia spp. and 8% to Echinococcus granulosus. In total 137 dogs were evaluated , being from 3 to 4 per fann, from wich 58% were positive to Tennia spp. and 2,6% to Echinococcus granulosus. Infonnation from 187.790 slaughtered cattle was obtained between the years 1996 and 1997 in two slaughterhouses in the province of La Pampa. Analysis from the clinical records indicated 11 human cases that appeared during the period 96/97 (annual incidence rate of 6.79 x 100.000 inhabitants). As a concequence, it is of sanitary nterest to enlarge the investigations in other districts of the province of La Pampa with the aim of delimiting the endemic distribution area within the province, and also organising epidemiologic watchfulness systems of the illnes

Contamination of urban environ­ments with dog feces implies a problem for public and animal health. The objective was to determine the presence of zoonotic nematode in the public spaces of the area of the Brown Health Center (General Pico, La Pampa). Sam­ples of feces and ground in public spaces were collected. Parasitological analysis´ were made. Results are presented in the samples taken in 2013 and 2014. In May 2013, 169 samples of feces were collected, 85 of them proved positive (50,3%) and 33 samples (19,5%) multi-para­sites. In September, 198 samples were taken; 104 proved positive (52,5%) and 37 (18,6%) multi-parasite. In May 2014, 177 feces sam­ples were collected, 70 (39,5%) proved positive and 34 (19,2%) multi-parasite. In October 241 were taken; 139 proved positive (57,7%) and 90 (37,3%) multiparasitadas. Predominant species in the study period were Ancylostoma sp. fol­lowed by Trichuris sp. In May 2013, 105 sam­ples were taken, 40 (3,1 %) proved positive. In September, 45 samples were collected, 48 (52, 2%) proved positive. In May 2014, 92 ground samples were taken, 48 (52,2%) proved posi­tive. In October were collected 115, 49 (42,6%). proved positive. The main parasite found was Ancylostoma sp. It can be concluded that public spaces, given the parasite amount found, rep­resent a threat to public health, especially for children. Due to their ground interaction, playing habits and their behavior, they are the most vul­nerable population to parasites. Implementation of information, communication and education strategies is needed for health insurance from an inter-disciplinary work perspective

BACKGROUND:Cystic echinococcosis (CE) is an important zoonotic disease caused by the cestode parasite Echinococcus granulosus. It occurs in many parts of the world where pastoral activities predominate, including the Rio Negro province of Argentina. Although CE control activities have been undertaken in the western regions of Rio Negro for more than two decades, the disease continues to remain prevalent in both the human and livestock animal populations. Vaccination of animal intermediate hosts of CE with the EG95 vaccine may provide a new opportunity to improve the effectiveness of CE control measures, although data are lacking about field application of the vaccine. AIMS:Evaluate the impact of EG95 vaccination in sheep on the transmission of Echinococcus granulosus in a field environment. METHODOLOGY:Two trial sites were established in western Rio Negro province within indigenous communities. Vaccination of lambs born into one trial site was introduced and continued for 6 years. Prior to initiation of the trial, and at the end of the trial, the prevalence of CE in sheep was determined by necropsy. Weaned lambs received two injections of EG95 vaccine, approximately one month apart, and a single booster injection one year later. Vaccination was not implemented at the second trial site. A total of 2725 animals were vaccinated in the first year. Animals from this cohort as well as age-matched sheep from the control area were evaluated by necropsy. KEY RESULTS:Introduction of the vaccine led to a statistically significant in the number and size of hydatid cysts in comparison to the situation prior to the introduction of the vaccine, or compared to CE prevalence in the control area where the vaccine was not applied. The prevalence of infection in the vaccinated area was also significantly reduced by 62% compared to the re-intervention level, being lower than the prevalence seen in the control area, although the difference from the control area after the intervention was not significant possibly due to limitations in the numbers of animals available for necropsy. CONCLUSIONS:Vaccination of sheep with the EG95 vaccine provides a valuable new tool which improves the effectiveness of CE control activities. Vaccination was effective even in a difficult, remote environment where only approximately half the lambs born into the communities were fully vaccinated.

There is little information on the humoral response of sheep experimentally infected with Echinococcus granulosus. Thus, the objective of this study was to evaluate this response and measure its evolution. Doses of 10, 100, 1000 and 10000 E. granulosus eggs were prepared and inoculated via intraruminal puncture. Blood samples were obtained before inoculation and every 48 h after inoculation, until they became seropositive. Thereafter, they were taken monthly for the first year and then every three months until 1700 days of observation had been completed. An ELISA test, with total hydatid fluid antigen, was used for immunodiagnosis. The average optical density of the 12 inoculated sheep was found to be above the mean cutoff value 10 days after inoculation, went on increasing until 180 days after inoculation and remained above the cutoff level until the end of the observation period. This confirms that the antibody response of sheep to E. granulosus infection occurs before production of hydatid fluid and that activation, mobilization and establishment of oncospheres in the tissues generates a persistent response from the host's immune system.