[Aedes albopictus in metropolitan France]

How do attitudes shape protective practices against the Asian tiger mosquito in community gardens in a nonendemic country?

BACKGROUND

The Asian tiger mosquito Aedes albopictus is responsible for the transmission of many arboviruses worldwide and is well adapted to thrive in urban environments. In mainland France, a nonendemic area, this mosquito is responsible for several autochthonous and imported cases of chikungunya and dengue each year. Better management and prevention of mosquito-borne disease transmission in nonendemic areas is thus of global concern. In this context, the aim of this study was to provide a better understanding of mosquito-human interactions as well as human behavior and beliefs in regard to this mosquito species in urban areas.

METHODS

We focused on people who participate in community gardens, which are increasingly popular initiatives in metropolitan France and are conducive to the development of tiger mosquitoes. To evaluate community gardeners' knowledge and practices in relation to mosquito management and control, we conducted a knowledge, attitude, and practice (KAP) survey.

RESULTS

In contrast to previous KAP studies, we showed that attitudes, more than knowledge, influence the practices of community gardeners in relation to mosquitoes. Interestingly, all gardeners who participated in the survey were concerned about the Asian tiger mosquito and were motivated to incorporate mosquito control methods in their gardens. Moreover, mosquitoes were perceived as nuisances rather than disease vector species. A change in community gardeners' perceptions could facilitate more appropriate behavior to control this species.

CONCLUSIONS

This survey reveals the lack of knowledge and awareness of good practices for the efficient control of the Asian tiger mosquito in green urban areas.

Virome Diversity among Mosquito Populations in a Sub-Urban Region of Marseille, France

Some mosquito species have significant public health importance given their ability to transmit major diseases to humans and animals, making them the deadliest animals in the world. Among these, the Aedes (Ae.) genus is a vector of several viruses such as Dengue, Chikungunya, and Zika viruses that can cause serious pathologies in humans. Since 2004, Ae. albopictus has been encountered in the South of France, and autochthonous cases of Dengue, Chikungunya, and Zika diseases have recently been reported, further highlighting the need for a comprehensive survey of the mosquitoes and their associated viruses in this area. Using high throughput sequencing (HTS) techniques, we report an analysis of the DNA and RNA viral communities of three mosquito species Ae. albopictus, Culex (Cx.) pipiens, and Culiseta (Cs.) longiareolata vectors of human infectious diseases in a small sub-urban city in the South of France. Results revealed the presence of a significant diversity of viruses known to infect bacteria, plants, insects, and mammals. Several novel viruses were detected, including novel members of the Rhabdoviridae, Totiviridae, Iflaviviridae, Circoviridae, and Sobemoviridae families. No sequence related to major zoonotic viruses transmitted by mosquitoes was detected. The use of HTS on arthropod vector populations is a promising strategy for monitoring the emergence and circulation of zoonoses and epizooties. This study is a contribution to the knowledge of the mosquito microbiome.

Dengue serosurvey after a 2-month long outbreak in Nîmes, France, 2015: was there more than met the eye?

Clusters of dengue cases have recently become more frequent in areas of southern France colonised by the vector mosquito Aedes albopictus. In July 2015, a 2-month outbreak of dengue virus serotype 1 (DENV-1) was reported in Nîmes. Aim: We conducted a serosurvey in the affected area at the end of the vector activity period to determine the true extent of dengue transmission. Methods: We collected capillary blood from consenting household members, and information on their medical and travel histories, and exposure to mosquito bites. Recent infections were identified using IgM and IgG anti-DENV ELISA, followed, when positive, by plaque reduction neutralisation tests on serum against DENV 1–4 and West Nile virus. The prevalence estimator was calibrated on reference demographic data. We quantified the spatial clustering of dengue cases within the affected community and inferred the transmission tree. Results: The study participation rate was 39% (564/1,431). Three of 564 participants tested positive for DENV-1 infection (after marginal calibration, 0.41%; 95% confidence interval: 0.00–0.84). The spatial analysis showed that cases were clustered at the household level. Most participants perceived the presence of mosquitos as abundant (83%) and reported frequent mosquito bites (57%). We incidentally identified six past West Nile virus infections (0.9%; 95% CI: 0.2–1.6). Conclusion: This serosurvey confirms the potential for arboviral diseases to cause outbreaks − albeit limited for now − in France and Europe.

Low to medium-low risk perception for dengue, chikungunya and Zika outbreaks by infectious diseases physicians in France, Western Europe

Background

Many tropical countries are currently experiencing dengue (DEN), chikungunya (CHIK) and also more recently Zika (ZIKA) epidemics (particularly in Latin America). Although the risk of transmission and spread of these infections in temperate regions remains a controversial issue, vector-borne diseases have been widely reported in the media and have been the focus of preventive strategies by national and international policy-makers and public health authorities. In this context, we wanted to determine the extent of risk perception in infectious diseases (ID) physicians of the current and future risk of arboviral disease introduction, autochthonous case development and epidemic scenarios in France, Western Europe.

Methods

To this aim, we developed an original standardized questionnaire survey which was disseminated by the French Infectious Diseases Society to ID physician members.

Results

We found that ID physicians perceived the risk of introduction and outbreak development of DEN, CHIK and ZIKA in France to be low to medium-low. Generalized Linear Model(s) identified medical school training, the extent of professional experience, and awareness of the French national plan regarding arboviral infections as significant predictors for lower risk perception among respondents.

Conclusion

Despite the fact that arboviral diseases are increasingly being imported into France, sometimes resulting in sporadic autochtonous transmission, French ID physicians do not perceive the risk as high. Better communication and education targeting health professionals and citizens will be needed to enhance the effectiveness of the French national plan to prepare against arboviral diseases.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7317-9) contains supplementary material, which is available to authorized users.

[Mosquito allergy]

Althought serious illnesses can be transmitted by mosquitoes, the most frequent manifestations are due to the contact with saliva of mosquitoes during the blood meal. Culex and Aedes are meeting in countries with moderate climates. Clinical signs vary according to the immunoallergical response, from simple pruritic wheals to immediate and/or delayed allergic reactions. Some reactions can provoke confusion with an infectious cellulitis and an inappropriate antibiotherapy. The natural history of insect bite reactions in an individual tends to progress through 5 stages until immunizing tolerance settles down. Skin prick testing or Serum specific IgE of whole body extracts are lacking sensibility and specificity. Actually, they must be reserved for the most invalidating or severe cases. The recombinant allergens of the saliva of mosquitoes should allow to improve diagnosis and to envisage immunotherapy.

[What's new in clinical dermatology?]

Medical articles published between September 2011 and September 2012 were selected based on themes related to clinical dermatology. Therapeutics, pediatrics, oncology, sexually transmitted diseases, and major system diseases such as sarcoidosis and connective tissue disease were not retained. The subjects reviewed were: (i) epidemiology, particularly the risks of exposure to infectious agents; (ii) diagnostic tools, dominated by dermoscopy and teledermatology; (iii) the description of new disorders and the reassessment of older diseases; (iv) complementary tests in certain types of dermatosis; (v) a few large "works in progress" in dermatology, where clinical aspects and biological research intertwine and contribute one to the other.