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Fusarium wilt of banana, caused by the soil-borne pathogen Fusarium oxysporum f. sp. cubense (Foc), is a major constraint to banana production worldwide (Viljoen et al., 2020). Currently, Cavendish bananas are severely affected by Foc Tropical Race 4 (TR4) globally. In Africa, Foc TR4 was first detected in northern Mozambique in 2013 (Viljoen et al., 2020), and has since been found on the island of Mayotte in the Mozambique Channel off the coast of southeastern Africa (Aguayo et al., 2021). In early 2023, severe leaf-yellowing and wilting of Cavendish banana plants was observed on Cavendish banana plants at several small holder farmer properties in Grande Comoros (Ngazidja) including in Ntsinimoipanga (-11,790054 S, 43°25'47,04384 E), Batou (-11,499716 S, 43°21'51,71976''E), Madjeweni (-11,8217 S , 43°16'41''E) and Mdé (-11°41'54'' S, 43°15'20''E). When the pseudostems of these plants were split open, a reddish-brown internal discoloration of the vascular tissue became apparent. Discolored strands of diseased plants were collected, and the causal agent identified using DNA-based techniques, vegetative compatibility group (VCG) analysis and pathogenicity testing. The samples were plated onto potato dextrose agar and single-spored and isolated from individual diseased plants identified as F. oxysporum based on cultural and morphological characteristics. These include the production of white fungal colonies with a purple center, infrequent production of macroconidia, but an abundance of microconidia on short monophialides, and terminal or intercalary chlamydospores (Leslie and Summerell, 2006). Foc TR4 was identified from seven isolates by conventional (Dita et al., 2010) and quantitative-PCR (Matthews et al., 2020), and with loop-mediated isothermal amplification (LAMP) (Ordóñez et al., 2021). All seven isolates were confirmed as members of the VCG 01213/16 complex when nit-1 mutants of the unknown Foc isolates were compatible with Nit-M mutants of the Foc VCG 01213 and VCG 01216 tester strains. Two isolates were then selected for pathogenicity testing, and 2-month-old tissue culture-derived Cavendish plants (cv. Williams) inoculated by using the method described by Ndayihanzamaso et al. (2022). After 4 weeks, the Foc TR4-inoculated plants produced wilting symptoms and internal rhizome discoloration typical of Fusarium wilt. Foc TR4 was reisolated from the inoculated plants and identified by qPCR (Matthews et al. 2020), thereby fulfilling Koch's postulates. These results provide scientific proof of the presence of Foc TR4 in a second island in the Comoros archipelago. Comprehensive surveys will be conducted in all three of the Comoros Islands to assess the presence and impact of Foc TR4 to implement containment strategies. Collaborative initiatives and coordinated actions among growers and other stakeholders are needed to prevent the spread of Foc TR4 to more Southwest Indian Ocean islands and countries on the East African coasts. The importance of banana for food security and livelihoods, and the unique genetic diversity of bananas found on the Comoros islands, requires the eradication and isolation of diseased bananas on the short term, and the screening of local banana varieties for Foc TR4 resistance on the longer term.
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This study aimed to analyse, for the first time, five MHC class II polymorphic Alu insertions in a population with a strong Sub-Saharan African genetic background: the Ngazidja islanders and compare its allelic and haplotypic data with Worldwide populations. The genotyping was performed in 80 individuals, using simple PCR and agarose gel electrophoresis methods. Allele and haplotype frequencies, genetic diversity, Hardy-Weinberg equilibrium deviations, normalized deviate of homozygotes and pairwise linkage disequilibrium were estimated. The phylogenetic analyses included the available population data. In Ngazidja, the MHC class II Alu insertion frequencies ranged from 0.119 for AluORF10 to 0.588 for AluDPB2. Concerning haplotypes, the most predominant were the ones with only the AluDPB2 insertion allele (AluDPB2*2-AluDQA2*1-AluDQA1*1-AluDRB1*1-AluORF10*1), followed by the theoretical ancestral haplotype with no Alu insertions (AluDPB2*1-AluDQA2*1-AluDQA1*1-AluDRB1*1-AluORF10*1) and finally the haplotype with the AluDPB2 and AluDQA1 Alu insertions (AluDPB2*2-AluDQA2*1-AluDQA1*2-AluDRB1*1-AluORF10*1) with frequencies of 19.2%, 15% and 12.9%, respectively. In the phylogenetic analyses, our results indicate that the Ngazidja people are genetically differentiated from the other populations of the analysis; we found also a new haplotype that can be probably characteristic of Sub-Saharans and finally confirm the usefulness of these markers as genetic and evolutionary tools for studying genetic variations among populations of different origins.
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Elementos Alu , Polimorfismo Genético , Alelos , Elementos Alu/genética , Pueblo Asiatico , Biología , Comoras , Frecuencia de los Genes/genética , Haplotipos/genética , Humanos , FilogeniaRESUMEN
At the dawn of the second millennium, the expansion of the Indian Ocean trading network aligned with the emergence of an outward-oriented community along the East African coast to create a cosmopolitan cultural and trading zone known as the Swahili Corridor. On the basis of analyses of new genome-wide genotyping data and uniparental data in 276 individuals from coastal Kenya and the Comoros islands, along with large-scale genetic datasets from the Indian Ocean rim, we reconstruct historical population dynamics to show that the Swahili Corridor is largely an eastern Bantu genetic continuum. Limited gene flows from the Middle East can be seen in Swahili and Comorian populations at dates corresponding to historically documented contacts. However, the main admixture event in southern insular populations, particularly Comorian and Malagasy groups, occurred with individuals from Island Southeast Asia as early as the 8th century, reflecting an earlier dispersal from this region. Remarkably, our results support recent archaeological and linguistic evidence-based suggestions that the Comoros archipelago was the earliest location of contact between Austronesian and African populations in the Swahili Corridor.
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Flujo Génico , Genética de Población , Asia , Australia , Comoras , Variación Genética , Humanos , Kenia , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
BACKGROUND: Despite several control interventions resulting in a considerable decrease in malaria prevalence in the Union of the Comoros, the disease remains a public health problem with high transmission in Grande Comore compared to neighbouring islands. In this country, only a few studies investigating the genetic diversity of Plasmodium falciparum have been performed so far. For this reason, this study aims to examine the genetic diversity of P. falciparum by studying samples collected in Grande Comore in 2012 and 2013, using merozoite surface protein 1 (msp1), merozoite surface protein 2 (msp2) and single nucleotide polymorphism (SNP) genetic markers. METHODS: A total of 162 positive rapid diagnostic test (RDT) samples from Grande Comore were used to extract parasite DNA. Allelic families K1, Mad20 and RO33 of the msp1 gene as well as allelic families IC3D7 and FC37 of the msp2 gene were determined by using nested PCR. Additionally, 50 out of 151 samples were genotyped to study 24 SNPs by using high resolution melting (HRM). RESULTS: Two allelic families were predominant, the K1 family of msp1 gene (55%) and the FC27 family of msp2 gene (47.4%). Among 50 samples genotyped for 24 SNPs, 42 (84%) yielded interpretable results. Out of these isolates, 36 (85%) were genetically unique and 6 (15%) grouped into two clusters. The genetic diversity of P. falciparum calculated from msp1 and msp2 genes and SNPs was 0.82 and 0.61, respectively. CONCLUSION: In summary, a large genetic diversity of P. falciparum was observed in Grande Comore. This may favour persistence of malaria and might be one of the reasons for the high malaria transmission compared to neighbouring islands. Further surveillance of P. falciparum isolates, mainly through environmental management and vector control, is warranted until complete elimination is attained.
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Antígenos de Protozoos/genética , Variación Genética , Proteína 1 de Superficie de Merozoito/genética , Plasmodium falciparum/genética , Polimorfismo de Nucleótido Simple , Proteínas Protozoarias/genética , Comoras , Reacción en Cadena de la PolimerasaRESUMEN
BACKGROUND: Since the novel coronavirus emerged in late 2019, the scientific and public health community around the world have sought to better understand, surveil, treat, and prevent the disease, COVID-19. In sub-Saharan Africa (SSA), many countries responded aggressively and decisively with lockdown measures and border closures. Such actions may have helped prevent large outbreaks throughout much of the region, though there is substantial variation in caseloads and mortality between nations. Additionally, the health system infrastructure remains a concern throughout much of SSA, and the lockdown measures threaten to increase poverty and food insecurity for the subcontinent's poorest residents. The lack of sufficient testing, asymptomatic infections, and poor reporting practices in many countries limit our understanding of the virus's impact, creating a need for better and more accurate surveillance metrics that account for underreporting and data contamination. OBJECTIVE: The goal of this study is to improve infectious disease surveillance by complementing standardized metrics with new and decomposable surveillance metrics of COVID-19 that overcome data limitations and contamination inherent in public health surveillance systems. In addition to prevalence of observed daily and cumulative testing, testing positivity rates, morbidity, and mortality, we derived COVID-19 transmission in terms of speed, acceleration or deceleration, change in acceleration or deceleration (jerk), and 7-day transmission rate persistence, which explains where and how rapidly COVID-19 is transmitting and quantifies shifts in the rate of acceleration or deceleration to inform policies to mitigate and prevent COVID-19 and food insecurity in SSA. METHODS: We extracted 60 days of COVID-19 data from public health registries and employed an empirical difference equation to measure daily case numbers in 47 sub-Saharan countries as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R. RESULTS: Kenya, Ghana, Nigeria, Ethiopia, and South Africa have the most observed cases of COVID-19, and the Seychelles, Eritrea, Mauritius, Comoros, and Burundi have the fewest. In contrast, the speed, acceleration, jerk, and 7-day persistence indicate rates of COVID-19 transmissions differ from observed cases. In September 2020, Cape Verde, Namibia, Eswatini, and South Africa had the highest speed of COVID-19 transmissions at 13.1, 7.1, 3.6, and 3 infections per 100,0000, respectively; Zimbabwe had an acceleration rate of transmission, while Zambia had the largest rate of deceleration this week compared to last week, referred to as a jerk. Finally, the 7-day persistence rate indicates the number of cases on September 15, 2020, which are a function of new infections from September 8, 2020, decreased in South Africa from 216.7 to 173.2 and Ethiopia from 136.7 to 106.3 per 100,000. The statistical approach was validated based on the regression results; they determined recent changes in the pattern of infection, and during the weeks of September 1-8 and September 9-15, there were substantial country differences in the evolution of the SSA pandemic. This change represents a decrease in the transmission model R value for that week and is consistent with a de-escalation in the pandemic for the sub-Saharan African continent in general. CONCLUSIONS: Standard surveillance metrics such as daily observed new COVID-19 cases or deaths are necessary but insufficient to mitigate and prevent COVID-19 transmission. Public health leaders also need to know where COVID-19 transmission rates are accelerating or decelerating, whether those rates increase or decrease over short time frames because the pandemic can quickly escalate, and how many cases today are a function of new infections 7 days ago. Even though SSA is home to some of the poorest countries in the world, development and population size are not necessarily predictive of COVID-19 transmission, meaning higher income countries like the United States can learn from African countries on how best to implement mitigation and prevention efforts. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/21955.
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Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Política de Salud , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Vigilancia en Salud Pública , África del Sur del Sahara/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/virología , Femenino , Humanos , Masculino , Modelos Biológicos , Pandemias , Neumonía Viral/virología , Sistema de Registros , SARS-CoV-2RESUMEN
Background: Alu elements are attractive markers for population genetics, disease, forensics and paternity analyses, due to their particular characteristics. Five polymorphic Alu insertions within the MHC class I region have been little examined in human populations. Aim: The analysis of the genetic diversity of autochthonous Comorians from the three major islands of the archipelago by these polymorphic MHC Alus and to assess their relationships together and with other populations. Subjects and methods: Two hundred and fifty-seven unrelated participants from the Comoros archipelago, Grande Comore (86), Anjouan (93) and Moheli (78), were examined for five MHC Alu insertions. The data were analysed for intra- and inter-population genetic variation. Results: All MHC Alu were polymorphic in the three samples and only one significant differentiation was observed between Anjouan and Moheli. According to the MDS and AMOVA results, the populations included in the inter-population analyses were grouped in three major clusters according to their genetic ancestry. The haplotype diversity showed by the Comorians is higher than in previously studied African populations and occupies an intermediate position between African and Asian clusters. Conclusion: MHC Alu insertions are useful markers to study micro-geographical genetic variations. Using these polymorphisms, new insights have been obtained about the biological history and evolution of the Comoros.
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Elementos Alu/genética , Genes MHC Clase I/genética , Comoras , Variación Genética , Haplotipos , Humanos , Polimorfismo GenéticoRESUMEN
East Coast fever (ECF), one of the most serious tick-borne diseases in sub-Saharan and eastern Africa, was introduced to the island of Grande Comore in 2002 through zebu import from Tanzania, resulting in at least a 10% loss of livestock. A participatory epidemiology initiative was launched in 2015 to gain a better understanding of ECF epidemiology. Thirty-six villages were investigated involving 36 focus group sessions and 120 individual questionnaires. Farmers' knowledge of ECF and of priority diseases affecting the country was assessed, and the impacts of ECF and other major diseases were compared by a scoring method. The results showed that 69.4% (95% CI [51.3, 87.5%]) of the farmers had good to very good knowledge of ECF. The most important cattle diseases on Grande Comore were considered to be East Coast fever, heartwater, babesiosis, and cutaneous diseases. About 58% of the farmers (95% CI [49.2, 66.8%]) use curative treatments when cattle were sick. Between January and September 2015, the ECF incidence was estimated at 18.5% (95% CI [15.5, 21.4%]), and 87.5% (95% CI [72.7, 100%]) of the cattle infected by ECF died. The ECF incidence estimated in our study was found to be less when compared to that observed in Tanzania even though the climatic conditions in the Union of the Comoros are suitable for the biological vector of ECF, the tick species Rhipicephalus appendiculatus. Access to chemical treatment and its effectiveness against ECF, as well as controlling borders and organizing quarantine, are discussed.
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Participación de la Comunidad , Theileriosis/epidemiología , Enfermedades por Picaduras de Garrapatas/epidemiología , Animales , Vectores Arácnidos , Bovinos , Comoras/epidemiología , Humanos , Incidencia , Rhipicephalus , Tanzanía/epidemiología , Theileriosis/prevención & control , Enfermedades por Picaduras de Garrapatas/prevención & controlRESUMEN
INTRODUCTION: The government plan for the fight against drugs and addictive behaviors 2013-2017 includes several actions concerning French overseas territories, in particular to strengthen information on drug addiction. The Interministerial mission for combating drugs and addictive behaviors (MILD&CA) has commissioned the Bordeaux addictovigilance center to strengthen exchanges on addictovigilance with Réunion Island and Mayotte and to make an inventory of problematic drug use in these two French departments of Indian Ocean. METHOD: Two pharmacologists went on an assignment 4.5 days in Reunion and 2 days in Mayotte and met more than fifty people involved in addictology. RESULTS: In Reunion Island, alcohol is the psychoactive substance by far the most used, followed by zamal, the local name for cannabis. There is a strong tradition of medicines diversion, including trihexyphenidyl, barbiturates and more recently, benzodiazepines. Heroin and cocaine are rarely available. Poly drug use is common. In Mayotte, bangué, the local name for cannabis, is the most used psychoactive substance. The use of "chimique" has emerged in 2012-2013. It is used mainly by teenagers and young adults, causing numerous cases of hospitalizations and consultations in addictology in 2015. These could be synthetic cannabinoids bought on the Internet. DISCUSSION: It is important to report new or serious cases to better take into account the particularities of these two departments in the French addictovigilance data and to enable analysis of substances consumed.
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Psicotrópicos , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Adulto , Anciano , Alcoholismo/epidemiología , Cannabinoides , Femenino , Humanos , Islas del Oceano Índico/epidemiología , Masculino , Abuso de Marihuana/epidemiología , Persona de Mediana Edad , Desvío de Medicamentos bajo Prescripción , Factores Socioeconómicos , Trastornos Relacionados con Sustancias/prevención & control , Adulto JovenRESUMEN
PREMISE OF THE STUDY: The Western Indian Ocean Region (WIOR) is a biodiversity hotspot providing an ideal setting for exploring the origins of insular biodiversity and dynamics of island colonization. We aimed to investigate the origins of the WIOR Psychotrieae alliance (Rubiaceae) with typically small, probably mainly bird-dispersed drupes, and the timing and direction or sequence of its colonization events in the region. METHODS: We used the program BEAST to estimate divergence times and Lagrange for biogeographic reconstruction. KEY RESULTS: The alliance has reached the WIOR at least 14 times via dispersals from Africa along with Asia and the Pacific mostly during the last 10 My, with at least one back-colonization to Africa. We inferred the earliest dispersal to Madagascar from the Pacific or Asia in the Miocene and numerous out-of-Madagascar dispersals to the nearby archipelagos but no dispersal out of those archipelagos. Gynochthodes with multiple fruits reached Madagascar twice from the Pacific possibly via ocean drifting. Psychotria with dry fruits (schizocarps) colonized Madagascar from the Pacific or Asia before reaching the Comoros from Madagascar possibly via wind dispersal. CONCLUSIONS: This study reinforces the pivotal role of dispersal in shaping the WIOR biodiversity and as the critical initiating step in the generation of endemic biodiversity on its islands. The WIOR alliance shows strong Asian and Pacific affinities despite the proximity of the region to Africa. Madagascar has served as a stepping-stone for subsequent dispersal to the rest of the region. The Afro-Malagasy-Seychelles genus Craterispermum and the Malagasy Puffia may represent relictual lineages.
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Filogenia , Rubiaceae/genética , Islas del Oceano Índico , FilogeografíaRESUMEN
BACKGROUND: In Comoros, the widespread of chloroquine (CQ)-resistant Plasmodium falciparum populations was a major obstacle to malaria control, which led to the official withdrawal of CQ in 2004. Continuous monitoring of CQ-resistant markers of the P. falciparum CQ resistant transporter (pfcrt) and the P. falciparum multiple drug resistance 1 (pfmdr-1) is necessary inder to obtain first-hand information on CQ susceptibility of parasite populations in the field. The objective of this study is to assess the prevalence and evolution of CQ-resistance in the P. falciparum populations on the Comoros' Grande Comore island after withdrawal of CQ. METHODS: A total of 207 P. falciparum clinical isolates were collected from the island, including 118 samples from 2006 to 2007 and 89 samples from 2013 to 2014. Nucleotide substitutions in the pfcrt and pfmdr-1 genes linked to CQ response in parasite isolates were assessed using nested PCR and DNA sequencing. RESULTS: From the pfcrt gene segment sequenced, we detected C72S, M74I, N75E, and K76T substitutions in the parasite isolates collected from both 2006-2007 to 2013-2014 periods. Significant decline of pfcrt resistant alleles at C72S (42.6 to 6.9 %), M74I (39.1 to 14.9 %), N75E (63.5 to 18.3 %), and K76T (72.2 to 19.5 %) from 2006-2007 to 2013-2014 were observed, and the frequency of pfcrt wild type allele was significantly increased from 19.1 % in 2006-2007 to 75.8 % in 2013-2014. Sequence analysis of pfmdr-1 also detected point mutations at codons N86Y, Y184F, and D1246Y, but not S1034C and N1042D, in the isolates collected from both examined periods. An increasing trend in the prevalence of the pfmdr-1 wild type allele (NYD, 4.3 % in 2006-2007; and 28.7 % in 2013-2014), and a decreasing trend for pfmdr-1 N86Y mutation (87.0 % in 2006-2007; and 40.2 % in 2013-2014) were observed in our samples. CONCLUSIONS: The present data indicate that the prevalence and patterns of mutant pfcrt and pfmdr-1 dramatically decreased in the Grande Comore isolates from 2006 to 2014, suggesting that the CQ-sensitive P. falciparum strains have returned after the withdrawal of CQ. The data also suggests that the parasites with wild type pfcrt/pfdmr-1 genes may have growth and/or transmission advantages over the mutant parasites. The information obtained from this study will be useful for developing and updating anti-malarial treatment policy in Grande Comore island.
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Antimaláricos/farmacología , Cloroquina/farmacología , Utilización de Medicamentos , Malaria Falciparum/epidemiología , Proteínas de Transporte de Membrana/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/aislamiento & purificación , Proteínas Protozoarias/genética , Adulto , Sustitución de Aminoácidos , Niño , Preescolar , Comoras/epidemiología , Femenino , Humanos , Malaria Falciparum/parasitología , Masculino , Mutación Missense , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADNRESUMEN
Chikungunya virus (CHIKV) from a human sample collected during the 2005 Chikungunya outbreak in the Comoros Island, showed distinct and reproducible large (L2) and small (S7) plaques which were characterized in this study. The parent strain and plaque variants were analysed by in vitro growth kinetics in different cell lines and their genetic similarity assessed by whole genome sequencing, comparative sequence alignment and phylogenetic analysis. In vitro growth kinetic assays showed similar growth patterns of both plaque variants in Vero cells but higher viral titres of S7 compared to L2 in C6/36 cells. Amino acids (AA) alignments of the CHIKV plaque variants and S27 African prototype strain, showed 30 AA changes in the non-structural proteins (nsP) and 22 AA changes in the structural proteins. Between L2 and S7, only two AAs differences were observed. A missense substitution (C642Y) of L2 in the nsP2, involving a conservative AA substitution and a nonsense substitution (R524X) of S7 in the nsP3, which has been shown to enhance O'nyong-nyong virus infectivity and dissemination in Anopheles mosquitoes. The phenotypic difference observed in plaque size could be attributed to one of these AA substitutions. Phylogenetic analysis showed that the parent strain and its variants clustered closely together with each other and with Indian Ocean CHIKV strains indicating circulation of isolates with close evolutionary relatedness in the same outbreak. These observations pave way for important functional studies to understand the significance of the identified genetic changes in virulence and viral transmission in mosquito and mammalian hosts.
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Fiebre Chikungunya/virología , Virus Chikungunya/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Anopheles/virología , Secuencia de Bases , Línea Celular , Fiebre Chikungunya/transmisión , Virus Chikungunya/crecimiento & desarrollo , Chlorocebus aethiops , Comoras , Brotes de Enfermedades , Flujo Genético , Variación Genética , Humanos , Datos de Secuencia Molecular , Familia de Multigenes , Filogenia , Alineación de Secuencia , Células Vero , Proteínas no Estructurales ViralesRESUMEN
[This corrects the article DOI: 10.3389/fmicb.2024.1343917.].
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Introduction: The influence of Wolbachia on mosquito reproduction and vector competence has led to renewed interest in studying the genetic diversity of these bacteria and the phenotypes they induced in mosquito vectors. In this study, we focused on two species of Eretmapodites, namely Eretmapodites quinquevittatus and Eretmapodites subsimplicipes, from three islands in the Comoros archipelago (in the Southwestern Indian Ocean). Methods: Using the COI gene, we examined the mitochondrial genetic diversity of 879 Eretmapodites individuals from 54 sites. Additionally, we investigated the presence and genetic diversity of Wolbachia using the wsp marker and the diversity of five housekeeping genes commonly used for genotyping through Multiple Locus Sequence Typing (MLST). Results and discussion: Overall, Er. quinquevittatus was the most abundant species in the three surveyed islands and both mosquito species occurred in sympatry in most of the investigated sites. We detected a higher mitochondrial genetic diversity in Er. quinquevittatus with 35 reported haplotypes (N = 615 specimens, Hd = 0.481 and π = 0.002) while 13 haplotypes were found in Er. subsimplicipes (N = 205 specimens, Hd = 0.338 and π = 0.001), this difference is likely due to the bias in sampling size between the two species. We report for the first time the presence of Wolbachia in these two Eretmapodites species. The prevalence of Wolbachia infection varied significantly between species, with a low prevalence recorded in Er. quinquevittatus (0.8%, N = 5/627) while infection was close to fixation in Er. subsimplicipes (87.7%, N = 221/252). Both male and female individuals of the two mosquito species appeared to be infected. The analysis of MLST genes revealed the presence of two Wolbachia strains corresponding to two new strain types (STs) within the supergroups A and B, which have been named wEretA and wEretB. These strains were found as mono-infections and are closely related, phylogenetically, to Wolbachia strains previously reported in Drosophila species. Finally, we demonstrate that maternal transmission of Wolbachia is imperfect in Er. subsimplicipes, which could explain the presence of a minority of uninfected individuals in the field.
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Data collected by the GeoSentinel Surveillance Network for 1,415 ill travelers returning from Indian Ocean islands during 1997-2010 were analyzed. Malaria (from Comoros and Madagascar), acute nonparasitic diarrhea, and parasitoses were the most frequently diagnosed infectious diseases. An increase in arboviral diseases reflected the 2005 outbreak of chikungunya fever.
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Infecciones por Alphavirus/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Dengue/epidemiología , Malaria Falciparum/epidemiología , Esquistosomiasis/epidemiología , Adolescente , Adulto , Anciano , Fiebre Chikungunya , Enfermedades Transmisibles Emergentes/transmisión , Comoras/epidemiología , Femenino , Enfermedades Transmitidas por los Alimentos/epidemiología , Humanos , Incidencia , Madagascar/epidemiología , Malaria Falciparum/transmisión , Masculino , Persona de Mediana Edad , Vigilancia de Guardia , Viaje , Adulto JovenRESUMEN
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.
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Malaria , Humanos , África , Comoras/epidemiología , Malaria/epidemiologíaRESUMEN
SETTING: The Union of the Comoros has experienced a persistent notification gap in TB cases despite several strategic changes, including molecular diagnosis and contact investigation. We therefore performed a TB patient pathway analysis (PPA) under the National Tuberculosis Programme (NTP). OBJECTIVE: To assess the alignment of healthcare-seeking behaviour and TB service availability to clarify the reasons for these missing cases. DESIGN: Three primary data sources, including a national list of health facilities, TB surveillance data and care-seeking behaviour data, were analysed at the national and regional levels to determine access to TB diagnosis and the initial point of care-seeking. Summary data were visualised using the standardised PPA Wizard programme, and the analysis was completed using demographic and socio-economic data. RESULTS: At the initial point of care-seeking, 18% of patients had access to TB services, available only in nine centralised public health facilities. Furthermore, 30% of patients initially consulted in the informal sector and 45% in the formal public or private sector in health facilities, both of which lacked the capacity for TB diagnosis or first-line treatment. CONCLUSION: The concentration of and limited access to TB services at the intermediate and central levels of care indicate a need for decentralisation efforts.
CONTEXTE: L'Union des Comores a enregistré un déficit persistant de notifications de cas de TB malgré plusieurs changements stratégiques, comme la mise en place du diagnostic moléculaire et de la recherche des contacts. Nous avons donc réalisé une analyse du parcours des patients atteints de TB dans le cadre du Programme national de lutte contre la TB (NTP). OBJECTIF: Évaluer la concordance entre le comportement en matière de recherche de soins et la disponibilité des services de lutte contre la TB afin de clarifier les raisons de ces cas manquants. MÉTHODES: Trois sources de données primaires, dont une liste nationale des établissements de santé, des données de surveillance de la TB et des données sur les comportements en matière de recherche de soins, ont été analysées aux niveaux national et régional pour déterminer l'accès au diagnostic de la TB et le point initial de la recherche de soins. Les données récapitulatives ont été visualisées à l'aide du programme Wizard d'analyse standardisée du parcours du patient, et l'analyse a été complétée à l'aide de données démographiques et socio-économiques. RÉSULTATS: Au point de départ de la recherche de soins, 18% des patients avaient accès aux services de lutte contre la TB, disponibles uniquement dans neuf établissements de santé publics centralisés. Par ailleurs, 30% des patients ont initialement consulté dans le secteur informel et 45% dans le secteur formel (établissements de santé publics ou privés), qui manquent tous deux des capacités nécessaires au diagnostic de la TB ou au traitement de première ligne. CONCLUSION: La concentration et l'accès limité aux services de lutte contre la TB aux niveaux intermédiaire et central de soins sont révélateurs des efforts à entreprendre en matière de décentralisation.
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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.
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Neoplasias , Humanos , Niño , Reunión/epidemiología , Estudios Retrospectivos , Comoras , FranciaRESUMEN
Knowledge, attitudes, and practices (KAP) surveys on malaria and antimalarial mass drug administration (MDA) have not received much attention in the Union of the Comoros. This study is a household-based cross-sectional survey using a multi-stage sampling technique aiming at investigating KAP toward malaria and antimalarial MDA with artemisinin-piperaquine among heads of households on Grande Comore Island, the largest island of the Comoros. A predefined structured questionnaire containing socio-demographic characteristics and questions about malaria and antimalarial MDA was administered to 1,368 randomly selected heads of households from 10 malaria-endemic villages on Grande Comore Island. The results showed that 81.4% of the heads of households knew that malaria is a transmissible disease, 77.6% recognized mosquitoes as the vectors of malaria, and 70.8% recognized fever as one of the frequent symptoms of malaria; 40.8% of respondents remembered the name of the antimalarial drug used for MDA, and 62.1% remembered the color of the antimalarial tablets; and 65.1% chose to go to a public health center to seek treatment as their first option within 24 hr of the onset of initial malaria symptoms. This study found that most heads of households had a reasonable level of knowledge about malaria and antimalarial MDA. However, only 7.3% obtained full points on all knowledge-related questions. Misconceptions about malaria cause, transmission, diagnostic method, and antimalarial MDA exist in the community of Grande Comore Island. As the Comoros continues to put great efforts to go toward malaria elimination, the community's KAP on malaria and antimalarial MDA is crucial to guarantee the community's long-term adherence to malaria elimination interventions and could become key to guaranteeing malarial elimination in the Comoros. Therefore, there is a great need to improve malaria prevention awareness through strengthening malaria education and promoting behavioral change. Heads of households should be the core target of malaria education and behavioral change for malaria elimination.
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Antimaláricos , Malaria , Animales , Humanos , Antimaláricos/uso terapéutico , Conocimientos, Actitudes y Práctica en Salud , Administración Masiva de Medicamentos , Comoras/epidemiología , Estudios Transversales , Mosquitos Vectores , Malaria/tratamiento farmacológico , Malaria/epidemiología , Malaria/prevención & controlRESUMEN
BACKGROUND: Malaria significantly rebounded in 2018 in the Comoros; this created an urgent need to conduct clinical trials to investigate the effectiveness of artemisinin and its derivatives. METHODS: An open-label, non-randomised controlled trial of artemisinin-piperaquine (AP) and artemether-lumefantrine (AL) was conducted in Grande Comore island from June 2019 to January 2020. A total of 238 uncomplicated falciparum malaria cases were enrolled and divided 1:1 into two treatments. The primary endpoint was the 42-day adequate clinical and parasitological responses (ACPR). Secondary endpoints were parasitaemia and fever clearance at day 3, gametocytes and tolerability. RESULTS: The 42-day ACPR before and after PCR correction were 91.43% (95% CI 83.93-95.76%) and 98.06% (95% CI 92.48-99.66%) for AP treatment, respectively, and 96.00% (95% CI 88.17-98.14%) and 98.97% (95% CI 93.58-99.95%) for AL treatment, respectively. Complete clearance of the parasitaemia and fever for both groups was detected on day 3. Gametocytes disappeared on day 21 in the AP group and on day 2 in AL group. Specifically, the adverse reactions were mild in both groups. CONCLUSIONS: It was found that AP and AL maintained their high efficacy and tolerance in the Comoros. Nonetheless, asymptomatic malaria infections bring new challenges to malaria control.