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Soto-Garita, C.

Publications and source records attributed to Soto-Garita, C..

3 recordsLinked to original sources

Overview of the SARS-CoV-2 genotypes circulating in Latin America during 2021

Latin America is one of the regions in which the COVID-19 pandemic has had a stronger impact, with more than 72 million reported infections and 1.6 million deaths until June 2022. Since this region is ecologically diverse and is affected by enormous social inequalities, efforts to identify genomic patterns of the circulating SARS-CoV-2 genotypes are necessary for the suitable management of the pandemic. To contribute to the genomic surveillance of the SARS-CoV-2 in Latin America, we extended the number of SARS-CoV-2 genomes available from the region by sequencing and analyzing the viral genome from COVID-19 patients from seven countries (Argentina, Brazil, Costa Rica, Colombia, Mexico, Bolivia and Peru). Subsequently, we analyzed the genomes circulating mainly during 2021 including records from GISAID database from Latin America. A total of 1534 genome sequences were generated from seven countries, demonstrating the laboratory and bioinformatics capabilities for genomic surveillance of pathogens that have been developed locally. For Latin America, patterns regarding several variants associated with multiple re-introductions, a relatively low percentage of sequenced samples, as well as an increment in the mutation frequency since the beginning of the pandemic, are in line with worldwide data. Besides, some variants of concern (VOC) and variants of interest (VOI) such as Gamma, Mu and Lambda, and at least 83 other lineages have predominated locally with a country-specific enrichments. This work has contributed to the understanding of the dynamics of the pandemic in Latin America as part of the local and international efforts to achieve timely genomic surveillance of SARS-CoV-2.

microbiology↗

Experimental infection of Artibeus lituratus bats and no detection of Zika virus in neotropical bats from French Guyana, Peru, and Costa Rica, suggest a limited role of bats in Zika transmission.

Bats are important natural reservoir hosts of a diverse range of viruses that can be transmitted to humans and have been suggested that could play an important role in the Zika virus (ZIKV) transmission cycle. However, the exact role of these animals as reservoirs for Flaviviruses is still controversial. To further expand our understanding of the role of bats in the ZIKV transmission cycle in Latin America, we carried an experimental infection in wild-caught Artibeus bats and sampled several free-living neotropical bats over three countries of the region. Experimental ZIKV infection was made in free-ranging adult bats (4 females and 5 males). The most relevant gross findings were hemorrhages in the bladder, stomach and patagium. Significant histological findings included inflammatory infiltrate consisting of a predominance of neutrophils and lymphocytes, in addition to degeneration in the reproductive tract of males and females. This suggests that bat reproduction might be at some level affected by ZIKV. Leukopenia was also observed in some inoculated animals. Hemorrhages, genital alterations, and leukopenia are suggestive to be caused by ZIKV, however, since these are wild-caught bats, we can not exclude other agents. Excretion of ZIKV by qPCR was detected (low titles) in only two urine samples in two inoculated animals. All other animals and tissues tested negative. Finally, no virus-neutralizing Abs were found in any animal. To determine ZIKV infection in nature, a total of 2056 bats were blood sampled for ZIKV detection by qPCR. Most of the sampled individuals belonged to the genus Pteronotus sp. (23%), followed by the species Carollia sp. (17%); Anoura sp. (14%), and Molossus sp. (13.7 %). No sample of any tested species resulted positive to ZIKV by qPCR. These results together suggest that bats are not efficient amplifiers or reservoirs of ZIKV and may not have an important role in ZIKV transmission dynamics. Author summaryIn previous works made in 2008-2009, we have found the presence of antibodies against Flaviviruses and viral RNA has been detected in Neotropical chiropterans of Mexico, which led us to support the hypothesis that these animals could be reservoirs of Flaviviruses. As controversial opinions have been exposed, and based on a previous (2019) experimental ZIKV infection made in Colorado State University using adult Artibeus males from a captive colony, in this work we also experimentally infected adult Artibeus males complementarily adding females and using free-living animals instead of laboratory bats. We also monitored a diverse range of natural bat populations in Latin America for the presence of viral RNA against ZIKV in blood. A plaque reduction seroneutralization test was used for the detection of antibodies against ZIKV. Similar to the previous work, we found histopathological alteration in male testicles but also in ovaries and oviducts of females, as well as gliosis and multifocal necrosis in pyramidal neurons and Purkinge cells of inoculated animals. Only two urine samples from inoculated animals showed viral RNA. Additionally, leukopenia and lymphoid follicular splenic hyperplasia were evidenced. Differing to what was reported, no neutralizing antibodies against ZIKV were detected in any sample. Viral RNA within the blood was not present in any of the 2056 bat samples collected in French Guyana, Peru and Costa Rica and proceeding from 33 bat genera. These results together suggest that bats are not efficient amplifiers or reservoirs of ZIKV and might not have an important role on ZIKV transmission dynamics.

microbiology↗

SARS-CoV-2 Genomic Surveillance in Costa Rica: Evidence of a Divergent Population and an Increased Detection of a Spike T1117I Mutation

Genome sequencing is a key strategy in the surveillance of SARS-CoV-2, the virus responsible for the COVID-19 pandemic. Latin America is the hardest hit region of the world, accumulating almost 20% of COVID-19 cases worldwide. Costa Rica was first exemplary for the region in its pandemic control, declaring a swift state of emergency on March 16th that led to a low quantity of cases, until measures were lifted in early May. From the first detected case in March 6th to December 31st almost 170 000 cases have been reported in Costa Rica, 99.5% of them from May onwards. We analyzed the genomic variability during the SARS-CoV-2 pandemic in Costa Rica using 185 sequences, 52 from the first months of the pandemic, and 133 from the current wave. Three GISAID clades (G, GH, and GR) and three PANGOLIN lineages (B.1, B.1.1, and B.1.291) are predominant, with phylogenetic relationships that are in line with the results of other Latin American countries, suggesting introduction and multiple re-introductions from other regions of the world. The whole-genome variant calling analysis identified a total of 283 distinct nucleotide variants. These correspond mostly to non-synonymous mutations (51.6%, 146) but 45.6% (129) corresponded to synonymous mutations. The 283 variants showed an expected power-law distribution: 190 single nucleotide mutations were identified in single sequences, only 16 single nucleotide mutations were found in >5% sequences, and only two mutations in >50% genomes. These mutations were distributed through the whole genome. However, 63.6% were present in ORF1ab, 11.7% in Spike gene and 10.6% in the Nucleocapsid gene. Additionally, the prevalence of worldwide-found variant D614G in the Spike (98.9% in Costa Rica), ORF8 L84S (1.1%) is similar to what is found elsewhere. Interestingly, the frequency of mutation T1117I in the Spike has increased during the current pandemic wave beginning in May 2020 in Costa Rica, reaching 29.2% detection in the full genome analyses in November 2020. This variant has been observed in less than 1% of the GISAID reported sequences worldwide in all the 2020. Structural modeling of the Spike protein with the T1117I mutation suggest a potential effect on the viral oligomerization needed for cell infection, but no differences with other genomes on transmissibility, severity nor vaccine effectiveness are predicted. Nevertheless, in-vitro experiments are required to support these in-silico findings. In conclusion, genome analyses of the SARS-CoV-2 sequences over the course of COVID-19 pandemic in Costa Rica suggest introduction of lineages from other countries as travel bans and measures were lifted, similar to results found in other studies, as well as an increase in the Spike-T1117I variant that needs to be monitored and studied in further analyses as part of the surveillance program during the pandemic.

genomics↗