Molecular assays for determining sulphadoxine-pyrimethamine drug resistance in India: a systematic review.

A plethora of studies analyse the molecular markers of drug resistance and hence help in guiding the evidence-based malaria treatment policies in India. For reporting mutations, a number of techniques including DNA sequencing, restriction-fragment length polymorphism and mutation-specific polymerase chain reaction have been employed across numerous studies, including variations in the methodology used. However, there is no sufficient data from India comparing these methods as well as report the prevalence of polymorphisms in SP drug resistance molecular markers independently using such methods.

Epidemiology of malaria and anemia in high and low malaria-endemic North-Eastern districts of India.

Anemia and malaria are the two major public health problems that lead to substantial morbidity and mortality. Malaria infection destroys erythrocytes, resulting in low hemoglobin (Hb) levels known as anemia. Here we report the determinants of anemia in high and low malaria-endemic areas that would help understand which parasite densities, age, and gender-associated low Hb levels.

Mutations in Pfcrt and Pfmdr1 genes of Plasmodium falciparum isolates from two sites in Northcentral and Southwest Nigeria.

The ability of malaria parasites to develop resistance to antimalarial drugs has made it necessary to continuously survey malaria parasite populations for resistance markers. Mutations in specific malaria parasite genes confer resistance to antimalarial drugs. The study compared mutations in Pfcrt and Pfmdr1 genes of P.

Diagnostic performance of rapid diagnostic test, light microscopy and polymerase chain reaction during mass survey conducted in low and high malaria-endemic areas from two North-Eastern states of India.

An early and accurate diagnosis followed by prompt treatment is pre-requisite for the management of any disease. Malaria diagnosis is routinely performed by microscopy and rapid diagnostic tests (RDTs) in the field settings; however, their performance may vary across regions, age and asymptomatic status. Owing to this, we assessed the diagnostic performance of conventional and advanced molecular tools for malaria detection in low and high malaria-endemic settings.

Asymptomatic low-density Plasmodium infection during non-transmission season: a community-based cross-sectional study in two districts of North Eastern Region, India.

Background: Malaria elimination requires targeting asymptomatic and low-density Plasmodium infections that largely remain undetected. Therefore we conducted a cross-sectional study to estimate the burden of asymptomatic and low-density Plasmodium infection using conventional and molecular diagnostics.

Methods: A total of 9118 participants, irrespective of age and sex, were screened for malaria using rapid diagnostic tests (RDTs), microscopy and polymerase chain reaction.

Redox interactome in malaria parasite Plasmodium falciparum.

The malaria-causing parasite Plasmodium falciparum is a severe threat to human health across the globe. This parasite alone causes the highest morbidity and mortality than any other species of Plasmodium. The parasites dynamically multiply in the erythrocytes of the vertebrate hosts, a large number of reactive oxygen species that damage biological macromolecules are produced in the cell during parasite growth.

The nucleotide specificity of succinyl-CoA synthetase of Plasmodium falciparum is not determined by charged gatekeeper residues alone.

Substrate specificity of an enzyme is an important characteristic of its mechanism of action. Investigation of the nucleotide specificity of Plasmodium falciparum succinyl-CoA synthetase (SCS; PfSCS) would provide crucial insights of its substrate recognition. Charged gatekeeper residues have been shown to alter the substrate specificity via electrostatic interactions with approaching substrates.

Prevalence and spectrum of mutations causing G6PD deficiency in Indian populations.

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human erythroenzymopathy affecting around 10% of the world population. India is endemic for malaria and antimalarial drugs are known to induce haemolysis in G6PD deficient individuals. Here we report the prevalence as well as the molecular diversity of G6PD deficiency in geographical regions of India.

Evaluation of Implementation of Intermittent Screening and Treatment for Control of Malaria in Pregnancy in Jharkhand, India.

This study evaluated intermittent screening and treatment during pregnancy (ISTp) for malaria using rapid diagnostic tests (RDTs) at antenatal care (ANC) compared with passive case detection within the routine health system. The mixed-method evaluation included two cross-sectional household surveys (pre- and post-implementation of ISTp), in-depth interviews with health workers, and focus group discussions (FGDs) with pregnant women. Differences in proportions between surveys for a number of outcomes were tested; 553 and 534 current and recently pregnant women were surveyed (pre- and post-implementation, respectively).

Novel molecular diagnostic technique for detecting the different species of Plasmodium.

Background: Sensitive diagnostic techniques are needed for timely detection of malaria parasite and disease control. Molecular diagnostic techniques involving Polymerase chain reaction (PCR) with 18 s rRNA as a known diagnostic target with an overall sensitivity of 10 parasites per microliter is used as a gold standard. Till date, no attempt has been undertaken to develop a technique for the identification of four Plasmodium species in a single step PCR combined with restriction digestion with enzymes.

First report of glucose-6-phosphate dehydrogenase (G6PD) variants (Mahidol and Acores) from malaria-endemic regions of northeast India and their functional evaluations in-silico.

G6PD deficiency results from numerous mutations in the G6PD gene and can cause alterations in enzyme function up to varying degrees. P. vivax malaria infections require G6PD deficiency screening because of the potential risk of haemolysis by the gametocytocidal drug (primaquine) during the radical treatment.

Effectiveness of intermittent screening and treatment for the control of malaria in pregnancy: a cluster randomised trial in India.

Background: The control of malaria in pregnancy (MiP) in India relies on testing women who present with symptoms or signs suggestive of malaria. We hypothesised that intermittent screening and treatment for malaria at each antenatal care visit (ISTp) would improve on this approach and reduce the adverse effects of MiP.

Methods: A cluster randomised controlled trial comparing ISTp versus passive case detection (PCD) was conducted in Jharkhand state.

Geographic Plasmodium falciparum sarcoplasmic reticulum Ca2+ ATPase (PfSERCA) genotype diversity in India.

Plasmodium falciparum sarcoplasmic reticulum Ca ATPase (PfSERCA) is sarcoplasmic reticulum membrane bound transporter to regulate cytosol Ca ions. Ca act as secondary messenger and play important role in differentiation of parasite during its life cycle. Present study is epidemiological surveillance of PfSERCA (Pf3D7_0106300) gene fragment harboring 263, 402, 431 codon to look for its single nucleotide polymorphism which is well documented to be associated with Artemisinin tolerance.

A Simple and Cost-Effective Freeze-Thaw Based Method for DNA Extraction from Dried Blood Spot.

Background: Available DNA isolation methods for involve numerous processing steps, adding to the cost and conferring risk of contamination. Here we devise a simple and cost-effective method for direct extraction of DNA from dried filter paper spot (DBS), appropriate for resource-limited setups.

Methods: The protocol involves simple freezing and thawing of DBS, neither involves any purification step nor any chemical reagent.

Efficacy of two artemisinin-based combinations for the treatment of malaria in pregnancy in India: a randomized controlled trial.

Background: In India, the recommended first-line treatment for malaria in the second and third trimester of pregnancy is artesunate + sulfadoxine-pyrimethamine (AS+SP). However, data on safety and efficacy of artemisinin-based combination therapy (ACT) in pregnancy is limited. This study assessed the safety and efficacy of AS+SP and artesunate + mefloquine (AS+MQ) for treatment of Plasmodium falciparum in pregnancy in India.

Spatio-temporal distribution of PfMDR1 polymorphism among uncomplicated Plasmodium falciparum malaria cases along international border of north east India.

PfMDR1 single nucleotide polymorphisms (SNP) are good correlate markers for antimalarial drug resistance worldwide. Present study is a comprehensive view of screening of PfMDR1 polymorphism to antimalarials practiced with geography and time. Study sites Mizoram, Tripura, Meghalaya chosen are at multivariate drug pressure due to cross border migration and transmission.

Correlation of sensitivity of chloroquine and other antimalarials with the partner drug resistance to malaria in selected sites of India.

Background: Antimalarial drug resistance is a potential threat for control and elimination of malaria. To ascertain the status of antimalarial drug resistance at the study sites, correlation between in vitro drug sensitivity pattern and drug resistance molecular markers in Plasmodium falciparum malaria was undertaken.

Materials And Methods: Polymorphisms in P.

Establishment and application of a novel isothermal amplification assay for rapid detection of chloroquine resistance (K76T) in Plasmodium falciparum.

Chloroquine (CQ) resistance in Plasmodium falciparum is determined by the mutations in the chloroquine resistance transporter (Pfcrt) gene. The point mutation at codon 76 (K76T), which has been observed in more than 91% of P. falciparum isolates in India, is the major determinant of CQ resistance.

Comparison of WHO Mark III and HRP II ELISA for sensitivity of .

Background & Objectives: Antimalarial drug resistance is a serious challenge to malaria control worldwide. In vitro sensitivity assays provide an early indication of emerging drug resistance. In vitro susceptibility of field and culture adapted Plasmodium falciparum isolates to different antimalarials was compared using two Methods: World Health Organization (WHO) micro-test (MARK III) and histidine rich protein II (HRP II) based enzyme- linked immunosorbent assay (ELISA).

sensitivity pattern of chloroquine and artemisinin in .

Artemisinin (ART) and its derivatives form the mainstay of antimalarial therapy. Emergence of resistance to them poses a potential threat to future malaria control and elimination on a global level. It is important to know the mechanism of action of drug and development of drug resistance.

Emerging polymorphisms in falciparum Kelch 13 gene in Northeastern region of India.

Background: Recent reports of emergence and spread of artemisinin resistance in the Southeast Asia region, including Myanmar, pose a greater threat to malaria control and elimination in India. Whole genome sequencing studies have associated mutations in the K13 propeller gene (k13), PF3D7_1343700 with artemisinin resistance both in vitro and in vivo. The aim of the present study was to find the k13 gene polymorphisms in Plasmodium falciparum parasites from the three sites in the Northeast region of India, bordering Bangladesh and Myanmar.

Engineering Nucleotide Specificity of Succinyl-CoA Synthetase in Blastocystis: The Emerging Role of Gatekeeper Residues.

Charged, solvent-exposed residues at the entrance to the substrate binding site (gatekeeper residues) produce electrostatic dipole interactions with approaching substrates, and control their access by a novel mechanism called "electrostatic gatekeeper effect". This proof-of-concept study demonstrates that the nucleotide specificity can be engineered by altering the electrostatic properties of the gatekeeper residues outside the binding site. Using Blastocystis succinyl-CoA synthetase (SCS, EC 6.

Monitoring the efficacy of antimalarial medicines in India via sentinel sites: Outcomes and risk factors for treatment failure.

Background & Objectives: To combat the problem of antimalarial drug resistance, monitoring the changes in drug efficacy over time through periodic surveillance is essential. Since 2009, systematic and continuous monitoring is being done through nationwide sentinel site system. Potential early warning signs like partner drug resistance markers were also monitored in the clinical samples from the study areas.