Genetic characterization of Plasmodium vivax in the Kyrgyz Republic.

At the end of 2016, Kyrgyz Republic was certified by the World Health Organization as a malaria-free country, while only a decade ago this disease posed a serious health threat. The progress achieved by Kyrgyz Republic provides a unique example of tertian (Plasmodium vivax) malaria elimination. This success was based on an integrated approach, including measures for the treatment of infected people and disease prevention, vector control and the development of an effective national epidemiological surveillance system. Lower P. vivax msp-1, msp-3α, csp and dbpII genes polymorphism was revealed in Kyrgyz Republic in compare with that in Tajikistan. Molecular characterization of the causative agent found that P. vivax populations in Kyrgyz Republic was comprised by several lineages, highly divergent in the south-western and genetically homogeneous in the northern regions of Kyrgyz Republic, d. Such profile in the northern regions was compatible with several recent introductions rather than a long-term endemic circulation of the parasite. A low level of genetic variability suggested that the parasitic systems of tertian malaria, were not adapted, which, along with other factors, largely determined the possibility of malaria elimination in northern Kyrgyz Republic. Other determinants included environmental, social, and epidemiological factors that limited the spread of malaria. South-western Kyrgyz Republic, a region with a high level of interstate migration, requires considerable attention to prevent the spread of malaria.

SCIENTIFIC AND PRACTICAL STUDIES OF MALARIA IN THE CIS COUNTRIES AND GEORGIA.

The paper presents the scientific studies of malaria pathogens and vectors, which have been specially conducted in the endemic areas of the CIS countries and Georgia for use in an epidemiological surveillance system. The main ones investigate the structure of malaria foci and the level of G-6-PD deficiency among residents, determine the malariogenic potential. of the territory and the risk of infection in the population, and specify the taxonomy, systematics, and spread of major malaria vectors in .the countries ofWHO European Region. In addition, the time and magnitude of manifestations of long-term post-incubation tertian malaria were established; th6 susceptibility of P.vivax to antimalarials and the levels of resistance and irritability of malaria vectors to insecticides were studied. The experience in using a geographic information system for the epidemiological surveillance of malaria is given.

THE SPECIES-SPECIFIC AND ENVIRONMENTAL CHARACTERISTICS OF THE LARVAL BIOTOPES-OF MALARIA MOSQUITOES IN THE SOUTH OF EUROPEAN RUSSIA.

Five Malaria mosquito species anopheles atroparvus, An.claviger, An.hyrcanus, An.maculipennis, and An.messeae were found in the study habitats in the south of European Rausia. The dominahce indices and environmental preferendes of co- inhabiting species were deterinined. The major potential malaria vectors in the south of European Russia were An messeae (in the valleys) and An.maculipennis (in the highlands and foothills). There was new evidence for chromosoml variability in the malaria mosquitoes An. atroparvus and An.maculipennis. The new inversion 3Roi (23B-27C) was identified in An.maculipennis.

[Chromosomal polymorphism in the populations of malaria mosquito Anopheles messeae (Diptera, Culicidae) in the Volga region].

We studied the species composition and chromosomal variability of malaria mosquitoes in the Volga Basin (Upper, Middle, and Lower Volga regions). We investigated larvae karyotypes of sibling species of the Anopheles maculipennis group. We calculated the frequencies of chromosomal inversions in the local populations of the dominant species An. messeae. We discovered that karyotypic structure of An. messeae populations depends on landscape-climatic zones. Populations of the Upper, Middle and Lower Volga differ in frequency of chromosome inversions XL, 2R, 3R, and 3L.

[Behavioral features of the imago of malaria mosquitoes (Diptera, Culicidae, Anopheles) in uzbekistan].

Morphological, cytogenetic, and molecular genetic analyses made in the Fergana, Chirchik-Akhangaran, Mirzachul, and Zarafshan physicogeographical districts of Uzbekistan revealed the closely related species An. artemievi malaria mosquito from the An. maculipennis complex. In the human settlements and natural biotopes under their canopy of 7 physicogeographical districts of Uzbekistan, there were 6 Anopheles mosquito species (An. artemievi, An. claviger, An. hyrcanus, An.martinius, An. pulcherrimus, and An. superpictus); An. superpictus is a dominant species in the human settlements and An. artemievi in subdominant. An.pulcherrimus was dominant and An. superpictus was subdominant under natural canopy conditions. The latter is of widespread occurrence in the mountain and piedmont areas of Uzbekistan. It is encountered in all the physicogeographical districts. An. artemievi is distributed in the river valleys in the Fergana, Chirchik-Akhangaran, Mirzachul, and Zarafshan physicogeographical districts. An. pulcherrimus is common in the plain river valleys, except in the Qashqadaryo physicogeographical district. An. martinius is found in the Qashqadaryo and Nizhneamudryo physicogeographical districts. Livestock houses are the most attractive day's rests for mosquitoes; utility rooms rank next in mosquito density. Housing premises are slightly occupied by mosquitoes. The maximum size of aggressive mosquitoes is noted in July, August, and early September.

[The species and karyotype composition of malaria mosquito larvae in different water reservoirs of the city of Moscow].

The species and karyotype composition of malaria mosquito larvae was investigated in different water reservoirs of the city of Moscow. Cytogenetic analysis identified 2 malaria mosquito species: An. maculipennis Mg and An. messeae Fall. An. messeae was predominant in all the biotopes studied. The proportion of An. maculipennis varied from 0 to 23.8% and averaged 6.27%. An. messeae larvae were found to have chromosomal polymorphism. Individual local An. messeae populations having a definite, historically established, time and space resistant karyotype structure were shown to form in Moscow. The resistance of the karyotype structure of the populations was provided by reversible fluctuations in the rate of chromosomal inversions.

[The distribution of the mosquitoes of the Anopheles maculipennis complex (Diptera, Culicidae, Anophelinae) in Central Asia].

The polymerase chain reaction-restriction fragment length polymorphism method, cytogenetic analysis, and investigation of egg exochorion have indicated that three representatives of the Anopheles maculipennis complex (subgenus Anopheles): An artemievi Gordeev et al., An. messeae Falleroni, and An. marinius Shingarev. An. messeae is a European-Siberian species that has extended the southern border of its habitat and has been distributed in the south of Kazakhstan and in the north of Kyrgyzstan. In, Kyrgyzstan, An. messeae inhabiting the plains of Europe and Siberia is encountered rather high up in the mountains: the highest point where this species is found is at 1,879 m above sea level. An. artemievi is present in the highland and piedmont regions of Central Asia (Uzbekistan, Kyrgyzstan, southern Kazakhstan, and northern Tajikistan) and in the intermountain basins (Naryn and Fergana ones). The single finding of this species is in south-eastern Turkmenistan. On the contrary, An. martinius tends to be in the plains and occurs in north-eastern Turkmenistan, Karakalpakstan, and Kazakhstan (Kzyl-Orda). On the other hand, a population of this species is found in proximity to the foothills of the Gissar Range in the east of Uzbekistan. An.maculipennis s.str. is not seen in Central Asia. Early evidence for the presence of both An. maculipennis s.str. and An. martinius in Kopet Dag (Southern Turkmenistan) is rather questionable. It is not improbable that these data are appropriate for either the newly described species An.persiensis or the scientifically new representative of the An. maculipennis complex.

[Chromosomal polymorphism in the populations of malaria mosquito Anopheles messeae (Diptera, Culicidae) at the south of Russian Plain].

Zonal features of the geographic distribution of chromosomal inversions in the populations of An. messae at the south of the Russian Plain were examined. The An. messae was identified based on morphological characters and cytogenetically. The chromosomal inversions identified in populations of An. messae comprised XL1, XL4, 2R1, 3R1, and 3L1. Inversion XL4 was endemic and found with low frequency (2%) in Penza oblast and Moscow oblast. Based on the population karyotype structure similarity, on the territory of Russian Plain, three zones (southwestern, southeastern, and central) were identified. Central zone was characterized by higher levels of inversion polymorphism in all chromosomes, except arm 3L. In the two southern zones, high frequency of the XL0 inversion, along with complete absence of homo- and heterozygotes for the 2R1 inversion, and high proportion of the individuals with inversion 3L1 was observed. Specific feature of southeastern zone was the increased frequency ofhetero- and homozygotes for the 3R1 and 3L1 inversions. Zonal differences reflected adaptive character ofchromosomal polymorphism and pointed to hierarchic organization of the species population structure.

[Malaria mosquitoes (Diptera, Culicidae, Anopheles) of North Tajikistan, their ecology, and role in the transmission of malaria pathogens].

Five species of malaria mosquitoes: An. artemievi, An. claviger, An. hyrcanus, An. superpictus, and An. pulcherrimus were found in North Tajikistan in 2006 - 2007. Species affiliation was identified according to the morphological signs of their larvae and imagoes, and by using the polymerase chain reaction-restriction fragment length polymorphism analysis. There was a larger number of An. hyrcanus (34%), An. artemievi (29%), and An. pulcherrimus (24%) and a smaller number of An. superpictus (11%); and An. claviger was few (2%). The hatching sites of the above species and the preferred types of their day refuges were found. The intensity of attack of different Anopheles species on humans and animals was studied. Among the North Tajikistan malaria mosquitoes, An. pulcherrimus and An. superpictus are of the greatest epidemiological importance as vehicles for transmission of malaria pathogens. An. artemievi and An. hyrcanus are minor vehicles. At present, An. claviger is of no epidemiological significance in transmitting malaria in North Tajikistan.

[Inversion polymorphism and ecological specialization of malaria mosquitoes (Diptera, Culicidae) in Karelia].

The species composition and inversion polymorphism were studied in malaria mosquito larva hemipopulations of Karelia. Three malaria mosquito species--Anopheles messeae, A. beklemishevi, and A. maculipennis--were found in the region. The northern boundary of their range is at 65 degrees NL. The greatest species diversity was observed in biotopes of the central region. Within-species chromosome polymorphism was observed in larva populations of all three species. For A. messeae, maximum karyotype diversity indices were established for the southern and northern regions of Karelia.

[The population-and-species-specific structure of malaria (Diptera, Culicidae) mosquitoes in the Caspian Lowland and Kuma-Manych Hollow].

The authors studied the population-and-species-specific structure of malaria mosquitoes in the Caspian Lowland and Kuma-Manych Hollow (Republic of Kalmykia, Stavropol Territory). Five Anopheles mosquito species were identified. An. messeae and An. atroparvus were dominant; An. maculipennis, An. hyrcanus, and An. sacharovi were ecologically specialized and relatively rare. An. sacharovi was first found in Kalmykia, which is the most dangerous malaria vector in the south regions of the CIS. This allows the former known borders of its area to be expanded to the northwest Paleartics. An. messeae showed a high rate of inversions along both arms of chromosome 3 in homo- and heterozygous states, as well as a unique inversion in sex chromosome. The An. atroparvus population in the region was found to have a high rate of inversion on the 3L arm, which had been previously recognized as rare in Ukraine only.

[PCR-RFLP and sequencing studies of malaria vectors (Diptera, Culicidae, Anopheles) in Kyrgyzstan].

The results of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, obtained after treatment of PCR-products with restriction endonuclease CfoI, could identify two members of the Anopheles maculipennis complex: An. maculipennis and An. artemievi. Treatment of amplification products with restriction endonuclease BsuI gave rise to fragment lengths of 192 and 218 bp, characteristic of An. artemievi, in the populations of the Talas (settlement of Kizil-Adyr, Kara-Bura District), Dzhelalabad (towns of Tashkumyr and Kara-Kul), and Osh (town of Gulcha, Alai District; village of Langar, Kara-Suisky District) Regions. After treatment of PCR-products with restriction endonuclease BstACI, fragment lengths of 292 and 150 bp, characteristic of An. messeae, were obtained for the mosquitoes of Issyk-Kul (town of Balykchi) and Naryn (settlement of Kochkorka, Kochkor District) Regions. To identify the molecular forms of An. superpictus, the investigators sequenced the amplification products obtained by PCR with 5.8S and 28S rRNA gene-specific primers. Analysis of the primary structure of the second internal transcribed spacer, by using the international databases, has indicated that molecular form X is prevalent in the study districts of Kyrgyzstan. The COI-COII region of the mitochondrial genome of the vector also underwent PCR-RFLP analysis. Three new haplotypes with restriction patterns of about 540, 420, 200, 150, 140 bp, about 540, 360, 280, 150, 140 bp, and about 580, 540, and 150, 140 bp have been identified along with the previously described haplotype X characterized by restriction products of 540, 420, 260, 150, and 140 bp in length.

[Detection of Anopheles artemievi Gordeev et al. (Diptera, Culicidae) in Turkmenistan].

Anopheles artemievi (a member of An. maculipennis complex species) described from the Transfergana region (South Kyrgyzstan) in 2004 was first found in the Lebap veloyat (Eastern Turkmenistan). A single larva of this species was collected together with An. superpictus in the irrigation channel of a rice field. Species affiliation has been proven by a polymerase chain reaction-restriction fragment length polymorphism method. This species is to be included into a list of Anopheles species of Turkmenistan.

[The population-and-species-specific structure of anopheles (diptera, culicidae) mosquitoes in the Upper Rhine Valley, Germany].

The authors studied the population-and-species-specific structure of malaria mosquitoes in the Upper Rhine valley, Germany. Four Anopheles mosquito species were identified. These included An. claviger, An. maculipennis, An. messeae, and An. plumbeus. The predominance coefficients of the species were determined. An. messeae is dominant; An. maculipennis is subdominant, An. plumbeus and An. claviger are rare. The latter two species are ecologically specialized and predominantly develop inthe biotopes that are inaccessible for dominant species. The karyotypes of An. messeae show a high variability in sex chromosome XL and a low rate of homo- and heterozygotes in 3R, inversion. The greatest species-specific and karyotypic variety of malaria mosquitoes is noted for large aquatic biotopes.

[Study of the pathogen populations of tertian malaria and possibilities of its establishment in Kyrgyzstan].

A genetic analysis has indicated that the population of the tertian malaria causative agents Plasmodium vivax in Kyrgyzstan is heterogeneous and consists of various isolates resulting from multiple carriages of the pathogens from the areas of the neighboring countries. Low genetic variability and a weak gene flow between the isolates do not contribute to the establishment of malaria in this area. Experience in controlling the epidemic outbreaks shows that active and residual foci are easily sanitized when antimalaria measures are timely and qualitatively implemented. This creates the necessary for eliminating tertian malaria in the Republic of Kyrgyzstan in the near future.

[Molecular genetic analysis of malaria mosquitoes of the Anopheles maculipennis (Diptera, Culicidae) complex in Azerbaijan].

Molecular genetic analysis of malaria vectors in the Republic of Azerbaijan has identified three species of malaria mosquitoes of the Anopheles maculipennis complex: An. maculipennis, An. sacharovi, and An. persiensis. An. melanoon has not been found. An. sacharovi has been ascertained to predominate in the low-lying areas of the country. An. maculipennis prevails in the north, on the foothills of the Great Caucasus and it is also observed in the south, on the Talysh foothills and mountains. An. persiensis has been first recorded for the malaria mosquito fauna in the CNS. This species has been detected only in the south of the republic (Lenkoran and Astar districts).

[Genetic analysis of malaria mosquitoes of Anopheles maculipennis (Diptera, Culicidae) complex from Armenia].

The results of morphological, cytogenetic, and molecular genetic analyses of malaria mosquitoes from Armenia have indicated that two representatives of the maculipennis complex, such as An. maculipennis s.s. and An. sacharovi, inhabit in the blotopes under study. The predominant species is An. maculipennis that is present in all the examined habitats. This species accounts for 15.5% of all the mosquitoes of the maculipennis complex. An. sacharovi has been found only in the Ararat valley where its proportion varies from 25 to 91.7%. Morphological, cytogenetic, and molecular genetic criteria are shown to be used to determine the warrior species of the maculipennis complex in Armenia.

[Chromosome polymorphism and regularities of the subpopulation organization of malaria mosquitoes Anopheles (Diptera, Culicidae) in biotopes of the Tomsk oblast].

A biotopic subdivision was observed for the two closely related species Anopheles messeae and A. beklemishevi in larval biotopes of the Tomsk oblast. The regularities of the spatial distribution of A. messeae with various chromosomal inversions were determined. The A. messeae karyotypic structure proved to vary depending on the ecological conditions of wintering and reproduction sites. The frequencies of chromosome variants XL0, 2R0, 3R0, and 3L0 were maximal in villages, while forest biotopes were characterized by elevated frequencies of alternative inversions. A comparison of the chromosomal structure for larvae and adults confirmed the subdivision of spatial niches for adults with different karyotypes. The difference in spatial niches was assumed to reflect the ecological specialization of mosquitoes. At the interspecific level, such specialization allows closely related species to occur in sympatry regions. At the intraspecific level, a subdivision of spatial niches reduces the intraspecific competition, increases the population size, and improves the survival during unfavorable periods associated with changes in abiotic factors.

[Anopheles mosquitoes (Diptera, Culicidae) of the Tien Shan: morphological, cytogenetic, and molecular genetic analysis].

Morphological, cytogenetic, and molecular genetic studies of the Anopheles fauna in the valley and foothills of the Tien Shan identified 5 species of malaria mosquitoes: An. artemievi Gordeev et al., An. messeae Fall, An. claviger Meigen, An. hyrcanus Pallas, An. pulcherrimus Theobald, and superpictus Grassi. An. claviger, An. hyrcanus, and An. messeae were prevalent in the Northern Tien-Shan. An. artemievi, An. claviger, An. hyrcanus, An. messeae, and An. superpictus were detected in the Western Tien Shan. An. artemievi was first recorded in Kazakhstan. An. artemievi, An. claviger, and An. superpictus were noted in the Inferior Tien Shan. An. messeae was first observed in the Issyk Kul hollow. An. artemievi, An. claviger, and An. superpictus were habitants of the foothills of the South-Western Tien Shan. An. artemievi, An. hyrcanus, An. superpictus, and An. pulcherrimus were in the plain. An. pulcherrimus and An. superpicts mosquitoes are regarded as important vectors in the new malaria foci of the Fergana regions. The role of An. artemievi in the transmission of malaria is to be specified.

[Malaria mosquitoes of the Anopheles maculipennis (Diptera, Culicidae) complex in Georgia].

Malaria mosquito larvae and imagoes underwent morphological, cytogenetic, and molecular genetic analyses in West and East Georgia. In the areas under study, the authors identified three related types of malaria mosquitoes of the maculipennis complex: An. maculipennis Meigen, 1818; An. melanoon Hacket, 1934; An. sacharovi Favre, 1903. The authors revealed the types An. maculipennis and An. melanoon in the Kolkhida cavity (West Georgia) and An. maculipennis and An. sacharovi in the Iveria cavity (East Georgia). The morphology of eggs was defined in the study types of mosquitoes. An. melanoon ovipositions similar in the exochorion pattern with An. messeae eggs were found in West Georgia.