Infections in Migrants in Sweden - the Importance of Malaria and Other Parasitic Infections
试验速览
- 阶段
- 不适用
- 入组人数
- 715
- 试验地点
- 1
- 主要终点
- Parasite prevalence
研究概览
简要总结
Malaria is a parasitic disease causing substantial morbidity and mortality globally. Malaria is a potentially severe and fatal disease in non-immune individuals. In areas of intense transmission infections individuals acquired immunity that protect against clinical disease. Nonetheless, immunity is not regarding sterilizing and repeated infections often result in an asymptomatic carriage of malaria parasites. These chronic apparently asymptomatic infections have been associated with anemia, cognitive dysfunction and adverse events during pregnancy.
Global migration has increased over the last decade and has resulted in an increasing number of migrants from malaria endemic regions arriving in non-endemic countries. Migrants from malaria endemic countries may carry asymptomatic infections with malaria parasites, as well as other parasitic infections such as strongyloides and schistosomiasis, with a possible negative impact on health in this group. The prevalence of asymptomatic malaria and other parasites is not fully elucidated in migrants from different regions. Moreover, the longevity of asymptomatic carriage of malaria parasites in absence of re-exposure is not known.
The aim of this study is to assess the prevalence of malaria parasites and other parasitic infections in migrants in Sweden, both newly arrived and migrants with longer residency, and intend to evaluate the need for screening for various parasitic infections in migrants arriving in Sweden. Moreover, this study will also assess antibody responses to malaria and other parasitic diseases.
详细描述
Study participants are recruited in different ways, participation in the study is offered when attending an asylum health clinic at several sites in the Stockholm county. Secondly, patients attending the Infectious Disease outpatient clinic for non-febrile diseases (e.g. follow up of hepatitis, treatment for latent tuberculosis). Thirdly, quota refugees from Democratic Republic of the Congo or Uganda with arrival in Sweden in the years 2015-2019 with postal address in Stockholm, will be invited by letter to participate in the study .
A venous blood sample (EDTA tube) is collected from study participants at one occasion and a questionnaire including questions about patient origin and previous malaria are completed with the aid of a translator.
Blood samples are analysed in the research laboratory, where a malaria rapid diagnostic test (RDT) is performed and haemoglobin concentrations are measured (using Hemocue, point of care test) the same day as sample collection. The samples are then centrifuged, aliquoted, and stored frozen at the research laboratory. Presence of malaria parasites are analysed by realtime-PCR of the species specific 18SRNA gene in a multiplex assay. Serologic markers for other parasitic diseases (eg. schistosomiasis and strongyloides) are analysed in plasma. These analyses are performed at the reference laboratory at the Public Health Agency of Sweden.
Projected sample size is estimated using the formula n=(Z^2xP(1-P))/d^2 where P is the expected prevalence based on previous studies (5%) and d is the precision (1.5%) and Z is the confidence interval (95%). Based on these assumptions, the required sample size is n=715.
All RDT or PCR positive individuals are referred to the Department of Infectious Diseases or the Department of Pediatrics at the regional hospital for further investigations and treatment. Results from complete blood count are assessed and followed up according to clinical routine at each centre where samples were collected. Contact information to the study participant are included as part of the recruitment and consent procedures in order to be able to contact the study participants for referral.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Born in a malaria endemic country (a country with reported indigenous spread of malaria according to World Malaria Report 2019)
排除标准
- •Inability to understand study information or sign informed consent, except for children where legal guardian is asked for consent.
结局指标
主要结局
Parasite prevalence
时间窗: Measured at one occasion within 10 years from arrival in Sweden
Number of participants with ongoing malaria infection
Prevalence of other parasites focusing on strongyloides and schistosomiasis
时间窗: Measured at one occasion within 10 years from arrival in Sweden
Number of participants showing serological response to strongyloides and schistosomiasis
次要结局
- Immune responses to malaria and other parasites(A blood specimen will be collected from participants upon inclusion, and a subset of volunteers will be asked to contribute with a second blood sample after 6-12 months)