Molecular Characterization of Leishmania RNA virus 2 in Leishmaniamajor from Uzbekistan.

Here we report sequence and phylogenetic analysis of two new isolates of Leishmania RNA virus 2 (LRV2) found in Leishmania major isolated from human patients with cutaneous leishmaniasis in south Uzbekistan. These new virus-infected flagellates were isolated in the same region of Uzbekistan and the viral sequences differed by only nineteen SNPs, all except one being silent mutations. Therefore, we concluded that they belong to a single LRV2 species. New viruses are closely related to the LRV2-Lmj-ASKH documented in Turkmenistan in 1995, which is congruent with their shared host (L. major) and common geographical origin.

A narrative review of visceral leishmaniasis in Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, the Crimean Peninsula and Southern Russia.

There is an extensive body of medical and scientific research literature on visceral leishmaniasis (VL) in the Caucasus, Central Asia, the Crimean Peninsula and the southern part of The Russian Federation that is written in Russian, making it inaccessible to the majority of people who are interested in the leishmaniases in general and VL in particular. This review and summary in English of VL in what was Imperial Russia, which then became the Soviet Union and later a number of different independent states intends to give access to that majority. There are numerous publications in Russian on VL and, mostly, those published in books and the main scientific journals have been included here. The vast geographical area encompassed has been subdivided into four main parts: the southern Caucasus, covering Armenia, Azerbaijan and Georgia; Central Asia, covering Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan; the Crimean Peninsula and the northern Caucasus, which is part of The Russian Federation. Only rare cases of VL have been recorded in the northern Caucasus and Crimean Peninsula. In the other countries mentioned, human VL has been more intense but epidemics like those associated with L. donovani in India and East Africa have not occurred. For most of the countries, there are sections on the distribution, clinical aspects, the causative agent, the reservoirs and the vectors. Serological surveys and research into therapy are also covered. Recent studies on VL in Uzbekistan covered the application of serological, biochemical and molecular biological methods to diagnose human and canine VL, to identify the leishmanial parasites causing them in Uzbekistan and neighbouring Tajikistan and the epidemiology of VL in the Namangan Region of the Pap District, Eastern Uzbekistan. More recently, two studies were carried out in Georgia investigating the prevalence of human and canine VL, and the species composition of phlebotomine sand flies and their rates of infection with what was probably L. infantum in Tbilisi, eastern Georgia and Kutaisi, a new focus, in western Georgia. Though published in English, summaries of this information have been included where relevant to update the parts on VL in Uzbekistan and Georgia.

Canine leishmaniosis and its relationship to human visceral leishmaniasis in Eastern Uzbekistan.

BACKGROUND: The Namangan Region in the Pap District, located in Eastern Uzbekistan is the main focus of visceral leishmaniasis (VL) in Uzbekistan. In total, 28 cases of human VL were registered during 2006-2008 in this region. A study on the epidemiology of VL in this area was carried out in 2007-2008 in the villages of Chodak, Oltinkan, Gulistan and Chorkesar located at elevations of 900-1200 above sea level. RESULTS: A total of 162 dogs were tested for Leishmania infection. Blood was drawn for serology and PCR. When clinical signs of the disease were present, aspirates from lymph nodes and the spleen were taken. Forty-two dogs (25.9%) had clinical signs suggestive of VL and 51 (31.5%) were sero-positive. ITS-1 PCR was performed for 135 dogs using blood and tissue samples and 40 (29.6%) of them were PCR-positive. Leishmanial parasites were cultured from lymph node or spleen aspirates from 10 dogs.Eight Leishmania strains isolated from dogs were typed by multi-locus microsatellite typing (MLMT) and by multilocus enzyme electrophoretic analysis (MLEE), using a 15 enzyme system. These analyses revealed that the strains belong to the most common zymodeme of L. infantum, i.e., MON-1, and form a unique group when compared to MON-1 strains from other geographical regions. CONCLUSIONS: The data obtained through this study confirm the existence of an active focus of VL in the Namangan region of Uzbekistan. The fact that L. infantum was the causative agent of canine infection with typical clinical signs, and also of human infection affecting only infants, suggests that a zoonotic form of VL similar in epidemiology to Mediterranean VL is present in Uzbekistan.

Selective amplification of maxicircle classes during the life cycle of Leishmania major.

The kinetoplast genome contains several thousands of minicircles of various sequence classes and several scores of maxicircles. We demonstrated that maxicircles are heterogeneous in clonal cultures of Leishmania major, and, therefore, probably heterogeneous (heteroplasmic) within the kinetoplast. Sequence heterogeneity was observed in a non-coding fragment upstream of the 12S rRNA gene. We identified about 20 stable variants of this fragment, which were composed of one to five non-identical repeats 200-300bp in length. Promastigote-to-amastigote and amastigote-to-promastigote differentiation was often accompanied by shifts in abundance of some maxicircle classes. Reversion to promastigote-specific maxicircle patterns was usually observed in the life cycle (promastigote-amastigote-promastigote), however there were many exceptions.