The invasive mosquito Aedes albopictus (Diptera, Culicidae) firstly recorded in Bohemia, Czech Republic.

STUDY OBJECTIVE: In 2016-2017, the monitoring of possible introduction of an invasive mosquito species, the Asian tiger mosquito Aedes (Stegomyia) albopictus (Skuse, 1894) (Diptera, Culicidae), was conducted in eastern, southern, central and western parts of Bohemia, Czech Republic. MATERIAL AND METHODS: The focus was placed on local major traffic arteries (motorways D1, D3 and D5 and an expressway E49), which connecting South Europe and some of Balkan countries, infested by Ae. albopictus, with the Czech capital Prague. In total, more than 100 ovitraps were placed on 16 study sites - close surroundings of refuelling gas stations and neighbouring parking lots. RESULTS: In August and September 2017, totally eight specimens of Ae. albopictus were collected at the ovitrap site near Mezno/Mitrovice, Central Bohemia on D3 motorway and other two specimens were recovered at the gas station near Rozvadov, West Bohemia on D5 motorway. On the other hand, Ae. albopictus was not recorded on a main Czech motorway D1 connecting Prague and Bratislava capitals during the monitoring. CONCLUSION: The introduction of this mosquito into the Czech Republic is known since 2012 from surroundings of Mikulov town (South Moravian Region), our records were then the first in the region of Bohemia. Moreover, the distance between positive localities shows the potential for Ae. albopictus to be introduced by ground transport anywhere within the Czech Republic.

Laboratory evaluation of repellency of traditional Czech homemade repellents against Aedes aegypti.

OBJECTIVES: In the Czech Republic, autochtonous transmission of mosquito borne diseases is not common; however, the need for personal protection should not be underestimated. Many people still rely on homemade repellents utilizing recipes based on local folk wisdom that are published annually in local Czech media. Despite minimal disease risk, nuisance biting and potential allergic responses make it essential to evaluate the chemical composition, effect, and duration of four homemade repellents often used and determine the necessity for public health education on application and use of alternative repellent products. METHODS: A review of local web-based media was conducted to identify the most commonly advertised homemade repellent products. The top four products were rosemary (Rosmarinus officinalis), sagebrush (Artemisia absinthium), walnut-tree (Juglans regia) leaves and clove (Syzygium aromaticum). These repellents were then prepared following the published recipes to evaluate their repellency effects, and reveal potential allergen presence. A bioassay against Aedes aegypti was conducted on ten volunteers for each repellent and the chemical composition was detected using gas chromatography. RESULTS: Significant initial repellency effect was found in mixtures of the clove (73.1%) and walnut leaves (49.0%) with ALPATM herbal embrocation after 10 minutes. The efficacy decreased to 46.5% and 34.3 % after 30 minutes, respectively; and, 30.3 and 18.2%, 60 minutes after the application. The remaining two samples, Rosmarinus officinalis and Artemisia absinthium solutions, exhibited no significant effects against Ae. aegypti. The evidence of allergens including cinnamic aldehyde, eugenol and coumarin were detected indicating potential concerns for product safety. CONCLUSION: The homemade repellents reviewed were either ineffective or had unstable repellency effect within one hour. The low efficacy of these products may be appropriate to decrease nuisance biting, but should not be considered for primary prevention against mosquito borne diseases in areas with active disease transmission. Additionally, more research is needed to assess rates of allergic responses to homemade repellent products.