[In vitro efficacy of three novel delousing formulations against the head louse (Pediculus capitis L.)]. / Ucinnost trí nových odvsivovacích prípravku na ves detskou (Pediculus capitis L.) v in vitro testech--krátké sdelení.

A total of 498 head lice (2nd and 3rd instar larvae, females and males) combed out of the hair of 38 children, were exposed to the delousing formulations Diffusil H Forte Spray (carbaryl 1%), Diffusil Care (isopropyl myristate, cyclomethicone, and dimethiconol) and Paranit (coconut oil, anise oil, and ylang ylang oil) in in vitro tests. The first two formulations, i. e. Diffusil H Forte Spray and Diffusil Care, caused 100% mortality of exposed lice, while Paranit only killed 12.2% of exposed lice.

[Effectiveness of aerial application of VectoBac G larvicide granules against mosquitoes in the Olomouc region in spring 2006]. / Ucinnost letecké aplikace granulovaného larvicidu vectobac G proti komárum na jare 2006 v Olomouckém kraji.

In the spring 2006, a flood emergency occurred in the Olomouc region after a rapid snow thaw, with the formation of multiple periodic pools and overflows persisting for long periods. In the floodplain forests, as expected, mass occurrence of adult mosquitoes was observed, infesting the nearby villages. The mosquito emergency continued until August and mosquitoes of both the spring species, in particular, Ochlerotatus cantans, and summer species were implicated in it. To control this emergency, aerial application of VectoBac G larvicide granules based on Bacillus thuringiensis var. israelensis (BTI) at a dose of 6.4 kg/ha was used for the first time in the Olomouc region. Its efficacy was close to 100 % for the treated water areas. The effect was clearly evident in the communities situated in the vicinity of the treated breeding grounds. Nevertheless, not all breeding grounds and blind stream meanders could be treated aerially. As a result, mosquitoes from the untreated breeding grounds caused an emergency in the nearby communities where insecticide aerosols had to be applied on a large scale, even repeatedly in some cases. The treatment of the mosquito breeding grounds with BTI based larvicide granules proved to be an effective and fully selective approach to controlling mosquitoes. Although the technology is exacting and requires professional and organizational skills, it is expected that, in the Czech Republic, this environmentally friendly approach to mosquito control will replace the large scale use of non-selective chemical aerosol insecticides. The public health protection, administrative and legislative authorities should be active in promoting the use of specific BTI based larvicides for the treatment of mosquito breeding grounds, even if located in protected areas, whenever it is needed for mosquito control in emergencies.

[Pediatric head lice: taxonomy, incidence, resistance, delousing]. / Ves detská: systematika, výskyt, rezistence, odvsivování.

Based on the current knowledge, head louse (Pediculus capitis) and body louse (Pediculus humanus) are two different species that infest specific parts of the human body and do not interbreed in vivo. In 1991-2002, 6 257 cases of pediculosis were reported in the Czech Republic while 3 138 000 pediculicide packagings, i.e. about 500 times as many as the number of cases, were marketed. Between October 2004 and February 2005, a total of 531 children aged between 6 and 15 years from 16 selected schools in the Zlín and Olomouc regions were screened by dry hair combing. Living lice were detected in 14.1% of the enrolled children and dead nits alone were observed in other 9.8% of the subjects. In vitro tests revealed that the collected head lice were highly resistant to malathion, the active ingredient of Diffusil H 92 M. The number of reported cases of pediculosis roughly doubled in 2005.

[Problems related to control of epidemic and persistent outbreaks of scabies]. / Problémy protiepidemické práce pri epidemickém a protrahovaném výskytu svrabu.

Experience with control of epidemic and persistent outbreaks of scabies in collectives is presented. Both diagnosis and patient's compliance may pose problems. When diagnosing scabies, not only clinical symptoms but also the dynamics of the spread among persons in collective facilities such as social care and psychiatric in-patient centres should be taken into account and efficacy of the antiscabies medication should be followed up. If diagnosis of scabies is confirmed, it is crucial to prescribe an effective antiscabies medication and to ensure the patient's compliance with treatment, including thorough washing of the body each time before application of the medication, throughout the whole treatment period instead of treating only the symptoms of secondary eczema.

A resistance of head lice (Pediculus capitis) to permethrin in Czech Republic.

An outbreak of pediculosis at primary schools was recorded in the Czech Republic in 1992. Almost 20% of children in some schools were infested. This outbreak can be attributed to the resistance of head lice to permethrin, which has not been mentioned in literature yet. The resistance factors established in three towns range between 2 and 385 and between 5 and 557 for LC50 and LC90 values, respectively. This resistance has developed after exclusive use of pyrethroids lotion and shampoo in the Czech Republic since 1978, and it was accompanied by a cross-resistance to d-phenothrin and bioalethrin. But the susceptibility of head lice to malathion and pirimiphos-methyl in 1992 was very similar to that found in 1981. The lotion containing 0.3% of malathion (Diffusil H92 M) has been fully effective against the resistant lice. When introduced into the practice, it quickly reduced the infestation of children in primary schools. The other lotion and shampoo containing 0.3% and 0.7% of pirimiphos-methyl respectively were found to be effective as well.

[Variations in the occurrence of Borrelia in the tick, Ixodes ricinus (L.) in the Olomouc District]. / Kolísání výskytu borelií u klístete Ixodes ricinus (L.) v okrese Olomouc.

Examinations of 1,998 ticks Ixodes ricinus in the district of Olomouc revealed 182 cases of borrelia, i.e. in 9.1% ticks. Prevalence in males is 10.7%, in females 12.8% and in nymphs 7.0%. A certain coincidence was observed between mosquito incidence, in particular during the first half of the year, and borrelia prevalence in ticks in the course of the following year, with prevalence variations manifested in tick imagos only. A hypothesis is formulated that mosquitos feeding on larger animals, who are often attacked by nymphs of I. ricinus ticks, can increase the infection rate in the hosts by borrelia transmission and thus participate in the increase of tick imago prevalence during subsequent years.

[Long-term study of natural foci of tick-borne encephalitis in the District of Olomouc]. / Dlouhodobé sledování aktivity prírodních ohnisek klíst'ové encefalitidy v okrese Olomouc.

The incidence of natural foci of tick-borne encephalitis in the Olomouc district has been characterized as general. This finding is based on analyses of results of earlier reports and results of serological blood tests of 397 small mammals from localities where probably transmission of the infection to humans occurred. The incidence almost corresponds to the incidence of the tick Ixodes ricinus. It has a long-lasting and also cumulative character; the number of reported cases from the main focal areas is proportional to the frequency of localities infestated with Ixodes ricinus ticks, assuming an approximately equal number of visitors in the woods of the district.

[Findings of body lice (Pediculus humanus L.) in Czechoslovakia]. / Nález vsi satní (Pediculus humanus L.) v Ceskoslovensku.

The first finding of body lice in Czechoslovakia since year 1945 is demonstrated. The determination of the species is based on the location of the louse on the body of the infested person and on the significant differences in the length of tibia of middle legs in these lice and those collected from the head of children. Local eradication was achieved by using formulation containing permethrin, against head lice.

[Control of Monomorium pharaonis using a methoprene bait in the Berlin Zoo and its combined application with a residue insecticide in the Olomouc Children's Clinic]. / Die Bekämpfung von Monomorium pharaonis mit einem Methoprenköder im Tierpark Berlin) und dessen kombinierte Anwendung mit einem Rückstandsinsektizid in der Kinderklinik Olomouc.

The control of Monomorium pharaonis by a methoprene bait in the Tierpark Berlin and its combined application with a residue insecticide in the children's hospital in Olomouc. In two different institutions heavy infestations with the Pharaoh's ant (Monomorium pharaonis L.) could be eradicated with a methoprene bait applied by different methods. In a zoological garden the bait was continuously exposed in boxes for many weeks. The dosage was about 2.5 g/10 m2, and 1.42 kg of DYBH-bait were used. On average 50% of this amount was taken off by the ants during the eradication period of 14...37 weeks. In a children's hospital after spraying permethrin 10 weeks before the bait was exposed uncovered with 0.5 g per bait station. Within 13 days an area of 9,000 m2 was treated with about 1.8 kg of DYBH-bait. 131/2 weeks after the beginning of the application no more ants could be detected by visual checking. Further checking with baited traps after 128 days confirmed eradication. The bait was very persistent being still attractive and effective after an exposition of about 8 months.

Susceptibility to DDT and some other insecticides of head lice (Pediculus capitis De Geer) in Czechoslovakia.

For testing the susceptibility of the head louse to insecticides impregnated bunches of polyamide fibres, whose diameter resembled that of human hair (0.1 mm) were used. In this manner a low mortality of control lice collected from infected persons was obtained (2.9% after 16 hours of exposure). Even after 25 years of DDT use no apparent resistance could be demonstrated in 25 tested louse populations and cross resistance to permethrin in 7 tested populations. The diagnostic concentration for resistance to pp'-DDT was established at 1%. Of the tested insecticides the highest toxicity was shown by malathion (LC50 = 0.000 018%), pirimiphos-methyl had on average a twice lower toxicity, trichlorphon 104 times lower, tetramethrin 1220 times lower, permethrin 2.5 times lower and pp'-DDT 630 times lower toxicity.

Effectiveness of methoprene-impregnated baits in the control of Monomorium pharaonis ant populations infesting health establishment and households.

The use of baits consisting of dried egg yolks and impregnated with 0.5% of methoprene, loosely applied twice within 8-12 days at the rate of 1 g of bait per 3-6 m2 of floor surface area at each application was found to result consequently in a complete eradication of M. pharaonis ant populations in two medium-size health establishments and in one apartment house. Under more favorable conditions in another health establishment the use of methoprene-impregnated baits applied twice at the average dose of 1 g per as many as 46 m2 floor area proved equally effective in ensuring permanent eradication of ants. Providing that all colonies on the premises can be affected by bait a complete eradication of ants can be expected within 100 days after the first application of bait.

A further member of the Yucaipa group isolated from the common wren (Troglodytes troglodytes).

In 1977, 477 small birds of 52 species were virologically examined. Five cloacal swabs from Troglodytes troglodytes yielded two paramyxovirus strains which were found antigenically related to, but not identical with Ch/Yucaipa/California/56 virus according to three serological tests. The ecological significance of these findings and the possibility of paramyxovirus classification into four types are discussed.

Isolation of Tettnang virus from ticks, mosquitoes and small rodents.

Seven strains of Tettnang virus were isolated in Czechoslovakia: 3 from Ixodes ricinus tick nymphs, males and females, one from Dermacentor reticulatus tick females, one from Aedes cantans mosquitoes and two strains from the brains of Clethrionomys glareolus and Apodemus flavicollis small rodents.

Pyemotes herfsi (Oudemans, 1936) as causative agent of another mass dermatitis in Europe (Acari, Pyemotidae).

The authors describe new cases of human dermatitis caused by Pyemotes herfsi occurring in the food mixing shed for the farrowing house in the piggery at a farm in the destrict of Olomouc, where seven persons handling feedstuff were infected. The disease became manifest as a papular rash, appearing particularly on the back, and all over the body except on the hands and face. When the afflicted person discontinued work in the feed mixing shed, the rash disappeared quickly. The mites were found in the granular dust accumulated in the loft above the food mixing shed. The initial host (insects) could not be identified. After cleaning and disinsecting the contaminated premises with Metation E 50 the workers were free from any symptoms. The mites of the genus Pyemotes, particularly the species P. herfsi (Oudemans, 1936) are little known, but probably frequent causative agents of human dermatitides.

A study on the role of birds in the spread of infections.

During three expeditions undertaken in March 1977 to June 1978, 797 cloacal swabs were collected from birds of 54 species. Seven salmonella strains of six serotype were isolated from Larus ridibundus (five strains), Corvus frugilegus and Acrocephalus schoenobaenus (one each). Four strains of influenza A (HAV2 NA4V) virus were isolated from Larus ridibundus. For the first time in Czechoslovakia, two strains of Yucaipa paramyxovirus were isolated, both of them from Troglodytes troglodytes. These results are the first contribution to a study on the role of birds as hosts and vectors of different bacterial and viral agents.

Isolation of Tettnang virus from Ixodes ricinus ticks in Czechoslovakia.

Three virus strains closely related to Tettnang virus were isolated from nymphs and males of Ixodes ricinus tick in Moravia and Slovakia. The virus isolates were lethal for suckling mice on intracerebral (i.c.) inoculation but the virus titres in the brain were low. The incubation period of 5--12 days in the first mouse passage was shortened to 3 days in further passages. Infection of mice was accompanied by ultrastructural changes in the cytoplasm of neurons. Groups of spherical virus particles 75 to 80 nm in diameter occurred within simple vacuoles.

Findings of yersinia in rats and sewer rats.

Survey of first methodical experiences in the microbiological examination of sewer rats Rattus norvegicus and rats Rattus rattus for yersiniae. From total of 178 cadavers 30 yersinia cultures were isolated, including 4 Yersinia pseudotuberculosis serotype III strains. Yersinia enterocolitica serotype O3 was isolated only from rats Rattus rattus in pig houses. Importance of suitable treatment of cadavers (at best in frozen state) and their quick delivery to the laboratory is being discussed.

Effectiveness of fenitrothion for area control of ticks Ixodes ricinus (L.).

Susceptibility to fenitrothion in all stages of unfed ticks Ixodes ricinus increases with their age and this fact is reflected in the effectiveness of various dosages of insecticides applied for area control. The following minimum, but fully effective dosages of the dust Metation P-5 and the spray Metation E-50 (both preparations contain fenitrothion) for application in separate seasons have been ascertained: In September and October 1 kg of fenitrothion per ha of treated area ensures complete control of unfed ticks until the winter of current year. In Aril 3 kg of fenitrothion per ha is necessary, if tick control is to be ensured until the appearance of the new generation, i.e. until the end of August. In May the control of unfed ticks is ensured by 1 kg of fenitrothion per ha, in June to August by 0.3 kg per ha is fully efficacious.