Sputnik V-Induced Antibodies against SARS-CoV-2 Variants during the Dissemination of the Gamma Variant in Venezuela.

The COVID-19 pandemic was characterized by the emergence and succession of SARS-CoV-2 variants able to evade the antibody response induced by natural infection and vaccination. To evaluate the IgG reactivity and neutralizing capacity of the serum of individuals vaccinated with Sputnik V (105 volunteers vaccinated) against different viral variants. IgG reactivity to the Spike protein (S) was evaluated by ELISA.

Humoral Immunity across the SARS-CoV-2 Spike after Sputnik V (Gam-COVID-Vac) Vaccination.

SARS-CoV-2 vaccines have contributed to attenuating the burden of the COVID-19 pandemic by promoting the development of effective immune responses, thus reducing the spread and severity of the pandemic. A clinical trial with the Sputnik-V vaccine was conducted in Venezuela from December 2020 to July 2021. The aim of this study was to explore the antibody reactivity of vaccinated individuals towards different regions of the spike protein (S).

Description of a One-Year Succession of Variants of Interest and Concern of SARS-CoV-2 in Venezuela.

Some of the lineages of SARS-CoV-2, the new coronavirus responsible for COVID-19, exhibit higher transmissibility or partial resistance to antibody-mediated neutralization and were designated by WHO as Variants of Interests (VOIs) or Concern (VOCs). The aim of this study was to monitor the dissemination of VOIs and VOCs in Venezuela from March 2021 to February 2022. A 614 nt genomic fragment was sequenced for the detection of some relevant mutations of these variants.

Introduction and rapid dissemination of SARS-CoV-2 Gamma Variant of Concern in Venezuela.

In less than two years since SARS-CoV-2 emerged, the new coronavirus responsible for COVID-19, has accumulated a great number of mutations. Many of these mutations are located in the Spike protein and some of them confer to the virus higher transmissibility or partial resistance to antibody mediated neutralization. Viral variants with such confirmed abilities are designated by WHO as Variants of Concern (VOCs).

SARS-CoV-2 genetic diversity in Venezuela: Predominance of D614G variants and analysis of one outbreak.

SARS-CoV-2 is the new coronavirus responsible for COVID-19 disease. The first two cases of COVID-19 were detected in Venezuela on March 13, 2020. The aim of this study was the genetic characterization of Venezuelan SARS-CoV-2 isolates.

The Evolving HIV-1 Epidemic in Warao Amerindians Is Dominated by an Extremely High Frequency of CXCR4-Utilizing Strains.

We previously reported a high prevalence of HIV-1 infection in Warao Amerindians from Venezuela due to the rapid spread of a single B subtype strain. In this study we evaluated the coreceptor use of the HIV-1 strains infecting this Amerindian community. Sequences of the HIV-1 V3 loop from 56 plasma samples were genotyped for coreceptor use.

Genetic diversity of Venezuelan alphaviruses and circulation of a Venezuelan equine encephalitis virus subtype IAB strain during an interepizootic period.

Several species of alphaviruses have been previously described in the Americas, some of which are associated with encephalitis and others are associated with arthralgia. Venezuelan equine encephalitis virus (VEEV) and eastern equine encephalitis virus (EEEV) are endemic to Venezuela, with the former being responsible for major outbreaks of severe and often fatal disease in animals and humans. The aim of this study was to analyze the genetic diversity of Venezuelan alphaviruses isolated during two decades (1973-1999) of surveillance in northern Venezuela.

HIV-1 and GBV-C co-infection in Venezuela.

Introduction: Co-infection with GB virus C (GBV-C) in patients infected with human immunodeficiency virus 1 (HIV-1) has been associated with prolonged survival. The aim of this study was to evaluate the prevalence of GBV-C infection among HIV-1-infected patients in Venezuela, and to determine the effects of the co-infection on the levels of relevant cytokines.

Methodology: Plasma samples were collected from 270 HIV-1-seronegative and 255 HIV-1-seropositive individuals.

HIV-1 epidemic in Warao Amerindians from Venezuela: spatial phylodynamics and epidemiological patterns.

Objectives: We previously reported HIV-1 infection in Warao Amerindians from Venezuela. The aim of this study was to evaluate the extent and the dynamic of HIV-1 dissemination in eight Warao communities.

Design And Setting: HIV-1 infection was evaluated in 576 Warao Amerindians from the Orinoco Delta.

Unusual presentation of hepatitis B serological markers in an Amerindian community of Venezuela with a majority of occult cases.

Background: Occult hepatitis B infection (OBI) is characterized by the presence of hepatitis B virus (HBV) DNA in the absence of HBsAg in the serum of patients. The aim of this study was to characterize HBV infection among a Piaroa community, an Amerindian group which exhibits significant evidence of exposure to HBV but relatively low presence of HBsAg, and to explore the presence of OBI in this population.

Results: Of 150 sera, with 17% anti-HBc and 1.

Absence of primary integrase resistance mutations in HIV type 1-infected patients in Venezuela.

The preexistence of mutations to integrase inhibitors in HIV-1-infected Venezuelan patients was evaluated. The integrase region of the HIV-1 genome was amplified by nested-PCR and sequenced in 57 isolates from both naive (n = 24) and treated patients who received protease and/or reverse transcriptase inhibitors (PI and RTI, n = 33), but were never exposed to integrase inhibitors. Only one primary integrase resistance mutation, not conferring drug resistance by itself, was found among these patients, although several minor viral mutations, equally distributed among naive and PI- and RTI-treated patients, were also found.

Deletion, insertion and stop codon mutations in vif genes of HIV-1 infecting slow progressor patients.

Background: Variable progression towards AIDS has been described and has been related to viral and host factors. Around 10% of the HIV-1 infected patients are slow progressors (SP), not presenting with AIDS disease signs even after more than 10 years of infection. Viral gene defects have been associated with the disease progression but more studies are still needed.

Comparative analysis of polymorphisms in the HIV type 1 pol gene in the proviral DNA and viral RNA in the peripheral compartment.

The aim of this study was to evaluate the presence of mutations and polymorphisms associated with drug resistance among HIV-1-infected patients in proviral DNA and viral RNA extracted from PBMCs and plasma, respectively, in 34 HIV-1-infected patients (11 naive and 23 receiving HAART). Additional drug resistance mutations were found in only one compartment in 14 of 23 treated patients. Mutations conferring resistance to an additional drug were found in plasma in only 7 of 23 patients.

Prevalence of antiretroviral drug resistance among treatment-naive and treated HIV-infected patients in Venezuela.

An in-house, low-cost method was developed to determine the genotypic resistance of immunodeficiency virus type 1 (HIV-1) isolates. All 179 Venezuelan isolates analysed belonged to subtype B. Primary drug resistance mutations were found in 11% of 63 treatment-naïve patients.

HIV diversity in Venezuela: predominance of HIV type 1 subtype B and genomic characterization of non-B variants.

The aim of this study was the analysis of human immunodeficiency virus (HIV) diversity in Venezuela, and the characterization of variants other than subtype B. A total of 425 HIV isolates, collected between 2003 and 2008, were analyzed. The sequence of at least one genomic region (Pol, Env, Vif, or Nef ) was available for all of them and at least two genomic regions were analyzed in 46% of them.

Comparative antiviral (HIV) photoactivity of metalized meso- tetraphenylsulfonated porphyrins.

We have carried out the study of the photochemical properties of a series of synthetic meso-tetraphenylsulfonated porphyrins (TPPMS4) bonded to several metal ions such as: Cu(II), Zn(II), Pd(II), Mn(II), Fe(III), Ni(II) and Co(II) for the optimization of their clinical applications as antiviral agents against the human immunodeficiency virus (HIV-1) as well as the study of the in vitro antiviral photoinactivation mechanisms with future application in blood sterilization. A selective inhibition has been determined in the viral growth (HIV-1) when this is irradiated in the presence of the complex TPPFeS4 and TPPMnS4 (photosensitizer-mediated Type I reaction) as well as in the 1O2-mediated (Type II reaction) in the presence of TPPPdS4 and TPPZnS4, remaining cellular viability unaltered in each case.

Levels of complement C3 and C4 components in Amerindians living in an area with high prevalence of tuberculosis.

The levels of complement C3 and C4 components were determined in non-indigenous (creoles) and indigenous (Warao) populations, the latter with an extremely high tuberculosis (TB) rate. Serum samples from 209 adults were studied and classified in 4 groups taking into account tuberculin skin tests (TST): (1) the group of Warao patients (58 positive for the TST, WP TST+ and 9 negative for the TST, WP TST-), (2) the group of creole patients (34 positive for the TST, CP TST+ and 9 negative for the TST, CP TST-), (3) the group of healthy Warao controls (38 positive and 14 negative for TST, WC TST+ and WC TST-, respectively), (4) the creole controls (26 positive and 21 negative for the TST, CC TST+ and CC TST-, respectively). With respect to the results concerning the measurement of both complement C3 and C4 components with the exception of the WC TST and the CC groups, the WP TST+ and WP TST- as well as WC TST+ groups showed a significant frequency of individuals with decreased levels of complement C3 component (20.