Humoral and cellular immune response to AZD1222 /Covishield and BV152/Covaxin COVID-19 vaccines among adults in India.

Several COVID-19 vaccines were developed using different approaches to prevent both symptomatic COVID-19 cases and fatalities. The adults were vaccinated with two doses of AZD1222/Covishield (n = 77) [manufactured by Serum Institute of India Pvt Ltd] vaccine and BV152/Covaxin (n = 99) [manufactured by Bharat Biotech] vaccine. They were assessed for immune response at pre-vaccination, 1 month post first and 6 months post second dose for anti-SARS-CoV-2 IgG antibody, surrogate neutralizing antibody (NAbs), immune phenotypes, antigen specific NK, B and T cell response, their effector functionality by ELISPOT and plasma cytokine profile. Both vaccines elicited enhanced IgG antibody and Nab levels compared to the baseline. BV152/Covaxin, the whole virus inactivated vaccine exhibited higher IgG (70% vs 100%), Nab (90% vs 100%), and robust T cell (31% vs 96%) responses at 6 months post second dose compared to 1 month post first dose justifying the utility of the second dose. Detection of SARS-CoV-2 WV and S1 specific CD4+ central T cell memory response in AZD1222/Covishield vaccinee at 6 months post second dose and higher CD4+ and CD8+ naïve and central memory T cell response in BV152/Covaxin vaccinee at 1 month post first dose indicated the involvement of memory T cells. Persistent IgG and NAb responses along with IgG+B and IgG+memory B cells in AZD1222/Covishield recipients at 6 months post second dose indicated sustained immune memory response. Continued heightened IFN-γ secreting T cell response (ELISPOT) displayed by both the vaccine platforms could serve as a co correlate of protection, further to evaluation in follow up studies. Overall, our data suggest that coordinated functions of humoral and cellular branches of adaptive immunity may pave ways toward protective immunity against COVID-19.

Descriptive, Hospital-Based, 10-Year Study of Malaria Transmission in Goa, a Southwest Indian State in the Malaria Elimination Phase.

The South Asia International Center of Excellence for Malaria Research, an NIH-funded collaborative program, investigated the epidemiology of malaria in the Indian state of Goa through health facility-based data collected from the Goa Medical College and Hospital (GMC), the state's largest tertiary healthcare facility, between 2012 and 2021. Our study investigated region-specific spatial and temporal patterns of malaria transmission in Goa and the factors driving such patterns. Over the past decade, the number of malaria cases, inpatients, and deaths at the GMC decreased significantly after a peak in 2014-2015. However, the proportion of severe malaria cases increased over the study period. Also, a trend of decreasing average parasitemia and increasing average gametocyte density suggests a shift toward submicroscopic infections and an increase in transmission commitment characteristic of low-transmission regions. Although transmission occurred throughout the year, 75% of the cases occurred between June and December, overlapping with the monsoon (June-October), which featured rainfall above yearly average, minimal diurnal temperature variation, and high relative humidity. Sociodemographic factors also had a significant association with malaria cases, with cases being more frequent in the 15-50-year-old age group, men, construction workers, and people living in urban areas within the GMC catchment region. Our environmental model of malaria transmission projects almost negligible transmission at the beginning of 2025 (annual parasitic index: 0.0095, 95% CI: 0.0075-0.0114) if the current control measures continue undisrupted.

Broadly Reactive SARS-CoV-2-Specific T-Cell Response and Participation of Memory B and T Cells in Patients with Omicron COVID-19 Infection.

January 2022 onward, India witnessed a sudden increase in Omicron COVID-19 infections, having a mild course that prompted us to identify the key host factors/immune molecules modulating disease course/outcomes. The current study evaluated the percentages of lymphocyte subsets by flowcytometry, SARS-CoV-2 specific T-cell immune response by ELISPOT, estimation of plasma cytokine/chemokine levels on a Bio-plex Multiplex Immunoassay System and anti-SARS-CoV-2 IgG levels by enzyme-linked immunosorbent assay in 19 mild Omicron infected patients, 45 mild SARS-CoV-2 (2020) patients and 36 uninfected controls from India. Natural killer cells, B and memory B cells were high in vaccinated and total Omicron-infected patients groups compared to the mild SARS-CoV-2 (2020) patient group, while CD8+ T cells were high in total Omicron-infected patients group compared to the uninfected control group (p < 0.05 each). Omicron-infected patients had T-cell response against SARS-CoV-2 whole virus, S1 proteins (wild type and delta variant) in 10 out of 17 (59%), 10 out of 17 (59%), and 8 out of 17 (47%), respectively. The current study of Omicron-infected patients elucidates broadly reactive antibody, T-cell response, and participation of memory B and T cells induced by vaccination/natural infection. The limited effect of Omicron's mutations on T-cell response is suggestive of protection from severity. Pro-inflammatory IL-6, IFN-γ, chemokines CCL-2, CCL-3, CCL-4, CCL-5, and IL-8 as potential biomarkers of Omicron infection may have future diagnostic importance. The cellular immune response data in Omicron-infected patients with parental Omicron lineage could serve as a starting point to define the readouts of protective immunity against circulating Omicron subvariants.

Determinants of complementary feeding practices among children aged 6-24 months in urban slums of Pune, Maharashtra, in India.

BACKGROUND: Inequalities in child feeding practices are evident in urban slums in developing nations. Our study identified the determinants of complementary feeding (CF) practices in the informal settings of Pune, India, a district close to the business capital of India. METHODS: Employing a cross-sectional study design, 1066 mother-children dyads were surveyed. Five indicators defined by the WHO were used to study complementary feeding practices. Determinants of complementary feeding practices were identified using multivariate analyses. RESULTS: Timely initiation of CF was reported by 42%. Minimum acceptable diet (MAD), minimum meal frequency (MMF), and Diet Diversity Score > 4 were achieved by 14.9%, 76.5%, and 16.4%, respectively. Continued breastfeeding (CBF) at 2 years, and feeding processed foods were practiced by 94% and 50%, respectively. Among the maternal characteristics, a mother's age > 30 years at pregnancy was less likely to achieve DD [AOR: 0.195 (CI 0.047-0.809)] and MAD [AOR: 0.231 (CI 0.056-0.960)]. Mothers with lower education were less likely to meet MMF [AOR: 0.302 (0.113-0.807)], MAD [AOR: 0.505 (CI 0.295-0.867)] and to introduce formula feeds (FF) [AOR: 0.417 (0.193- 0.899)]. Among obstetric characteristics, birth spacing < 33 months was less likely to achieve DD [AOR: 0.594 (CI 0.365-0.965)] and CBF [AOR: 0.562 (CI: 0.322-0.982)]. Receiving IYCF counseling only during postnatal care hindered the timely initiation of CF [AOR: 0.638 (0.415-0.981)]. Very Low Birth Weight increased the odds of achieving DD [AOR: 2.384 (1.007-5.644)] and MAD [AOR: 2.588(CI: 1.054-6.352)], while low birth weight increased the odds of children being introduced to processed foods [AOR: 1.370 (CI: 1.056-1.776)]. Concerning socio-economic status, being above the poverty line increased the odds of achieving MMF, [AOR: 1.851 (1.005-3.407)]. Other backward castes showed higher odds of achieving MAD [AOR: 2.191 (1.208-3.973)] and undisclosed caste in our study setting decreased the odds of FF [AOR: 0.339 (0.170-0.677)]. Bottle feeding interfered with MMF [AOR: 0.440 (0.317-0.611)] and CBF [AOR: 0.153 (0.105-0.224)]. CONCLUSION: Investing in maternal education and IYCF counseling during both ANC and PNC to provide nutritious complementary foods alongside addressing poverty should be a national priority to prevent the double burden of undernutrition at an early age in informal settings.

Is Infant and Young Child-feeding (IYCF) a potential double-duty strategy to prevent the double burden of malnutrition among children at the critical age? Evidence of association from urban slums in Pune, Maharashtra, India.

BACKGROUND: This study characterized undernutrition among children (0-24 months) by age groups specified for Infant and Young Child-feeding (IYCF) and determined the association between child malnutrition and IYCF. METHODS: This cross-sectional survey recruited mother-children dyads (N = 1443). WHO standards were used to assess nutritional status and IYCF indicators. Multivariate analyses were performed to assess the association between IYCF and nutritional indicators. RESULTS: Stunting, underweight, wasting, overweight, and obesity were prevalent in 33.1%, 26%, 20.2%, 4.6%, and 2.9% of the children, respectively. Age-wise distribution of undernutrition identified severity of stunting and underweight at 10-24 months (median < -1.6 SD; < -1.2 SD; 25th percentile at -2.6 & -2.2 SD respectively) and wasting highest at 0-6 months (25th percentile close to -2SD). Boys manifested higher stunting (lower value -5.2 SD) and were more wasted (lower value -4.7 SD). IYCF prevalence recorded early initiation at 45.2%, exclusive breastfeeding at 23.1%, and prelacteal and bottle-feeding at 37.5 and 22.5% respectively. Child minimum diet diversity (MDD) ≥4 was not achieved by 84%. Minimum meal frequency and minimum acceptable diet were achieved by 75% and 14% respectively. Bottle-feeding increased the odds of wasting [AOR: 1.501 (95% CI: 1.062-2.121)], severe stunting [AOR: 1.595 (95% CI: 1.079-2.358)] and underweight [AOR: 1.519 (95% CI 1.102-2.094)]. Wasting according to BAZ scores was associated with delayed initiation of breastfeeding [AOR: 1.387 (95% CI: 1.018-1.889)] and bottle feeding [AOR: 1.538 (95% CI: 1.087-2.175)]. Delayed introduction of complementary feeding increased the odds of severe stunting [AOR: 2.189 (95% CI: 1.090-4.399)]. Formula feeding increased the odds of underweight [AOR: 1.738 (95% CI: 1.046-2.888)] and obesity [AOR: 4.664 (95% CI: 1.351-16.10)]. Prelacteal feeding increased the odds of severe forms of stunting and underweight by 56% and 79% respectively, and overweight by 96%. CONCLUSION: Setting and age-specific interventions to improve age-appropriate child-feeding practices are vital to address the double burden of malnutrition in the critical age group.

International Center of Excellence for Malaria Research for South Asia and Broader Malaria Research in India.

The Malaria Evolution in South Asia (MESA) International Center of Excellence for Malaria Research (ICEMR) conducted research studies at multiple sites in India to record blood-slide positivity over time, but also to study broader aspects of the disease. From the Southwest of India (Goa) to the Northeast (Assam), the MESA-ICEMR invested in research equipment, operational capacity, and trained personnel to observe frequencies of Plasmodium falciparum and Plasmodium vivax infections, clinical presentations, treatment effectiveness, vector transmission, and reinfections. With Government of India partners, Indian and U.S. academics, and trained researchers on the ground, the MESA-ICEMR team contributes information on malaria in selected parts of India.

Diverse Malaria Presentations across National Institutes of Health South Asia International Center for Excellence in Malaria Research Sites in India.

The Malaria Evolution in South Asia (MESA) International Center for Excellence in Malaria Research (ICEMR) was established by the US National Institutes of Health (US NIH) as one of 10 malaria research centers in endemic countries. In 10 years of hospital-based and field-based work in India, the MESA-ICEMR has documented the changing epidemiology and transmission of malaria in four different parts of India. Malaria Evolution in South Asia-ICEMR activities, in collaboration with Indian partners, are carried out in the broad thematic areas of malaria case surveillance, vector biology and transmission, antimalarial resistance, pathogenesis, and host response. The program integrates insights from surveillance and field studies with novel basic science studies. This is a two-pronged approach determining the biology behind the disease patterns seen in the field, and generating new relevant biological questions about malaria to be tested in the field. Malaria Evolution in South Asia-ICEMR activities inform local and international stakeholders on the current status of malaria transmission in select parts of South Asia including updates on regional vectors of transmission of local parasites. The community surveys and new laboratory tools help monitor ongoing efforts to control and eliminate malaria in key regions of South Asia including the state of evolving antimalarial resistance in different parts of India, new host biomarkers of recent infection, and molecular markers of pathogenesis from uncomplicated and severe malaria.

Plasmodium vivax Strains Use Alternative Pathways for Invasion.

Plasmodium vivax has 2 invasion ligand/host receptor pathways (P. vivax Duffy-binding protein/Duffy antigen receptor for chemokines [DARC] and P. vivax reticulocyte binding protein 2b/transferrin receptor [TfR1]) that are promising targets for therapeutic intervention. We optimized invasion assays with isogenic cultured reticulocytes. Using a receptor blockade approach with multiple P. vivax isolates, we found that all strains utilized both DARC and TfR1, but with significant variation in receptor usage. This suggests that P. vivax, like Plasmodium falciparum, uses alternative invasion pathways, with implications for pathogenesis and vaccine development.

Prevalence and Determinants of Early Initiation (EI), Exclusive Breastfeeding (EBF), and Prelacteal Feeding among Children Aged 0-24 Months in Slums of Pune City, in Maharashtra.

Infant and young child feeding practices remain a public health challenge in India. We determined the socio-demographic risk factors for early initiation, exclusive breastfeeding and prelacteal feeding in the urban slums of Pune city.A cross sectional survey of mother (N=1443) children (< 2 years) dyads was performed. Socio-demographic, maternal and child characteristics were recorded. Breastfeeding practices were assessed using WHO indicators. Multiple logistic regression was employed to model associations between socio-demographic factors and breastfeeding indicators.Early initiation was reported by 45.2%, prelacteal feeding by 37.5% and exclusive breastfeeding by 23.7%. Caesarean delivery decreased the odds of early initiation (AOR: 0.403; 95% CI; 0.303.-0.536) and exclusive breastfeeding (OR: 0.675; 95% CI: 0. 478-0.953), while it increased the odds of prelacteal feeding (AOR: 3.525; 95% CI: 2.653-4.683). Delivery in a public health care facility increased the odds of early initiation (AOR: 1.439; 95% CI: 1.095-1.891) and exclusive breastfeeding (OR: 0.514; 95% CI: 0.366-0.720), while it decreased the odds of prelacteal feeding (AOR: 0.421; 95% CI: 0.318-0.559). Odds of early initiation decreased significantly in very low-birth-weight (AOR: 0.209; CI: 0.76-0.567) whereas, it increased odds of prelacteal feeding (AOR: 1.389; 95% CI: 0.640-3.019), (AOR: 0.483; 95% CI: 0.262-0.889). Religion other than Hindu or Muslim, age of the mother between 26-30 years increased the odds of exclusive breastfeeding and parity <2 increased the odds of prelacteal feeding.Interventions that address setting specific determinants, focusing on local contexts are essential to improve child feeding practices in urban slums.

Study of a hepatitis E virus outbreak involving drinking water and sewage contamination in Shimla, India, 2015-2016.

BACKGROUND: Hepatitis E, caused by hepatitis E virus (HEV), accounts for 50% of acute hepatitis cases in India. We report an outbreak of hepatitis E in Shimla, India, in 2015-2016. METHODS: ICMR-National Institute of Virology (NIV), Pune, received two batches of water samples from Shimla in January 2016 to test for the presence of enterically transmitted hepatitis viruses. Subsequently, 57 icterus patients were tested for various markers of hepatotropic viruses, i.e. anti-HEV IgM/IgG, anti-hepatitis A virus (anti-HAV) IgM/IgG antibodies and HEV RNA. Water samples were screened for HEV and HAV RNA followed by phylogenetic analysis. RESULTS: Overall, 48/57 patients availing municipal water had evidence of HEV infection, detected by serology and RT-PCR. All the water samples tested positive for HEV and HAV RNA, while the patients were negative for anti-HAV IgM antibody, indicating no recent HAV infection. Phylogenetic analysis confirmed the aetiological agent of the current outbreak to be HEV genotype 1. CONCLUSIONS: Serology and RT-PCR confirmed HEV as the aetiology of the outbreak. The absence of new cases of hepatitis A, despite the presence of HAV in the water supply, could be due to previously acquired immunity. Sewage contamination of water leading to faecal-oral transmission of HEV still remains a concern, thus emphasising the need for a vaccination/control strategy.

Decreased In Vitro Artemisinin Sensitivity of Plasmodium falciparum across India.

Artemisinin-based combination therapy (ACT) has been used to treat uncomplicated Plasmodium falciparum infections in India since 2004. Since 2008, a decrease in artemisinin effectiveness has been seen throughout the Greater Mekong Subregion. The geographic proximity and ecological similarities of northeastern India to Southeast Asia may differentially affect the long-term management and sustainability of ACT in India. In order to collect baseline data on variations in ACT sensitivity in Indian parasites, 12 P. falciparum isolates from northeast India and 10 isolates from southwest India were studied in vitro Ring-stage survival assay (RSA) showed reduced sensitivity to dihydroartemisinin in 50% of the samples collected in northeast India in 2014 and 2015. Two of the 10 assayed samples from the southwest region of India from as far back as 2012 also showed decreased sensitivity to artemisinin. In both these regions, kelch gene sequences were not predictive of reduced artemisinin sensitivity, as measured by RSA. The present data justify future investments in integrated approaches involving clinical follow-up studies, in vitro survival assays, and molecular markers for tracking potential changes in the effectiveness of artemisinin against P. falciparum throughout India.

Meta-analysis of Plasmodium falciparum var Signatures Contributing to Severe Malaria in African Children and Indian Adults.

The clinical presentation of severe Plasmodium falciparum malaria differs between children and adults, but the mechanistic basis for this remains unclear. Contributing factors to disease severity include total parasite biomass and the diverse cytoadhesive properties mediated by the polymorphic var gene parasite ligand family displayed on infected erythrocytes. To explore these factors, we performed a multicohort analysis of the contribution of var expression and parasite biomass to severe malaria in two previously published pediatric cohorts in Tanzania and Malawi and an adult cohort in India. Machine learning analysis revealed independent and complementary roles for var adhesion types and parasite biomass in adult and pediatric severe malaria and showed that similar var profiles, including upregulation of group A and DC8 var, predict severe malaria in adults and children. Among adults, patients with multiorgan complications presented infections with significantly higher parasite biomass without significant differences in var adhesion types. Conversely, pediatric patients with specific complications showed distinct var signatures. Cerebral malaria patients showed broadly increased expression of var genes, in particular group A and DC8 var, while children with severe malaria anemia were classified based on high transcription of DC8 var only. This study represents the first large multisite meta-analysis of var expression, and it demonstrates the presence of common var profiles in severe malaria patients of different ages across distant geographical sites, as well as syndrome-specific disease signatures. The complex associations between parasite biomass, var adhesion type, and clinical presentation revealed here represent the most comprehensive picture so far of the relationship between cytoadhesion, parasite load, and clinical syndrome.IMPORTANCEP. falciparum malaria can cause multiple disease complications that differ by patient age. Previous studies have attempted to address the roles of parasite adhesion and biomass in disease severity; however, these studies have been limited to single geographical sites, and there is limited understanding of how parasite adhesion and biomass interact to influence disease manifestations. In this meta-analysis, we compared parasite disease determinants in African children and Indian adults. This study demonstrates that parasite biomass and specific subsets of var genes are independently associated with detrimental outcomes in both childhood and adult malaria. We also explored how parasite var adhesion types and biomass play different roles in the development of specific severe malaria pathologies, including childhood cerebral malaria and multiorgan complications in adults. This work represents the largest study to date of the role of both var adhesion types and biomass in severe malaria.

Impaired NK cell functionality and increased TNF-α production as biomarkers of chronic chikungunya arthritis and rheumatoid arthritis.

The chronic chikungunya arthritis symptoms closely mimic the rheumatoid arthritis (RA) symptoms, thus making it difficult to distinguish between these two clinical entities. The current comparative study characterizes NK (CD3-CD56+) and NK-like T (CD3+CD56+) cell responses in patients with chronic chikungunya arthritis and RA. Phenotype and functions of NK and NK-like T cells repertoire were assessed in 56 chronic chikungunya arthritis, 26 RA patients and 82 controls using flow cytometry. TNF-α and IFN-γ-secreting NK-like T cells were high in both chronic arthritis patients than in controls. Percentage of TNF-α+ NK cells was higher in RA patients than in controls. Percentage of perforin+ NK cells was low in both chronic arthritis patient groups. Among the patient groups, expressions of perforin+ and IFN-γ+ NK-like T cells were higher in RA. Overall, our data show reduced frequency of NK-like T cells, lower expression of perforin+ NK, higher expression of TNF-α+ NK-like T and IFN-γ+ NK-like T cells as the markers of chronic arthritic diseases. In the absence of any specific treatment for chronic chikungunya induced arthritis and promising results of anti-TNF-α therapy against RA, current data may form the basis for future in vivo studies and has scope as possible therapeutics against chikungunya.

Demographic and clinical profiles of Plasmodium falciparum and Plasmodium vivax patients at a tertiary care centre in southwestern India.

BACKGROUND: Malaria remains an important cause of morbidity and mortality in India. Though many comprehensive studies have been carried out in Africa and Southeast Asia to characterize and examine determinants of Plasmodium falciparum and Plasmodium vivax malaria pathogenesis, fewer have been conducted in India. METHODS: A prospective study of malaria-positive individuals was conducted at Goa Medical College and Hospital (GMC) from 2012 to 2015 to identify demographic, diagnostic and clinical indicators associated with P. falciparum and P. vivax infection on univariate analysis. RESULTS: Between 2012 and 2015, 74,571 febrile individuals, 6287 (8.4%) of whom were malaria positive, presented to GMC. The total number of malaria cases at GMC increased more than two-fold over four years, with both P. vivax and P. falciparum cases present year-round. Some 1116 malaria-positive individuals (mean age = 27, 91% male), 88.2% of whom were born outside of Goa and 51% of whom were construction workers, were enroled in the study. Of 1088 confirmed malaria-positive patients, 77.0% had P. vivax, 21.0% had P. falciparum and 2.0% had mixed malaria. Patients over 40 years of age and with P. falciparum infection were significantly (p < 0.001) more likely to be hospitalised than younger and P. vivax patients, respectively. While approximately equal percentages of hospitalised P. falciparum (76.6%) and P. vivax (78.9%) cases presented with at least one WHO severity indicator, a greater percentage of P. falciparum inpatients presented with at least two (43.9%, p < 0.05) and at least three (29.9%, p < 0.01) severity features. There were six deaths among the 182 hospitalised malaria positive patients, all of whom had P. falciparum. CONCLUSION: During the four year study period at GMC, the number of malaria cases increased substantially and the greatest burden of severe disease was contributed by P. falciparum.

An insertion in the methyltransferase domain of P. falciparum trimethylguanosine synthase harbors a classical nuclear localization signal.

Many Plasmodium falciparum proteins do not share homology with, and are generally longer than their respective orthologs. This, to some extent, can be attributed to insertions. Here, we studied a P. falciparum RNA hypermethylase, trimethylguanosine synthase (PfTGS1) that harbors a 76 amino acid insertion in its methyltransferase domain. Bioinformatics analysis revealed that this insertion was present in TGS1 orthologs from other Plasmodium species as well. Interestingly, a classical nuclear localization signal (NLS) was predicted in the insertions of primate parasite TGS1 proteins. To check whether these predicted NLS are functional, we developed an in vivo heterologous system using S. cerevisiae. The predicted NLS when fused to dimeric GFP were able to localize the fusion protein to the nucleus in yeast indicating that it is indeed recognized by the yeast nuclear import machinery. We further showed that the PfTGS1 NLS binds to P. falciparum importin-α in vitro, confirming that the NLS is also recognized by the P. falciparum classical nuclear import machinery. Thus, in this study we report a novel function of the insertion in PfTGS1.

Severe adult malaria is associated with specific PfEMP1 adhesion types and high parasite biomass.

The interplay between cellular and molecular determinants that lead to severe malaria in adults is unexplored. Here, we analyzed parasite virulence factors in an infected adult population in India and investigated whether severe malaria isolates impair endothelial protein C receptor (EPCR), a protein involved in coagulation and endothelial barrier permeability. Severe malaria isolates overexpressed specific members of the Plasmodium falciparum var gene/PfEMP1 (P. falciparum erythrocyte membrane protein 1) family that bind EPCR, including DC8 var genes that have previously been linked to severe pediatric malaria. Machine learning analysis revealed that DC6- and DC8-encoding var transcripts in combination with high parasite biomass were the strongest indicators of patient hospitalization and disease severity. We found that DC8 CIDRα1 domains from severe malaria isolates had substantial differences in EPCR binding affinity and blockade activity for its ligand activated protein C. Additionally, even a low level of inhibition exhibited by domains from two cerebral malaria isolates was sufficient to interfere with activated protein C-barrier protective activities in human brain endothelial cells. Our findings demonstrate an interplay between parasite biomass and specific PfEMP1 adhesion types in the development of adult severe malaria, and indicate that low impairment of EPCR function may contribute to parasite virulence.

5' and 3' end modifications of spliceosomal RNAs in Plasmodium falciparum.

5' caps provide recognition sequences for the nuclear import of snRNAs. The 5' and 3' ends of snRNAs were studied in Plasmodium falciparum with a modified adapter ligation method, which showed that 5' ends of U1, U2, U4, U5 and U6 snRNAs are capped. In P. falciparum, the 3' ends of U1, U2, U4 and U5 snRNAs have free hydroxyl groups whereas U6 snRNA has a blocked 3' end. An immunoprecipitation assay for trimethyl guanosine caps shows that the cap structures of parasite U1-U5 snRNAs are hypermethylated while U6 snRNA may be gamma-mono-methylated. Bioinformatics analysis of proteins involved in hypermethylation and trafficking of snRNAs indicates that the methyltransferase TGS1 is present in the P. falciparum genome. PfTGS1 is larger than its orthologs and may have transmembrane domains in the C-terminus. Surprisingly, the snRNA trafficking protein Snurportin is absent from the P. falciparum genome suggesting that reminiscent of yeast, parasite snRNAs may be retained in the nucleus.