Vincent Pommier de Santi

Three-Toed Sloth as Putative Reservoir of Coxiella burnetii, Cayenne, French Guiana

To the Editor: Q fever is an emerging zoonosis and a major public health concern in French Guiana, a French overseas region located on the northeastern coast of South America (1,2). Most cases occur in the city of Cayenne (3), specifically in the suburbs, where houses are near wooded hills (4). Genotyping performed by using multispacer sequence typing showed that MST17, a unique genotype of C. burnetii, circulates in Cayenne and is responsible for epidemics of Q fever (5). C. burnetii transmission peaks during the rainy season, and the incidence of Q fever usually increases 1–3 months later (6). The animal reservoir of C. burnetii in French Guiana is unknown; previous studies have excluded domestic ruminants, which are known to be C. burnetii reservoirs elsewhere in the world (6). Four serologic surveys showed few C. burnetii–positive opossums, dogs, rodents (Proechimys spp.), bovines, or birds in French Guiana (7). In 2013, using real-time PCR (qPCR) analysis of vaginal swab samples, we showed that 6/158 (3.8%) dogs from Cayenne and 0/206 bats from the coastal area of French Guiana were positive for C. burnetii (cycle threshold [Ct]<35). One of the positive samples was identified as genotype MST17 (5). A case–control study among humans identified several risk factors for Q fever, including living near a forest and the presence of wild animals near the house (6). During January–April 2013, a Q fever outbreak occurred in Tiger Camp, a military residential area located at the top of a wooded hill in Cayenne. Vaginal swab samples were collected from animals living in the area (13 goats, 8 sheep, 7 bats, 34 birds, 2 opossums, 4 iguanas, and 17 geckos); all samples were negative for C. burnetii by qPCR. In addition, serologic tests for C. burnetii were negative for samples from all 37 small ruminants maintained near the outbreak area. In January 2014, a dead (accidental death) female 3-toed sloth (Bradypus tridactylus) (Figure, panel A) was found on the road near the residence of a Q fever patient. We retrieved the sloth and collected feces, spleen, liver, kidney, lung, and uterus samples and a vaginal swab sample. A total of 16 ticks were removed from the sloth and stored in 70% alcohol. Figure Putative reservoir of Coxiella burnetii in Cayenne, French Guiana A) A 3-toed sloth (Bradypus tridactylus) in its natural habitat in Tiger Camp, a military residential area located at the top of a wooded hill in Cayenne, French Guiana (photograph by S. ... DNA was extracted from the feces, organs, and ticks by using the BioRobot EZ1 Workstation (QIAGEN, Courtaboeuf, France). qPCR targeting the repeated insertion sequence IS1111 was performed by using a CFX96 Touch Real-Time PCR Detection System (Bio-Rad, Marne la Coquette, France) as described (8). We confirmed all positive results by performing a second qPCR targeting the IS30a repeated sequence. DNA samples with Ct values <35 in both assays were considered positive for C. burnetii. A standard calibration curve quantifying the target IS1111 was generated by using 10-fold serial dilutions of C. burnetii Nine Mile strain. The number of IS1111 intergenic sequences found in the genome of strain C. burnetii MST17 was identical to that for the Nine Mile strain (F. D’Amato, unpub. data); thus, the qPCR that we used was valid for quantifying the number of C. burnetii MST17 IS1111 copies/mL in samples we collected (5). qPCR analysis showed that the feces were highly positive for C. burnetii; the sample had a low Ct value of 23, corresponding to 7 log10 DNA copies/mL (9). The spleen was also positive for C. burnetii; the Ct value was 34, corresponding to 3.6 log10 DNA copies/mL. Results for the other samples were negative. Using morphologic criteria, we identified all 16 ticks collected from the sloth as Amblyomma geayi (Figure, panel B). We performed C. burnetii–specific qPCR on the ticks; 14 (88%) were positive. We genotyped C. burnetii–positive DNA from the feces and from 6 of the 16 ticks by using multispacer sequence typing as described (5). All samples were identified as MST17, the unique genotype circulating in Cayenne (5). After obtaining the laboratory results, we confirmed that a local group in charge of the collection and treatment of injured animals usually released rehabilitated 3-toed sloths into Tiger Camp. Residents of Tiger Camp regularly observed and came into contact with the sloths, and ticks were frequently observed on the fur of the animals. Furthermore, 3 Q fever patients from Cayenne reported contact with sloths. Feces from the sloth in this study were highly infectious for C. burnetii. Because sloths live in tall trees and can shed this bacterium in their feces, human contamination might occur through inhalation of infectious aerosols from feces. The high prevalence of C. burnetii infection in ticks also suggests possible transmission through tick bites or from aerosols of tick feces that have been deposited on the skin of animal hosts; such feces can be extremely rich in bacteria and highly infectious (10). In this 2013 outbreak of Q fever, epidemiologic studies led to the identification of 3-toed sloths as a putative source of C. burnetii infection. Further investigations are needed to confirm the role of sloths as a reservoir for C. burnetii in French Guiana and to implement efficient measures to prevent transmission to humans.

Malaria Hyperendemicity and Risk for Artemisinin Resistance among Illegal Gold Miners, French Guiana.

To assess the prevalence of malaria among illegal gold miners in the French Guiana rainforest, we screened 205 miners during May–June 2014. Malaria prevalence was 48.3%; 48.5% of cases were asymptomatic. Patients reported self-medication with artemisinin-based combination therapy. Risk for emergence and spread of artemisinin resistance among gold miners in the rainforest is high.

Malaria in French Guiana Linked to Illegal Gold Mining.

To the Editor: French Guiana, an overseas territory of France and part of the European Union, is located on the northeast coast of South America (Figure). During 2008– 2014, the number of malaria cases reported in French Guiana drastically decreased (1). The littoral area (≈30 km–wide Atlantic Ocean coastal band between the cities of Awala-Yalimapo and Ouanary) and the lower part of the Maroni River bordering Suriname (between the cities of Maripasoula and Saint-Laurent du Maroni) are considered malaria free, but this status may not reflect malaria transmission in the inland rainforest (2–4). Since 2008, French Armed Forces have been involved in military operations to control and reduce illegal gold mining activities in forested areas. Soldiers and military policemen usually spend 1–3 weeks in illegal gold mining sites in remote rainforest areas before returning to the littoral area or to bases on rivers bordering Suriname and Brazil. Despite malaria prevention strategies (5), these deployments have resulted in several outbreaks and increased malaria incidence among French forces (6). Most malaria episodes occurred during or just after deployments, so presumed locations of exposure can be easily identified. Figure Geographic distribution of presumed places of exposure for 742 single-infection Plasmodium vivax (586) and P. falciparum (156) malaria cases reported among French Armed Forces in French Guiana, 2008–2014. Numbers on map show illegal gold mining ... Information about malaria cases was collected during 2008–2014 by the French Armed Forces’ epidemiologic surveillance system by using a mandatory, specific form that captured putative place of malaria exposure and biologic data for case-patients (6). Geographic coordinates of presumed places of contamination were uploaded into a geographic information system (ArcGIS; http://www.esri.com/software/arcgis/) to produce a malaria distribution map. During 2008–2014, a total of 1,070 malaria cases were reported to the French Armed Forces’ epidemiologic surveillance system. Plasmodium vivax accounted for 78.8% (843/1,070), P. falciparum for 18.0% (193/1,070), and mixed infection (P. vivax and P. falciparum) for 3.2% (34/1,070). Places where malaria exposure occurred were identified for 742 cases of single malaria (586 P. vivax and 156 P. falciparum) infections (Figure). Cases occurring along the Maroni and Oyapock Rivers delimiting the frontiers with Suriname and Brazil, respectively, accounted for 25.3% (188/742). The other cases (74.7%, 554/742) were associated with exposures during military operations in illegal gold mining sites. Entomologic investigations were conducted in 2 malaria epidemic locations where French forces were deployed: Eau-Claire and Dagobert. Collected Anopheles spp. mosquito specimens were identified by using morphologic keys specific to the Guyana Shield, a geomorphologic formation underlying French Guiana and other areas (7). Nonidentifiable Anopheles mosquito specimens were further identified molecularly (8). PCR products from the internal transcribed spacer 2 gene were sequenced, and Anopheles species were identified by comparing sequences to those in GenBank (http://www.ncbi.nlm.nih.gov/genbank/) by searching with BLAST (http://blast.ncbi.nlm.nih.gov/Blast.cgi). Testing for P. falciparum and P. vivax infections was conducted for all Anopheles spp. specimens by using nested PCR, as described (9). In May 2013, a malaria outbreak occurred 1 month after military deployment of 100 soldiers at Eau Claire (3.56075°N, −53.21268°E; Figure), where 1 Mosquito Magnet trap (Woodstream Corporation, Lititz, PA, USA) baited with octenol was used to sample Anopheles mosquitoes during April 22–May 12, 2013 (10). The attack rate among the soldiers was 5.0% (5/100): 4 P. vivax and 1 P. falciparum malaria cases. Fifty-three Anopheles mosquito specimens were caught during the 20 days before the outbreak and identified as comprising 4 species (Technical Appendix Table). P. falciparum infection was detected in 2 Anopheles species: 1 (12.5%) of 8 An. ininii and 1 (5.0%) of 19 An. nuneztovari s.l. mosquitoes collected; P. vivax infection was found in 1 (5.5%) of 19 An. nuneztovari s.l. mosquitoes. In September 2013, another malaria outbreak occurred 3 weeks after the deployment of 15 soldiers in Dagobert (4.06028°N, −53.70667°E; Figure). The attack rate among these soldiers was 53.3% (8/15): 7 P. vivax infections and 1 co-infection with P. vivax and P. falciparum. Mosquitoes were collected 3 months later by using human landing catches during 5 consecutive days. The area had been free of illegal gold mining activities since the 15 soldiers were deployed. A total of 321 Anopheles mosquitoes were collected in this location; 95.6% were identified as the same 4 species as in the Eau Claire mosquito collection (Technical Appendix Table). Only 1 specimen (0.4%, 1/282), An. darlingi mosquito, was infected with P. vivax. These results suggest a high level of malaria transmission involving An. darlingi and other Anopheles species as primary vectors of malaria in the rainforest. The findings probably highlight malaria hyperendemicity in communities of undocumented gold miners, who are often mobile and pose a challenge for controlling malaria and other infectious diseases in the region. Indeed, these gold miners could reintroduce malaria in areas where competent vectors exist in the coastal part of French Guiana and in Surinam and Brazil, which border French Guiana. This potential for transmission could seriously threaten the success of malaria elimination programs in the Guiana Shield. Further studies are needed to better evaluate malaria epidemiology in these undocumented populations to determine how best to adapt strategies to control malaria transmission in this subregion of South America. Technical Appendix: The distribution of mosquitoes sampled by sampling sites and Plasmodium infection rates of the 374 Anopheles mosquitoes caught in the French Guiana forest, 2013 Click here to view.(72K, pdf)

The challenge of diagnosing Plasmodium ovale malaria in travellers: report of six clustered cases in french soldiers returning from West Africa

BackgroundPlasmodium ovale is responsible for 5% of imported malaria in French travellers. The clinical and biological features of six clustered cases of P. ovale malaria in an army unit of 62 French soldiers returning from the Ivory Coast are reported.Case reportAll patients were symptomatic and developed symptoms on average 50 days after their return and 20 days after the end of chemoprophylaxis (doxycycline). Clinical features included fever (6/6), mostly tertian (4/6), aches (6/6), nausea (3/6), abdominal pain (2/6), diarrhoea (2/6), or cough (2/6). Thrombocytopaenia was lower than 100,000/mm3 in half the cases only, and the haemoglobin count was normal for all patients. The diagnosis was made after at least three thick and thin blood smear searches. Parasitaemia was always lower than 0.5%. All rapid diagnostic tests were negative for HRP2 and pLDH antigens.DiscussionPlasmodium ovale malaria is currently a problem to diagnose in travellers, notably in French soldiers returning from the Ivory Coast. Early attempts at diagnosis are difficult due to the lack of specific clinical features, the rarity of biological changes and the poor sensitivity of diagnostic tools to detect low parasitaemia. Thus, the diagnosis is commonly delayed or missed. Physicians should be aware of this diagnostic challenge to avoid relapses and provide prompt and adequate treatment with chloroquine and radical cure with primaquine.

Plasmodium vivax Malaria among Military Personnel, French Guiana, 1998–2008

We obtained health surveillance epidemiologic data on malaria among French military personnel deployed to French Guiana during 1998–2008. Incidence of Plasmodium vivax malaria increased and that of P. falciparum remained stable. This new epidemiologic situation has led to modification of malaria treatment for deployed military personnel.

Early treatment failure during treatment of Plasmodium falciparum malaria with atovaquone-proguanil in the Republic of Ivory Coast

The increased spread of drug-resistant malaria highlights the need for alternative drugs for treatment and chemoprophylaxis. The combination of atovaquone‐proguanil (Malarone®) has shown high efficacy against Plasmodium falciparum with only mild side-effects. Treatment failures have been attributed to suboptimal dosages or to parasite resistance resulting from a point mutation in the cytochrome b gene. In this paper, a case of early treatment failure was reported in a patient treated with atovaquone-proguanil; this failure was not associated with a mutation in the parasite cytochrome b gene, with impaired drug bioavailability, or with re-infection.

Self-Reporting Compared to Prospective Surveillance to Evaluate the Incidence of Diarrhea Among French Army Personnel Deployed to N’djamena, Chad

Self-reporting seems more appropriate than medical-based surveillance to estimate true incidence of diarrhea during deployment of military troops. Most soldiers self-reported multiple episodes, 42% leading to medical care, mainly the first episode, resulting in a threefold higher incidence. Mathematical models integrating self-reported data should better predict outbreaks during military deployments and define a more complete assessment of disease burden.

Gastrointestinal illnesses among French forces deployed to Djibouti: French military health surveillance, 2005-2009.

Despite an increase in foreign tourism and in the numbers of foreign military personnel deployed to Djibouti, little is known about the risk of gastrointestinal illness in this country in eastern Africa. To assess risk and to describe common features of gastrointestinal illnesses, reports of illness derived from military health surveillance data collected during 2005-2009 among French service members deployed to Djibouti were reviewed. Diarrhea was the most common problem; it had an annual incidence ranging from 260 to 349 cases per 1,000 person-years. The risk was higher among soldiers deployed short-term (four months) than among soldiers deployed long-term (two years). This five-year review of French health surveillance data documents a significant burden of diarrhea among French soldiers in Djibouti. The identification of factors associated with risk may permit efficient targeting of interventions to reduce morbidity from gastrointestinal illness.

A Large Outbreak of Thiamine Deficiency Among Illegal Gold Miners in French Guiana.

From September 2013 to July 2014, several gold miners working in the tropical forest consulted the Maripasoula Health Center in French Guiana for edema and findings consistent with right-sided cardiac failure. Of the 42 cases of beriberi that were diagnosed, one patient died. The laboratory and clinical investigation demonstrated vitamin B1 deficiency in most of the patients tested. Furthermore, 30 of 42 patients responded favorably to 500 mg of intravenous or intramuscular thiamine supplementation. In addition, dietary investigation showed insufficient thiamine intake in these patients. We concluded that patients had acquired beriberi because of diet restrictions, hard labor, and infectious diseases, notably malaria. In 2016, cases were still being reported. We recommend screening for compatible symptoms in gold miners, thiamine supplementation, and nutritional intervention.

Mortality among active-duty male French Armed Forces, 2006-10.

BACKGROUND In the Armed Forces, knowledge about the causes of deaths is required in order to develop prevention strategies. This study presents the main characteristics of causes of deaths among male active-duty personnel in the French Armed Forces during the 2006-10 period and compares them with the general French male population. METHODS The data are provided by military public health surveillance. Comparisons of the specific mortality rates (MR) were performed using a Poisson regression. Standardized mortality ratios (SMRs) were calculated to compare mortality with the general French male population. RESULTS There were 1455 deaths among male active-duty personnel during the study period [MR: 100.9 per 100,000 person-years (PY); 95% confidence interval 95.7-106.1]. The 17-24 age group was characterized by violent deaths: transport accident (MR: 45.9 per 100,000 PY) and suicide (18.8 per 100 000 PY). Overall SMRs show significantly lower MR compared with the French national MR with the exception of SMR for transport accident and suicide in the 17-24 age group. CONCLUSIONS There is a significantly lower deficit of mortality compared with the French male general population, reflecting a strong healthy worker effect. However, health promotion programmes should continue to put emphasis on transport accident especially among the 17-24 age group.