Treatment with a neem seed extract (MiteStop®) of beetle larvae parasitizing the plumage of poultry.

Beetles of the species Alphitobius diaperinus, Dermestes bicolor, and Dermestes lardarius may transmit severe agents of diseases on poultry and may in addition harm as larvae the skin and feathers thus leading to severe economic losses. The present study deals with a control measurement using a neem seed extract (MiteStop®) being diluted with tap water. It was shown that spraying of a 1:33 dilution kills both larvae and adults of these part-time parasites as was previously shown for other parasites such as mites, ticks, and blood sucking or biting insects.

Biting and bloodsucking lice of dogs--treatment by means of a neem seed extract (MiteStop®, Wash Away Dog).

Dogs infested with lice belonging either to the group of Mallophaga (hairlings, i.e., Trichodectes canis) or Anoplura (bloodsucking lice, e.g., Linognathus setosus) were washed with the neem seed preparations MiteStop® or Wash Away Dog. It was found that a single treatment with one of these products killed both motile stages and those developing inside eggs (nits) being glued at the hair. In both cases the product had been left for 20 min onto the hair before it was washed away just with normal tap water.

Bluetongue disease in Germany (2007-2008): monitoring of entomological aspects.

In the summer of 2006, a bluetongue epidemic started in the border area of Belgium, The Netherlands, and Germany, spread within 2 years over large areas of Western and Central Europe, and caused substantial losses in farm ruminants. Especially sheep and cattle were severely affected, leading to a case-fatality ratio of nearly 40% in sheep (Conraths et al., Emerg Inf Dis 15(3):433-435, 2009). The German federal ministry of food, agriculture, and consumer protection (BMELV) established a countrywide monitoring on the occurrence of the vectors of this virus, i.e., midges (family Ceratopogonidae) of the genus Culicoides. The monitoring was done on 91 sites, most of which were localized in the 150-km restriction zone that existed in December 2006. A grid consisting of 45 x 45 km(2) cells was formed that covered the monitoring area. As a rule, one trap was placed into each grid cell. The monitoring program started at the end of March 2007 and lasted until May 2008. It included the catching of midges by ultraviolet light traps-done each month from days 1 until 8, the selection of midges of the Culicoides obsoletus, Culicoides pulicaris group, and other Culicoides spp., the testing of midges for bluetongue virus (BTV) by polymerase chain reaction (PCR), and the daily registration of weather data at each trap site for the whole monitoring period. The following main results were obtained: (1) Members of the C. obsoletus group were most commonly found in the traps, reaching often 3/4 of the catches. The African and South European vector of BTV-the species Culicoides imicola-was never found. (2) Members of the C. obsoletus group were most frequently found infected with BTV besides a few cases in the C. pulicaris group and other species. (3) Members of the C. obsoletus group were also found in winter. Their numbers were reduced, however, and they were caught mostly close to stables. Therefore, a true midge-free period does not exist during the year in Germany. (4) The amounts of midges caught daily depended on the weather conditions. If it was cold and/or windy, the traps contained only a few specimens. Since the months from January to May 2008 were considerably colder (at all farms) than their correspondents in 2007, the growing of the population of midges started 2-3 months later in 2008 than in 2007. (5) The highest populations of midges occurred in both years (2007 and 2008) during the months September and October. This corresponded significantly to the finding of highest numbers of infected midges and to the number of diseased cattle and sheep during these 2 months. (6) It is noteworthy that in general, the first virus-positive midges of the species C. obsoletus were found about 1 1/2 months later than the first clinical cases had occurred or later than the first PCR-proven virus-positive sentinel animals had been documented. In 2007, the first BTV-positive cattle were detected in May in North Rhine-Westphalia, while the first positive Culicoides specimens were only found in August on the same farm. Evaluating these main results of the entomological monitoring and the fact that many wild ruminants have also been infected with BTV, it becomes evident that bluetongue disease has become endemic in Central Europe, and that only constant effort including vaccination and perhaps also insecticidal protection of cattle and sheep will keep the economical losses at a reasonable level. The following papers (1-10) in this journal will contribute more details obtained from this worldwide unique entomological monitoring: Bartsch et al. 2009; Bauer et al. 2009; Stephan et al. 2009; Clausen et al. 2009; Hörbrand and Geier 2009; Kiehl et al. 2009; Mehlhorn et al. 2009; Kiel et al. 2009; Vorsprach et al. 2009; Balczun et al. 2009.

The European vectors of Bluetongue virus: are there species complexes, single species or races in Culicoides obsoletus and C. pulicaris detectable by sequencing ITS-1, ITS-2 and 18S-rDNA?

When studying the vectorship of Culicoides species during the outbreak of Bluetongue disease (BTD) in Central Europe, the question arose whether the most common species and additionally proven vectors of BTV (C. obsoletus and C. pulicaris) are definitive species or do they belong to so-called complexes, since the determination based on morphological criteria is not very significant and knowledge on the life cycles is poor or even absent. Therefore, the present molecular biological study on their ITS-1, ITS-2 and 18SrDNA characteristics was initiated to investigate specimens, which had been determined by their wing morphology during an entomological monitoring in the years 2007 and 2008 at 91 farms in Germany (Mehlhorn et al. 2009). This study revealed novel types respectively different forms, which appeared very similar to Culicoides obsoletus, but showed slightly varying wing patterns. The molecular biological data were compared to those in data banks and combined to provisional dendrograms. The ITS-1 and ITS-2 analysis showed that the specimens determined in the monitoring as C. obsoletus inclusive those with different wing pattern correlate significantly with the data of C. obsoletus in the data banks and surrounded the data bank specifications of C. montanus and C. scoticus so closely that the latter might be only hardly separate species. A similar interpretation can also be drawn when looking at the 18S rDNA dendrogram. Thus, C. scoticus and C. montanus might be races of C. obsoletus rather than separate species. With respect to the ITS-1 and ITS-2 characteristics of C. pulicaris females, which morphologically and by size can be significantly differentiated from C. obsoletus, it was seen that this species is significantly situated on another rame of the dendrograms and in very close relationship to C. punctatus and C. lupicaris, so that the latter might also be only races of C. pulicaris. One of the two other most common species found in Northrhine-Westfalia-C. festivipennis-belongs to the rame of the dendrogram, where C. pulicaris is situated close to C. circumscriptus, while the other common species (C. nubeculosus) has its place close to C. puncticollis and C. variipennis on the rame, where C. obsoletus is found. Thus, this paper again clearly points out that the question "what is a definite species" is far from being solved, if the life cycle is not defined and morphology misleading. However, it also became clear that C. obsoletus and C. pulicaris are Europe-wide occurring species and that several other clearly described separate species are probably only races.

Entomological survey on vectors of Bluetongue virus in Northrhine-Westfalia (Germany) during 2007 and 2008.

The entomological monitoring programs done on 19 farms all over Northrhine-Westfalia (Germany) in the years 2007 and 2008 showed that the species Culicoides obsoletus and C. pulicaris are the most common ones and that both act as vectors of the bluetongue-virus of the serotype 8. Especially the species C. obsoletus was found all over the year and also inside or close to stables during the winter months. Therefore, there exists no midge-free period that would interrupt the transmission cycle of bluetongue virus. This makes it necessary that vaccination programs and insecticidal treatment have to consider this and must be preceded even in winter months. From the fact that there was no northward migration of southern Culicoides species (e.g., Culicoides imicola), apparently, globalization and its intense transportation of animals, plants, and other goods is the reason of this BTD outbreak in Central Europe. This conclusion needs urgently special attention on other luring epidemics in the near future.

Effects of permethrin (Flypor) and fenvalerate (Acadrex60, Arkofly) on Culicoides species-the vector of Bluetongue virus.

Bluetongue disease struggles ruminants in Europe since summer 2006, introducing high levels of morbidity and mortality. Besides vaccination, the application of insecticides is another means to protect cattle and sheep from infections with the Bluetongue virus, which is transmitted in Europe by female specimens of Culicoides species (Culicoides obsoletus and in a few cases of Culicoides pulicaris and Culicoides dewulfi). The present study deals with the effects of permethrin (Flypor) and fenvalerate (Arkofly, Acadrex 60) on freshly caught Culicoides specimens when brought into contact for 15, 30, 60 or 120 s with hair of cattle or sheep treated topically 7,14, 21, 28 or 35 days before. The experiments clearly showed that the lege arte application of these compounds (products) onto the hair of the experimental animals succeeds in killing Culicoides specimens when brought into contact with hair from feet of animals being treated even 35 days before. This test was needed to make sure that the products do reach the feet and belly of the animals in sufficient amounts, since this region is the predominant biting site of the Culicoides midges.

Pilot study on deltamethrin treatment (Butox 7.5, Versatrine) of cattle and sheep against midges (Culicoides species, Ceratopogonidae).

Deltamethrin (Butox 7.5, Versatrine)-treated hair of cattle and sheep were brought into contact for 15, 30, 60, or 120 s with freshly caught Culicoides specimens, which are the vectors of the Bluetongue virus. The hair was clipped off from the treated animal just above the claws-a region which is one of the predominant biting sites of the midges. Hair obtained on day 7, 14, 21, 28, or 35 after treatment were mingled with the Culicoides specimens for the given contact periods. After separation of the midge from the hair and placing them onto white filter paper in a petri dish, their fate was followed for the next hours by microscopic inspection. It was found that deltamethrin (in both formulations Butox, Versatrine) reaches for 35 days in such sufficient amounts in the hair of the legs to kill attacking specimens of Culicoides in reasonable short periods after very short contacts. The observed speed of kill and the deleting effects were so quick that the midges very probably would not bite before their death.

Outbreak of bluetongue disease (BTD) in Germany and the danger for Europe.

In August 2006, the blue tongue virus (BTV-type South Africa serotype 8) was detected for the first time in cattle blood probes in the Netherlands, immediately followed by cases in Belgium and in cattle on German farms, which were situated close to Aachen at the border to those countries. Within less than 2 months the disease spread eastwards crossing the Rhine, southwards to Luxemburg and to Northern France. At the end of the year 2006, nearly 1,000 farms were affected in Germany. Catches on two German cattle farms proved that the ceratopogonid species Culicoides obsoletus was obviously the vector, since many females-fed and unfed ones-were found to be infected with this virus. This sudden outbreak of bluetongue disease (BTD) is surely not a primary result of global warming, but rather an effect of globalization-i.e. the intensive worldwide import and export of animals; but a hot summer, as in 2006, and a warm winter like that of the years 2006/2007 supported the new spread starting again in masses in August 2007 leading to 596 PCR-confirmed cases until then with more than 200,000 animals infected. Thus, new agents coming from elsewhere have only a chance to spread if appropriate vectors are available and the conditions remain favourable during a reasonably long period. Effects of global warming-of course-will support persistence of such outbreaks of diseases due to offering of spreading of imported viruses, bacteria and/or parasites.

Efficacy of Oxyfly on Culicoides species--the vectors of Bluetongue virus--and other insects.

The efficacy of the insecticide Oxyfly (active compound lambda-cyhalothrin) was tested against specimens of Culicoides species-the vectors of Bluetongue virus-and other insects. Living specimens of the insects were brought into contact for at least 10-15 s with treated wooden plates and the extinction period of the insects was followed over the next minutes or hours. It turned out that this rather short contact was sufficient to kill the Culicoides specimens in minutes and the other insects in a few hours even if the plates had been impregnated 9 weeks before.

Effects of Bayofly on specimens of Culicoides species when incubated in hair taken from the feet of previously treated cattle and sheep.

Sheep and cattle were treated with Bayofly pour-on containing 1 g cyfluthrin per 100 ml ready-to-use solution. Seven, 14, 21 and 28 days after treatment, hair was clipped off from the back and feet and mixed for 10-15 s, 30 s, 1 or 2 min with freshly caught Culicoides midges. It was found that the insecticide on hair from the legs--the predominant biting site of midges--had a significant killing effect on Culicoides for 3-4 weeks, even after a short-term contact.

First occurrence of Culicoides obsoletus-transmitted Bluetongue virus epidemic in Central Europe.

In August 2006, Bluetongue virus disease (BTD) was detected for the first time in the Netherlands, Belgium, Germany and Northern France. Serological tests as well as reverse transcriptase polymerase chain reaction (RT-PCR) proved the occurrence of Bluetongue virus (BTV) in diseased sheep and cattle, and the virus was identified as serotype 8. Therefore, the search for possible vectors was immediately initiated in the outbreak region in Germany. Traps with automatically regulated ultraviolet light lamps were placed at two different farms with sero-positive cattle, and insect monitoring was done from August 2006 until January 2007. The caught arthropods were weekly determined, and it could be observed that midges of the dipteran family Ceratopogonidae occurred in large numbers, sometimes representing up to 40% of all individuals. The microscopical analysis of the wing morphology showed that the species (complex) Culicoides obsoletus was most abundant covering about 97% of the analysed midges. On the second place ranged C. pulicaris, while C. nubeculosus and C. festivipennis were found only as single individuals. Fed and unfed females were separated, sent to the National Reference Laboratory for Bluetongue disease (Friedrich-Loeffler-Institut, Isle of Riems, Germany) and investigated with a BTV-8-specific real-time RT-PCR. It could be demonstrated that at both farms both fed and unfed C. obsoletus were tested positive for BTV-8 genomes, while none of the other species scored positive. This finding strongly supports that the BTD-epidemic, which reached in the meantime wide regions of North Rhine-Westphalia in Germany and of the neighbouring countries with several hundreds of affected farms, is initiated by virus transmission during the blood meal of midges of the C. obsoletus complex. Since they were captured still at the 21st of December close to cattle with clinical signs, it must be feared that BTV-8 is now established in Central Europe, where it had been absent until now.