Neosporosis in Argentina: Past, present and future perspectives.

Neosporosis, caused by the protozoan Neospora caninum, was first diagnosed in Argentinean cattle in the 90's. With a national bovine stock of approximately 53 million head, the cattle industry is socially and economically relevant. Severe economic losses have been estimated at US$ 33 and 12 million annually in dairy and beef cattle, respectively. Approximately 9% of bovine abortions in the Buenos Aires province are caused by N. caninum. In 2001, the first isolation of N. caninum oocysts from feces of a naturally infected dog was performed in Argentina and named as NC-6 Argentina. Further strains were isolated from cattle (NC-Argentina LP1, NC-Argentina LP2) and axis deer (Axis axis, NC-Axis). Epidemiological studies revealed a high distribution of Neospora-infections not only in dairy but also in beef cattle, with seroprevalence rates of 16.6-88.8% and 0-73%, respectively. Several experimental infection studies in cattle have been carried out, as well as attempts to develop effective vaccines to avoid Neospora-abortions and transmission. However, no vaccine has proven successful for its use in daily practice. Reduction of seroprevalence, vertical transmission and Neospora-related abortions have been achieved in dairy farms by the use of selective breeding strategies and embryo transfer. Neospora-infections have been also detected in goats, sheep, deer, water buffaloes (Bubalus bubalis) and gray foxes (Lycalopex griseus). Moreover, Neospora-related reproductive losses were reported in small ruminants and deer species and could be more frequent than previously thought. Even though diagnostic methods have been improved during the last decades, control of neosporosis is still not optimal. The development of new strategies including new antiprotozoal drugs and vaccines is highly needed. This paper reviews the information from the previous 28 years of research of N. caninum in Argentina, including seroprevalence and epidemiological studies, available diagnostic techniques, experimental reproduction, immunization strategies, isolations and control measures in domestic and non-domestic animals from Argentina.

Delayed-type hypersensitivity skin test against Neospora caninum in heifers with undetectable specific antibodies.

Delayed-type hypersensitivity (DTH) has been used in human and veterinary medicine as a skin testing for evaluating in vivo cell-mediated immune responses (CMIR). Whereas CMIR is a key process to control intracellular pathogens, its value at identifying cattle exposed to the abortigenic intracellular coccidian parasite Neospora caninum is unknown. In this work, we have evaluated a DTH skin testing in cattle exposed to N. caninum and still seronegative. Female calves were experimentally sensitized by subcutaneous (SC) inoculation with live tachyzoites of N. caninum (NC-Argentina LP1) in sterile phosphate-buffered saline (PBS) (group A; n: 8) whereas other calveswere mock-sensitized with PBS (group B; n: 6). Two DTH skin tests were performed by intradermal inoculation with a soluble lysate of N. caninum tachyzoites (NC-Argentina LP1) in the neck region at 60d and 960 d after sensitization. Skinfold thickness at the intradermal inoculation site was measured at 0, 24, 48 h post each DTH skin test and skin biopsies taken for microscopic evaluation. Specific N. caninum antibodies kinetics was evaluated all throughthe experiment. We found that whereas N. caninum specific antibodies remained below the ELISA cut-off, a distinctive skinfold thickness increase was detected in sensitized animals (group A) at the DTH skin test site, showing induration, swelling and inflammatory infiltration. Mock sensitized animals (group B) showed no skinfold thickness growth and lacked specific antibody response. Thus, N. caninum DTH skin testing could be a useful diagnostic tool for the detection of CMIR during N. caninum infection in non-humoral responders.

Factors associated with pregnancy desire among adolescent women in five Latin American countries: a multilevel analysis.

OBJECTIVE: To explore demographic, socio-economic, and reproductive factors associated with pregnancy desire among adolescents in five Latin American countries. DESIGN: Secondary analysis using nationally representative, cross-sectional data from UNICEF Multiple Indicator Cluster Surveys (MICS). SETTING: Cuba, the Dominican Republic, El Salvador, Mexico, and Panama. POPULATION: Adolescents 15-19 years old who were pregnant or mothers (n = 4207). METHODS: Chi-square tests, simple linear regressions, and multilevel Poisson regression models were used to estimate associations between individual- and country-level factors associated with pregnancy desire among adolescents. MAIN OUTCOME MEASURES: Desire for pregnancy among adolescents who were pregnant or had given birth in the last 2 years. RESULTS: The proportion of adolescents who reported they desired their last pregnancy ranged from 79.3% in Cuba to 37.6% in Panama; approximately half the adolescents in Mexico, El Salvador, and the Dominican Republic desired their last pregnancy. The multilevel analysis shows that pregnancy desire was more likely among adolescent women who were less educated [prevalence ratio (PR) = 0.97, 95% confidence interval (CI) 0.96-0.98], older (PR = 1.39, 95% CI 1.04-1.09), married or cohabiting with a partner (PR = 0.70, 95% CI 0.53-0.93), and had low parity (PR = 0.67, 95% CI 0.58-0.76). CONCLUSIONS: Adolescents with less education, who are older, married or cohabiting, and with low parity were more likely to desire their pregnancy. These data constitute evidence that, in conjunction with qualitative and implementation research, can be used to better design services for adolescents so they can exercise their sexual and reproductive rights, and plan healthier and more satisfying futures. FUNDING: All the databases used on the performance of this study are open access. We did not receive any funding for the present analysis. TWEETABLE ABSTRACT: Parity and marital status showed the strongest association with adolescent pregnancy desire in five Latin American countries.

Factors associated with ever use of mammography in a limited resource setting. A mixed methods study.

OBJECTIVE: To evaluate facilitators and barriers influencing mammography screening participation among women. DESIGN: Mixed methods study. SETTING: Three hospital catchment areas in Hidalgo, Mexico. PARTICIPANTS: Four hundred and fifty-five women aged 40-69 years. INTERVENTION: Three hundred and eighty women completed a survey about knowledge, beliefs and perceptions about breast cancer screening, and 75 women participated in semi-structured, in-person interviews. Survey data were analyzed using logistic regression; semi-structured interviews were transcribed and analyzed using elements of the grounded theory method. MAIN OUTCOME MEASURE: Women were categorized as never having had mammography or having had at least one mammogram in the past. RESULTS: From survey data, having had a Pap in the past year was associated with ever having had breast screening (odds ratio = 2.15; 95% confidence interval 1.30-3.54). Compared with never-screened women, ever-screened women had better knowledge of Mexican recommendations for the frequency of mammography screening (49.5% vs 31.7% P < 0.001). A higher percentage of never-screened women perceived that a mammography was a painful procedure (44.5% vs 33.8%; P < 0.001) and feared receiving bad news (38.4% vs 22.2%; P < 0.001) compared with ever-screened women. Women who participated in semi-structured, in-person interviews expressed a lack of knowledge about Mexican standard mammographic screening recommendations for age for starting mammography and its recommended frequency. Women insured under the 'Opportunities' health insurance program said that they are referred to receive Pap tests and mammography. CONCLUSIONS: Local strategies to reduce mammogram-related pain and fear of bad news should work in tandem with national programs to increase access to screening.

Plant-based chimeric HPV-virus-like particles bearing amyloid-ß epitopes elicit antibodies able to recognize amyloid plaques in APP-tg mouse and Alzheimer's disease brains.

The main amyloid-beta (Aß) variants detected in the human brain are full-length Aß1-40 and Aß1-42 peptides; however, a significant proportion of AD brain Aß consists also of N-terminal truncated/modified species. The majority of the previous immunotherapeutic strategies targeted the N-terminal immunodominant epitope of the full-length Aß; however, most of the pathological N-truncated forms of Aß lack this critical B cell epitope. Recently, virus-like particles (VLPs), self-assembled structures with highly ordered repetitive patterns on their surface and capable of inducing robust immune responses, were applied as a promising platform for various antigen expressions. In this study, we expressed in plants two chimeric HPV16 L1 capsid proteins obtained by introduction of the ß-amyloid 11-28 epitope (Aß 11-28) into the h4 helix or into the coil regions of the L1 protein. The Aß 11-28 epitope was chosen because it is present in the full-length Aß 1-42 as well as in the truncated/modified amyloid peptide species. After expression, we assembled the chimerical L1/Aß 11-28 into a VLP in which the Aß 11-28 epitope is exposed at very high density (360 times) on the surface of the VLP. The chimeric VLPs elicited in mice Aß-specific antibodies binding to ß-amyloid plaques in APP-tg mouse and AD brains. Our study is the first to demonstrate a successful production in plants and immunogenic properties in mice of chimeric HPV16 L1 VLPs bearing Aß epitope that may be of potential relevance for the development of multivalent vaccines for a multifactorial disease such as AD.

Anti-Neospora caninum and anti-Sarcocystis spp. specific antibodies cross-react with Besnoitia besnoiti and influence the serological diagnosis of bovine besnoitiosis.

Bovine besnoitiosis control remains a challenge because the disease continues to spread and control relies solely on accurate diagnosis coupled to management measures. However, recent studies have reported that routinely used ELISAs may raise a high number of false-positive results. Herein, cross-reactions between Besnoitia besnoiti antigens and anti-Neospora caninum and/or anti-Sarcocystis spp.-specific antibodies were studied in an in house ELISA since N. caninum and Sarcocystis spp. are closely related parasites, and both infections are highly prevalent in cattle worldwide. The serum panel was composed of the following categories: sera from B. besnoiti-seronegative (n=75) and -seropositive cattle (n=66), B. besnoiti-based-ELISA false-positive reactors (n=96) together with N. caninum (n=36) and Sarcocystis spp. (n=42) -seropositive reference cattle sera. B. besnoiti tachyzoite based western blot (WB) results classified animals as seropositive or seronegative. Sera were analyzed for the detection of anti-N. caninum by WB and ELISA and anti-Sarcocystis spp.-specific antibodies by WB and IFAT. Those samples recognizing a Sarcocystis spp. 18-20 kDa antigenic region and N. caninum 17-18 kDa immunodominant antigen were considered to be Sarcocystis spp. and N. caninum seropositive, respectively. The category of B. besnoiti based-ELISA false-positive reactors showed the highest number of sera with specific anti-Sarcocystis spp. and anti-N. caninum antibodies (74%; 71/96), followed by the N. caninum-seropositive cattle category (52.8%; 19/36). In contrast, few B. besnoiti-seronegative and -seropositive cattle showed antibodies against Sarcocystis spp. and N. caninum (10.7%; 8/75 and 1.5%; 1/66), respectively). This study revealed that B. besnoiti false-positive ELISA results were associated not only with the presence of anti-N. caninum and anti-Sarcocystis spp. antibodies (χ(2): 78.36; p<0.0001; OR: 34.6; CI: 14-88) but also with high antibody levels against them using ELISA and IFAT tests, respectively (p<0.05; t-test). These results may explain why only some animals seropositive to Sarcocystis spp. and/or N. caninum are Besnoitia false-positive reactors. Therefore, sera meeting these requirements should be included in future validations of serological tests for bovine besnoitiosis.

Isolation and molecular characterization of a new Neospora caninum isolate from cattle in Argentina.

Neospora caninum is one of the most important causes of bovine abortion, but isolation of live parasites from infected tissue is difficult. The aims of the present study were to obtain new isolates of N. caninum from congenitally infected asymptomatic newborn cattle in Argentina and to perform characterization by multilocus-microsatellite analysis. Five clinically normal born calves, with demonstrable N. caninum antibodies in precolostrum serum by indirect fluorescent antibody test, were euthanized and their brain samples were processed for histopathological, immunohistochemical, polymerase chain reaction (PCR) analysis, and for bioassay in γ-interferon knockout (GKO) mice. Although N. caninum DNA was detected in brain from all the calves by PCR, viable N. caninum was isolated in GKO mice from only one calf. Neospora caninum tachyzoites of this Argentinean isolate, designated NC-Argentina LP1, were propagated in VERO cell cultures seeded with tachyzoites from the infected GKO mice tissues. Multilocus-microsatellite typing on DNA derived from cell cultured tachyzoites revealed a unique genetic pattern, different from reported isolates. This is the first bovine isolation and genetic characterization of N. caninum in Argentina.

Neospora caninum NC-6 Argentina induces fetopathy in both serologically positive and negative experimentally inoculated pregnant dams.

Neospora caninum infection is a major cause of abortion in cattle. The objectives of this study were to genetically characterize the N. caninum NC-6 Argentina isolate using a multilocus microsatellite analysis approach and to study its biological behavior by experimental inoculations into seronegative and seropositive pregnant cattle, evaluating the humoral and cellular immune response elicited and the occurrence of transplacental transmission and fetopathy. Pregnant cows (65 days of gestation) seropositive and seronegative to N. caninum were intravenously inoculated with tachyzoites of the NC-6 Argentina N. caninum strain and slaughtered at 108 ± 2 days of gestation. Serum samples were analyzed for N. caninum antibodies by indirect fluorescent antibody test. The cellular immune response was analyzed by detection of gamma interferon (γIFN) production in blood cells. Tissue samples from dams, fetuses, and placental cotyledons were processed by histopathological and immunohistochemical techniques and examined for N. caninum DNA by PCR. Positive DNA samples were further analyzed by multilocus microsatellite typing for N. caninum. Inoculated animals had significantly higher N. caninum antibody titers and γIFN production than control animals. One seropositive inoculated cow aborted, one seronegative cow had a non-viable fetus, and the remaining fetuses from the experimentally inoculated dams had histopathologic lesions. The PCR was positive in 3/4 fetuses from seronegative inoculated cows and in 2/3 fetuses from seropositive inoculated cows. Multilocus microsatellite analysis revealed that the N. caninum DNA present in fetuses and placentas had an identical pattern to NC-6 Argentina strain. The NC-6 Argentina strain proved to be able to cross the placenta and to induce fetopathy in both the seropositive and seronegative dams.

Detection of HP10 antigen in serum for diagnosis and follow-up of subarachnoidal and intraventricular human neurocysticercosis.

INTRODUCTION: Neurocysticercosis (NC), a parasitic disease caused by Taenia solium, may be either asymptomatic or show a mild to severe clinical picture with intracranial hypertension. The most severe form of the disease is caused when viable cysticerci are localised in the ventricles or in subarachnoidal cisterns at the base of the skull. Detection of the secreted metacestode antigen HP10 in cerebrospinal fluid is a sensitive and specific method for the diagnosis of these severe NC cases. OBJECTIVE AND METHODS: To evaluate the validity of HP10 antigen detection ELISA when applied to serum, using paired serum and cerebrospinal fluid samples from 116 radiologically and clinically characterised NC patients. RESULTS: The HP10 antigen assay exhibited a similarly high sensitivity in identifying severe NC cases from sera (84.8%) and CSF (91.3%). In contrast, HP10 antigen was rarely detected in asymptomatic or mild NC cases (3 of 57). Importantly, the HP10 antigen assay applied to serum showed high specificity (94%) when used in 126 serum samples of non-NC subjects from an endemic community with a confirmed coproparasitological diagnosis of intestinal parasitic infections. Finally, the HP10 assay also proved to be of value in the follow-up of treated patients. CONCLUSION: This study confirms that detection of the metacestode HP10 antigen in serum is a useful tool for diagnosis and follow-up of patients with severe forms of NC treated with cysticidal drugs.

A study on maternal mortality in Mexico through a qualitative approach.

This report presents the main qualitative results of a verbal autopsy study carried out in three states of Mexico, which aimed at identifying the factors associated with maternal mortality that could be subject to modifications through concrete interventions. By reviewing death certificates issued in 1995, it was possible to identify 164 households where a maternal death had occurred. One hundred forty-five of these households were visited, and a precoded questionnaire was completed to explore socioeconomic and living conditions, as well as causes of death. An open-ended question to prompt the relatives to narrate all the facts that led to the maternal deaths was included in the questionnaire. This study presents an analysis of that question, focusing on the delays in the care-seeking process and organized according to the model of the three delays: in deciding to seek care, in reaching a care facility, and in actually receiving care after arrival. Additionally, problems related to quality of care are examined. For analysis of the accounts, structural, interactional/community, and subjective variables were identified that allowed refining of our understanding of the problem of maternal deaths. Finally, based on the findings of the study, this article presents a series of recommendations, highlighting that interventions should address the early stages of a complication and focus on decreasing the various forms of inequality (gender and socioeconomic) associated with the occurrence of maternal deaths.

[Acceptability of food supplements in pregnant or lactating women and children under 5 years of age]. / Aceptabilidad a suplementos nutricios en mujeres embarazadas o lactando y niños menores de cinco años.

OBJECTIVE: The present study explores the acceptance and consumption of nutritional supplements that form part of a governmental program to support nutritionally vulnerable groups. MATERIAL AND METHODS: Pregnant and lactating women, and mothers of malnourished toddlers, infants and children were interviewed. Data were collected, after introduction with an interview guide with an open-ended format, through face-to-face interviews conducted at home. Interviews were taped with previous informed consent. Analysis included topics and subtopics approached by the interviewed women. RESULTS: The studied population showed good acceptance to the supplement when offered as a drink. When considering benefits, pregnant women thought first of their baby's health than of their own and associated the possible advantages of the supplement to its "vitamin" contents. Acceptance of the flavors was largely influenced by previous contact to specific flavors. Children under 1 year of age preferred the liquid consistency and elderly children favored the puree. Most mothers considered that the offered amount was enough and there was the general impression that, as the time of the intervention elapsed, children showed greater appetite. The diet was not substituted by the supplement. CONCLUSIONS: Acceptance of the supplement may be improved by messages focusing on the well-being and health of the child and insisting on the benefits for the pregnant mother. Community health providers should be involved in supporting the program, recommending consumption and acceptance of the supplement. The identification by mothers of "vitamins" as part of the supplement may be used to reinforce the concept of beneficial effects associated to micronutrient supplementation. Qualitative evaluations should be performed as part of the assessment of community-based programs.

Effects of psychosocial support during labour and childbirth on breastfeeding, medical interventions, and mothers' wellbeing in a Mexican public hospital: a randomised clinical trial.

OBJECT: To evaluate the effects of psychosocial support during labour, delivery and the immediate postpartum period provided by a female companion (doula). DESIGN: The effects of the intervention were assessed by means of a randomised clinical trial. Social support by a doula was provided to women in the intervention group, while women in the control arm received routine care. SETTING: A large social security hospital in Mexico City. PARTICIPANTS: Seven hundred and twenty-four women with a single fetus, no previous vaginal delivery, < 6 cm of cervical dilatation, and no indications for an elective caesarean section were randomly assigned to be accompanied by a doula, or to receive routine care. OUTCOME MEASURES: Breastfeeding practices, duration of labour, medical interventions, mother's emotional conditions, and newborn's health. METHODS: Blinded interviewers obtained data from the clinical records, during encounters with women in the immediate postpartum period, and at their homes 40 days after birth. Relative risks and confidence intervals were estimated for all relevant outcomes. RESULTS: The frequency of exclusive breastfeeding one month after birth was significantly higher in the intervention group (RR 1.64; I-C: 1.01-2.64), as were the behaviours that promote breastfeeding. However, the programme did not achieve a significant effect on full breastfeeding. More women in the intervention group perceived a high degree of control over the delivery experience, and the duration of labour was shorter than in the control group (4.56 hours vs 5.58 hours; RR 1.07 CI (95%) = 1.52 to -0.51). There were no effects either on medical interventions, mothers' anxiety, self-esteem, perception of pain and satisfaction, or in newborns' conditions. CONCLUSIONS: Psychosocial support by doulas had a positive effect on breastfeeding and duration of labour. It had a more limited impact on medical interventions, perhaps because of the strict routine in hospital procedures, the cultural background of the women, the short duration of the intervention, and the profile of the doulas. It is important to include psychosocial support as a component of breastfeeding promotion strategies.

PIP: Studies in numerous countries have documented the positive contributions of doulas--women experienced in childbirth who provide continuous physical, emotional, and informational support to women before, during, and just after childbirth. The present study, conducted in a Mexican Institute of Social Security public hospital, explored the hypothesis that psychosocial support from a doula increases exclusive and full breast feeding by improving the mother's emotional status, shortening the duration of labor, and decreasing medical intervention. 724 women with no previous vaginal delivery and no indications for cesarean section delivery were randomly assigned to be accompanied by a doula (n = 361) or to receive routine care (n = 363). Blinded interviewers obtained outcome data from the clinical records, encounters with mothers in the immediate postpartum period, and home visits 40 days after delivery. The frequency of exclusive breast feeding 1 month after birth was significantly higher in the intervention group than the control group (12% vs. 7%; relative risk (RR), 1.64; 95% confidence interval (CI), 1.01-2.64). However, the program did not achieve a significant effect on full breast feeding (37% and 36%, respectively). The duration of labor was shorter in the intervention group than the control group (4.56 vs. 5.58 hours; RR, 1.07; 95% CI, -1.52-0.51). A significantly larger proportion of women in the intervention group than the control group perceived a high level of control over labor (79.8% vs. 77.1%; RR, 1.14; 95% CI, 1.03-1.27). There were no effects on medical interventions, maternal anxiety, self-esteem, perception of pain, maternal satisfaction, or newborn Apgar scores. Although the prevalence of exclusive breast feeding was low in both groups, these findings suggest that psychosocial support during labor and the immediate postpartum period should be part of a comprehensive strategy to promote breast feeding.

"Alone, I wouldn't have known what to do": a qualitative study on social support during labor and delivery in Mexico.

This article presents some of the most relevant qualitative results of a trial to evaluate the effects of the provision of psychosocial support to first-time mothers during labor, childbirth and in the immediate postpartum period in a social security hospital in Mexico City. The article focuses on the experiences of mothers who have received psychosocial support from a doula (the term doula is used to identify a woman who provides continuous support to a woman during labor. delivery and the immediate postpartum period) and compares them with the experiences of those women who gave birth following normal hospital routine. Sixteen in-depth interviews were held with women in the immediate post partum period (eight of whom had been accompanied by a doula and eight who had not) before they were discharged from hospital, and the results were analyzed using qualitative techniques. The interviews showed that the women accompanied by a doula had a more positive childbirth experience. The differences between both groups related to their perceptions of the childbirth experience; the treatment they received from hospital staff; the information they were given and how well they understood it; their perception of hospital routines; their feelings about cesarean sections and, spatial and temporal perceptions. The most important difference between the two groups was the way they expressed their feelings about their own labor, their sense of control and their self-perception.

[Research on social support in health: current status and new challenges]. / La investigación sobre apoyo social en salud: situación actual y nuevos desafíos.

On the borderline between sociology and psychology, the concept of social support has made it possible to develop a whole research tradition aimed at explaining some of the differences existing in the distribution of mental and physical disease. The concept of social support itself, however, still presents some ambiguities which must be clarified. These problems are discussed and it is showed and shows that the topic can be enriched with the contribution of the social sciences. Different definitions of the concept itself, are briefly analysed and the complexity and multidimensional character of social support are highlighted. The association between social support and health is discussed. The differences and implications of the direct effect model and the buffering effect model are addressed, and the relevance of the construct of social support is enhanced. The need to study social support not only as a likely determinant of some forms of disease, but also as a dependent variable, is brought out. Some recent developments in the study of factors associated with the availability of social support are discussed. It is shown that social support is a product of certain social factors which can be clearly identified by sociological analysis. In order to illustrate this point, the structural determinants of a specific dimension of social support-attention-are discussed. The importance of structural variables like social class and gender in attempting to explain the differential distribution of certain forms of social support is emphasized. It is proposed, on the theoretical level, that the intersection between two related autonomous constructs-social class and social support-may better explain those aspects of these concepts that are of importance to observed heterogeneity in the distribution of mental and physical health. Different theoretical and methodological approaches to the understanding of the determinants of social support and its effect on health are suggested.