Case Report: "Killer Bee" Swarm Attacks in French Guiana: The Importance of Prompt Care.

In French Guiana, a French overseas region partly located in the Amazon, "Africanized" bees, a hybrid species of Brazilian bees known as "killer bees," have been observed since 1975. Since then, several cases requiring long hospitalization times have been described, allowing for a better understanding of the physiopathological mechanisms of this particular envenomation. Here, we report on a series of 10 cases of patients simultaneously attacked by hundreds of killer bees and immediately treated by a prehospital medical team already on site. Between 75 and 650 stingers were removed per victim. The reference treatment for anaphylaxis using intramuscular injection of epinephrine, vascular filling, and oxygen therapy was administered to all patients without delay. A clinical description was provided, and biological tests were performed immediately after the envenomation. We therefore observe the existence of a two-phase, medically well-controlled systemic toxic reaction. Thus, all our patients left the hospital after 44 hours of monitoring with no complications or sequelae, despite levels of intoxication described as potentially fatal elsewhere in the literature.

Case Report: Acute Kidney Failure due to Massive Envenomation of a Two-Year-Old Child Caused by Killer Bee Stings.

A hybrid species of Brazilian bee has proliferated on the South American continent since 1956. We describe a "killer bee" swarm attack on a 2-year-old girl in French Guiana. The patient weighed 10 kg, and approximately hundreds of bees' stingers were removed, that is, 10 stings/kg. Our patient survived without long-term sequelae. The management of her condition required admission into intensive care for renal failure due to acute tubular necrosis and severe rhabdomyolysis. We emphasize the importance of early medical intervention, clinical surveillance, and biological monitoring at the hospital to prevent a toxic chain reaction that could prove fatal within 72 hours.

Failure of a Mexican antivenom on recovery from snakebite-related coagulopathy in French Guiana.

INTRODUCTION: In French Guiana, most snakebites are caused by crotalids, with the main signs being tissue damage and bleeding due to venom-induced coagulopathy. Since December 2014 the Western Guiana Hospital (WGH) has used Antivipmyn Tri TM, a Mexican polyvalent antivenom. The aim of the study was to assess its benefit on the correction of snakebite-related coagulopathy. METHODS: This retrospective study included patients hospitalized at the WGH with snakebite and a coagulopathy defined by: a prothrombin rate (PR) lower than 45%, an activated partial thromboplastin time ratio (aPTTr) greater than 2 or a fibrinogen lower than 100 mg.dL-1. The antivenom group included patients receiving Antivipmyn Tri TM from December 2014 to September 2017. The control group included patients admitted between January 2013 and November 2014 (when antivenom was unavailable) or admitted between December 2014 and September 2017 during times of antivenom shortage. We graphically compared the time courses of PR, aPTTr and fibrinogen between groups. Other endpoints were the length of hospital stay and the need for surgery or dialysis. RESULTS: 84 patients were included: 42 in the antivenom group, 42 in the control group. Both groups were similar for age, sex-ratio, proportion of bleedings, necrosis, and severity. Most patients in the antivenom group received 3 vials. There were no significant differences in recovery of PR, aPTTr and fibrinogen through the first 24 h. Fibrinogen declined again in the control group at 30 h and showed a slower rise to normal concentration. There were no significant differences in any secondary endpoint. CONCLUSION: Antivipmyn Tri TM as currently used did not show any benefit in recovery from coagulopathy.

Estimation of the duration between HIV seroconversion and HIV diagnosis in different population groups in French Guiana: Strategic information to reduce the proportion of undiagnosed infections.

BACKGROUND: Given the great efforts put into the strategic objective of reducing the proportion of HIV-infected patients that are undiagnosed, the aim of the present study was to review the temporal trends between 1997 and 2016 for median estimates of infection duration and median CD4 count at diagnosis for the main patient origins in French Guiana. METHODS: CD4 cell count at HIV sero-conversion and square root of CD4 cell decline were obtained using the CD4 decline in a cohort of HIV-infected persons in the UK, fitting random effect (slope and intercept) multilevel linear regression models. Multivariate analysis used robust regression for modeling the delay between estimated HIV seroconversion and diagnosis and quantile regression for CD4 at HIV diagnosis. RESULTS: The median interval between the estimated HIV seroconversion and HIV diagnosis was 8 years for patients fromBrazil, 4.5 years for those from Haiti, 6.6 years for those from Suriname, 3.3 years for patients from Guyana, and 3.1 years for French patients. A simple robust regression model with French patients as reference group adjusting for sex and age at the time of diagnosis showed that the interval was significantly longer for Brazilian (ß = +3.7 years, P = 0.001), Surinamese (ß = +4.2 years, P<0.0001), Haitian origins (ß = +1.5 years, P = 0.049) but not for those originating from Guyana (ß = -0.03 years, P = 0.9); Men independently had a longer interval than women (ß = +3.5 years, P<0.0001). CONCLUSIONS: Despite great efforts in French Guiana regarding HIV testing both in terms of diversification and intensification we still need to tailor the offer to better reach the communities in need. These results should help authorities scale up and optimize initiatives to reduce the proportion of patients who are unaware of their infection. They also raise the question of the role of stigma and discrimination as a barrier to HIV testing in small communities, and further emphasize the importance of reducing it.

A new species of the genus Pristimantis (Amphibia, Craugastoridae) associated with the moderately elevated massifs of French Guiana.

We describe a new Pristimantis from French Guiana, northern South America, which is mainly distinguished from known phenotypically related congeners (i.e. species from the polyphyletic unistrigatus species group) occurring at low and middle elevations in the Guiana Shield by the combination of a distinct tympanum, a lower ratio of tibia vs. hand length, a reddish groin region, and a distinct advertisement call consisting of clusters of generally four short notes. The new species inhabits pristine primary forests on the slopes of isolated massifs reaching more than 400 m elevation, and seems not to occur below ca. 200 m above sea level. Such a sharp altitudinal limit suggests a strong influence of thermal variation on the distribution of the species, and therefore a potential sensitivity to climate change. With only nine isolated populations documented so far, the new species should be prioritized for conservation. Historical climate fluctuations during the Quaternary are likely responsible for the distribution pattern of the new species. 

Increased incidence of leprosy following HAART initiation: a manifestation of the immune reconstitution disease.

A retrospective cohort study was conducted to determine whether the incidence of leprosy varied with the duration of antiretroviral therapy (ART). Between 1992 and 2006, seven cases of leprosy were observed. The incidence of leprosy in untreated patients was 0.7 per 1000 person-years, 13 per 1000 person-years in persons receiving HAART for more than 3 months and 0.9 per 1000 person-years for persons receiving HAART for more than 3 months. The adjusted hazard ratio was 18.5 (95% confidence interval, 1.6-217) with P = 0.02. In tropical areas where HAART is increasingly available, physicians should be aware of the possibility of incident leprosy shortly after HAART initiation.

Underestimation of species richness in neotropical frogs revealed by mtDNA analyses.

BACKGROUND: Amphibians are rapidly vanishing. At the same time, it is most likely that the number of amphibian species is highly underestimated. Recent DNA barcoding work has attempted to define a threshold between intra- and inter-specific genetic distances to help identify candidate species. In groups with high extinction rates and poorly known species boundaries, like amphibians, such tools may provide a way to rapidly evaluate species richness. METHODOLOGY: Here we analyse published and new 16S rDNA sequences from 60 frog species of Amazonia-Guianas to obtain a minimum estimate of the number of undescribed species in this region. We combined isolation by distance, phylogenetic analyses, and comparison of molecular distances to evaluate threshold values for the identification of candidate species among these frogs. PRINCIPAL FINDINGS: In most cases, geographically distant populations belong to genetically highly distinct lineages that could be considered as candidate new species. This was not universal among the taxa studied and thus widespread species of Neotropical frogs really do exist, contrary to previous assumptions. Moreover, the many instances of paraphyly and the wide overlap between distributions of inter- and intra-specific distances reinforce the hypothesis that many cryptic species remain to be described. In our data set, pairwise genetic distances below 0.02 are strongly correlated with geographical distances. This correlation remains statistically significant until genetic distance is 0.05, with no such relation thereafter. This suggests that for higher distances allopatric and sympatric cryptic species prevail. Based on our analyses, we propose a more inclusive pairwise genetic distance of 0.03 between taxa to target lineages that could correspond to candidate species. CONCLUSIONS: Using this approach, we identify 129 candidate species, two-fold greater than the 60 species included in the current study. This leads to estimates of around 170 to 460 frog taxa unrecognized in Amazonia-Guianas. SIGNIFICANCE: As a consequence the global amphibian decline detected especially in the Neotropics may be worse than realised.

Revealing cryptic diversity using molecular phylogenetics and phylogeography in frogs of the Scinax ruber and Rhinella margaritifera species groups.

Few studies to date have examined genetic variability of widespread tropical amphibian species over their distributional range using different kinds of molecular markers. Here, we use genetic data in an attempt to delimit evolutionary entities within two groups of Neotropical frogs, the Scinax ruber species group and the Rhinella margaritifera species group. We combined mitochondrial and nuclear markers for a phylogenetic (a total of approximately 2500 bp) and phylogeographic study (approximately 1300 bp) to test the reliability of the currently accepted taxonomic assignments and to explore the geographic structure of their genetic variation, mainly based upon samples from the French Guianan region. Phylogenetic analyses demonstrated the polyphyly of Scinax ruber and Rhinella margaritifera. S. ruber consists of six lineages that may all merit species status. Conflicting signals of mitochondrial and nuclear markers indicated, among some Scinax lineages and species, the possibility of ongoing hybridization processes. R. margaritifera consisted of 11 lineages which might represent distinct species as well. Phylogeographic analyses added further information in support of the specific status of these lineages. Lineages of low divergence were found in sympatry and were reciprocally monophyletic for mitochondrial as well as nuclear genes, indicating the existence of young lineages that should be awarded species status. Our results highlight the utility of combining phylogenetic and phylogeographic methods, as well as the use of both mitochondrial and nuclear markers within one study. This approach helped to better understand the evolutionary history of taxonomically complex groups of species. The assessment of the geographic distribution of genetic diversity in tropical amphibian communities can lead to conclusions that differ strongly from prior analyses based on the occurrence of currently recognized species alone. Such studies, therefore, hold the potential to contribute to a more objective assessment of amphibian conservation priorities in tropical areas.

Phylogenetic relationships and biodiversity in Hylids (Anura: Hylidae) from French Guiana.

We evaluated two biodiversity criteria, higher taxonomic diversity and phylogenetic diversity in French Guiana. For this, we used a recent assessment of the knowledge accumulated since 30 years of study on the amphibian species currently known in French Guiana. We focused on two well-represented genera, Hyla and Scinax, belonging to the subfamily Hylinae. We used partial sequences of two mitochondrial genes (16S rDNA and 12S rDNA, 813 bp) and two nuclear genes (tyrosinase and 18S rRNA, 1590 bp) covering a total of 2403 bp. According to the high bootstrap support in phylogenetic analysis of the complete dataset, the genus Scinax is a homophyletic clade formed by two species groups (rubra and rostrata) in French Guiana. The genus Hyla was confirmed to be a paraphyletic group formed by two species groups as well (30 chromosomes and the 'gladiator frogs'). We confirmed that these genera should be taxonomically reconsidered. Moreover, at the genus, subfamily and family levels, the use of only morphological characters or only molecular DNA markers would hamper estimations of biodiversity. Thus, we strongly advise the combined use of both morphology and molecular data (nuclear and mitochondrial markers).

Nosocomial nasal myiasis owing to Cochliomyia hominivorax: a case in French Guiana.

Abstract The larval stages of the fly Cochliomyia hominivorax are responsible for myiasis, which primarily affects wounds. We report the case of a bed-ridden patient with dementia who developed right nasal myiasis during his stay at Cayenne Hospital. Progression was favorable, but the nasal pyramid was partially destroyed. In zones where this fly is endemic, particular attention should be given to hospitalized patients with wounds and consciousness problems.

Functional characterization of human Tc0, Tc1 and Tc2 CD8+ T cell clones: control of X4 and R5 HIV strain replication.

CD8(+) T lymphocytes have the potential ability to inhibit human immunodeficiency virus (HIV) replication, by secreting soluble(s) factor(s) known as CD8(+) T lymphocyte antiviral factor (CAF). A panel of CD8(+) and CD4(+) T cell clones from HIV1-infected and uninfected donors were generated to better define the phenotype of CAF-producing cells. We first verified that the different CD4(+) T cell subsets (Th0, Th1, and Th2) were productively infected by X4 and R5 virus strains. X4 viral replication in CD4(+) T cells was controlled by the three CD8(+) T cell subsets (Tc0, Tc1, and Tc2); however, the frequency of Tc clones controlling R5 strain was much lower with a dramatic absence of this activity among Tc clones from uninfected donor. Finally, capacity to control viral replication showed an heterogeneity: some clones could control both virus strains, some controlled only the X4 virus, whereas the majority exerted no suppressive activity.

Molecular phylogeny of French Guiana Hylinae: implications for the systematic and biodiversity of the Neotropical frogs.

In this study we used nucleotide sequences from a segment of mitochondrial 16S ribosomal DNA gene to investigate the evolutionary relationships of some French Guiana Hylinae. New sequences, representing the members of different French Guiana frogs-five specimens of the Scinax genus, two Hyla, one Osteocephalus, one Hyalinobatrachium and two Rana as out-group-were examined. In addition, 26 sequences available from GenBank database representing the other subfamilies of the Hylidae were added to our study. This work allowed us to clarify relationships within the four hylids subfamilies (Pelodryadinae, Phyllomedusinae, Hemiphractinae and Hylinae) and the phylogenetic placement of the enigmatic Scinax genus within the Hylidae. We found that: (1) the Scinax genus displays a high level of differentiation in comparison to two other genera (Litoria and Hyla) belonging to 'Hylidae' family; (2) the Hylinae are paraphyletic given the position of the Litoria, which was the sister-group of the Hyla and the Osteocephalus genera; (3) the anterior works and our results (based on two different data sets) showed the paraphyly of the Hylidae questioning the validity of this family; (4) the reassessment of these different taxonomic groups will induce a huge implication on the estimation (past, present and future) of the biodiversity (in Neotropical frogs).

First seroepidemiological study and phylogenetic characterization of human T-cell lymphotropic virus type I and II infection among Amerindians in French Guiana.

We investigated the serological, epidemiological and molecular aspects of human T-cell lymphotropic virus type I and II (HTLV-I/II) infection in the Amerindian populations of French Guiana by testing 847 sera. No HTLV-II antibodies were detected, but five individuals (0.59%) were seropositive for HTLV-I. Analysis of the nucleotide sequences of 522 bp of the env gene and the compete LTR showed that all of the strains from French Guiana belonged to the cosmopolitan subtype A. The similarities were greater between Amerindian and Creole strains than between Amerindian and Noir-Marron strains or than between Creole and Noir-Marron strains. Phylogenetic analysis showed two clusters: one of strains from Amerindians and Creoles, which belong to the transcontinental subgroup, and the other of strains from Noirs-Marrons, belonging to the West African subgroup. Our results suggest that the Amerindian HTLV-I strains are of African origin.