The risk of congenital neurologic defects related to Zika virus (ZIKV) infection has ranged from 6 to 42% in various reports. The aim of this study was to estimate this risk among pregnant women with symptomatic ZIKV infection in French territories in the Americas.

In French Guiana, a French overseas territory in South America, 6 to 10 thousands undocumented persons work illegally in gold mining sites in the Amazonian forest. Precarious life conditions lead to poor health but few data exist on the health status of illegal gold miners in French Guiana. The objective of this article was to describe the sociodemographic and health status of this vulnerable population. A prospective cross-sectional survey was conducted in 2015 on gold mine supply sites at the border between French Guiana and Suriname. Health status was assessed through medical examination, past medical history, haemoglobin concentration, and HIV and malaria testing. A questionnaire was used to collect data about the migration itinerary and life conditions on mining sites. Among the 421 adults included in the study, 93.8% (395/421) were Brazilian, mainly from Maranhão (55.7%, 220/395), the poorest Brazilian state. The sex ratio was 2.4. Overall, 48% of persons never went to school or beyond the primary level. The median time spent in gold mining was quite long (10 years), with a high turn-over. One third of the surveyed population (37.1%, 156/421) had high blood pressure, and only two had a medical follow-up. Most persons had experienced malaria (89.3%, 376/421). They declared frequent arboviroses and digestive disorders. Active leishmaniasis was observed in 8.3% of gold miners. Among women, 28.5% were anemic. Concerning HIV, 36.6% (154/421) of persons, mainly men, never got tested before and 6 were tested positive, which represented an HIV prevalence of 1.43% (95%CI =0.29–2.5). These findings support the hypothesis that mining in remote areas is linked to several specific illnesses. Theoretically, gold miners would be presumed to start their economical migration to French Guiana as a healthy group. However, their strenuous working and living conditions there lead to poor health caused by infectious and non infectious diseases. This description of their health status is precious for health policy planners in French Guiana given the importance of controlling communicable disease, and the severity and range of specific illnesses acquired by this neglected population. Clinical trial registration PRS N° NCT02903706 . Retrospectively registered 09/13/2016.

Malaria is endemic in French Guiana, an overseas territory of France on the Guiana Shield. Since 2005, notified malaria cases are decreasing. However, new data show that malaria affects many Brazilian gold miners working illegally in French Guiana, the majority of whom are not counted in official data. In addition, one major concern is the usual practice of improper self-treatment in this mining population, raising fear of the development of anti-malarial resistance. This prospective study, conducted in 2015, aimed to estimate the prevalence of Plasmodium spp. in illegal gold miners working in French Guiana. The recruitment of gold miners was carried out in resting sites along the French Guiana-Suriname border, where they go for supplies, medical care or leisure. After recording agreement, three malaria diagnostic methods were performed: rapid diagnostic test, microscopy and PCR. Among 421 persons recruited in the study, malaria prevalence, detected by nested-PCR, was 22.3 % (CI [18.3–26.3], n = 94/421) of which 84 % were asymptomatic. This significant malaria reservoir in a mobile and illegal population with difficult access to a health care system raises the threat of artemisinin resistance and puts the population of the Guiana Shield at risk of new transmission foci while countries of the region aim at malaria elimination. Even though French legislation may hamper dealing with this population, France must face the reality of malaria in illegal gold miners in order to meet its commitment to malaria elimination.

Purpose of Review: Following Paraguay and Argentina, several countries from the Amazon region aim to eliminate malaria. To achieve this, all key affected and vulnerable populations by malaria, including people working on gold mining sites, must be considered. What is the situation of malaria in these particular settings and what are the challenges? This literature review aims to compile knowledge to answer these questions. Recent Findings: The contexts in which gold miners operate are very heterogeneous: size and localization of mines, links with crime, administrative status of the mines and of the miners, mobility of the workers or national regulations. The number of malaria cases has been correlated with deforestation (Brazil, Colombia), gold production (Colombia), gold prices (Guyana), or location of the mining region (Peru, Colombia, Venezuela, Guyana). The burden of malaria in gold mines differs between territories: significant in Guyana, French Guiana, or Venezuela; lower in Brazil. Although Plasmodiumvivax causes 75% of malaria cases in the Americas, P. falciparum is predominant in several gold mining regions, especially in the Guiana Shield. Because of the remoteness from health facilities, self-medication with under-the-counter antimalarials is frequent. This constitutes a significant risk for the emergence of new P. falciparum parasites resistant to antimalarial drugs. Summary: Because of the workers’ mobility, addressing malaria transmission in gold mines is essential, not only for miners, but also to prevent the (re-)emergence of malaria. Strategies among these populations should be tailored to the context because of the heterogeneity of situations in different territories. The transnational environment favoring malaria transmission also requires transborder and regional cooperation, where innovative solutions should be considered and evaluated.

Illegal gold miners in French Guiana, a French overseas territory (‘département’) located in Amazonia, often carry malaria parasites (up to 46.8%). While the Guiana Shield Region aims at malaria elimination, the high prevalence of Plasmodium in this hard-to-reach population in conjunction with frequent incorrect use of artemisinin-based anti-malarials could favour the emergence of resistant parasites. Due to geographical and regulatory issues in French Guiana, usual malaria control strategies cannot be implemented in this particular context. Therefore, new strategies targeting this specific population in the forest are required. Numerous discussions among health institutions and scientific partners from French Guiana, Brazil and Suriname have led to an innovative project based on the distribution of kits for self-diagnosis and self-treatment of Plasmodium infections. The kit-distribution will be implemented at “resting sites”, which are areas across the border of French Guiana regularly frequented by gold miners. The main objective is to increase the appropriate use and complete malaria treatment after a positive malaria diagnosis with a rapid test, which will be evaluated with before-and-after cross-sectional studies. Monitoring indicators will be collected from health mediators at the time of kit distribution and during subsequent visits, and from illegal gold miners themselves, through a smartphone application. The project funding is multisource, including Ministries of Health of the three countries, WHO/PAHO, and the European Union. This project will start in April 2018 as a 18 month pilot study led by the Clinical Investigation Centre of Cayenne. Results should be available at the end of 2019. This innovative approach may have several limitations which should be taken into account, as potential side effects, kit misuse or resale, declarative main criteria, or no Plasmodium vivax curative treatment. Close monitoring is thus needed. This project may be the best available solution to a specific and important public health challenge in the Guiana Shield. If the use of self-diagnosis and self-treatment approach is effective, this strategy could be sustained by health institutions in the region.