The interactions between entomopathogenic fungi and insects serve a classic example of a co-evolutionary arms race between pathogens and their target host. The cuticle, site of the first contact between insects and entomopathogenic fungus, is an important defensive barrier against pathogens. It is covered by a layer of lipids that appears to play a key role in these processes and cuticular free fatty acid (FFA) profiles are consider as a determinant of susceptibility, or resistance, to fungal infections. These profiles are species-specific. The cockroaches Blattella germanica (Blattodea: Blattidae) and Blatta orientalis (Blattodea: Ectobiidae) are unsusceptible to the soil fungus Conidiobolus coronatus (Entomophthorales: Ancylistaceae) infection, therefore we studied the profiles of FFAs in order to understand the defensive capabilities of the cockroaches. The fungus was cultivated for three weeks in minimal medium. Cell-free filtrate was obtained, assayed for elastase, N-acetylglucosaminidase, chitobiosidase and lipase activity, and then used for in vitro hydrolysis of the cuticle from wings and thoraces of adults and oothecae. The amounts of amino acids, N-glucosamine and FFAs released from the hydrolysed cuticle samples were measured after eight hours of incubation. The FFA profiles of the cuticle of adults, and the wings, thoraces and oothecae of both species were established using GC-MS and the results were correlated with the effectiveness of fungal proteases, chitinases and lipases in the hydrolyzation of cuticle samples. Positive correlations would suggest the existence of compounds used by the fungus as nutrients, whereas negative correlations may indicate that these compounds could be engaged in insect defence.

Aedes aegypti, the primary vector of various arthropod-borne viral (arboviral) diseases such as dengue and Zika, is a popular laboratory model in vector biology. However, its maintenance in laboratory conditions is difficult, mostly because the females require blood meals to complete oogenesis, which is often provided as sheep blood. The outermost layer of the mosquito cuticle is consists of lipids which protects against numerous entomopathogens, prevents desiccation and plays an essential role in signalling processes. The aim of this work was to determine how the replacement of human blood with sheep blood affects the cuticular and internal FFA profiles of mosquitoes reared in laboratory culture. The individual FFAs present in cuticular and internal extracts from mosquito were identified and quantified by GC–MS method. The normality of their distribution was checked using the Kolmogorov-Smirnov test and the Student’s t-test was used to compare them. GC-MS analysis revealed similar numbers of internal and cuticular FFAs in the female mosquitoes fed sheep blood by membrane (MFSB) and naturally fed human blood (NFHB), however MFSB group demonstrated 3.1 times greater FFA concentrations in the cuticular fraction and 1.4 times the internal fraction than the NFHB group. In the MFSB group, FFA concentration was 1.6 times higher in the cuticular than the internal fraction, while for NFHB, FFA concentration was 1.3 times lower in the cuticular than the internal fraction. The concentration of C18:3 acid was 223 times higher in the internal fraction than the cuticle in the MHSB group but was absent in the NFHB group. MFSB mosquito demonstrate different FFA profiles to wild mosquitoes, which might influence their fertility and the results of vital processes studied under laboratory conditions. The membrane method of feeding mosquitoes is popular, but our research indicates significant differences in the FFA profiles of MFSB and NFHB. Such changes in FFA profile might influence female fertility, as well as other vital processes studied in laboratory conditions, such as the response to pesticides. Our work indicates that sheep blood has potential shortcomings as a substitute feed for human blood, as its use in laboratory studies may yield different results to those demonstrated by free-living mosquitoes.

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An assessment of the occurrence and control of pests in hospitals in Poland was carried out in the years 2003-04. The results were also compared with those from a preliminary evaluation carried out in the years 1990-95. The 2003/04 study showed a lower level of infestation in the hospitals examined than previously. The predominant insect pest species was still the German cockroach (Blattella germanica (Linnaeus)), followed by the oriental cockroach (Blatta orientalis L.) and the Pharaoh's ant (Monomorium pharaonis). The use of insect control agents containing permethrin, cypermethrin, deltamethrin and bendiocarb was lower by comparison with the previous study. One reason for this could be that the pesticides were less efficient controls due by the development of resistance. In 2004 respondents noted that alternative formulations as baits, traps, gel baits (containing hydramethylnon, imidacloprid, chlorpyriphos) were used more often than before.

In Poland, out of the 21 species of ticks described, two species have the greatest epidemiological significance: Ixodes ricinus and Dermacentor reticulatus. Their participation in the transmission of etiologic agents of vector diseases such as Lyme disease, tick-borne encephalitis, human granulocytic anaplasmosis, babesiosis, rickettsiosis and many others is widely known. Due to the often severe and sometimes fatal course of diseases transmitted by ticks, a great deal of emphasis is placed on prophylactic activities, minimizing the possibility of biting and transfering pathogens along with the arachnid saliva. In addition to means of personal protection, including appropriate clothing, protective vaccinations, avoiding tick habitats or body checking after returning from this type of places, one of the most important elements of anti-tick prevention is the use of effective repellents. The key role of using the repellent is to discourage the arthropod from attacking and to prevent it from taking food, as a result of which there is no phenomenon of transmission of pathogens from the hematophage to the host organism. The most commonly used substances with arthropod repellent properties are: N-N-diethylm-toluamide (DEET), 3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester (IR3535), icaridine, permethrin and essential oils. However, it should be remembered that no repellent ever protects 100% all the time after application - its use should be considered as one of many elements of personal protection in the prevention of tick bites.