A prescription for sustaining community engagement in malaria elimination on Aneityum Island, Vanuatu: an application of Health Empowerment Theory

Abstract Background Community engagement has contributed to disease control and elimination in many countries. Community engagement in malaria elimination (ME) on Aneityum Island has been sustained since its introduction in the early 1990s. Capacity developed within this population has led to a health empowered community response. Health Empowerment Theory (HET) can account for the innovative community actions and capacity development efforts taken to realize and sustain meaningful changes in well-being. This study used the HET framework to investigate participant perceptions of ME efforts on the island focusing on two HET elements, personal and social-contextual resources. The purpose of this study was to explore the role of empowerment as a critical element of community engagement. Methods Six focus group discussions, ten key informant interviews and 17 in-depth interviews were conducted in July 2012 on Aneityum. Both deductive and inductive approaches to qualitative content analysis were used to identify themes, which were condensed, coded and classified based on the HET elements above. Results Awareness and use of personal and social-contextual resources played an important role in ME efforts. Most participants shared their knowledge to prevent malaria reintroduction. Many participants reported their skills needed for behavioral maintenance, problem-solving or leadership. Participants who perceived a threat took preventive actions even in the dry season. Community leaders focused on second generation capacity development. A local health coalition provided ME services. Members of networks were sources of information and assistance. Face-to-face was the preferred method of communication. Barriers to engagement (e.g., financial difficulties, health literacy issues and underdeveloped infrastructure) were minimized through active collaboration and mutual assistance. Conclusions In the community engagement continuum, health empowerment develops incrementally overtime as people gain their knowledge and skills, form coalitions and develop collaborative networks (social capital) to make decisions and take action for change. Community engagement, which facilitates local personal and social-contextual resource development, has potential for ME and multilevel empowerment through community-based capacity development processes. These self-empowered communities have written and will continue to write a ‘prescription’ for sustaining high levels of engagement.http://deepblue.lib.umich.edu/bitstream/2027.42/112066/1/12936_2015_Article_779.pd

Active target MAIKo to investigate cluster structures in unstable nuclei

Study on clustering of nucleons in nuclei is recently focusing on unstable nuclei where new kinds of structures, namely molecular structures with excess nucleons, are predicted. The Coulomb shift of energy in the mirror system is suggested to reflect the size of these structures. Although the missing mass spectroscopy is expected to give access to these structures even beyond particle decay thresholds without any biases in excitation energy spectra but the detection of very low energy particles is challenging. To satisfy the requirement, a new active target system MAIKo has been developed at RCNP. The detector was commissioned using a 13C beam under the same kinematical condition as that of RI beam experiments

Determinants of the use of insecticide-treated bed nets on islands of pre- and post-malaria elimination: an application of the health belief model in Vanuatu

Abstract Background Insecticide-treated nets (ITNs) are an integral piece of any malaria elimination strategy, but compliance remains a challenge and determinants of use vary by location and context. The Health Belief Model (HBM) is a tool to explore perceptions and beliefs about malaria and ITN use. Insights from the model can be used to increase coverage to control malaria transmission in island contexts. Methods A mixed methods study consisting of a questionnaire and interviews was carried out in July 2012 on two islands of Vanuatu: Ambae Island where malaria transmission continues to occur at low levels, and Aneityum Island, where an elimination programme initiated in 1991 has halted transmission for several years. Results For most HBM constructs, no significant difference was found in the findings between the two islands: the fear of malaria (99%), severity of malaria (55%), malaria-prevention benefits of ITN use (79%) and willingness to use ITNs (93%). ITN use the previous night on Aneityum (73%) was higher than that on Ambae (68%) though not statistically significant. Results from interviews and group discussions showed that participants on Ambae tended to believe that risk was low due to the perceived absence of malaria, while participants on Aneityum believed that they were still at risk despite the long absence of malaria. On both islands, seasonal variation in perceived risk, thermal discomfort, costs of replacing nets, a lack of money, a lack of nets, nets in poor condition and the inconvenience of hanging had negative influences, while free mass distribution with awareness campaigns and the malaria-prevention benefits had positive influences on ITN use. Conclusions The results on Ambae highlight the challenges of motivating communities to engage in elimination efforts when transmission continues to occur, while the results from Aneityum suggest the possibility of continued compliance to malaria elimination efforts given the threat of resurgence. Where a high degree of community engagement is possible, malaria elimination programmes may prove successful.http://deepblue.lib.umich.edu/bitstream/2027.42/111292/1/12936_2014_Article_3647.pd

ヴァヌアツのマラリア流行島嶼におけるIL4多型とIgE濃度

血中IgE上昇に帰結するIL4プロモーターの遺伝的変異が,マラリアに対する感受性と相関することが最近の研究によって示唆されてきている.本研究においては集団遺伝学的方法を用いヴァヌアツにおけるマラリア流行度が異なる3島嶼において,IL4-590および+33塩基における変異対立遺伝子頻度,血中総IgEおよび熱帯熱マラリア原虫特異的IgE濃度を調べた.3島嶼は中等度の流行が続くMalakula,中等度の流行だが対策が功を奏しているAneityumおよびマラリア流行がないFutunaである.これらの島嶼住民より採取した血液サンプルよりIL4-590および+33についてそれぞれ計878および750サンプルの解析を行った.変異対立遺伝子頻度はこれら3島嶼間においてC-590Tが0.27～0.39,C+33Tが0.39～0.48の範囲で変動した.両対立遺伝子間には顕著な連鎖不均衡が認められた(p<0.001).これら両変異対立遺伝子ともAneityumにおいてはFutunaより高い頻度で認められた(p<0.05).AneityumにおいてはIL4+33位における変異対立遺伝子の存在する群での血中熱帯熱マラリア原虫特異的IgE濃度は有意に上昇していた(p<0.05).しかしながら,これらの関係はMalakulaにおいては認められなかった.本研究はメラネシア住民集団において当該変異遺伝子頻度に関する最初の報告である.見出された変異対立遺伝子頻度はこれまで報告されている,より高いアジア住民集団とより低いヨーロッパ住民集団の中間の値であった.さらにIL4多型が特異的IgEとマラリア病形の関係に関る遺伝的因子の一つであることが示唆された.Recent findings suggest that susceptibility to malaria is associated with genetic variants in the IL4 promoter region, resulting in the up-regulation of serum IgE. In this study, using a population-based approach, we investigated the mutant allele frequencies at positions -590 and +33 of the IL4 gene and total and Plasmodium (P.) falciparum-specific IgE levels on 3 islands with variable malaria endemicities in Vanuatu: Malakula (meso-endemic), Aneityum (meso-endemic with intervention), and Futuna (non-endemic). A total of 878 and 750 samples were typed for -590 and +33 positions, respectively. Variant allele frequencies varied from 0.27 to 0.39 for C-590T and from 0.39 to 0.48 for C+33T among 3 islands. There was a strong linkage disequilibrium between the 2 alleles (p<0.001). For both mutant alleles higher frequencies were detected in Aneityum than in Futuna (p<0.05). In Aneityum there was a significant association between the carriage of C+33T allele and increased levels of P. falciparum-specific IgE (p<0.05). However these relations were not observed in Malakula. This is the first report on IL4 polymorphisms in Melanesian populations. The observed mutant allele frequencies lay between higher values in Asian populations and rather lower values in Caucasians. The data suggest that IL4 promoter polymorphisms may be one of the genetic factors that explain relations between malaria disease and IgE

ヴァヌアツのマラリア流行島嶼におけるIL4多型とIgE濃度

血中IgE上昇に帰結するIL4プロモーターの遺伝的変異が,マラリアに対する感受性と相関することが最近の研究によって示唆されてきている.本研究においては集団遺伝学的方法を用いヴァヌアツにおけるマラリア流行度が異なる3島嶼において,IL4-590および+33塩基における変異対立遺伝子頻度,血中総IgEおよび熱帯熱マラリア原虫特異的IgE濃度を調べた.3島嶼は中等度の流行が続くMalakula,中等度の流行だが対策が功を奏しているAneityumおよびマラリア流行がないFutunaである.これらの島嶼住民より採取した血液サンプルよりIL4-590および+33についてそれぞれ計878および750サンプルの解析を行った.変異対立遺伝子頻度はこれら3島嶼間においてC-590Tが0.27～0.39,C+33Tが0.39～0.48の範囲で変動した.両対立遺伝子間には顕著な連鎖不均衡が認められた(p<0.001).これら両変異対立遺伝子ともAneityumにおいてはFutunaより高い頻度で認められた(p<0.05).AneityumにおいてはIL4+33位における変異対立遺伝子の存在する群での血中熱帯熱マラリア原虫特異的IgE濃度は有意に上昇していた(p<0.05).しかしながら,これらの関係はMalakulaにおいては認められなかった.本研究はメラネシア住民集団において当該変異遺伝子頻度に関する最初の報告である.見出された変異対立遺伝子頻度はこれまで報告されている,より高いアジア住民集団とより低いヨーロッパ住民集団の中間の値であった.さらにIL4多型が特異的IgEとマラリア病形の関係に関る遺伝的因子の一つであることが示唆された.Recent findings suggest that susceptibility to malaria is associated with genetic variants in the IL4 promoter region, resulting in the up-regulation of serum IgE. In this study, using a population-based approach, we investigated the mutant allele frequencies at positions -590 and +33 of the IL4 gene and total and Plasmodium (P.) falciparum-specific IgE levels on 3 islands with variable malaria endemicities in Vanuatu: Malakula (meso-endemic), Aneityum (meso-endemic with intervention), and Futuna (non-endemic). A total of 878 and 750 samples were typed for -590 and +33 positions, respectively. Variant allele frequencies varied from 0.27 to 0.39 for C-590T and from 0.39 to 0.48 for C+33T among 3 islands. There was a strong linkage disequilibrium between the 2 alleles (p<0.001). For both mutant alleles higher frequencies were detected in Aneityum than in Futuna (p<0.05). In Aneityum there was a significant association between the carriage of C+33T allele and increased levels of P. falciparum-specific IgE (p<0.05). However these relations were not observed in Malakula. This is the first report on IL4 polymorphisms in Melanesian populations. The observed mutant allele frequencies lay between higher values in Asian populations and rather lower values in Caucasians. The data suggest that IL4 promoter polymorphisms may be one of the genetic factors that explain relations between malaria disease and IgE

CTLA-4 polymorphisms and anti-malarial antibodies in a hyper-endemic population of Papua New Guinea

In malaria endemic areas, people naturally acquire an age-related immunity to malaria. Part of this immunity involves anti-malarial specific antibodies. Acquisition of these malaria-specific antibodies depends not only on exposure to malaria parasites but also on the human genetic predisposition. CTLA-4 is a costimulatory molecule that delivers an inhibitory signal to suppress T-cell as well as B-cell responses. We investigated associations between malaria-specific antibody levels and CTLA-4 polymorphisms in 189 subjects living in a hyper-endemic area of Papua New Guinea (PNG), where both P. falciparum and P. vivax are prevalent. We determined P. falciparum/ P. vivax specific IgG/IgE levels (Pf-IgG, Pv-IgG, Pf-IgE, Pv-IgE) and polymorphisms in the CTLA-4 gene at position -1661 promoter region (A/G), the +49 exon 1 non-synonymous mutation (A/G), and the +6230 3‘-UTR (A/G). All quantified antibody levels were significantly higher in subjects > 5 years (n = 150) than in subjects 5 years of age (n = 39). In children 5 years old, significant associations were detected between CTLA-4 +49 (GG/AG vs. AA) and Pv-IgG (median 18.7 vs. 13.7 Μg/ml, P = 0.017) and Pv-IgE (266.6 vs. 146.5 pg/ml, P = 0.046). No significant difference was observed in subjects > 5 years old. These results suggest that the CTLA-4+49 polymorphism influenced Pv-IgG and Pv-IgE levels among children less than five years old in the studied population, which may regulate the age- and species-specific clinical outcomes of malaria infection