1
|
Da'Dara AA, Li C, Yu X, Zheng M, Zhou J, Shollenberger LM, Li YS, Harn DA. Prime-Boost Vaccine Regimen for SjTPI and SjC23 Schistosome Vaccines, Increases Efficacy in Water Buffalo in a Field Trial in China. Front Immunol 2019; 10:284. [PMID: 30842779 PMCID: PMC6391362 DOI: 10.3389/fimmu.2019.00284] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 02/04/2019] [Indexed: 01/14/2023] Open
Abstract
Schistosomiasis remains a serious zoonotic disease in China and the Philippines. Water buffalo and cattle account for the majority of transmission. Vaccination of water buffalo is considered a key strategy to reduce disease prevalence. Previously, we showed that vaccination of water buffalo with SjC23 or SjCTPI plasmid DNA vaccines, induced 50% efficacy to challenge infection. Here, we evaluated several parameters to determine if we can develop a two dose vaccine that maintains the efficacy of the three dose vaccine. We performed four trials evaluating: (1) lab produced vs. GLP grade vaccines, (2) varying the time between prime and boost, (3) the influence of an IL-12 adjuvant, and (4) a two dose heterologous (DNA-protein) prime-boost. We found the source of the DNA vaccines did not matter, nor did increasing the interval between prime and boost. Elimination of the IL-12 plasmid lowered homologous DNA-DNA vaccine efficacy. A major finding was that the heterologous prime boost improved vaccine efficacy, with the prime-boost regimen incorporating both antigens providing a 55% reduction in adult worms and 53% reduction in liver eggs. Vaccinated buffalo produced vaccine-specific antibody responses. These trials suggest that highly effective vaccination against schistosomes can be achieved using a two dose regimen. No adjuvants were used with the protein boost, and the potential that addition of adjuvant to the protein boost to further increase efficacy should be evaluated. These results suggest that use of these two schistosome vaccines can be part of an integrated control strategy to reduce transmission of schistosomiasis in Asia.
Collapse
Affiliation(s)
- Akram A. Da'Dara
- Department of Infectious Diseases and Global Health, Tufts Cummings School of Veterinary Medicine, Tufts University, Grafton, MA, United States
| | - Changlin Li
- Department of Infectious Diseases and Center for Tropical and Emerging Global Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Xinling Yu
- Hunan Institute of Parasitic Diseases, World Health Organisation Collaborating Centre for Research and Control of Schistosomiasis in Lake Region, Yueyang, China
| | - Mao Zheng
- Hunan Institute of Parasitic Diseases, World Health Organisation Collaborating Centre for Research and Control of Schistosomiasis in Lake Region, Yueyang, China
| | - Jie Zhou
- Hunan Institute of Parasitic Diseases, World Health Organisation Collaborating Centre for Research and Control of Schistosomiasis in Lake Region, Yueyang, China
| | - Lisa M. Shollenberger
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, United States
| | - Yue-sheng Li
- Hunan Institute of Parasitic Diseases, World Health Organisation Collaborating Centre for Research and Control of Schistosomiasis in Lake Region, Yueyang, China
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Donald A. Harn
- Department of Infectious Diseases and Center for Tropical and Emerging Global Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| |
Collapse
|
2
|
Wang X, Wang W, Wang P. Long-term effectiveness of the integrated schistosomiasis control strategy with emphasis on infectious source control in China: a 10-year evaluation from 2005 to 2014. Parasitol Res 2016; 116:521-528. [PMID: 27812902 DOI: 10.1007/s00436-016-5315-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 10/26/2016] [Indexed: 01/24/2023]
Abstract
Schistosomiasis is a neglected tropical parasitic disease of great public health significance worldwide. Currently, mass drug administration with praziquantel remains the major strategy for global schistosomiasis control programs. Since 2005, an integrated strategy with emphasis on infectious source control was implemented for the control of schistosomiasis japonica, a major public health concern in China, and pilot studies have demonstrated that such a strategy is effective to reduce the prevalence of Schistosoma japonicum infection in both humans and bovines. However, there is little knowledge on the long-term effectiveness of this integrated strategy for controlling schistosomiasis japonica. The aim of this study was to evaluate the long-term effectiveness of the integrated strategy for schistosomiasis control following the 10-year implementation, based on the data from the national schistosomiasis control program released by the Ministry of Health, People's Republic of China. In 2014, there were 5 counties in which the transmission of schistosomiasis japonica had not been interrupted, which reduced by 95.2% as compared to that in 2005 (105 counties). The number of schistosomiasis patients and acute cases reduced by 85.5 and 99.7% in 2014 (115,614 cases and 2 cases) as compared to that in 2005 (798,762 cases and 564 cases), and the number of bovines and S. japonicum-infected bovines reduced by 47.9 and 98% in 2014 (919,579 bovines and 666 infected bovines) as compared to that in 2005 (1,764,472 bovines and 33,736 infected bovines), respectively. During the 10-year implementation of the integrated strategy, however, there was a minor fluctuation in the area of Oncomelania hupensis snail habitats, and there was only a 5.6% reduction in the area of snail habitats in 2014 relative to in 2005. The results of the current study demonstrate that the 10-year implementation of the integrated strategy with emphasis on infectious source has greatly reduced schistosomiasis-related morbidity in humans and bovines. It is concluded that the new integrated strategy has remarkable long-term effectiveness on the transmission of schistosomiasis japonica in China, which facilitates the shift of the national schistosomiasis control program from transmission control to transmission interruption and elimination. However, such a strategy seems to have little effect on the shrinking of areas of snail habitats.
Collapse
Affiliation(s)
- Xiaoli Wang
- Jingzhou Hospital of Traditional Chinese Medicine, Jingzhou City, Hubei, 434000, China
| | - Wei Wang
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, Wuxi City, Jiangsu Province, 214064, China.,Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, Wuxi City, Jiangsu Province, 214064, China.,Jiangsu Institute of Parasitic Diseases, Wuxi City, Jiangsu Province, 214064, China
| | - Peng Wang
- Wuxi No. 2 Hospital Affiliated to Nanjing Medical University, No. 68 Zhongshan Road, Wuxi City, Jiangsu Province, 214002, China.
| |
Collapse
|
3
|
Liu L, Yang GJ, Zhu HR, Yang K, Ai L. Knowledge of, attitudes towards, and practice relating to schistosomiasis in two subtypes of a mountainous region of the People's Republic of China. Infect Dis Poverty 2014; 3:16. [PMID: 24955240 PMCID: PMC4064289 DOI: 10.1186/2049-9957-3-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/22/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Schistosomiasis japonica is still endemic in the People's Republic of China (P.R. China) in five provinces of lake and marshland regions and in two provinces of mountainous regions. Studies elucidated that individual and community perception, attitudes towards schistosomiasis, and hygiene behaviors were crucial factors for preventing schistosomiasis. This study sought to assess the knowledge of, attitudes towards, and practices (KAP) relating to schistosomiasis in two subtypes of a mountainous region in Eryuan County, Yunnan Province, P.R. China. The study's aim is to make suggestions for establishing more specific and effective control measures for disease transmission and interruption in two subtypes of a mountainous region with low-level infection rates. METHODS A cross-sectional study of 3,000 inhabitants was carried out in the Yongle (plateau basin) and Xinzhuang (plateau canyon) communities of Eryuan County, Yunnan Province in November and December 2011. Stratified cluster random sampling was undertaken using a uniform set of quantitative questionnaires administered by trained assistants. This was further supported with qualitative data from in-depth interviews (IDIs) conducted with ten farmers and ten students. All participants were examined for schistosomiasis using both a serological test (indirect hemagglutination assay [IHA]) and a stool examination (Kato-Katz). RESULTS The total schistosomiasis knowledge rate in Yongle (83.4%) was significantly lower than that in Xinzhuang (95.5%). In both communities, among the respondents aged 15 years or below, more than one third didn't know the name, endemic areas, and animal reservoirs of schistosomiasis. The majority of respondents in Eryuan acquired their schistosomiasis knowledge from doctors, followed by handouts and hearing from others. The infection rate was once the highest in Yongle, but is now the highest in Xinzhuang, where there are more risk factors for schistosomiasis, such as frequently grazing cattle, digging vegetables or cutting grass in the field, as well as raising cattle by free grazing. CONCLUSION In short, Eryuan County's overall knowledge rate of schistosomiasis was found to be high. Due to various dominating risk factors, different control strategies should be designed keeping in mind the two different subtypes of endemic areas for schistosomiasis in mountainous regions, namely plateau basins and plateau canyons.
Collapse
Affiliation(s)
- Lu Liu
- Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Wuxi, Jiangsu Province 214064, People's Republic of China
| | - Guo-Jing Yang
- Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Wuxi, Jiangsu Province 214064, People's Republic of China
| | - Hong-Ru Zhu
- Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Wuxi, Jiangsu Province 214064, People's Republic of China
| | - Kun Yang
- Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Wuxi, Jiangsu Province 214064, People's Republic of China
| | - Lin Ai
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, and Key Laboratory on Biology of Parasite and Vector, Ministry of Health, and WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| |
Collapse
|
4
|
New integrated strategy emphasizing infection source control to curb Schistosomiasis japonica in a marshland area of Hubei Province, China: findings from an eight-year longitudinal survey. PLoS One 2014; 9:e89779. [PMID: 24587030 PMCID: PMC3938508 DOI: 10.1371/journal.pone.0089779] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 01/27/2014] [Indexed: 11/19/2022] Open
Abstract
Background Schistosomiasis remains a major public health problem in China. The major endemic foci are the lake and marshland regions of southern China, particularly the regions along the middle and lower reach of the Yangtze River in four provinces (Hubei, Hunan, Jiangxi, and Anhui). The purpose of our study is to assess the effect of a new integrated strategy emphasizing infection source control to curb schistosomiasis in marshland regions. Methods In a longitudinal study, we implemented an integrated control strategy emphasizing infection source control in 16 villages from 2005 through 2012 in marshland regions of Hubei province. The interventions included removing cattle from snail-infested grasslands, providing farmers with mechanized farm equipment, improving sanitation by supplying tap water, building lavatories and latrines, praziquantel chemotherapy, controlling snails, and environmental modification. Results Following the integrated control strategy designed to reduce the role of bovines and humans as sources of Schistosoma japonicum infection, the prevalence of human S. japonicum infection declined from 1.7% in 2005 to 0.4% in 2012 (P<0.001). Reductions were also observed in both sexes, across all age groups, and among high risk occupations. Moreover, the prevalence of bovine S. japonicum infection decreased from 11.7% in 2005 to 0.6% in 2012 (P<0.001). In addition, all the 16 villages achieved the national criteria of infection control in 2008. Conclusion Our findings indicate that the integrated strategy was likely effective in controlling the transmission of S. japonicum in marshland regions in China.
Collapse
|
5
|
Wang S, Carlton EJ, Chen L, Liu Y, Spear RC. Evaluation of an educational intervention on villagers' knowledge, attitude and behaviour regarding transmission of Schistosoma japonicum in Sichuan province, China. Acta Trop 2013; 127:226-35. [PMID: 23711611 DOI: 10.1016/j.actatropica.2013.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 05/16/2013] [Accepted: 05/19/2013] [Indexed: 02/07/2023]
Abstract
Health education is an important component of efforts to control schistosomiasis. In China, while education programmes have been implemented intensively, few articles in recent years in either the Chinese or English literature report randomised, controlled interventions of the impacts on knowledge, attitudes and behaviours. Thus, we designed and carried out a cluster-randomised controlled education intervention trial that targeted 706 adults from rural areas in 28 villages in Sichuan, China. We evaluated the effects of the intervention on five endpoints: (1) schistosomiasis knowledge, (2) attitudes towards infection testing and treatment, (3) use of personal protective equipment (PPE), (4) reducing defecation in the field, and (5) reducing dermal contact with potentially contaminated water sources. The results indicated that people in both the intervention and control groups showed improvement in knowledge, attitudes and reduction in field-defecation in the follow-up surveys. However, there was little evidence that suggested statistically significant differences between the two groups regarding any endpoint. Participation in intervention classes was associated with age, gender, occupation and education level. Our study suggests short-term health education interventions may not be effective in improving schistosomiasis knowledge or in the adoption of health-protective behaviours. This might be partially due to the spontaneous learning process of people subject to repeated surveys and other disease control activities. Considering the difficulties of occupation-associated behaviour change and knowledge reinforcement in general, longer-term education programmes should be considered in the future.
Collapse
|
6
|
Balen J, Liu ZC, McManus DP, Raso G, Utzinger J, Xiao SY, Yu DB, Zhao ZY, Li YS. Health access livelihood framework reveals potential barriers in the control of schistosomiasis in the Dongting Lake area of Hunan Province, China. PLoS Negl Trop Dis 2013; 7:e2350. [PMID: 23936580 PMCID: PMC3731233 DOI: 10.1371/journal.pntd.0002350] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 06/19/2013] [Indexed: 01/02/2023] Open
Abstract
Background Access to health care is a major requirement in improving health and fostering socioeconomic development. In the People's Republic of China (P.R. China), considerable changes have occurred in the social, economic, and health systems with a shift from a centrally planned to a socialist market economy. This brought about great benefits and new challenges, particularly for vertical disease control programs, including schistosomiasis. We explored systemic barriers in access to equitable and effective control of schistosomiasis. Methodology Between August 2002 and February 2003, 66 interviews with staff from anti-schistosomiasis control stations and six focus group discussions with health personnel were conducted in the Dongting Lake area, Hunan Province. Additionally, 79 patients with advanced schistosomiasis japonica were interviewed. The health access livelihood framework was utilized to examine availability, accessibility, affordability, adequacy, and acceptability of schistosomiasis-related health care. Principal Findings We found sufficient availability of infrastructure and human resources at most control stations. Many patients with advanced schistosomiasis resided in non-endemic or moderately endemic areas, however, with poor accessibility to disease-specific knowledge and specialized health services. Moreover, none of the patients interviewed had any form of health insurance, resulting in high out-of-pocket expenditure or unaffordable care. Reports on the adequacy and acceptability of care were mixed. Conclusions/Significance There is a need to strengthen health awareness and schistosomiasis surveillance in post-transmission control settings, as well as to reduce diagnostic and treatment costs. Further studies are needed to gain a multi-layered, in-depth understanding of remaining barriers, so that the ultimate goal of schistosomiasis elimination in P.R. China can be reached. China has made great strides toward reducing the burden of schistosomiasis, facilitated by sustained political commitment and a multi-faceted, integrated control strategy. The ultimate goal is disease elimination, which might be challenging due to high rates of re-infection, clusters of re-emergence, and growing health disparities. Market-oriented reforms and system-wide policies within the health care system offer new opportunities, but also entail challenges for the national schistosomiasis control program. Few studies have examined systemic barriers to equitable and effective schistosomiasis control in China. We explored the five core dimensions of access to health care, placing emphasis on schistosomiasis in the Dongting Lake area of Hunan Province. We collected and analyzed perspectives from staff working at local anti-schistosomiasis control stations and designated schistosomiasis hospitals, and from patients with advanced schistosomiasis. Our data suggest that a lack of affordability and high out-of-pocket expenditure posed a major barrier to the health care users, as did a lack of relevant health-information, and poorly accessible diagnostic and specialized surgical services. The lessons learned from this work are important in the design and development of disease control programs and entail key policy implications for schistosomiasis elimination.
Collapse
Affiliation(s)
- Julie Balen
- Molecular Parasitology Laboratory, Division of Infectious Diseases, Queensland Institute of Medical Research, Brisbane, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
7
|
The new national integrated strategy emphasizing infection sources control for schistosomiasis control in China has made remarkable achievements. Parasitol Res 2013; 112:1483-91. [DOI: 10.1007/s00436-013-3295-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Accepted: 01/11/2013] [Indexed: 10/27/2022]
|