Untranslated Regions of a Segmented Kindia Tick Virus Genome Are Highly Conserved and Contain Multiple Regulatory Elements for Viral Replication.

Novel segmented tick-borne RNA viruses belonging to the group of Jingmenviruses (JMVs) are widespread across Africa, Asia, Europe, and America. In this work, we obtained whole-genome sequences of two Kindia tick virus (KITV) isolates and performed modeling and the functional annotation of the secondary structure of 5' and 3' UTRs from JMV and KITV viruses. UTRs of various KITV segments are characterized by the following points: (1) the polyadenylated 3' UTR; (2) 5' DAR and 3' DAR motifs; (3) a highly conserved 5'-CACAG-3' pentanucleotide; (4) a binding site of the La protein; (5) multiple UAG sites providing interactions with the MSI1 protein; (6) three homologous sequences in the 5' UTR and 3' UTR of segment 2; (7) the segment 2 3' UTR of a KITV/2017/1 isolate, which comprises two consecutive 40 nucleotide repeats forming a Y-3 structure; (8) a 35-nucleotide deletion in the second repeat of the segment 2 3' UTR of KITV/2018/1 and KITV/2018/2 isolates, leading to a modification of the Y-3 structure; (9) two pseudoknots in the segment 2 3' UTR; (10) the 5' UTR and 3' UTR being represented by patterns of conserved motifs; (11) the 5'-CAAGUG-3' sequence occurring in early UTR hairpins. Thus, we identified regulatory elements in the UTRs of KITV, which are characteristic of orthoflaviviruses. This suggests that they hold functional significance for the replication of JMVs and the evolutionary similarity between orthoflaviviruses and segmented flavi-like viruses.

The Viromes of Mosquitoes from the Natural Landscapes of Western Siberia.

The metagenomic analysis of mosquitoes allows for the genetic characterization of mosquito-associated viruses in different regions of the world. This study applied a metagenomic approach to identify novel viral sequences in seven species of mosquitoes collected from the Novosibirsk region of western Siberia. Using NGS sequencing, we identified 15 coding-complete viral polyproteins (genomes) and 15 viral-like partial sequences in mosquitoes. The complete sequences for novel viruses or the partial sequences of capsid proteins, hypothetical viral proteins, and RdRps were used to identify their taxonomy. The novel viral sequences were classified within the orders Tymovirales and Picornavirales and the families Partitiviridae, Totiviridae, Tombusviridae, Iflaviridae, Nodaviridae, Permutotetraviridae, and Solemoviridae, with several attributed to four unclassified RNA viruses. Interestingly, the novel putative viruses and viral sequences were mainly associated with the mosquito Coquillettidia richardii. This study aimed to increase our understanding of the viral diversity in mosquitoes found in the natural habitats of Siberia, which is characterized by very long, snowy, and cold winters.

The First Case of Zika Virus Disease in Guinea: Description, Virus Isolation, Sequencing, and Seroprevalence in Local Population.

The Zika virus (ZIKV) is a widespread mosquito-borne pathogen. Phylogenetically, two lineages of ZIKV are distinguished: African and Asian-American. The latter became the cause of the 2015-2016 pandemic, with severe consequences for newborns. In West African countries, the African lineage was found, but there is evidence of the emergence of the Asian-American lineage in Cape Verde and Angola. This highlights the need to not only monitor ZIKV but also sequence the isolates. In this article, we present a case report of Zika fever in a pregnant woman from Guinea identified in 2018. Viral RNA was detected through qRT-PCR in a serum sample. In addition, the seroconversion of anti-Zika IgM and IgG antibodies was detected in repeated blood samples. Subsequently, the virus was isolated from the C6/36 cell line. The detected ZIKV belonged to the African lineage, the Nigerian sublineage. The strains with the closest sequences were isolated from mosquitoes in Senegal in 2011 and 2015. In addition, we conducted the serological screening of 116 blood samples collected from patients presenting to the hospital of Faranah with fevers during the period 2018-2021. As a result, it was found that IgM-positive patients were identified each year and that the seroprevalence varied between 5.6% and 17.1%.

Ngari virus (Orthobunyavirus, Peribunyaviridae) in ixodid ticks collected from cattle in Guinea.

Ngari virus is a mosquito-borne virus belonging to the genus Orthobunyavirus (Peribunyaviridae family). This virus is pathogenic to humans and causes severe illness. Ngari virus is present in several African countries, including Madagascar. Here, we report the detection of Ngari virus in ixodid ticks collected from cows in Guinea. A tick survey was conducted in March-November of 2018 in six regions of Guinea. The sample comprised 710 pools, with a total of 2067 ticks belonging to five species collected from 197 cows. At the initial stage, we screened a subsample of tick pools of vector-borne viruses with a multiplex genus-specific primer panel. In the second stage of the study, we narrowed the search and screened all the samples by qPCR for the detection of Ngari virus. All positive samples were sequenced with primers flanking Ngari virus-specific fragments on the S and M segments. We found Ngari virus in 12 pools that were formed from engorged ticks collected from livestock in three villages of the Kindia and Kankan regions. Sequencing of the S and M segments confirmed that the detected viruses belong to Ngari virus, and the viruses were most similar to the strain Adrar, which was isolated in Mauritania. We detected viral RNA in ticks of the following species: Amblyomma variegatum, Rhipicephalus geigyi, and Rh. (Boophilus) spp. There is no evidence that ixodid ticks are competent vectors of the Ngari virus. Most likely, the ticks obtained the virus through blood from an infected host. The study of engorged ticks can be recommended as a simpler approach for the wide screening of the Ngari virus and subsequent testing of cattle and mosquitos in those locations where the PCR-positive ticks were collected.

Bombali Virus in Mops condylurus Bats, Guinea.

In 2018, a previously unknown Ebola virus, Bombali virus, was discovered in Sierra Leone. We describe detection of Bombali virus in Guinea. We found viral RNA in internal organs of 3 Angolan free-tailed bats (Mops condylurus) trapped in the city of N'Zerekore and in a nearby village.