Geographical distribution and genetic characterization of pfhrp2 negative Plasmodium falciparum parasites in the Peruvian Amazon.

Malaria rapid diagnostic tests (RDTs) have been evaluated in the Peruvian Amazon region and their performance has been variable. This region is known for being the first with documented evidence of wild Plasmodium falciparum parasites lacking pfhrp2 and pfhrp3 genes, leading to false-positive results with HRP2-based RDTs. In our attempt to further characterize the deletion pattern of these genes and their evolutionary relationship, 93 P.

Morphological and molecular characterization of an Elaeis oleifera (H.B.K) Cortes germplasm collection located in Ucayali, Peru.

The African oil palm (Elaeis guineensis Jacq) is a crop that is widely distributed in tropical regions around the world; however, this crop is subject to limitations such as rapid trunk growth and susceptibility to bud rot and red ring diseases particularly in South America. To overcome these limitations, national breeding and conservation programs have been established, and there is a need to identify parental palms from natural populations of the American oil palm (E. oleifera H.

Whole-Genome Sequencing of a Salmonella enterica subsp. enterica Serovar Infantis Strain Isolated from Broiler Chicken in Peru.

This report shows the whole-genome sequence of the multidrug-resistant subsp. serovar Infantis strain FARPER-219. Antibiotic resistance genes are found mainly in the plasmid.

Evaluation of Plasmodium falciparum MSP10 and its development as a serological tool for the Peruvian Amazon region.

Background: Different antigens are needed to characterize Plasmodium falciparum infection in terms of seroreactivity and targets for invasion inhibition, in order to guide and identify the proper use of such proteins as tools for the development of serological markers and/or as vaccine candidates.

Methods: IgG responses in 84 serum samples from individuals with P. falciparum infection [classified as symptomatic (Sym) or asymptomatic (Asym)], or acute Plasmodium vivax infection, from the Peruvian Amazon region, were evaluated by enzyme-linked immunosorbent assays specific for a baculovirus-produced recombinant protein P.

Glycoprotein G (gG) production profile during infectious laryngotracheitis virus (ILTV) infection.

Glycoprotein G (gG) is a conserved protein, and it has been described as a chemokine-binding protein in most members of the alphaherpesviruses. In case of the infectious laryngotracheitis virus (ILTV), an alphaherpesvirus that infects chickens, this protein is a virulence factor that plays an immunomodulatory role in the chicken immune response. Nevertheless, the gG production profile during ILTV infection has not yet been studied.

Phylogenetic Evidence of a Close Relationship between the Peruvian Strain Vfar-043 and Two U.S. Origin Iltv Field Strains.

Infectious laryngotracheitis virus (ILTV) is the causative agent of an acute respiratory avian disease known as infectious laryngotracheitis (ILT), which has been associated with economic losses in poultry. The presence of ILTV has been widely reported in South American countries; however, only one full genomic sequence (VFAR-043 strain) has been recently published, from an outbreak in Peru. The aim of this study was to determine the genetic relationship of the Peruvian strain with other ILTV strains from different geographic regions.

Whole-Genome Sequence of Sphingomonas sp. Strain FARSPH, a Novel Sf9 Insect Cell Culture Contaminant.

Here, we report the whole-genome sequence of Sphingomonas sp. strain FARSPH, isolated from an insect cell line as a contaminant. FARSPH shared high identity with Sphingomonas melonis and Sphingomonas aquatilis strains.

Plasmodium vivax Diversity and Population Structure across Four Continents.

Plasmodium vivax is the geographically most widespread human malaria parasite. To analyze patterns of microsatellite diversity and population structure across countries of different transmission intensity, genotyping data from 11 microsatellite markers was either generated or compiled from 841 isolates from four continents collected in 1999-2008. Diversity was highest in South-East Asia (mean allelic richness 10.

Genetic diversity of VAR2CSA ID1-DBL2Xb in worldwide Plasmodium falciparum populations: impact on vaccine design for placental malaria.

In placental malaria (PM), sequestration of infected erythrocytes in the placenta is mediated by an interaction between VAR2CSA, a Plasmodium falciparum protein expressed on erythrocytes, and chondroitin sulfate A (CSA) on syncytiotrophoblasts. Recent works have identified ID1-DBL2Xb as the minimal CSA-binding region within VAR2CSA able to induce strong protective immunity, making it the leading candidate for the development of a vaccine against PM. Assessing the existence of population differences in the distribution of ID1-DBL2Xb polymorphisms is of paramount importance to determine whether geographic diversity must be considered when designing a candidate vaccine based on this fragment.

Relationship of regulatory T cells to Plasmodium falciparum malaria symptomatology in a hypoendemic region.

Background: Previous data have suggested that regulatory T cells (Tregs) balance protective immune responses with immune mediated pathology in malaria. This study aimed to determine to test the hypothesis that Treg proportions or absolute levels are associated with parasitaemia and malaria symptoms.

Methods: Treg cells were quantified by flow cytometry as CD4+ CD25+, Foxp3+, CD127(low) T cells.

Multiple genetic origins of histidine-rich protein 2 gene deletion in Plasmodium falciparum parasites from Peru.

The majority of malaria rapid diagnostic tests (RDTs) detect Plasmodium falciparum histidine-rich protein 2 (PfHRP2), encoded by the pfhrp2 gene. Recently, P. falciparum isolates from Peru were found to lack pfhrp2 leading to false-negative RDT results.

Anti-Plasmodium falciparum invasion ligand antibodies in a low malaria transmission region, Loreto, Peru.

Background: Erythrocyte invasion by Plasmodium falciparum is a complex process that involves two families; Erythrocyte Binding-Like (EBL) and the Reticulocyte Binding-Like (PfRh) proteins. Antibodies that inhibit merozoite attachment and invasion are believed to be important in mediating naturally acquired immunity and immunity generated by parasite blood stage vaccine candidates. The hypotheses tested in this study were 1) that antibody responses against specific P.

Rapid diagnostic tests for malaria diagnosis in the Peruvian Amazon: impact of pfhrp2 gene deletions and cross-reactions.

Background: In the Peruvian Amazon, Plasmodium falciparum and Plasmodium vivax malaria are endemic in rural areas, where microscopy is not available. Malaria rapid diagnostic tests (RDTs) provide quick and accurate diagnosis. However, pfhrp2 gene deletions may limit the use of histidine-rich protein-2 (PfHRP2) detecting RDTs.

Field evaluation of a rapid diagnostic test (Parascreen) for malaria diagnosis in the Peruvian Amazon.

Background: The rapid diagnostic tests for malaria (RDT) constitute a fast and opportune alternative for non-complicated malaria diagnosis in areas where microscopy is not available. The objective of this study was to validate a RDT named Parascreen under field conditions in Iquitos, department of Loreto, Peru. Parascreen is a RDT that detects the histidine-rich protein 2 (HRP2) antigen from Plasmodium falciparum and lactate deshydrogenase from all Plasmodium species.

A large proportion of P. falciparum isolates in the Amazon region of Peru lack pfhrp2 and pfhrp3: implications for malaria rapid diagnostic tests.

Background: Malaria rapid diagnostic tests (RDTs) offer significant potential to improve the diagnosis of malaria, and are playing an increasing role in malaria case management, control and elimination. Peru, along with other South American countries, is moving to introduce malaria RDTs as components of malaria control programmes supported by the Global Fund for AIDS, TB and malaria. The selection of the most suitable malaria RDTs is critical to the success of the programmes.