RESUMO
La Réunion Island has been the scene of unusually large epidemics of dengue and chikungunya viruses with Aedes albopictus as the sole vector. After experimental oral infection, Ae. albopictus from La Réunion Island can disseminate both dengue and chikungunya viruses but not the Asian genotype of Zika virus, suggesting a strong midgut barrier to dissemination. Autochthonous transmission of the Asian genotype of Zika virus is improbable on La Réunion Island.
Assuntos
Aedes/fisiologia , Febre de Chikungunya/transmissão , Dengue/transmissão , Mosquitos Vetores/fisiologia , Infecção por Zika virus/transmissão , Zika virus/fisiologia , Aedes/virologia , Animais , Vírus Chikungunya/fisiologia , Vírus da Dengue/fisiologia , Genótipo , Mosquitos Vetores/virologia , Reunião , Zika virus/genéticaRESUMO
Study of the human antibody (Ab) response to Aedes salivary proteins can provide new biomarkers to evaluate human exposure to vector bites. The identification of genus- and/or species-specific proteins is necessary to improve the accuracy of biomarkers. We analysed Aedes albopictus immunogenic salivary proteins by 2D immunoproteomic technology and compared the profiles according to human individual exposure to Ae. albopictus or Ae. aegypti bites. Strong antigenicity to Ae. albopictus salivary proteins was detected in all individuals whatever the nature of Aedes exposure. Amongst these antigenic proteins, 68% are involved in blood feeding, including D7 protein family, adenosine deaminase, serpin and apyrase. This study provides an insight into the repertoire of Ae. albopictus immunogenic salivary proteins for the first time.
Assuntos
Aedes/imunologia , Proteínas de Insetos/análise , Proteínas e Peptídeos Salivares/análise , Animais , Feminino , Humanos , Proteínas de Insetos/imunologia , Proteínas e Peptídeos Salivares/imunologiaRESUMO
Since January 2012, 20 autochthonous cases of dengue virus (DENV) infection have been identified in Réunion. The first cases were detected on the western coast, but the two co-circulating viruses (DENV-1 and DENV-3) seemed to have spread later to different cities of the island. There is a non-negligible risk of increase in viral transmission over the following weeks, so health professionals and public health authorities in Réunion are preparing to face a potential epidemic.
Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Dengue/epidemiologia , Controle de Infecções/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Doenças Transmissíveis Emergentes/transmissão , Dengue/transmissão , Vírus da Dengue/imunologia , Surtos de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reunião/epidemiologiaRESUMO
A major chikungunya outbreak concerned 38% of people living in Reunion Island in 2005-2006. Chikungunya is an arthropod-born-virus disease conveyed by mosquitoes called Aedes albopictus. The health agency in Indian Ocean is responsible for vector control. Previously, in the early 40s, vector control concerned only malaria prophylaxis in La Réunion. Then, during the chikungunya outbreak, a new vector control team was installed and learned from this epidemic. The lessons drawn from chikungunya outbreak in La Réunion are about global executive management and organization linked the local partners and population. The lessons also concern technical topics such as the need of scientific research about vectors and vector-control methods. Finally, the regional cooperation in Indian Ocean (Réunion, Maurice, Seychelles, Comoros, Madagascar) has to be developed to share epidemiologic and entomologic data in order to prevent new chikungunya or dengue outbreak.
Assuntos
Aedes , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Insetos Vetores , Controle de Mosquitos/métodos , Aedes/crescimento & desenvolvimento , Aedes/virologia , Animais , Febre de Chikungunya , Participação da Comunidade/métodos , Participação da Comunidade/tendências , Epidemias , Humanos , Disseminação de Informação/métodos , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/virologia , Aprendizagem/fisiologia , Controle de Mosquitos/organização & administração , Controle de Mosquitos/tendências , Medicina Preventiva/métodos , Medicina Preventiva/organização & administração , Medicina Preventiva/tendências , Reunião/epidemiologia , Fatores de TempoRESUMO
The re-emergence of local transmission of chikungunya virus caused by Aedes albopictus since March 2010 in the Réunion Island, French territory in the southwest Indian Ocean, calls for better epidemiological surveys, vector control, and community-based chikungunya control. This paper describes the strategy and the new ways of vector control applied since the last major chikungunya virus outbreak in 2005-2007, and the high levels of collaboration with mayors and local associations for community involvement. Between March 17, 2010 (first chikungunya case) and July 1, 2010, 313 cases were investigated, 13,036 premises inspected, and 34,393 premises concerned by spatial treatment. The traditional entomologic indices don't explain the distribution map of chikungunya cases, and many other factors have to be measured for evaluating the risk of transmission, such as lifestyle, habitat, and the kind of environment the people live in. A big information campaign was conducted beside the implementation of traditional mosquito control techniques. The two themes of this campaign are environmental management and individual protection, considered as important components of chikungunya prevention. The outcome of the mosquito control strategy demonstrates that community participation is not enough, and more studies are required to define new ways of communication for promoting community-oriented activities to prevent chikungunya epidemics.
Assuntos
Aedes/virologia , Infecções por Alphavirus/epidemiologia , Vírus Chikungunya , Surtos de Doenças , Insetos Vetores/virologia , Controle de Mosquitos/tendências , Vigilância da População , Infecções por Alphavirus/prevenção & controle , Infecções por Alphavirus/transmissão , Animais , Bacillus thuringiensis , Febre de Chikungunya , Vírus Chikungunya/isolamento & purificação , Participação da Comunidade , Eficiência Organizacional , Meio Ambiente , Feminino , Promoção da Saúde , Humanos , Masculino , Controle de Mosquitos/métodos , Controle de Mosquitos/organização & administração , Nitrilas , Controle Biológico de Vetores/organização & administração , Piretrinas , Reunião/epidemiologiaRESUMO
In recent years, the remarkable spread of Aedes albopictus (Skuse) (Diptera: Culicidae) throughout the world has drawn attention to this hitherto poorly studied species, particularly after its role in outbreaks of chikungunya fever in the western Indian Ocean and in Italy. Variants of sterile insect technique (SIT), including the release of transgenic males with a dominant lethal gene (RIDL), have been proposed in the search for new and innovative methods of control. Knowledge of male dispersal, mating behaviour and longevity will be critical to the success of this approach. We present an effective and practical method for trapping both male and female Ae. albopictus using a mouse-baited BG-Sentinel trap.
Assuntos
Aedes/fisiologia , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Controle Biológico de Vetores/instrumentação , Controle Biológico de Vetores/métodos , Animais , Feminino , Masculino , CamundongosRESUMO
On 28 August 2009, French authorities reported five cases of chikungunya fever on Reunion Island: three confirmed, one probable, and one suspected case under investigation. All three confirmed patients presented with an acute febrile syndrome, arthralgia, myalgia and cutaneaous rash. All live in the same area on the western side of the island.
Assuntos
Infecções por Alphavirus/epidemiologia , Vírus Chikungunya/isolamento & purificação , Infecções por Alphavirus/diagnóstico , Infecções por Alphavirus/fisiopatologia , Infecções por Alphavirus/prevenção & controle , Humanos , Controle de Mosquitos , Reunião/epidemiologiaRESUMO
Aedes albopictus is generally considered to have a low vectorial capacity because of its lack of host specificity. Nevertheless, it has been the sole vector of the Chikungunya virus in recent explosive epidemics on the islands of La Réunion and Mauritius. We report on investigations of the seasonal prevalence, container preferences, and geographic distribution of the species on La Réunion. Ae. albopictus showed strong ecological plasticity. In the warm wet season, small disposable containers were the principal urban breeding site, with 1939 positive containers in 750 houses. In the dry winter season, the species remained abundant throughout the island up to 800 m and was present to a maximum altitude of 1200 m. Natural containers were clearly important in this season, although productive sources were hard to find. The preferred natural developmental sites were bamboo stumps and rock holes, over 357 developmental sites observed in peri-urban and gully areas. Generalized logistic models indicated that the optimum sites contained clear water with high organic content and were situated in sites with moderate shade. Our data will provide input into the models of the epidemiology of the disease and design of vector control programs.
Assuntos
Aedes/fisiologia , Aedes/virologia , Cruzamento , Vírus Chikungunya/isolamento & purificação , Insetos Vetores/virologia , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Animais , Demografia , Monitoramento Ambiental , Monitoramento Epidemiológico , Feminino , Humanos , Masculino , Maurício/epidemiologia , Oviposição , Densidade Demográfica , Dinâmica Populacional , Prevalência , Reunião/epidemiologia , Estações do Ano , Especificidade da Espécie , TemperaturaRESUMO
Chikungunya virus (CHIKV) and dengue virus (DENV) are mosquito-borne viruses transmitted by the Aedes genus. Dengue is considered as the most important arbovirus disease throughout the World. Chikungunya, known from epidemics in continental Africa and Asia, has up to now been poorly studied. It has been recently responsible for the severe 2004-2007 epidemic reported in the Indian Ocean (IO), which has caused several serious health and economic problems. This unprecedented epidemic of the IO has shown severe health troubles with morbidity and death associated, which had never been observed before. The two major vectors of those arboviruses in the IO area are Aedes aegypti and Aedes albopictus. The latest is considered as the main vector in most of the islands of the area, especially in Reunion Island. Ae. albopictus showed strong ecological plasticity. Small disposable containers were the principal urban breeding sites, and preferred natural developmental sites were bamboo stumps and rock holes in peri-urban and gully areas. The virus has been isolated from field collected Ae. albopictus females, and in two out of 500 pools of larvae, demonstrating vertical transmission. Experimental works showed that both Ae. albopictus and Ae. aegypti from west IO islands are efficient vectors of dengue and chikungunya viruses. Since 2006 and all along the epidemic of CHIKV, measures for the control of larvae (temephos then Bacillus thuringiensis) and adults (fenitrothion, then deltamethrine) of Ae. albopictus where applied along with individual and collective actions (by the use of repellents, and removal of breeding sites around houses) in Reunion Island. In order to prevent such epidemics, a preventive plan for arboviruses upsurge is ongoing processed. This plan would allow a quicker response to the threat and adapt it according to the virus and its specific vector.
Assuntos
Aedes/virologia , Infecções por Alphavirus/transmissão , Vírus Chikungunya/isolamento & purificação , Dengue/transmissão , Insetos Vetores/virologia , Controle de Mosquitos/métodos , Aedes/crescimento & desenvolvimento , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/veterinária , Animais , Dengue/epidemiologia , Dengue/veterinária , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Insetos Vetores/crescimento & desenvolvimento , Masculino , Oviposição , ReuniãoRESUMO
A literature analysis coupled with new entomological surveys conducted between 2009 and 2012 led to changes in the list of mosquito species present on the island of La Réunion. Using morphological criteria, Orthopodomyia arboricollis is replaced by Or. reunionensis. On the basis of morphometrical and genetic criteria, Culex univittatus is replaced by Cx. neavei. Cx. poicilipes, which was already reported missing 40 years ago, has not been found again. Anopheles arabiensis is confirmed as the only species of the Gambiae complex present on the island. Thus, twelve species are currently known. For each of them, elements of taxonomic, biological and medical interest are listed. An. arabiensis is a major vector of human Plasmodium (last case of indigenous malaria in 1967). In the Indian Ocean, Aedes albopictus and Ae. aegypti both are competent for transmitting dengue and chikungunya viruses. In Africa, Cx. quinquefasciatus transmits Wuchereria bancrofti and Cx. neavei transmits the Sindbis virus; both species also transmit the West Nile virus. Cx. tritaeniorhynchus is the major vector of Japanese Encephalitis virus in Asia. Two species are endemic (Ae. dufouri and Or. reunionensis), the ten other ones are also found in Madagascar and on the African continent (An. coustani, An. arabiensis, Ae. fowleri, Cx. tritaeniorhynchus, Cx. neavei, Cx. insignis, Lutzia tigripes), with three of them having also a cosmopolitan distribution (Ae. aegypti, Ae. albopictus and Cx. quinquefasciatus). Among the twelve recorded taxa, eight species are anthropophilic, three are supposedly zoophilic and one is a predatory species. No new invasive anthropophilic species did settle on the island. Updated identification keys of larval and adult stages are proposed.
Assuntos
Culicidae , Aedes/ultraestrutura , Animais , Anopheles/ultraestrutura , Culex/ultraestrutura , Culicidae/classificação , Culicidae/ultraestrutura , Insetos Vetores/classificação , Reunião , Especificidade da EspécieRESUMO
After a long period of endemicity until the 1950s, the World Health Organization considered autochthonous malaria eliminated from Réunion in 1979. To prevent secondary transmission and re-emergence of autochthonous malaria, permanent epidemiologic and entomological surveillance and vector control measures are conducted. The objective of this study is to report sociodemographic characteristics of imported malaria patients and incidence rates from 2003-2008 using mandatory notification with the aim of identifying risk groups and destinations. During this period, 684 imported malaria cases were reported. Median age of patients was 34.4 years and 22.1% were children = 15 years. Men represented 67.7% of cases and 59.1% of patients reported having taken chemoprophylaxis based on chloroquine alone. Incidence of malaria was considerably different by country destination. For Comoros, incidence was stable and high during the period accounting for 1481 cases per 100000 travels in 2008. The rate was lower for travels to Madagascar, South Africa and Mayotte and decreased over the period to 37, 19 and 3 per 100000 respectively, by 2008. To avoid re-emergence of malaria on the island and to protect themselves, travelers should reduce their risks of acquisition and importation of parasites by using adequate preventive measures. A special preventive program and social mobilisation should be a priority, essentially for the Comorian community in Réunion.