Taenia solium transmission in a rural community in Honduras : an examination of risk factors and knowledge

Taenia soliurn taeniasis and cysticercosis are recognized as a major public health problem in Latin America. T. soliurn transmission not only affects the health of the individual, but also social and economic development, perpetuating the cycle of poverty. To determine prevalence rates, population knowledge and risk factors associated with transmission, an epidemiological study was undertaken in the rural community of Jalaca. Two standardized questionnaires were used to collect epidemiological and T. soli urn general knowledge data. Kato-Katz technique and an immunoblot assay (EITB) were used to determine taeniasis and seroprevalence, respectively. In total, 139 individuals belonging to 56 households participated in the study. Household characteristics were consistent with conditions of poverty of rural Honduras: 21.4% had no toilet or latrines, 19.6% had earthen floor, and 51.8% lacked indoor tap water. Pigs were raised in 46.4% of households, of which 70% allowed their pigs roaming freely. A human seroprevalence rate of 18.7% and a taeniasis prevalence rate of 2.4% were found. Only four persons answered correctly 2: 6 out of ten T. soliurn knowledge questions, for an average passing score of 2.9%. In general, a serious gap exists in knowledge regarding how humans acquire the infections, especially neurocysticercosis was identified. After regression analysis, the ability to recognize adult tapeworms and awareness of the clinical importance of taeniasis, were found to be significant risk factors for T. soliurn seropositivity. These results demonstrate a high level of transmission and a low level of kn~,wledge about Taenia soliurn in Jalaca. Consequently, intervention measures integrated with health education are necessary to decrease the burden caused by this parasite.

Transmission of West Nile virus in the Niagara Region among a population at risk for exposure

Background. West Nile Virus (WNV), a mosquito-borne flavivirus, is one of an increasing number of infectious diseases that have been emerging or re-emerging in the last two decades. Since the arrival ofWNV to Canada to present date, the Niagara Region has only reported 30 clinical cases, a small number compared to the hundreds reported in other regions of similar conditions. Moreover, the last reported human case in Niagara was in 2006. As it has been demonstrated that the majority of WNV infections are asymptomatic, the question remains whether the lack of clinical cases in Niagara truly reflects the lack of transmission to humans or if infections are still occurring but are mostly asymptomatic. Objectives. The general objective of this study was to establish whether or not active WNV transmission could be detected in a human population residing in Niagara for the 2007 transmission season. To fullfil this objective, a cross-sectional seroprevalence study was designed to investigate for the presence of anti-WNV antibodies in a sample of Mexican migrant agricultural workers employed in farms registered with the Seasonal Agricultural Workers Program (SAWP). Due to the Mexican origin of the study participants, three specific research objectives were proposed: a) determine the seroprevalence ofanti-WNV antibodies as well as anti-Dengue virus antibodies (a closely related virus prevalent in Mexico and likely to confound WNV serology); b) analyze risk factors associated with WNV and Dengue virus seropositivity; and c) assess the awareness of study participants about WNV infection as well as their understanding of the mode of transmission and clinical importance of the infection. Methodology: After obtaining ethics clearance from Brock University, farms were visited and workers invited to participate. Due to time constraints, only a small number of farms were enrolled with a resulting convenience and non-randomized study sample. Workers' demographic and epidemiological data were collected using a standardized questionnaire and blood samples were drawn to determine serum anti-WNV and anti- Dengue antibodies with a commercial ELISA. All positive samples were sent to the National Microbiology Laboratory in Winnipeg, Manitoba for confirmation with the Plaque Reduction Neutralization Test (PRNT). Data was analyzed with Stata 10.0. Antibody determinations were reported as seroprevalence proportions for both WNV and Dengue. Logistic regression was used to analyze risk factors that may be associated with seropositivity and awareness was reported as a proportion of the number of individuals possessing awareness over the total number of participants. Results and Discussion. In total 92 participants working in 5 farms completed the study. Using the commercial ELISA, seropositivity was as follows: 2.2% for WNV IgM, 20.7% for WNV IgG, and 17.1 % for Dengue IgG. Possible cross-reactivity was demonstrated in 15/20 (75.0%) samples that were positive for both WNV IgG and Dengue IgG. Confirmatory testing with the PRNT demonstrated that none of the WNV ELISA positive samples had antibodies to WNV but 13 samples tested positive for anti-Dengue antibodies (14.1 % Dengue sereoprevalence). The findings showed that the ELISA performance was very poor for assessing anti-WNV antibodies in individuals previously exposed to Dengue virus. However, the ELISA had better sensitivity and specificity for assessing anti-Dengue antibodies. Whereas statistical analysis could not be done for WNV seropositivity, as all samples were PRNT negative, logistic regression demonstrated several risk factors for Dengue exposure_ The first year coming to Canada appeared to be significantly associated with increased exposure to Dengue while lower socio-economic housing and the presence of a water basin in the yard in Mexico appeared to be significantly associated with a decreased exposure to Dengue_ These seemingly contradictory results illustrate that in mobile populations such as migrant workers, risk factors for exposure to Dengue are not easily identified and more research is needed. Assessing the awareness of WNV and its clinical importance showed that only 23% of participants had some knowledge of WNV, of which 76% knew that the infection was mosquito-borne and 47% recognized fever as a symptom. The identified lack of understanding and awareness was not surprising since WNV is not a visible disease in Mexico. Since WNV persists in an enzootic cycle in Niagara and the occurrence of future outbreaks is unpredictable, the agricultural workers remain at risk for transmission. Therefore it important they receive sufficient health education regarding WNV before leaving Mexico and during their stay in Canada. Conclusions. Human transmission of WNV could not be proven among the study participants even when due to their occupation they are at high risk for mosquito bites. The limitations of the study sample do not permit generalizable conclusions, however, the study findings are consistent with the absence of clinical cases in the Niagara Region, so it is likely that human transmission is indeed neglible or absent. As evidenced by our WNV serology results, PRNT must be utilized as a confirmatory test since false positivity occurs frequently. This is especially true when previous exposure to Dengue virus is likely.

Closing the Summer Learning Gap for Vulnerable Children: An Examination of a Summer Family Literacy Program for Junior Kindergarten Children At-Risk for Reading Difficulties

The learning gap created by summer vacation creates a significant breach in the learning cycle, where student achievement levels decrease over the course ofthe summer (Cooper et aI., 2000). In a review of 39 studies, Cooper and colleagues (1996) specified that the summer learning shortfall equals at least one month loss of instruction as measured by grade level equivalents on standardized test scores. Specifically, the achievement gap has a more profound effect on children as they grow older, where there is a steady deterioration in knowledge and skills sustained during the summer months (Cooper et aI., 1996; Kerry & Davies, 1998). While some stakeholders believe that the benefits of a summer vacation overshadow the reversing effect on achievement, it is the impact of the summer learning gap on vulnerable children, including children who are disadvantaged as a result of requiring special educational needs, children from low socioeconomic backgrounds, and children learning English as a second language, that is most problematic. More specifically, research has demonstrated that it is children's literacy-based skills that are most affected during the summer months. Children from high socioeconomic backgrounds recurrently showed gains in reading achievement over the summer whereas disadvantaged children repeatedly illustrate having significant losses. Consequently, the summer learning gap was deemed to exaggerate the inequality experienced by children from low socioeconomic backgrounds. Ultimately, the summer learning gap was found to have the most profound on vulnerable children, placing these children at an increased chance for academic failure. A primary feature of this research project was to include primary caregivers as authentic partners in a summer family literacy program fabricated to scaffold their children's literacy-based needs. This feature led to the research team adapting and implementing a published study entitled, Learning Begins at Home (LBH): A Research-Based Family Literacy Program Curriculum. Researchers at the Ontario Institute designed this program for the Study of Education, University of Toronto. The LBH program capitalized on incorporating the flexibility required to make the program adaptable to meet the needs of each participating child and his or her primary caregiver. As it has been well documented in research, the role primary caregivers have in an intervention program are the most influential on a child's future literacy success or failure (Timmons, 2008). Subsequently, a requirement for participating in the summer family literacy program required the commitment of one child and one of his or her primary caregivers. The primary caregiver played a fundamental role in the intervention program through their participation in workshop activities prior to and following hands on work with their child. The purpose of including the primary caregiver as an authentic partner in the program was to encourage a definitive shift in the family, whereby caregivers would begin to implement literacy activities in their home on a daily basis. The intervention program was socially constructed through the collaboration of knowledge. The role ofthe author in the study was as the researcher, in charge of analyzing and interpreting the results of the study. There were a total of thirty-six (36) participants in the study; there were nineteen (19) participants in the intervention group and seventeen (17) participants in the control group. All of the children who participated in the study were enrolled in junior kindergarten classrooms within the Niagara Catholic District School Board. Once children were referred to the program, a Speech and Language Pathologist assessed each individual child to identify if they met the eligibility requirements for participation in the summer family literacy intervention program. To be eligible to participate, children were required to demonstrate having significant literacy needs (i.e., below 25%ile on the Test of Preschool Early Literacy described below). Children with low incident disabilities (such as Autism or Intellectual Disabilities) and children with significant English as a Second Language difficulties were excluded from the study. The research team utilized a standard pre-test-post-test comparison group design whereby all participating children were assessed with the Test of Preschool Early Literacy (Lonigan et aI., 2007), and a standard measure of letter identification and letter sound understanding. Pre-intervention assessments were conducted two weeks prior to the intervention program commencing, and the first set of the post-intervention assessments were administered immediately following the completion of the intervention program. The follow-up post-intervention assessments took place in December 2010 to measure the sustainability of the gains obtained from the intervention program. As a result of the program, all of the children in the intervention program scored statistically significantly higher on their literacy scores for Print Knowledge, Letter Identification, and Letter Sound Understanding scores than the control group at the postintervention assessment point (immediately following the completion of the program) and at the December post-intervention assessment point. For Phonological Awareness, there was no statistically significant difference between the intervention group and the control at the postintervention assessment point, however, there was a statistically significant difference found between the intervention group and the control group at the December post-intervention assessment point. In general, these results indicate that the summer family literacy intervention program made an immediate impact on the emergent literacy skills of the participating children. Moreover, these results indicate that the summer family literacy intervention program has the ability to foster the emergent literacy skills of vulnerable children, potentially reversing the negative effect the summer learning gap has on these children.