Nejvíce citovaný článek - PubMed ID 36453145
Revisiting epidemiology of leishmaniasis in central Asia: lessons learnt
In Uzbekistan, the number of reported leishmaniasis cases is rising at the alarming rate. In this work, we studied the phlebotomine sand fly (Diptera: Phlebotominae) diversity in the foci of cutaneous leishmaniasis in the Surxondaryo Region of Uzbekistan and compared it with the data obtained for the same area 50 years ago, when infection prevalence was reportedly low. We found that the implicated vector for zoonotic leishmaniasis, P. papatasi, remained eudominant; the proportion of implicated anthroponotic leishmaniasis vector, P. sergenti, rose significantly from averaged 5.4 to 41.4%; Phlebotomus alexandri, a suspected visceral leishmaniasis vector, was eudominant at two sites, and a second suspected vector for this disease, P. longiductus, was newly recorded in the region. We conclude that the increase in the documented cases of cutaneous leishmaniasis in the Surxondaryo Region of Uzbekistan may be connected to the changes in fauna of sand flies vectoring Leishmania spp.
- Klíčová slova
- Diversity, Leishmania, Phlebotomus,
- MeSH
- hmyz - vektory MeSH
- leishmanióza kožní * epidemiologie MeSH
- leishmanióza viscerální * epidemiologie MeSH
- Phlebotomus * MeSH
- Psychodidae * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Uzbekistán epidemiologie MeSH
RNA viruses play an important role in Leishmania biology and virulence. Their presence was documented in three (out of four) Leishmania subgenera. Sauroleishmania of reptiles remained the only underinvestigated group. In this work, we analyzed the viral occurrence in Sauroleishmania spp. and detected RNA viruses in three out of seven isolates under study. These viruses were of two families-Narnaviridae and Totiviridae. Phylogenetic inferences demonstrated that totiviruses from L. adleri and L. tarentolae group together within a larger cluster of LRV2s, while a narnavirus of L. gymnodactyli appeared as a phylogenetic relative of narnaviruses of Blechomonas spp. Taken together, our work not only expanded the range of trypanosomatids that can host RNA viruses but also shed new light on the evolution and potential routes of viral transmission in these flagellates.
- Klíčová slova
- L. (S.) gymnodactyli, L. (S.) hoogstraali, L. (S.) tarentolae, LRV2, Leishmania (Sauroleishmania) adleri, Narnaviridae,
- MeSH
- fylogeneze MeSH
- Leishmania * MeSH
- lidé MeSH
- plazi MeSH
- RNA-viry * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Leishmania RNA virus 1 (LRV1) is commonly found in South American Leishmania parasites belonging to the subgenus Viannia, whereas Leishmania RNA virus 2 (LRV2) was previously thought to be restricted to the Old-World pathogens of the subgenus Leishmania. OBJECTIVES: In this study, we investigated the presence of LRV2 in strains of Leishmania (L.) infantum, the causative agent of visceral leishmaniasis (VL), originating from different hosts, clinical forms, and geographical regions. METHODS: A total of seventy-one isolates were screened for LRV2 using semi-nested reverse transcription-polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase (RdRp) gene. FINDINGS: We detected LRV2 in two L. infantum isolates (CUR268 and HP-EMO) from canine and human cases, respectively. MAIN CONCLUSIONS: To the best of our knowledge, this is the first detection of LRV2 in the New World.
- MeSH
- Leishmania infantum * genetika MeSH
- leishmanióza viscerální * veterinární MeSH
- lidé MeSH
- psi MeSH
- RNA-dependentní RNA-polymerasa MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Brazílie MeSH
- Názvy látek
- RNA-dependentní RNA-polymerasa MeSH
Leishmaniases are neglected diseases caused by protozoans of the genus Leishmania that threaten millions of people worldwide. Cutaneous leishmaniasis (CL) caused by L. major is a typical zoonosis transmitted by phlebotomine sand flies and maintained in rodent reservoirs. The female sand fly was assumed to become infected by feeding on the skin lesion of the host, and the relative contribution of asymptomatic individuals to disease transmission was unknown. In this study, we infected 32 Meriones shawi, North African reservoirs, with a natural dose of L. major obtained from the gut of infected sand flies. Skin manifestations appeared in 90% of the animals, and xenodiagnosis with the proven vector Phlebotomus papatasi showed transmissibility in 67% of the rodents, and 45% were repeatedly infectious to sand flies. Notably, the analysis of 113 xenodiagnostic trials with 2189 sand flies showed no significant difference in the transmissibility of animals in the asymptomatic and symptomatic periods; asymptomatic animals were infectious several weeks before the appearance of skin lesions and several months after their healing. These results clearly confirm that skin lesions are not a prerequisite for vector infection in CL and that asymptomatic animals are an essential source of L. major infection. These data are important for modeling the epidemiology of CL caused by L. major.
- Klíčová slova
- Leishmania, Meriones, Phlebotomus, asymptomatic infection, reservoir host, xenodiagnosis,
- Publikační typ
- časopisecké články MeSH
The evolution in Leishmania is governed by the opposite forces of clonality and sexual reproduction, with vicariance being an important factor. As such, Leishmania spp. populations may be monospecific or mixed. Leishmania turanica in Central Asia is a good model to compare these two types. In most areas, populations of L. turanica are mixed with L. gerbilli and L. major. Notably, co-infection with L. turanica in great gerbils helps L. major to withstand a break in the transmission cycle. Conversely, the populations of L. turanica in Mongolia are monospecific and geographically isolated. In this work, we compare genomes of several well-characterized strains of L. turanica originated from monospecific and mixed populations in Central Asia in order to shed light on genetic factors, which may drive evolution of these parasites in different settings. Our results illustrate that evolutionary differences between mixed and monospecific populations of L. turanica are not dramatic. On the level of large-scale genomic rearrangements, we confirmed that different genomic loci and different types of rearrangements may differentiate strains originated from mixed and monospecific populations, with genome translocations being the most prominent example. Our data suggests that L. turanica has a significantly higher level of chromosomal copy number variation between the strains compared to its sister species L. major with only one supernumerary chromosome. This suggests that L. turanica (in contrast to L. major) is in the active phase of evolutionary adaptation.
- MeSH
- genomika MeSH
- Gerbillinae parazitologie MeSH
- Leishmania * genetika MeSH
- variabilita počtu kopií segmentů DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Mongolsko MeSH