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. Therefore, all data from Indian studies available for molecular marker studies of
Plasmodium falciparum
drug resistance to sulphadoxine-pyrimethamine was gathered, and a systematic review was performed. This systematic review identifies the molecular methods in use in India and compares each method for detecting sulphadoxine-pyrimethamine drug resistance marker. To delay the spread of drug-resistant parasite strains, a simplified and standardized molecular method is much needed which can be obtained by analysing the performance of each method in use and answering the necessity of newer methodological approaches.
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. To relieve this intense oxidative stress, the parasite employs an NADPH-dependent thioredoxin and glutathione system that acts as an antioxidant and maintains redox status in the parasite. The mutual interaction of both redox proteins is involved in various biological functions and the survival of the erythrocytic stage of the parasite. Since the
Plasmodium
species is deficient in catalase and classical glutathione peroxidase, so their redox balance relies on a complex set of five peroxiredoxins, differentially positioned in the cytosol, mitochondria, apicoplast, and nucleus with partly overlapping substrate preferences. Moreover,
Plasmodium falciparum
possesses a set of members belonging to the thioredoxin superfamily, such as three thioredoxins, two thioredoxin-like proteins, one dithiol, three monocysteine glutaredoxins, and one redox-active plasmoredoxin with largely redundant functions. This review paper aims to discuss and encapsulate the biological function and current knowledge of the functional redox network of
Plasmodium falciparum
.
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. We performed mass blood surveys in low and high endemic regions of two North-Eastern districts from the states of Assam and Meghalaya. A total of 3322 individuals were screened for malaria using RDT, microscopy and PCR and measures of diagnostic accuracy were estimated. Out of 3322 individuals, 649 (19.5%) were detected with malaria parasite. Asymptomatic were 86.4% (2872/3322), of which 19.4% (557/2872) had
Plasmodium
infection. The sensitivity and specificity of microscopy were 42.7% and 99.3%, and RDT showed 49.9% and 90.4%, respectively, considering PCR as standard. RDT (AUC: 0.65 vs 0.74;
p
= 0.001) and microscopy (AUC: 0.64 vs 0.76;
p
< 0.0001) performances were significantly lower in low compared to high endemic areas. True positive rate was lower in asymptomatics but true negative rate was found similar to symptomatic individuals. The conventional diagnostic tools (RDT and microscopy) had detected malaria in children with nearly twofold greater sensitivity than in the adults (
p
< 0.05). To conclude, asymptomatics, adults and low malaria-endemic regions require major attention due to mediocre performance of conventional diagnostic tools in malaria detection.
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. To overcome the limitations and challenges of traditional methods, in this investigation we developed an easy to use loop mediated isothermal amplification (LAMP) protocol for rapid detection of the K76T mutation associated with CQ resistance in P. falciparum with naked eye visualization. In- house designed primers were synthesized and optimized to specifically distinguish the CQ resistant mutants of P. falciparum. The LAMP reaction was optimal at 61 °C for 60 min and calcein dye was added prior to amplification to enable visual detection. We demonstrate the detection limit of <2 ng/μl respectively, supporting the high sensitivity of this calcein based LAMP method. To the best of our knowledge this is the first report on the establishment of an easy, reliable and cost effective LAMP assay for rapid and specific detection of highly CQ resistance in P. falciparum malaria.
We report Indian Plasmodium falciparum field isolates lacking both Pfhrp2 and Pfhrp3 genes. Lack of amplification of Pfhrp2, Pfhrp3 and their flanking genes in two P. falciparum field isolates of ...India. Row 1: Lanes 1 and 7=100bp marker, Lanes 6 and 12=negative control (distilled water), Lanes 2–5=Pfhrp2 gene, Lanes 8–11=Pfhrp3 gene. Row 2: Lanes 1 and 7=100bp marker, Lanes 6 and 12=negative control (distilled water), Lanes 2–5=upstream Pfhrp2 gene, Lanes 8–11=downstream Pfhrp2 gene. Display omitted
► Failure to express Pfhrp2 and Pfhrp3 due to gene deletion may contribute to variable performance of malaria RDTs. ► We report two Indian P. falciparum isolates lacking these genes. ► Genetic deletion of Pfhrp2 and Pfhrp3 may lead to false negative results in RDTs.
Genetic polymorphisms in diagnostic antigens are important factors responsible for variable performance of rapid diagnostic tests. Additionally, the failure of antigen expression due to gene deletion may also contribute to variable performance. We report Indian Plasmodium falciparum field isolates lacking both Pfhrp2 and Pfhrp3 genes leading to false negative results of rapid diagnostic tests. The study highlights need to determine the prevalence of P. falciparum isolates lacking these genes in larger field populations in India.
Mucormycosis, also known as Zygomycosis or Black Fungus, is an infection caused in humans via various causative agents from the Zygomycetes class. Several countries including India is afflicted by ...the covid-19 virus, which has infected approximately 3.7 million people across the country. Some of the corona-positive patients suffer from another fatal infection, Mucormycosis, commonly known as Black Fungus. The strategy should be to administer an effective antifungal drug as soon as possible at the optimum dose. However, India being an epicenter of Diabetes with enormous 80 million diabetics, is of particular importance in the present scenario of the COVID pandemic. COVID therapy with Steroids and immune suppressants has increased the chances of infection in various individuals within the country with weaker immune system responses. The main purpose of this paper is to enlighten the community about the involvement of mucormycosis in covid-19 affected population and basic insights of its invasion. Keywords Mucormycosis, Black Fungus, Covid-19, Diabetes Mellitus, Amphotericin B, Immunosuppression, Apophysomyces, Renal Failure, Corticosteroids
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.
This open-label, randomized clinical trial was conducted from October 2010 to December 2013 at three sites in India (Ranchi and Jamshedpur in Jharkhand state, and Rourkela in Odisha state). Pregnant women in the second or third trimester who had P. falciparum mono-infection of any parasite density with or without fever were randomized to receive AS+SP or AS+MQ. Blood slides and filter paper samples for Polymerase Chain Reaction (PCR) were collected on days 0, 1, 2, 3, 14, 21, 28, 42 and 63 post treatment. Women were followed up at delivery and at day 42 postpartum.
Two hundred and forty-eight women of 7064 pregnant women (3.5%) who were screened at monthly antenatal clinics had a P. falciparum mono-infection and were randomized to receive AS+SP (125) or AS+MQ (123) and all of these women were included in the intention to treat (ITT) analysis. The primary endpoint of an adequate clinical and parasite response (ACPR) on day 63 was not available for 9 women who were counted as treatment failure in the ITT analysis. In the ITT population, the ACPR was 121/125 (96.8%; 95% Confidence interval (CI) 92.0-99.1%) in the AS+SP group and 117/123 (95.1%; 95% CI 89.7-98.2) in the AS+MQ group. Among the 239 women (121 from the AS+SP arm and 118 from the AS+MQ arm) who completed the day 63 follow up (per protocol analysis) the ACPR was 100% in the AS+SP group and 99.2% (117/118) in the AS+MQ group. There were five serious adverse events (SAE) among pregnant women (4 in the AS+SP group and 1 in the AS+MQ group) and 13 fetal/neonatal SAEs (7 in the AS+SP group and 6 in the AS+MQ) but none of them were related to the study drugs. A higher proportion of women in the AS+MQ arm reported vomiting within 7 days post-treatment than did women in the AS+SP arm (6.9 vs. 1.6%; p = 0.001).
Both AS+SP and AS+MQ are safe and effective for treatment of uncomplicated falciparum malaria in pregnancy in India. Trial registration CTRI This study is registered with Clinical Trial Registry India (CTRI), number CTRI/2009/091/001055. Date of Registration 11 January 2010, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=1185&EncHid=&userName=anvikar.
The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination ...Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness.
Rapid diagnostic tests (RDTs) have revolutionized the diagnosis of malaria. Among the various factors affecting RDTs sensitivity is genetic variation of the antigen used. The genetic variation in ...PfHRP2 and PfHRP3 proteins was studied among the Indian Plasmodium falciparum isolates.
One hundred and forty isolates of P. falciparum were collected from six geographical regions of India. Target genes encoding PfHRP2 and PfHRP3 antigens were sequenced to study genetic polymorphism. Minimum detection limit giving a positive rapid diagnostic test was also determined.
Extensive variations were observed in amino acid repeat types of PfHRP2 and PfHRP3. PfHRP2 exhibited more polymorphism than PfHRP3. Significant relation was observed between type 2 and type 7 repeats and RDT detection rate as higher number of these repeats showed better sensitivity with RDTs.
The results provide insights into the genetic diversity of Pfhrp2 and Pfhrp3 genes among Indian P. falciparum population and its relation to RDT sensitivity.
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.
A total of 20,896 individuals (11,838 males and 9058 females) were screened by DPIP dye decolorisation method followed by quantitation of G6PD enzyme activity on the suspected samples. Molecular analysis was undertaken in a total of 350 G6PD deficient individuals by PCR-RFLP and DNA sequencing. A structural characteristic of the novel variant was deduced by using DynaMut web-server. The prevalence rate of G6PD deficiency varied between 0.8 and 6.3% with an overall prevalence of 1.9%. A total of twelve mutations were identified. Of the total deleterious alleles detected G6PD Orissa (56.5%) was found to be the most predominant variant followed by G6PD Mediterranean (23.6%). G6PD Mediterranean, G6PD Kaiping and G6PD Mahidol were found to be severely deficient variant and 14.1% of them showed undetectable activity. A novel mutation c.544C➔G (R182G) in exon 6 was identified in one tribal male where substitution of arginine by glycine, likely causes the alteration in the alpha helix leading to disruption of secondary structure of the protein.
There are large differences in the distribution of G6PD causal variants between Indian states, and this may have implications for the treatment in the malaria endemic areas.
•Prevalence rate of G6PD deficiency varied between 0.8 and 6.3% with an overall prevalence of 1.9% in Indian population studied.•G6PD Mediterranean, Kaiping and Mahidol variants were severely deficient and 14.1% of them showed undetectable activity.•Substitution of R182G, likely alters in the alpha helix leading to disruption of secondary structure of the protein .•High prevalence of G6PD deficiency and severe variants demonstrate the need for G6PD screening in the malaria endemic areas.
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