Prevalence and Incidence of Lassa Virus Infection in Southern Mali
Ключавыя словы
Рэферат
Апісанне
In West Africa, as many as 300,000 people are infected annually with Lassa virus (LASV), resulting in approximately 5,000 deaths. Most commonly, human infection comes from contact with infected rodent hosts (Mastomys natalensis), or ingestion or inhalation of virus-laden particles. Person-to-person transmission is also well documented and can cause outbreaks, especially in nosocomial settings. Infection in pregnancy, especially the third trimester, is particularly severe, with maternal mortality rates estimated at 20% and fetal mortality rates nearing 100%. A survey of rodents captured in the village of Soromba (rural commune of Sibirila, district of Bougouni, Mali) found that 25% of M. natalensis had evidence of LASV infection. A 2015 study of LASV infection in the human populations of this region showed seroprevalence of 33.2% and annual incidence rate of 6.3% in 2016.
The purpose of this serosurvey study is to determine the prevalence and incidence of human exposure to LASV in the administrative districts of Bougouni, Yanfolila, and Kolondieba in southern Mali. The study involves 2 separate sub-studies. Study 1 is a cross-sectional serosurvey of residents of the general population selected from a census. The study will follow up to 500 participants at each of 4 study sites. Participants will be asked to give blood samples at baseline and annually for 3 years. Study 2 is a clinic-based serosurvey conducted at local health centers following up to 500 participants per year at each of the 4 study sites. Patients who report with febrile illness suggestive of Lassa fever will be asked to give blood and nasal swab samples, then return for follow-up visits 5 and 21 days later for clinical consultation and additional blood and swab collection.
All participants will be provided with free medical treatment according to local standard of care as needed for the duration of the study. They will be followed passively between study visits and instructed to report to their local health center if they have a fever. Individual participation for both studies will last through a common end date, up to 4 years.
Blood and nasal swab samples will be used to identify history of or current LASV infection and for exploratory studies into the biochemistry and pathophysiology of LASV infection. Elucidating the prevalence of LASV infection in the populations of southern Mali may help Malian authorities improve surveillance, and additional research may help develop diagnostics and treatment.
Даты
| Апошняя праверка: | 03/15/2020 |
| Упершыню прадстаўлена: | 12/18/2018 |
| Меркаваная колькасць заявак прадстаўлена: | 12/18/2018 |
| Першае паведамленне: | 12/19/2018 |
| Апошняе абнаўленне адпраўлена: | 07/27/2020 |
| Апошняе абнаўленне апублікавана: | 07/28/2020 |
| Фактычная дата пачатку даследавання: | 08/02/2020 |
| Разліковая дата першаснага завяршэння: | 12/30/2024 |
| Разліковая дата завяршэння даследавання: | 12/30/2024 |
Стан альбо хвароба
Фаза
Групы ўзбраенняў
| Рука | Ўмяшанне / лячэнне |
|---|---|
| Clinical Cohort This study population will consist of patient volunteers that visit one of our clinical sites withan undiagnosed febrile illness. | |
| Cross-sectional Cohort Cross sectional study participants are volunteers from the general population selected from census lists. |
Крытэрыі прыдатнасці
| Узрост, які мае права на вучобу | 1 Year Каб 1 Year |
| Пол, прыдатны для навучання | All |
| Метад адбору проб | Probability Sample |
| Прымае здаровых валанцёраў | Так |
| Крытэрыі | - INCLUSION CRITERIA: 1. Age greater than or equal to 6 months to 99 years. 2. Resident of one of the study administrative districts, or moved to the area at least 3 months ago. 3. Able to provide informed consent. 4. Agrees to allow storage of samples for future research. Additional inclusion criteria for the cross-sectional study (study 1): 1. No plans to relocate before the study end date. Additional inclusion criteria for the clinic-based study (study 2): 1. Has fever (temperature greater than or equal to 38 C), or has had antecedent of fever for at least 2 consecutive days at the time of screening. 2. One or more of the following: 1. Excluded typhoid fever and malaria (negative or 1+ in thick smear) and has at least 1 of the following symptoms: chest pain, sore throat, headache, muscle pain,vomiting, and diarrhea. 2. Shows bleeding or facial edema. 3. Does not respond to anti-malarials or antibiotics after 2 days of treatment. 4. Had contact with a confirmed LF case within the last 3 weeks. EXCLUSION CRITERIA: General exclusion criteria: 1. Any condition that, in the opinion of the investigator, contraindicates participation in this study, including conditions that could hinder compliance or that could place participants or study staff at increased risk. 2. Pregnancy. Additional exclusion criteria for the clinic-based study (study 2): 1. Signs or symptoms of fever-associated conditions other than LF, such as bronchopneumonia, urinary tract infection, or any other infection that may cause fever. Co-enrollment guidelines: Participants may be co-enrolled in other studies; however, study staff should be notified of co-enrollment |
Вынік
Першасныя вынікі
1. Determine the prevalence and annual incidence of seoconversion to LASV infection in the general population around each study site in the LASV endemic area of southern Mali. [At time of study start]
2. Determine the incidence of LF in febrile patients attending health centers in southern Mali [Over 3 years]
Меры другаснага выніку
1. Determine the biological, clinical, and virologic parameters of LASV-Soromba infection in study participants with LF. [At time of study start.]
