Deciphering environmental forcings in the distribution of meiofauna and nematodes in mangroves of the Atlantic-Caribbean-East Pacific and Indo-West Pacific regions

Mangroves develop under environmental conditions and anthropogenic pressures whose impact on benthic meiofauna remains poorly understood. It is unclear how meiofauna communities are structured according to local sedimentary conditions. This study was designed to characterize the community structure of meiofauna and nematodes (dominant taxa) and the associated environmental forcings in intertidal mangrove sediments from Mayotte (Indo-West-Pacific), Martinique and Guadeloupe (Caribbean). Sediment cores were sampled at the end of the dry season at low tide on adult mangrove stands with similar immersion time. In each sediment layer, we analyzed redox potential, pH, porewater salinity, grain size, organic matter, metals, organic contaminants, prokaryotes and meiofauna. Our results show that sediments far from cities and agricultural fields trapped site-specific contaminants due to local water transport processes. Some metals, PAHs or pesticides exceeded toxicity thresholds in most of the studied stations, thus being harmful to benthic fauna. The sedimentary environment acts as a filter selecting specific meiofauna communities at station scale only in the Caribbean. In Mayotte, horizontal homogeneity contrasts with vertical heterogeneity of the sedimentary environment and the meiofauna. Nematode genera showed particular distribution patterns horizontally and vertically, suggesting the presence of sediment patches suitable for a restricted pool of genera on each island. Results in the Caribbean are consistent with nested diversity patterns due to environmental filtering. Conversely, horizontal homogeneity at Mayotte would reflect greater dispersal between stations or more spatially homogeneous anthropogenic pressures. The nematode genera present at depth may not be the most specialized, but the most versatile, capable of thriving in different conditions. Terschellingia and Daptonema showed contrasted responses to environmental forcing, likely due to their versatility, while Desmodora showed uniform responses between study areas, except when toxicity thresholds were exceeded. Our results emphasize that a given genus of nematode may respond differently to sedimentary conditions depending on sites.

A current overview of the pharmacological composition of "La Chimique" consumed in Mayotte: Preliminary results of the CHASSE-MAREE protocol

Mayotte Island, a French department located in the Mozambique Channel, has for several years been faced with the consumption of "La Chimique" (LC), reputed (but extremely poorly documented) to be a mixture of tobacco and synthetic cannabinoid receptor agonists (SCRAs). One of the objectives of the CHASSE-MAREE protocol is to assess the composition and heterogeneity of LC products through successive LC sample collection campaigns among users. Currently underway, we present here the first analytical results (samples collected in 2022). Between September and December 2022, 80 samples were collected throughout the island over three periods: 70 in the usual form of LC (small folded papers containing a plant-like sample, mostly tobacco), 6 powders, and 4 cigarettes. Analysis was performed using liquid chromatography with high-resolution mass spectrometry. The detected substances (number of detections) included SCRAs (MDMB-4en-PINACA [35], ADB-FUBIATA [25], MDMB-INACA [16], ADB-BUTINACA [15], AFUBIATA [11], 4F-MDMD-BICA [7], CH-PIATA [14], 5C-APINACA [3], BZO-HEXOXIZID [2], and 4F-ABINACA [1]), nicotine (68), tetrahydrocannabinol (THC), cannabinol (CBN), and cannabidiol (CBD) (2), medications (amantadine [11], cyamemazine [6], and acetaminophen [3]), and a designer benzodiazepine (bromazolam [4]). The SCRAs currently in use are varied, and the market for "cooks" (those who prepare LC) is dispersed according to where and when samples are collected. These preliminary results will be supplemented by analysis of samples collected in the first half of 2023 and by an improved description of the current panorama of consumption of LC in Mayotte (mapping, effects felt and dependence, etc.).

Diagnosing psychopathy in an intercultural setting: Applications and implications in postcolonial contemporary Mayotte

International scientific research has extensively studied psychopathy, but few studies focus on an intercultural and postcolonial context. Mayotte, a French overseas collectivity located in East Africa, offers a unique opportunity to study the application and effects of psychopathy diagnosis in the criminal justice field within a social context shaped by colonial legacy. This research uses a mixed-method approach, combining quantitative and qualitative data, to show that in Mayotte, the majority of individuals diagnosed with psychopathy are young, low-income individuals who act in groups. Among them are minors, and the majority have no prior criminal history. This article provides a complementarist reflection on this phenomenon, informed by immersive field anthropology and theoretical contributions from psychology, sociology, and criminology. Through an inductive research process, this study posits the hypothesis that diagnoses of psychopathy in post-colonial contexts may be influenced by complex determinants rooted in collective history and contemporary power relations.

[Determinants of papillomavirus vaccination in Mayotte: A qualitative study among general practitioners]

OBJECTIVES

In Mayotte, cervical cancer represents the second cause of cancer mortality in women. Vaccination coverage against papillomavirus and screening rates are difficult to quantify but among the lowest in France. Added to this is an under-calibrated health system, which does not allow optimal treatment of cancers on site. The objective of the study was to study the elements that would increase papillomavirus vaccination among general practitioners.

METHODS

We carried out a qualitative study of phenomenological inspiration using semi-directed open interviews. The target population was private general practitioners based in Mayotte. The analysis was done by coding verbatim statements, from which emerged general themes, to build a model.

RESULTS

Twenty-two interviews were conducted. Vaccination was part of a context and was organized around the trio doctor-patient-institutions. The main pillar to vaccination was information, which could concern doctors or patients. The information delivered to patients through the media, campaigns in schools, and vaccination obligation were the main elements. The study revealed positive emotional dynamics of on-site HPV vaccination.

CONCLUSION

This study made it possible to better understand the ecosystem in which papillomavirus vaccination takes place in Mayotte, and to identify elements of vaccination promotion. Vaccination school campaigns should keep going on to increase vaccination uptake.

Clinical manifestations of human leptospirosis: bacteria matter

Introduction

A high incidence of human leptospirosis is recorded on Mayotte, an oceanic island located in southwestern Indian Ocean, but the severity of the disease appears relatively mild in terms of mortality rate and admission to the intensive care unit. It has been proposed that mild leptospirosis may result from a limited virulence of some of the occurring Leptospira species to which the population is exposed.

Methods

Clinical and biological data of patients admitted to the Centre Hospitalier de Mayotte were collected and the infecting Leptospira species were determined through molecular typing.

Results

Leptospira interrogans was detected in the minority of admitted patients but most of these patients suffered from severe forms, with 50% admitted to intensive care unit and suffering from organ failures. Nineteen percent of patients infected with Leptospira borgpetersenii were admitted to the intensive care, with 13% displaying organ failures, and one patient died. Leptospira mayottensis was found in 28% of the patients and not a single severe case was observed.

Discussion

The distribution of Leptospira species in patients was not different from that reported 10-15 years ago and bacterial genotypes were very closely related to those previously reported. These results highlight the importance of the diversity of pathogenic Leptospira circulating on Mayotte island and are in keeping with distinct outcome of the disease depending on the infecting Leptospira. Altogether, presented data support that the infecting Leptospira species is an important driver of disease severity in humans.

[Mayotte, a malaria-free island at last?]

Mayotte is a French overseas department and one of the 4 islands of the Comoros archipelago in the Indian Ocean, located between Madagascar and the eastern coast of Africa. Malaria, mainly by Plasmodium falciparum, is endemic to the archipelago and remained a major public health problem until recent years. To control and then eliminate the disease, major strategies have been established in Mayotte since 2001. Preventive measures, diagnostic testing, treatment and disease surveillance were introduced or improved.From 2002 to 2021, 4819 autochthonous cases were reported in Mayotte where the annual incidence decreased from 10.3 per 1,000 population in 2002 (1649 cases) to less than 0.01 per 1,000 population in 2020 (2 cases). The incidence has been below 1 per 1,000 population since 2009. In 2013, WHO classified Mayotte as a territory in malaria elimination phase. In 2021, no locally acquired malaria cases were reported on the island. During this period 2002-2021, 1898 imported cases were observed. They mainly came from the Union of Comoros (85.8%), Madagascar (8.6%) and sub-Saharan Africa (5,6%). Since 2017, the annual number of locally acquired cases was less than 10 and decreased steadily (9 cases in 2017, 5 in 2018, 4 in 2019 and 2 in 2020). The distribution of these rare locally acquired cases both in time and space suggests that they were introduced and not indigenous cases. A study of the genotypic profile of the plasmodial strains of these cases observed from 2017 to 2020 (17 cases analysed out of 20 diagnosed) confirms that these were certainly introduced cases related to imported cases from the neighboring Comoros.Malaria indigenous transmission seems to be eliminated in Mayotte, but the island remains under threat of reintroduction via cases imported from neighbouring countries. It is time to develop a local plan to prevent reintroduction and to implement a proactive policy of regional cooperation in the fight against malaria.

Evidence of Eretmapodites subsimplicipes and Aedes albopictus as competent vectors for Rift Valley fever virus transmission in Mayotte

Rift Valley fever (RVF) recently re-emerged in Mayotte. We described, for the first time, that the mosquito species Eretmapodites subsimplicipes, a highly abundant species in Mayotte, is a competent vector for the transmission of RVF virus using three distinct populations native to Mayotte. We also showed that Aedes albopictus specimens are able to transmit RVF virus (RVFV) as previously observed in mosquito populations of other countries emphasizing the need of the increase vigilance for this highly invasive species of global distribution. Altogether, these results underline the epidemiological importance of both species for RVFV transmission in Mayotte and contribute to better understand the RVF epidemiological cycle and help to implement efficient prevention measures.

[Pediatric medical evacuations from Reunion Island to metropolitan France]

BACKGROUND

The only French center for pediatric oncology and hematology outside of the metropolitan territory is in the Indian Ocean, in Saint Denis, on Reunion Island. It welcomes children from Reunion Island but also from Mayotte and neighboring countries. A quarter of them requires a secondary medical transfer to metropolitan France for specific technic care.

METHOD

We conducted a retrospective single-center study of all pediatric medical evacuations that occurred between 2015 and 2019 from the pediatric oncology and hematology department of Reunion Island. The purpose of this study is to describe these transfers and the consequences of these care pathways for families and care teams.

RESULTS

A total of 189 transfers took place for 105 children: 66 from Reunion Island, 17 from Mayotte and 22 were foreigners. In total, 92 % of the children received the medical care for which they were transferred to metropolitan France. Difficulties were reported: family for 26 % of them, social in 11 % of cases and medical in 10 % of medical records.

CONCLUSIONS

This organization allows children in the Indian Ocean to benefit from similar care than metropolitan children. Many difficulties arise in connection with family and societal breakdowns caused by these transfers. These differences and difficulties are important to know to better accompany patients, families and caregivers in this stage of their medical pathways.

SARS-CoV-2 with Panton-Valentine leukocidin-producing Staphylococcus aureus healthcare-associated pneumonia in the Indian Ocean

At this time, the literature reports only one case of superinfection with Panton-Valentine leukocidin (PVL)-producing Staphylococcus aureus in a patient with severe acute respiratory distress syndrome secondary to coronavirus 2 (SARS-CoV-2) pneumonia. Here we report the first two cases of PVL-producing S. aureus healthcare-associated pneumonia in patients hospitalized for SARS-CoV-2 pneumonia in the Indian Ocean region. The two isolated strains of S. aureus were found to belong to the ST152/t355 clone, a known PVL-producing S. aureus clone that circulates in Africa and is responsible for infections imported into Europe. Our two cases reinforce the hypothesis that SARS-CoV-2 infection favors the occurrence of PVL-producing S. aureus pneumonia. Production of PVL should be searched in patients returning from the Indian Ocean region who present with severe SARS-CoV-2 pneumonia complicated by superinfection with S. aureus even in the case of late onset healthcare-associated pneumonia

Hepatitis B, C, and delta in the general population in Mayotte: hepatitis B as a major public health concern

BACKGROUND

Located in southwestern Indian Ocean, Mayotte is a French territory, with a very specific demographic, social and health context. To date, epidemiological data on infections by hepatitis B (HBV), C (HCV), and delta (HDV) viruses in Mayotte have been sparse. We aimed to estimate, in the 15-69-year-old general population living in Mayotte, the prevalence of infections by hepatitis B (HBV), C (HCV), and delta (HDV) viruses and the distribution of HBV status: current infection with positive HBs antigen (Ag); resolved infection with positive HBc antibodies and negative HBsAg; immunisation by vaccination with only positive HBs antibodies; and no infection/no immunisation with negative markers. We also described the characteristics of infected people and assessed the determinants of lifetime HBV infection.

METHODS

The Unono Wa Maore survey, implemented in a random sample of the general population in 2018-2019, consisted of an at-home collection of epidemiological data and venous blood samples. Detection of hepatitis B, C, and delta serological and molecular markers was performed.

RESULTS

Among 5207 eligible people, 4643 responded to the questionnaire (89.2%), with 2917 being tested for HBV and HCV (62.8%). Estimated HBV status was as follows: current infection 3.0% (95% confidence interval [CI]: 2.3-3.9%) (n = 76); resolved infection 27.8% (95% CI: 25.8-29.9); immunisation by vaccination 27.7% (95% CI: 25.9-29.7); and no infection/no immunisation 41.5% (95% CI: 39.3-43.7). One participant was positive for HDV antibodies (Ab) (0.65%) with a negative HDV-RNA viral load. The risk of lifetime HBV infection was higher in men (adjusted prevalence ratio (aPR): 1.55, 95% CI: 1.29-1.89); in people aged 30-49 years (aPR: 3.83, 95% CI: 1.49-9.81) or 50-69 years (aPR: 4.52, 95% CI: 1.77-11.53) compared to those under 20; in individuals who reported no condom use during their first sexual intercourse (aPR: 1.46, 95% CI: 1.01-2.14); and in those living in Dembeni-Mamoudzou (aPR: 1.40, 95% CI: 1.09-1.80) compared to the West-Centre of Mayotte. Finally, six individuals were positive for HCV antibodies (0.21%), including three positive for HCV RNA.

CONCLUSIONS

Mayotte is an area of intermediate endemicity for HBV and low endemicity for HCV and HDV. With a prevalence of HBsAg 10 times higher than in mainland France, a high proportion of people susceptible to HBV infection, and a demographic, health, and social context that may favour its transmission, hepatitis B is a major public health concern in Mayotte.

Epidemiological profile of COVID-19 in the French overseas department Mayotte, 2020 to 2021

BackgroundDuring the COVID-19 pandemic, national and local measures were implemented on the island of Mayotte, a French overseas department in the Indian Ocean with critical socioeconomic and health indicators.AimWe aimed to describe the COVID-19 outbreak in Mayotte from March 2020 to March 2021, with two waves from 9 March to 31 December 2020 and from 1 January to 14 March 2021, linked to Beta (20H/501Y.V2) variant.MethodsTo understand and assess the dynamic and the severity of the COVID-19 outbreak in Mayotte, surveillance and investigation/contact tracing systems were set up including virological, epidemiological, hospitalisation and mortality indicators.ResultsIn total, 18,131 cases were laboratory confirmed, with PCR or RAT. During the first wave, incidence rate (IR) peaked in week 19 2020 (133/100,000). New hospitalisations peaked in week 20 (54 patients, including seven to ICU). Testing rate increased tenfold during the second wave. Between mid-December 2020 and mid-January 2021, IR doubled (851/100,000 in week 5 2021) and positivity rate tripled (28% in week 6 2021). SARS-CoV-2 Beta variant (Pangolin B.1.351) was detected in more than 80% of positive samples. Hospital admissions peaked in week 6 2021 with 225 patients, including 30 to ICU.ConclusionThis massive second wave could be linked to the high transmissibility of the Beta variant. The increase in the number of cases has naturally led to a higher number of severe cases and an overburdening of the hospital. This study shows the value of a real-time epidemiological surveillance for better understanding crisis situations.

Hammerhead flatworms (Platyhelminthes, Geoplanidae, Bipaliinae): mitochondrial genomes and description of two new species from France, Italy, and Mayotte

BACKGROUND

New records of alien land planarians are regularly reported worldwide, and some correspond to undescribed species of unknown geographic origin. The description of new species of land planarians (Geoplanidae) should classically be based on both external morphology and histology of anatomical structures, especially the copulatory organs, ideally with the addition of molecular data.

METHODS

Here, we describe the morphology and reproductive anatomy of a species previously reported as Diversibipalium "black", and the morphology of a species previously reported as Diversibipalium "blue". Based on next generation sequencing, we obtained the complete mitogenome of five species of Bipaliinae, including these two species.

RESULTS

The new species Humbertium covidum n. sp. (syn: Diversibipalium "black" of Justine et al., 2018) is formally described on the basis of morphology, histology and mitogenome, and is assigned to Humbertium on the basis of its reproductive anatomy. The type-locality is Casier, Italy, and other localities are in the Department of Pyrénées-Atlantiques, France; some published or unpublished records suggest that this species might also be present in Russia, China, and Japan. The mitogenomic polymorphism of two geographically distinct specimens (Italy vs France) is described; the cox1 gene displayed 2.25% difference. The new species Diversibipalium mayottensis n. sp. (syn: Diversibipalium "blue" of Justine et al., 2018) is formally described on the basis of external morphology and complete mitogenome and is assigned to Diversibipalium on the basis of an absence of information on its reproductive anatomy. The type- and only known locality is the island of Mayotte in the Mozambique Channel off Africa. Phylogenies of bipaliine geoplanids were constructed on the basis of SSU, LSU, mitochondrial proteins and concatenated sequences of cox1, SSU and LSU. In all four phylogenies, D. mayottensis was the sister-group to all the other bipaliines. With the exception of D. multilineatum which could not be circularised, the complete mitogenomes of B. kewense, B. vagum, B. adventitium, H. covidum and D. mayottensis were colinear. The 16S gene in all bipaliine species was problematic because usual tools were unable to locate its exact position.

CONCLUSION

Next generation sequencing, which can provide complete mitochondrial genomes as well as traditionally used genes such as SSU, LSU and cox1, is a powerful tool for delineating and describing species of Bipaliinae when the reproductive structure cannot be studied, which is sometimes the case of asexually reproducing invasive species. The unexpected position of the new species D. mayottensis as sister-group to all other Bipaliinae in all phylogenetic analyses suggests that the species could belong to a new genus, yet to be described.

COVID-19 cluster in vaccinated healthcare workers in Mayotte

We report a significant cluster of SARS-CoV-2 (B.1.617.2 variant) among young healthcare workers (HCW) (median age of 27 years) living in the Mamoudzou interns apartment complex, belonging to the Hospital Center in Mayotte. Among them, 18 developed SARS-CoV-2 infection (62.1%) and all were symptomatic. The infection rate was higher for people who had had a second dose more than 6 months before than for those who had had a second dose less than 6 months before (P = 0.05). This epidemic had no individual consequence, but the hospital functioning in Mayotte was significant impacted. This report reinforces the need for a third dose of vaccine among HCWs, in addition to non-pharmaceutical measures.

Epidemiology of serious bacterial infection in febrile infants under 3 months of age and diagnostic management in Mayotte

OBJECTIVE

This study aimed to determine the prevalence of serious bacterial infections (SBIs) in infants less than 90 days old presenting with fever on arrival at the emergency department (ED), and to assess the diagnostic management of febrile infants.

DESIGN

A retrospective study at Mamoudzou Hospital, Mayotte Island, French Department.

SETTING

General ED in the only pediatric hospital throughout the territory PATIENTS: We included infants less than 90 days old with a history of fever and bacterial investigation evaluated in the ED between 2016 and 2018. We excluded preterm infants (gestational age < 37 weeks) and those with known immunodeficiency or previous administration of antibiotics.

RESULTS

A total of 594 infants were included. In all, 105 infants (17.7%) were diagnosed with an SBI and 28 (4.7%) with an invasive bacterial infection of which 1.34% was meningitis. The most frequent SBI was pneumonia (n = 69, 11.6%) followed by urinary tract infection (UTI; n = 37, 6.2%). Predominant pathogens (excluding contaminants) were Escherichia coli (51.2% of the UTI cases), group B Streptococcus (62.5% of meningitis cases), and Staphylococcus aureus (61.5% of bacteremia cases). Seven infants presented with bacterial pneumonia due to Staphylococcus aureus with Panton-Valentine leucocidin (PVL) exotoxin production. Ill-appearing infants, clinical signs of SBI and complex chronic condition were associated with a risk of SBI (respective odds ratio [OR]: 4.6, 95% confidence interval [CI]: 3-6.9; OR: 4.2, 95% CI: 2.8-6.4; and OR: 3.2, 95% CI: 1.2-8.5). The median age for SBI was 42 days (5-90). Fever without source (FWS) occurred more often in infants under 21 days of age (48.5% vs. 31.3% in older infants, p < 0.001). The median duration of fever at home was 24 h (6-96). Concerning management, in infants aged under 21 days, there were more lumbar punctures (58.3% vs. 23% in older infants, p < 0.001) and more frequent initiation of empiric antibiotics (62.6% vs. 42.7%, p < 0.001). Length of stay was also longer in this age range (5 days vs. 3 days, p = 0.037).

CONCLUSION

Delay in medical consultation in the case of fever, the risk of SBI regardless of age, and unusual epidemiology with many IBI due to Staphylococcus aureus with PVL exotoxin production are specific characteristics observed in our study. Knowledge of the current epidemiology of SBI in Mayotte would be useful for setting up a risk-stratified protocol in this population in the future.

Rift Valley Fever Outbreak, Mayotte, France, 2018-2019

From November 2018 through July 2019, an outbreak of Rift Valley fever in humans occurred in Mayotte, France; 142 cases were confirmed. Exposure to animals or their biological fluid was reported by 73% of patients. Health authorities have been implementing control measures, including veterinary surveys, vector control interventions, and prevention measures.

Multisystem Inflammatory Syndrome Associated With Severe Acute Respiratory Syndrome Coronavirus 2 in Children: A Case Series From Mayotte Island

During the COVID-19 outbreak in the French overseas department Mayotte, 11 children developed multisystem inflammatory syndrome (MIS-C). They all had a fever and gastrointestinal symptoms. Six patients were admitted to intensive care unit; management included intravenous immunoglobulin and corticosteroid. Severe acute respiratory syndrome coronavirus 2 was documented in all patients. The risk of developing MIS-C was much higher than in all of France.

Morphological, osteological, and genetic data support a new species of Madatyphlops (Serpentes: Typhlopidae) endemic to Mayotte Island, Comoros Archipelago

Blind snakes (Typhlopidae) are an enigmatic group of small burrowing snakes whose anatomy, phylogenetics, and biodiversity remain poorly known. Madatyphlops comorensis (Boulenger, 1889), endemic to the Comoros Archipelago in the Western Indian Ocean, is one of many species whose phylogenetic placement and generic assignment is unclear. We used DNA barcoding, external morphological examination, and osteological data from 3D reconstruction with micro-CT to study specimens of Madatyphlops from the Comoros Archipelago. Our results support the placement of M. comorensis in Madatyphlops and the recognition of the specimens from Mayotte Island as a closely related but distinct species, which we describe as Madatyphlops eudelini sp. nov. In this context, we present the first detailed osteological descriptions of any species of Madatyphlops, which we hope will serve as groundwork for further osteological studies in this genus and contribute to our limited but growing understanding of the osteology of typhlopid snakes.

Hidden in plain sight: a new frog species of the genus Blommersia from the oceanic island of Mayotte, Comoros archipelago

The amphibian fauna of the western Indian ocean volcanic island of Mayotte is currently constituted by two species belonging to two genera of the anuran family Mantellidae: Blommersia transmarina and Boophis nauticus. These were recently described after intense fieldwork on the herpetofauna of the island. We here describe a third new species of frog from Mayotte, based on morphological and molecular data, that occurs in sympatry with the others and was utterly unnoticed until now. Genetic analyses of the16S rRNA gene, including all described and several undescribed species of the genus Blommersia from Madagascar and Mayotte, confirms that the new species is the sister species of Blommersia transmarina. Both species show apparent morphological differences as well as different life histories, ecology and genetics that confirm Blommersia nataliae sp. nov. as a new species. We propose an IUCN Red List status of Critically Endangered for B. nataliae sp. nov.

Fungemia in the French department of Mayotte, Indian Ocean: A 10 years survey

OBJECTIVE

This study aimed at providing original data on fungemia in the Centre Hospitalier de Mayotte in terms of prevalence, epidemiological characteristics of infected patients, yeast species distribution and profile of in vitro antifungals susceptibility.

METHODS

A total of 223 positive blood cultures for yeasts were retrospectively reported during the period April 2010-April 2020.

RESULTS

Ninety-five episodes were identified corresponding to an incidence rate of 3.7 cases/100,000 inhabitants. The average age of patients was 33.5 years, and 63.3% patients were hospitalized in intensive care unit. The main co-morbidities were surgery in the 30 days prior to fungemia (27.8%), neoplasia (22.8%), parenteral nutrition (17.7%), diabetes (16.5%) and immunosuppressive medications (31.6%). Candida spp accounted for the majority of isolates (92.4%) with a predominance of non-albicans species (55.8% vs 33.7%), including C. albicans (33.7%), C. tropicalis (30.5%) and C. parapsilosis (20%). The antifungal susceptibility profiles did not differ from expected results for each species and did not change significantly over time.

DISCUSSION

Fungemia remain frequent hospital infections associated with high mortality in Mayotte. The vast majority of fungemia was due to Candida spp. Non-albicansCandida species reach half of the Candida isolates with a high percentage of C. tropicalis. Surprisingly, no case of candidemia due to C. glabrata were identified. The management of candidemia remains satisfactory and the treatment was adapted according to the international recommendations. However, the high susceptibility of Candida spp. isolates to fluconazole may invite to reconsider the use of this molecule as empirical and first-line treatment of candidemia in Mayotte.

Rift Valley Fever - assessment of effectiveness of surveillance and control measures in the EU

Effectiveness of surveillance and control measures against Rift Valley Fever (RVF) in Mayotte (overseas France) and in continental EU were assessed using mathematical models. Surveillance for early detection of RVF virus circulation implies very low design prevalence values and thus sampling a high number of animals, so feasibility issues may rise. Passive surveillance based on notified abortions in ruminants is key for early warning and at present the only feasible surveillance option. The assessment of vaccination and culling against RVF in Mayotte suggests that vaccination is more effective when quickly implemented throughout the population, e.g. at a rate of 200 or 2,000 animals vaccinated per day. Test and cull is not an option for RVF control in Mayotte given the high number of animals that would need to be tested. If the risk of RVFV introduction into the continental EU increases, ruminant establishments close to possible points of disease incursion should be included in the surveillance. An enhanced surveillance on reproductive disorders should be applied during summer in risk areas. Serosurveillance targets of 0.3% animals should be at least considered. RVF control measures possibly applied in the continental EU have been assessed in the Netherlands, as an example. Culling animals on farms within a 20 km radius of detected farms appears as the most effective measure to control RVF spread, although too many animals should be culled. Alternative measures are vaccination in a 50 km radius around detection, ring vaccination between 20 and 50 km and culling of detected farms. The assessment of zoning showed that, following RVFV introduction and considering an R0 = 2, a mean vector dispersal of 10 km and 10 farms initially detected, RVFV would spread beyond a radius of up to 100 km or 50 km from the infected area with 10% or 55% probability, respectively.

Estimations of densities of marine litter on the fringing reefs of Mayotte (France - South Western Indian Ocean) - impacts on coral communities

The present study was carried out at 22 stations located on the fringing reefs of the island of Mayotte inside the perimeter of the Marine Natural Park of Mayotte (PNMM). The average assessment of the number of samples of marine litter (ML) collected at these stations was 3.9 ± 1.3 ML per 500 m² in winter and 3.8 ± 1.1 ML per 500 m² in summer. Plastic ML was dominant, representing approximately 92% of the litter collected at the stations for the two seasons. The majority was plastic ML from fishing gear (lines, nets etc.). Station 18 presented remarkable average densities of 39 ± 4.2 ML per 500 m² for the two seasons and differed from the other stations in that the ML came solely from the catchment areas, with a majority of aluminium ML (56%). Approximately half the coral colonies coming into contact with ML presented an impact dominated by the category of "Broken or abraded colonies", with 25% of the colonies being impacted. The colonies most severely impacted by ML were branch or table corals, with the greatest majority for the present study being of the genus Acropora.

The vaccination coverage in dispensaries on Mayotte Island is lacking for natives and migrants alike

OBJECTIVE

Assessing the vaccination coverage rate in Mayotte dispensaries.

PATIENTS AND METHODS

Prospective study in three dispensaries from June to July 2019.

RESULTS

Of the 162 patients included, 78% (126/162) were natives of the island and 19% (30/162) were from the Comoros Islands. Twenty-three percent (37/162) were up-to-date on their mandatory vaccinations, 45% (73/162) were not and 32% (52/162) had unknown vaccination status. There was no difference in relation to their origin. Some vaccinations were strictly followed (MMR, Hepatitis B…) others were not (HiB, meningitides…). The vaccination coverage rate and its traceability are altogether lacking whatever the age or origin of patients. Efforts must be made in order to increase the vaccination coverage rate among people who, from our experience, do not oppose vaccination in any way.

Acute disseminated encephalomyelitis after dengue

Dengue fever, transmitted by Aedes aegypti mosquitoes, is one of the most common vector-borne disease. Its incidence is increasing steadily worldwide, becoming a major public health problem in the tropical and subtropical zone. Neurological manifestations after dengue are not very common and acute disseminated encephalomyelitis (ADEM) following dengue infections is rare with a few cases documented in literature. Clinical characteristics and typical lesions of ADEM on magnetic resonance imaging (MRI) of brain along with serologic positivity for dengue usually confirm the diagnosis. We report a case of ADEM which developed as a neurological complication of dengue during an epidemic in a 39-year-old woman.

High fetal hemoglobin level is associated with increased risk of cerebral vasculopathy in children with sickle cell disease in Mayotte

Background

Understanding the genetics underlying the heritable subphenotypes of sickle cell anemia, specific to each population, would be prognostically useful and could inform personalized therapeutics.The objective of this study was to describe the genetic modulators of sickle cell disease in a cohort of pediatric patients followed up in Mayotte.

Methods

This retrospective cohort study analyzed clinical and biological data, collected between January1^st2007 and December 31^st2017, in children younger than 18 years.

Results

We included 185 children with 72% SS, 16% Sβ0-thalassemia and 12% Sβ + thalassemia. The average age was 9.5 years; 10% of patients were lost to follow up. The Bantu haplotype was associated with an increase in hospitalizations and transfusions. The alpha-thalassemic mutation was associated with a decrease of hemolysis biological parameters (anemia, reticulocytes), and a decrease of cerebral vasculopathy. The Single Nucleotide Polymorphisms BCL11A rs4671393, BCL11A rs11886868, BCL11A rs1427407 and HMIP rs9399137 were associated with the group of children with HbF > 10%. Patients with HbF > 10% presented a significant risk of early onset of cerebral vasculopathy.

Conclusions

The most remarkable result of our study was the association of SNPs with clinically relevant phenotypic groups. BCL11A rs4671393, BCL11A rs11886868, BCL11A rs1427407 and HMIP rs9399137 were correlated with HbF > 10%, a group that has a higher risk of cerebral vasculopathy and should be oriented towards the hemolytic sub-phenotype.

Challenges to medical ethics in the context of detention and deportation: Insights from a French postcolonial department in the Indian Ocean

Owing to a growing policing of borders, healthcare professionals become increasingly involved in the biopolitical management of migrants' mobility. While their presence on sites of migration control and detention is necessary to ensure migrants' access to healthcare, their role risks being instrumentalized to ensure the sustainability of detention and swiftness of deportations. This article analyses the practice and ethics of midwives' medical expertise in processes of migration control in the French overseas department of Mayotte in the Indian Ocean. Midwives in this setting are required to assess the health of pregnant women intercepted at sea by the police in order to determine whether they can be detained. The article traces how midwives come to be invested with a power to police patients' mobility. In the face of such unwelcome responsibilities, midwives resorted to emotional distancing while suspicion on both sides impeded the possibility of genuine relations of care. The article analyses how midwives framed the ethical dilemmas at hand and examines how they perceived their decision-making responsibility. I argue that midwives are socialized into the logics of border enforcement and gradually brought to implement a minimal version of care as a result of migration control's inroads into care. The article thus questions the function and meaning of biopolitics within migration control and aims at initiating a conversation around the necessary conditions for ensuring medical personnel's independence in these extraordinary care settings. The article draws on a three-months fieldwork completed in Mayotte between mid-April and mid-July 2017 during which I conducted 40 interviews with healthcare professionals in perinatal health services and 15 interviews with officers from stakeholder organizations, from local and international NGOs to health institutions. This article draws in particular on interviews with the medical team that was required to attend to migrant women intercepted at sea by the police.

Rift Valley Fever: risk of persistence, spread and impact in Mayotte (France)

Rift Valley fever (RVF) is a vector-borne disease transmitted by different mosquito species, especially Aedes and Culex genus, to animals and humans. In November 2018, RVF re-emerged in Mayotte (France) after 11 years. Up to the end of October 2019, 126 outbreaks in animals and 143 human cases were reported. RVF mortality was 0.01%, and the number of abortions reported in polymerase chain reaction (PCR)-positive ruminants was fivefold greater than the previous 7 years. Milk loss production in 2019 compared to 2015-2018 was estimated to be 18%, corresponding to an economic loss of around €191,000 in all of Mayotte. The tropical climate in Mayotte provides conditions for the presence of mosquitoes during the whole year, and illegal introductions of animals represent a continuous risk of (re)introduction of RVF. The probability of RVF virus (RVFV) persisting in Mayotte for 5 or more years was estimated to be < 10% but could be much lower if vertical transmission in vectors does not occur. Persistence of RVF by vertical transmission in Mayotte and Réunion appears to be of minor relevance compared to other pathways of re-introduction (i.e. animal movement). However, there is a high uncertainty since there is limited information about the vertical transmission of some of the major species of vectors of RVFV in Mayotte and Réunion. The only identified pathways for the risk of spread of RVF from Mayotte to other countries were by infected vectors transported in airplanes or by wind currents. For the former, the risk of introduction of RVF to continental France was estimated to 4 × 10-6 epidemic per year (median value; 95% CI: 2 × 10-8; 0.0007), and 0.001 epidemic per year to Réunion (95% CI: 4 × 10-6; 0.16). For the latter pathway, mosquitoes dispersing on the wind from Mayotte between January and April 2019 could have reached the Comoros Islands, Madagascar, Mozambique and, possibly, Tanzania. However, these countries are already endemic for RVF, and an incursion of RVFV-infected mosquitoes would have negligible impact.

Four new species of Acalypha L. (Euphorbiaceae, Acalyphoideae) from the West Indian Ocean Region

Four new species of Acalypha (Euphorbiaceae, Acalyphoideae) from the Western Indian Ocean Region, based on morphological and molecular evidence, are described, illustrated, and mapped. Acalypha gillespieae sp. nov., A. leandrii sp. nov. and A. nusbaumeri sp. nov. are endemic to Madagascar, and A. mayottensis sp. nov. is known only from Mbouzi islet (Mayotte), in the Comoros Archipelago. We also describe for the first time in Acalypha the presence of membranous or chartaceous perules covering the axillary buds. Preliminary conservation assessments of the new species are also provided.

Co-circulation and characterization of novel African arboviruses (genus Ephemerovirus) in cattle, Mayotte island, Indian Ocean, 2017

Mayotte is an island located in the Mozambique Channel, between Mozambique and Madagascar, in the South Western Indian Ocean region. A severe syndrome of unknown aetiology has been observed seasonally since 2009 in cattle (locally named "cattle flu"), associated with anorexia, nasal discharge, hyperthermia and lameness. We sampled blood from a panel of those severely affected animals at the onset of disease signs and analysed these samples by next-generation sequencing. We first identified the presence of ephemeral bovine fever viruses (BEFV), an arbovirus belonging to the genus Ephemerovirus within the family Rhabdoviridae, thus representing the first published sequences of BEFV viruses of African origin. In addition, we also discovered and genetically characterized a potential new species within the genus Ephemerovirus, called Mavingoni virus (MVGV) from one diseased animal. Finally, both MVGV and BEFV have been identified in cattle from the same herd, evidencing a co-circulation of different ephemeroviruses on the island. The clinical, epidemiological and virological information strongly suggests that these viruses represent the etiological agents of the observed "cattle flu" within this region. This study highlights the importance of the strengthening and harmonizing arboviral surveillance in Mayotte and its neighbouring areas, including Africa mainland, given the importance of the diffusion of infectious diseases (such as BEFV) mediated by animal and human movements in the South Western Indian Ocean area.

[Plant Traditional Treatment with Acalypha indica Inducing Haemolysis in Patients with G6PD Deficiency: A Frequent Circumstance in Mayotte?]

A traditional treatment by plants with Acalypha indica L. can induce an intravascular haemolysis in patients with a glucose-6-phosphate-dehydrogenase (G6PD) deficiency. This information is poorly diffused in areas where the plant grows, where it is consumed for ethnomedicinal purpose and where G6PD deficiency prevalence is high; as a consequence, the probability of haemolytic accidents is presumably underestimated. It seems frequent in Mayotte according to local recent data reporting. Such accidents were previously only, and on a rare basis, reported in Sri Lanka. It seems necessary, at least in Mayotte, to inform patients, or the patients' relatives, about the potential risk in case of using traditional medicine by plants, in addition to all other circumstances able to induce haemolysis in G6PD deficiency.

Culicoides Latreille in the sun: faunistic inventory of Culicoides species (Diptera: Ceratopogonidae) in Mayotte (Comoros Archipelago, Indian Ocean)

BACKGROUND

The south-west insular territories of the Indian Ocean have recently received attention concerning the diversity of arthropods of medical or veterinary interest. While a recent study highlighted the circulation of Culicoides-borne viruses, namely bluetongue and epizootic hemorrhagic disease, with clinical cases in Mayotte (comprising two islands, Petite-Terre and Grand-Terre), Comoros Archipelago, no data have been published concerning the species diversity of Culicoides present on the two islands.

RESULTS

A total of 194,734 biting midges were collected in 18 sites, covering two collection sessions (April and June) in Mayotte. Our study reports for the first time livestock-associated Culicoides species and recorded at least 17 described Afrotropical species and one undescribed species. The most abundant species during the April collection session were C. trifasciellus (84.1%), C. bolitinos (5.4%), C. enderleini (3.9%), C. leucostictus (3.3%) and C. rhizophorensis (2.1%). All other species including C. imicola represented less than 1% of the total collection. Abundance ranged between 126-78,842 females with a mean and median abundance of 14,338 and 5111 individuals/night/site, respectively. During the June collection, the abundance per night was low, ranging between 6-475 individuals. Despite low abundance, C. trifasciellus and C. bolitinos were still the most abundant species. Culicoides sp. #50 is recorded for the first time outside South Africa.

CONCLUSIONS

Our study reports for the first time the Culicoides species list for Mayotte, Comoros Archipelago, Indian Ocean. The low abundance and rare occurrence of C. imicola, which is usually considered the most abundant species in the Afrotropical region, is unexpected. The most abundant and frequent species is C. trifasciellus, which is not considered as a vector species so far, but its role needs further investigation. Further work is needed to describe Culicoides sp. #50 and to carry on faunistic investigations on the other islands of the archipelago as well as in neighboring countries.

Health monitoring during water scarcity in Mayotte, France, 2017

Background

During the 2016–2017 austral summer, unprecedented water scarcity was observed in the south of Mayotte, French island in the Indian Ocean. Therefore, authorities introduced restrictive measures to save the water of this part of the island. The rationing system affected over 65,000 people, for four months. In order to detect a possible deterioration of the health situation, a strengthened epidemiological surveillance system was set up.

Methods

Surveillance focused on intestinal and skin diseases, which are often associated with a lack of hygiene or poor-quality drinking and bathing water. Three pathologies were monitored: acute diarrhoea, acute gastroenteritis and skin diseases and also, proportion of antidiarrhoeal and rehydration solutions sales in pharmacies. Cases of leptospirosis were also under surveillance. The analyses consisted of comparing the collected data according to the areas that were either affected or not affected by the water restrictions. Comparisons with historical data were also made.

Results

Although none of the surveillance systems were able to demonstrate any impact on skin diseases, they revealed a very sharp increase in the proportion of consultations for acute diarrhoea and gastro-enteritis in the southern area. This was corroborated by a high increase in the sales of antidiarrhoeals and oral rehydration solutions via the sentinel pharmacists in the south of the island compared with those of the north. Comparison with historical data highlighted the occurrence of an unusual situation.

Conclusion

These water restrictions caused a real deterioration in the health status of the inhabitants who were deprived of water.

Evidence of bluetongue and Epizootic Haemorrhagic disease circulation on the island of Mayotte

A cross-sectional study was conducted to explore the epidemiological situation in Mayotte regarding two orbiviruses: Bluetongue virus (BTV) and Epizootic Haemorrhagic Disease virus (EHDV). In all, 385 individual asymptomatic cattle were blood-sampled (one EDTA and one serum tube per animal) between February and June 2016. Antibody (ELISA) and genome prevalence (PCR) was assessed. Almost all the selected cattle showed antibodies against both BTV and EHDV, at 99.5% (CI95% [98.00, 100]) and 96.9% (CI95% [94.5, 98.3]), respectively. Most of the cattle acquired antibodies in their first years of age. EHDV and BTV genomes were detected in 25.2% (CI95% [21.1, 29.8]) and 18.2% (CI95% [14.6, 22.4]) of samples, respectively. Coinfection with BTV and EHDV was observed in 9.4% of samples (CI95% [6.8, 12.7]). Cattle under three years old were more frequently reported as positive for genome detection by PCR than older cattle. Five serotypes of BTV and one serotype of EHDV were identified from eight samples: BTV-4, BTV-9, BTV-11, BTV-15, BTV-19 and EHDV-6, of which some were reported in neighbouring areas. BTV and EHDV both circulate in Mayotte and in its surrounding territories.

Bat Astrovirus in Mozambique

Astroviruses (AstVs) are responsible for infection of a large diversity of mammalian and avian species, including bats, aquatic birds, livestock and humans. We investigated AstVs circulation in bats in Mozambique and Mayotte, a small island in the Comoros Archipelago located between east Africa and Madagascar. Biological material was collected from 338 bats and tested for the presence of the AstV RNA-dependent RNA-polymerase gene with a pan-AstV semi-nested polymerase chain reaction assay. None of the 79 samples obtained from Mayotte bats (Pteropus seychellensis comorensis and Chaerephon pusillus) tested positive; however, 20.1% of bats sampled in Mozambique shed AstVs at the time of sampling and significant interspecific variation in the proportion of positive bats was detected. Many AstVs sequences obtained from a given bat species clustered in different phylogenetic lineages, while others seem to reflect some level of host-virus association, but also with AstVs previously reported from Malagasy bats. Our findings support active circulation of a large diversity of AstVs in bats in the western Indian Ocean islands, including the southeastern African coast, and highlight the need for more detailed assessment of its risk of zoonotic transmission to human populations.

Outbreak of IMI-1 carbapenemase-producing colistin-resistant Enterobacter cloacae on the French island of Mayotte (Indian Ocean)

The spread of carbapenemase-producing Enterobacteriaceae in the Southwest Indian Ocean islands is poorly known. Here we describe an outbreak of colistin-resistant Enterobacter cloacae harbouring bla_IMI-1 in the French overseas department of Mayotte. Between October 2015 and January 2017, all isolates of imipenem-non-susceptible E. cloacae at Mayotte Medical Center and University Hospital of Reunion Island were screened for carbapenemase production. Positive isolates were typed by pulsed-field gel electrophoresis and whole-genome sequencing (WGS)-based multilocus sequence typing (MLST), and all β-lactamase genes were identified by PCR and sequencing. Resistance profiles were determined by agar diffusion and Etest. Genetic support of the bla_IMI-1 gene was determined by WGS. A total of 18 E. cloacae isolates harbouring bla_IMI-1 were detected in 17 patients from Mayotte. Pulsed-field gel electrophoresis (PFGE) analysis showed 16 of the 18 strains to be clonally related and belonging to ST820. Based on clinical data, this outbreak most likely had a community origin. The bla_IMI-1 gene in the 18 isolates was carried by a new variant of an integrative mobile element involving the Xer recombinases, called EcloIMEX-8. The mcr-1-mcr-5 genes were absent from the collection. The isolates belonged to E. cloacae cluster XI, known to be colistin heteroresistant. Here we report the first outbreak of IMI-1-producing Enterobacteriaceae. IMI-1-producers may be underdetected in microbiology laboratories because of their unusual antimicrobial resistance profile (resistant to imipenem but with intermediate resistance to ertapenem and susceptible to extended-spectrum cephalosporins) and the absence of bla_IMI-1 in the panel of genes targeted by molecular diagnostic kits.

Diphtheria in Mayotte, 2007-2015

Epidemiology of diphtheria in the southwestern Indian Ocean is poorly documented. We analyzed 14 cases of infection with toxigenic Corynebacterium diphtheriae reported during 2007–2015 in Mayotte, a French department located in this region. Local control of diphtheria is needed to minimize the risk for importation of the bacterium into disease-free areas.

Effects of domestic effluent discharges on mangrove crab physiology: Integrated energetic, osmoregulatory and redox balances of a key engineer species

Mangroves are increasingly used as biofiltering systems of (pre-treated) domestic effluents. However, these wastewater discharges may affect local macrofauna. This laboratory study investigates the effects of wastewater exposure on the mangrove spider crab Neosarmatium meinerti, a key engineering species which is known to be affected by waste waters in effluent-impacted areas. These effects were quantified by monitoring biological markers of physiological state, namely oxygen consumption, the branchial cavity ventilation rate, gill physiology and morphology, and osmoregulatory and redox balance. Adults acclimated to clean seawater (SW, 32 ppt) and freshwater (FW, ∼0 ppt) were compared to crabs exposed to wastewater for 5 h (WW, ∼0 ppt). Spider crabs exposed to WW increased their ventilation and whole-animal respiration rates by 2- and 3-fold respectively, while isolated gill respiration increased in the animals exposed to FW (from 0.5 to 2.3 and 1.1 nmol O₂ min^-1 mg DW^-1 for anterior and posterior gills, respectively) but was not modified in WW-exposed individuals. WW exposure also impaired crab osmoregulatory capacity; an 80 mOsm kg^-1 decrease was observed compared to FW, likely due to decreased branchial NKA activity. ROS production (DCF fluorescence in hemolymph), antioxidant defenses (superoxide dismutase and catalase activities) and oxidative damage (malondialdehyde concentration) responses varied according to animal gender. Overall, this study demonstrates that specific physiological parameters must be considered when focusing on crabs with bimodal breathing capacities. We conclude that spider crabs exposed to WW face osmoregulatory imbalances due to functional and morphological gill remodeling, which must rapidly exhaust energy reserves. These physiological disruptions could explain the ecological changes observed in the field.

Sequevar Diversity and Virulence of Ralstonia solanacearum Phylotype I on Mayotte Island (Indian Ocean)

The genetic and phenotypic diversity of the Ralstonia solanacearum species complex, which causes bacterial wilt to Solanacae, was assessed in 140 strains sampled from the main vegetable production areas of the Mayotte island. Only phylotype I strains were identified in the five surveyed areas. The strains were distributed into the following 4 sequevars: I-31 (85.7%), I-18 (5.0%), I-15 (5.7%), and I-46 (3.6%). The central area of Mayotte was the most diverse region, harboring 4 sequevars representing 47.1% of the collected strains. Virulence tests were performed under field and controlled conditions on a set of 10 tomato breeding line accessions and two commercial hybrid tomato cultivars. The strains belonging to sequevar I-31 showed the highest virulence on the tomatoes (pathotypes T-2 and T-3), whereas sequevars I-18, I-15, and I-46 were grouped into the weakly T-1 pathotype. When the tomato accessions were challenged in the field and growth chambers, the highest level of resistance were observed from the genetically related accessions Hawaii 7996, R3034, TML46, and CLN1463. These accessions were considered moderately to highly resistant to representative strains of the most virulent and prevalent sequevar (I-31). Interestingly, the Platinum F1 cultivar, which was recently commercialized in Mayotte for bacterial wilt resistance, was highly or moderately resistant to all strains. This study represents the first step in the rationalization of resistance deployment strategies against bacterial wilt-causing strains in Mayotte.

Genetic structure and gene flow of the flea Xenopsylla cheopis in Madagascar and Mayotte

Background

The flea Xenopsylla cheopis (Siphonaptera: Pulicidae) is a vector of plague. Despite this insect’s medical importance, especially in Madagascar where plague is endemic, little is known about the organization of its natural populations. We undertook population genetic analyses (i) to determine the spatial genetic structure of X. cheopis in Madagascar and (ii) to determine the potential risk of plague introduction in the neighboring island of Mayotte.

Results

We genotyped 205 fleas from 12 sites using nine microsatellite markers. Madagascan populations of X. cheopis differed, with the mean number of alleles per locus per population ranging from 1.78 to 4.44 and with moderate to high levels of genetic differentiation between populations. Three distinct genetic clusters were identified, with different geographical distributions but with some apparent gene flow between both islands and within Malagasy regions. The approximate Bayesian computation (ABC) used to test the predominant direction of flea dispersal implied a recent population introduction from Mayotte to Madagascar, which was estimated to have occurred between 1993 and 2012. The impact of this flea introduction in terms of plague transmission in Madagascar is unclear, but the low level of flea exchange between the two islands seems to keep Mayotte free of plague for now.

Conclusion

This study highlights the occurrence of genetic structure among populations of the flea vector of plague, X. cheopis, in Madagascar and suggests that a flea population from Mayotte has been introduced to Madagascar recently. As plague has not been reported in Mayotte, this introduction is unlikely to present a major concern for plague transmission. Nonetheless, evidence of connectivity among flea populations in the two islands indicates a possibility for dispersal by fleas in the opposite direction and thus a risk of plague introduction to Mayotte.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2290-6) contains supplementary material, which is available to authorized users.

Species delimitation in the reef coral genera Echinophyllia and Oxypora (Scleractinia, Lobophylliidae) with a description of two new species

Scleractinian corals are affected by environment-induced phenotypic plasticity and intraspecific morphological variation caused by genotype. In an effort to identify new strategies for resolving this taxonomic issue, we applied a molecular approach for species evaluation to two closely related genera, Echinophyllia and Oxypora, for which few molecular data are available. A robust multi-locus phylogeny using DNA sequence data across four loci of both mitochondrial (COI, ATP6-NAD4) and nuclear (histone H3, ITS region) origin from 109 coral colonies was coupled with three independent putative species delimitation methods based on barcoding threshold (ABGD) and coalescence theory (PTP, GMYC). Observed overall congruence across multiple genetic analyses distinguished two traditional species (E. echinoporoides and O. convoluta), a species complex composed of E. aspera, E. orpheensis, E. tarae, and O. glabra, whereas O. lacera and E. echinata were indistinguishable with the sequenced loci. The combination of molecular species delimitation approaches and skeletal character observations allowed the description of two new reef coral species, E. bulbosa sp. n. from the Red Sea and E. gallii sp. n. from the Maldives and Mayotte. This work demonstrated the efficiency of multi-locus phylogenetic analyses and recently developed molecular species delimitation approaches as valuable tools to disentangle taxonomic issues caused by morphological ambiguities and to re-assess the diversity of scleractinian corals.

Trophic relationships between metazooplankton communities and their plankton food sources in the Iles Eparses (Western Indian Ocean)

Coral reef and atoll lagoons are among the most diversified marine ecosystems but also the most affected by the combined effects of climate change and human activities. The Iles Eparses (Scattered Islands) in the Western Indian Ocean have been little affected by human pressure and can be considered to be "pristine" ecosystems. Metazooplankton plays a major role in the functioning and productivity of aquatic ecosystems, and this study was undertaken: (i) to determine the spatial abundance, distribution and species composition of metazooplankton, (ii) to assess the effect of metazooplankton grazing on pico- and nanophytoplankton and (iii) to analyze the trophic positions of metazooplankton by using the stable isotope signatures of a wide variety of taxa and particulate organic matter from the Iles Eparses and Mayotte. Tromelin Island (which is not located in the Mozambique Channel) had the lowest metazooplankton abundance with no cyanobacteria Trichodesmium spp. or mollusks (pteropods) presence, and with δ(15)N signatures of organisms that were higher than for the islands in the Mozambique Channel. Trichodesmium spp. was found in the Mozambique Channel and the plankton food web was probably based preferentially on these cyanobacteria with lower δ(15)N signatures indicating direct or indirect trophic transfer of diazotrophic nitrogen to metazooplankton. Three of the islands were distinct: Europa had the highest proportion of copepods, with oithonids being dominant, which is typical of rich mangrove systems, while Juan de Nova and Mayotte seemed to be the sites most affected by human activity with a high abundance of appendicularians and distinct particulate organic matter ∂(13)C signatures. Grazing experiments showed that food could be a limiting factor for metazooplankton in the Iles Eparses. However, the effect of metazooplankton grazing on phytoplankton appeared to be very low (0.01-2.32% of the total phytoplankton per day).

[Malaria in the Comoros Archipelago in 2015: status after 15 years of fight]

The four volcanic islands of the Comoros archipelago are an area of intense, stable and permanent malaria transmission, almost exclusively with Plasmodium falciparum. Our purpose is to describe the current situation on malaria in Mayotte and Comoros in 2015, after the implementation of various strategies of control during the past 15 years. In 2015, Mayotte is in the phase of elimination of malaria. In the three islands forming the Union of Comoros, the transmission is much lower in the islands of Anjouan (incidence of 0.02‰) and Moheli (incidence of 0.14‰), ranking the two islands in pre-elimination phase. Grande Comore (incidence of 3.68‰) remains in the control phase with not enough time to assess what the mass treatment campaign long-term effects might be. These strategies could be applied in other islands with endemic malaria and with limited population.

A nonet of novel species of Monanthotaxis (Annonaceae) from around Africa

As part of an ongoing revision of the genus Monanthotaxis Baill. (Annonaceae), nine new species are described and one variety is reinstated to species rank. Two new species from West Africa (Monanthotaxis aquila P.H.Hoekstra, sp. nov. and Monanthotaxis atewensis P.H.Hoekstra, sp. nov.), four new species from Central Africa (Monanthotaxis couvreurii P.H.Hoekstra, sp. nov., Monanthotaxis latistamina P.H.Hoekstra, sp. nov., Monanthotaxis tripetala P.H.Hoekstra, sp. nov. and Monanthotaxis zenkeri P.H.Hoekstra, sp. nov.), one new species from Tanzania (Monanthotaxis filipes P.H.Hoekstra, sp. nov.), one new species from the area around Maputo (Monanthotaxis maputensis P.H.Hoekstra, sp. nov.), one new species from the Comoro Islands (Monanthotaxis komorensis P.H.Hoekstra, sp. nov.) and Monanthotaxis klainei (Engl.) Verdc. var. angustifolia (Boutique) Verdc. is raised to species level leading to the replacement name Monanthotaxis atopostema P.H.Hoekstra, nom. nov. (not Monanthotaxis angustifolia (Exell) Verdc.). Complete descriptions, comparisons with related species, ecological information and IUCN conservation assessments are given for the new species. Five species were classified as critical endangered, two species as endangered, one as vulnerable and one as least concern, warranting the need of further collecting and studying those species.

[Characteristics and health care pathways of HIV-infected patients in Mayotte (1990-2010)]

OBJECTIVES

To evaluate the characteristics of HIV-infected patients treated in Mayotte, focusing on health care pathways.

METHODS

Observational study, with retrospective collection of data from medical charts according to a standardized questionnaire. All HIV-infected patients who consulted at the Centre Hospitalier de Mayotte from 1990 through 2010 were included. Patients were classified as lost to follow-up if they had not consulted for at least 6 months and if no information about their outcome was available. Variables associated with loss to follow-up were analyzed by bivariate analysis (Chi(2)), and then multivariate analysis (logistic regression).

RESULTS

Overall, 236 patients were enrolled (134 females, 102 males), with a mean age of 30.7 ± 12 years, and a median CD4 cell count of 390/mm(3) at diagnosis. HIV testing was most often ordered because of: i) HIV-related symptoms (n = 70); ii) risk factors (n = 67); iii) pregnancy (n = 51). The 52 patients (22%) lost to follow-up were less likely to have medical insurance (52% versus 67%, p = 0.05) or antiretroviral treatment (56% versus 71%, p = 0.04), and were more frequently aged younger than 15 years (15% versus 2%, p<0.001). On multivariate analysis, initial management at the Centre Hospitalier de Mayotte (OR 2.62 [1.09-6.29], p = 0.03, and the absence of antiretroviral treatment (OR 1.97 [1.00-3.89], p = 0.05) were significantly associated with loss to follow-up.

CONCLUSION

The HIV epidemic in Mayotte follows an African pattern in terms of main transmission pathways, age and circumstances of diagnosis, but the median CD4 cell count at diagnosis is closer to the pattern in metropolitan France. The rate of patients lost to follow-up is high (22%), mostly linked to problems with access to care.

A revision of the ant genus Mystrium in the Malagasy region with description of six new species and remarks on Amblyopone and Stigmatomma (Hymenoptera, Formicidae, Amblyoponinae)

The genus Mystrium is revised for the Malagasy region. Six species, Mystrium barrybresslerisp. n., Mystrium labyrinthsp. n., Mystrium equessp. n., Mystrium mirrorsp. n., Mystrium shadowsp. n., and Mystrium janovitzisp. n. are described as new. Two existing names, Mystrium fallax Forel and Mystrium stadelmanni Forel, are synonymized with Mystrium voeltzkowi Forel and Mystrium mysticum Roger, respectively. All recognized species, including species outside of the Malagasy region, are assigned to one of the three newly proposed species groups. The associations between existing names and males are reexamined, and males of eight of the ten Malagasy species are described or redescribed. The taxonomic history of Mystrium highlights the importance of using unique identifiers when designating type specimens and the use of deposited vouchers in phylogenetic and ecological studies. Keys to species for workers, queens, and males are provided. Furthermore, a neotype for Mystrium mysticum is designated, as well as lectotypes for Mystrium camillae Emery, Mystrium rogeri Forel, Mystrium fallax Forel, Mystrium oberthueri Forel, Mystrium stadelmanni Forel, and Mystrium voeltzkowi Forel. Stigmatomma gingivale (Brown) is reassigned to Amblyopone as comb. rev. and Amblyopone awa Xu & Chu, Amblyopone kangba Xu & Chu, Amblyopone meiliana Xu & Chu, and Amblyopone zomae Xu & Chu are transferred to the genus Stigmatomma as comb. n.