Etiology of Acute Febrile Illnesses in Adults in the Defense Community in French Guiana.

In tropical countries, acute febrile illnesses represent a complex clinical problem for general practitioners. We describe the prevalence of different etiologies of acute febrile illnesses occurring among French service members and their families, excluding children, in general practice in French Guiana. From June 2017 to March 2020, patients with a fever ≥37.8°C with a duration of less than 15 days who sought medical care at the army medical centers in Cayenne and Kourou were prospectively enrolled. Based on clinical presentation, blood, urine, nasopharyngeal, and stool samples were collected for diagnostic testing for viruses, bacteria, and parasites (by direct examination, microscopic examination of blood smears, culture, serology, or polymerase chain reaction), and standardized biological tests were systematically performed. Among 175 patients retained for analysis, fever with nonspecific symptoms was predominant (46.9%), with 10 Plasmodium vivax malaria cases, 8 dengue infections, and 6 cases of Q fever. The second most frequent cause of acute febrile illness was upper respiratory tract infections (32.0%) due to influenza virus (n = 18) or human rhinovirus (n = 10). Among the causes of acute febrile illness in French Guiana, clinicians should first consider arboviruses and malaria, as well as Q fever in cases of elevated C-reactive protein with nonspecific symptoms and influenza in cases of signs and symptoms associated with upper respiratory tract infections. Despite an expanded microbiological search, the etiology of 51.4% of acute febrile illnesses remain unknown. Further investigations will be necessary to identify the etiology of acute febrile illnesses, including new pathogens, in French Guiana.

Noninvasive detection of Zika virus in mosquito excreta sampled from wild mosquito populations in French Guiana.

Arboviruses can be difficult to detect in the field due to relatively low prevalence in mosquito populations. The discovery that infected mosquitoes can release viruses in both their saliva and excreta gave rise to low-cost methods for the detection of arboviruses during entomological surveillance. We implemented both saliva and excreta-based entomological surveillance during the emergence of Zika virus (ZIKV) in French Guiana in 2016 by trapping mosquitoes around households of symptomatic cases with confirmed ZIKV infection. ZIKV was detected in mosquito excreta and not in mosquito saliva in 1 trap collection out of 85 (1.2%). One female Ae. aegypti L. (Diptera: Culicidae) was found with a ZIKV systemic infection in the corresponding trap. The lag time between symptom onset in a ZIKV-infected individual living near the trap site and ZIKV detection in this mosquito was 1 wk. These results highlight the potential of detection in excreta from trapped mosquitoes as a sensitive and cost-effective method to non invasively detect arbovirus circulation.

Updated estimation of cutaneous leishmaniasis incubation period in French Guiana.

BACKGROUND: The cutaneous leishmaniasis (CL) incubation period (IP) is defined as the time between parasite inoculation by sandfly bite and the onset of the first CL lesion. IP distribution is difficult to assess for CL because the date of exposure to an infectious bite cannot be accurately determined in endemic areas. IP current estimates for CL range from 14 days to several months with a median around 30-60 days, as established by a few previous studies in both New and Old Worlds. METHODOLOGY: We estimated CL incubation period distribution using time-to-event models adapted to interval-censored data based on declared date of travels from symptomatic military personnel living in non-endemic areas that were exposed during their short stays in French Guiana (FG) between January 2001 and December 2021. PRINCIPAL FINDINGS: A total of 180 patients were included, of which 176 were men (97.8%), with a median age of 26 years. When recorded, the parasite species was always Leishmania guyanensis (31/180, 17.2%). The main periods of CL diagnosis spread from November to January (84/180, 46.7%) and over March-April (54/180, 30.0%). The median IP was estimated at 26.2 days (95% Credible Level, 23.8-28.7 days) using a Bayesian accelerated failure-time regression model. Estimated IP did not exceed 62.1 days (95% CI, 56-69.8 days) in 95% of cases (95th percentile). Age, gender, lesion number, lesion evolution and infection date did not significantly modify the IP. However, disseminated CL was significantly associated with a 2.8-fold shortening of IP. CONCLUSIONS: This work suggests that the CL IP distribution in French Guiana is shorter and more restricted than anticipated. As the incidence of CL in FG usually peaks in January and March, these findings suggest that patients are contaminated at the start of the rainy season.

Mayaro virus infection in French Guiana, a cross sectional study 2003-2019.

Mayaro Virus is an emerging arbovirus which can be responsible of important outbreaks in tropical regions. A retrospective study was performed in French Guiana, an ultraperipheral region of Europe in Amazonia. We identified 17 human cases between 2003 and 2019. The clinical and biological picture was close to Chikungunya with fever and arthralgia. One patient had acute meningo-encephalitis, and 4 had persistent arthralgia. Physicians should be aware of this virus, as imported cases in Europe have already occurred. AUTHOR SUMMARY: Latin America has experienced several epidemics of arboviruses in recent years, some known for a long time, such as the dengue virus, and others of more recent introduction such as the chikungunya or Zika viruses. There are other arboviruses for the moment more discreet which are rife with low noise in several countries of the continent, such as the Mayaro virus. This alphavirus, with a presentation similar to that of the chikungunya virus, is currently confined to transmission by forest mosquitoes, but its potential to be transmitted by coastal mosquitoes such as Aedes aegypti, make it a potential candidate for a continent-wide epidemic. It therefore seems necessary to know this virus as well as possible in order to anticipate the occurrence of a possible new epidemic. We present here a both demographic and clinical study of this endemic arbovirus disease in French Guiana.

Cryptosporidiosis outbreak in Amazonia, French Guiana, 2018.

BACKGROUND: Cryptosporidiosis outbreaks in South America are poorly documented. In March 2018, 51 cases of cryptosporidiosis were reported in Maripasoula, a village located in a remote forest area along the border between Surinam and French Guiana. METHOD: To identify the origin of the epidemic, we performed epidemiological, microbiological, and environmental investigations. Only the cases involving diarrhoea and Cryptosporidium-positive stool were considered as bona fide, while cases involving diarrhoea and close contact with a confirmed case were classified as "possible". RESULTS: We identified 16 confirmed cases and 35 possible ones. Confirmed cases comprised nine children (median age of 18 months, range: 6-21), one immunocompromised adult and six soldiers. One child required a hospitalisation for rehydration. All 16 Cryptosporidium stools were PCR positive, and sequencing of the gp60 gene confirmed only one Cryptosporidium hominis subtype IbA10G2. Tap water consumption was the only common risk factor identified. Contamination of the water network with Cryptosporidium parvum subtype IIdA19G2 was found. CONCLUSION: Water quality is a major public health issue in Amazonian French Guiana, especially for population at risk (children, people with comorbidity, travelers). For them, alternative water supply or treatment should be implemented.

Capybara and Brush Cutter Involvement in Q Fever Outbreak in Remote Area of Amazon Rain Forest, French Guiana, 2014.

We investigated a Q fever outbreak that occurred in an isolated area of the Amazon Rain Forest in French Guiana in 2014. Capybara fecal samples were positive for Coxiella burnetii DNA. Being near brush cutters in use was associated with disease development. Capybaras are a putative reservoir for C. burnetii.

Discriminating Tonate Virus from Dengue Virus Infection: A Matched Case-Control Study in French Guiana, 2003-2016.

Tonate virus (TONV) is an arbovirus discovered in 1973 in French Guiana (FG) belonging to the Venezuelan equine encephalitis virus complex, Alphavirus genus. Only few publications and cases have been reported in FG. The objectives of the present study were to describe the clinical picture of TONV and to compare its presentation with that of dengue virus (DENV). A retrospective study was performed in Cayenne hospital from 2003 to 2016 including all patients exclusively positive for TONV IgM and not for other alphaviruses. They were classified as high probability: typical clinical picture of arbovirus infection (i.e., fever, chills, headaches, muscle, and joint pains) and IgM seroconversion; medium probability: typical clinical picture + single positive IgM on a unique serum sample without control; and low probability: atypical clinical picture of infection and single positive IgM. Only patients with high and medium probability were included in the analysis and compared with a gender- and age-matched control group of DENV diagnosed by NS1 antigen (two controls per case). During the study period, 45 cases of TONV were included and compared with 90 cases of DENV. Twenty-eight (62.2%) were men; the median age was 34 years (IQ [22-49]). In the bivariate analysis, variables significantly associated with TONV versus DENV were the presence of cough (33.3% versus 10.3%) and anemia (32.5% versus 11.1%) and the absence of nausea (4.4% versus 32.2%), rash (2.2% versus 27.4%), fatigue (17.8% versus 41.0%), anorexia (6.7% versus 30.1%), muscle pain (42.2% versus 61.4%), headache (53.3% versus 70.8%), leukopenia (9.8% versus 44.4), and lymphopenia (42.5% versus 89.9%). There were no cases with severe neurological involvement, and there were no deaths. Tonate virus may be evoked as a cause of fever in patients living or returning from the Amazonian area. Positive TONV IgM does not prove the diagnosis and should not preclude from searching for alternative infectious diagnoses.

Investigation of a possible malaria epidemic in an illegal gold mine in French Guiana: an original approach in the remote Amazonian forest.

BACKGROUND: In April 2017, Suriname's Ministry of Health alerted French Guiana's Regional Health Agency (RHA) about an increase of imported malaria cases among people coming from an illegal gold mining site called Sophie, in French Guiana, a French overseas territory located in the Amazonian forest. METHODS: Due to safety issues and the remoteness of Sophie, the RHA requested the collaboration of the French Armed Forces for the epidemiological investigation. A medical unit, and six soldiers to ensure the security of the mission, were transported by helicopter. RESULTS: During the investigation, two malaria episodes were diagnosed among 46 persons. Twenty-six of them were from Sophie, where PCR-Plasmodium prevalence was estimated at 60% (15/26). This result was concordant with previous studies revealing high malaria endemicity in the gold miner population. The increase of imported cases in Suriname may have resulted from decreased access to under-the-counter anti-malarials and increased migration of gold miners to Suriname following a decline of the profitability of gold mining in a context of increased repression against illegal mining by the French army. CONCLUSION: This investigation of a suspicious malaria epidemic confirms the importance of malaria among illegal gold miners. Their mobility along the Guiana Shield and their health-seeking behaviour are likely to spread malaria in populations for which significant efforts are undertaken to fight against this disease. Fighting malaria in this population remains more relevant than ever. A pilot study (Malakit project) is currently in progress to evaluate the efficacy of kits for self-diagnosis and self-treatment.

Evolution of symptoms and quality of life during Zika virus infection: A 1-year prospective cohort study.

BACKGROUND: Although the complications of Zika virus infection have been well described, the clinical pattern has not been reported in enough detail to differentiate this infection from those with other arboviroses, and no longitudinal study has yet been published on the persistence of symptoms and quality of life. OBJECTIVES: were to describe bio-clinical pattern and quality of life during ZIKV infection, and their evolution. STUDY DESIGN: We present a 1-year clinical follow-up of 49 people infected with Zika virus in French Guiana, for whom the diagnosis was confirmed by RT-PCR in serum or urine. RESULTS: Fever was inconsistent (95% confidence interval (CI), 39-67). Exanthema (CI, 84-100) was maculopapular, with pruritus and conjunctivitis, variable over time and disappeared 12 days after the onset of symptoms (CI, 10-14). Joint pain (CI, 39-67) occurred mainly in the hands, wrists, knees and ankles and lasted for 10 days (CI, 7-13). Asthenia (CI, 61-85) scored low (3/10) but lasted for 19 days (CI, 16-22). The last two symptoms strongly limited patients' activities in the acute stage of the disease (RAPID-3 score, CI, 5-8). None of the patients had neurological complications, but 41% (CI, 27-55) had areflexia during the first month. CONCLUSIONS: We found no real chronic evolution or decreased quality of life, function or ability to work from the first month after symptom onset.

Dengue surveillance in the French armed forces: a dengue sentinel surveillance system in countries without efficient local epidemiological surveillance.

Surveillance of travel-acquired dengue could improve dengue risk estimation in countries without ability. Surveillance in the French army in 2010 to 2011 highlighted 330 dengue cases, mainly in French West Indies and Guiana: DENV-1 circulated in Guadeloupe, Martinique, French Guiana, New Caledonia, Djibouti; DENV-3 in Mayotte and Djibouti; and DENV-4 in French Guiana.

A cluster of acute diarrhea suspected to be cholera in French travelers in Haiti, December 2010.

A cluster of 21 cases of watery diarrhea suspected to be cholera that involved French military policemen and young volunteers occurring in the context of the Haiti cholera outbreak is described. The attack rate (AR) was higher among young volunteers (71.4%) than among policemen (15.3%) (p < 0.0001). There was a significant association between raw vegetables consumption and watery diarrhea in the young volunteer group. If we consider the raw vegetables consumers only, AR was lower among doxycycline-exposed subjects (relative risk: 0.2; 95% confidence interval: 0.1-0.4). The main aspect that is of scientific interest is the potential prophylactic effect of doxycycline used for malaria prophylaxis on the watery diarrhea AR.