ABSTRACT
BACKGROUND: Malaria-endemic areas are not spared from the impact of coronavirus disease 2019 (COVID-19), leading to co-infection scenarios where overlapping symptoms impose serious diagnostic challenges. Current knowledge on Plasmodium spp. and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) co-infection in pregnant women remains limited, especially in Latin America, where Plasmodium vivax infection is highly prevalent. METHODS: This is a case series of five pregnant women with P. vivax and SARS-CoV-2 co-infection hospitalized in two main malaria referral centers of the Capital District and Bolivar state, Venezuela between March 13, 2020 and December 31, 2021. RESULTS: Clinical and laboratory data from five pregnant women with a mean age of 22 years were analyzed; three of them were in the third trimester of pregnancy. Comorbidities included obesity in two cases, hypertension in one, and asthma in one. Three out of five patients had severe to critical COVID-19 disease. Dry cough, fever, chills, and headache were the most frequent symptoms reported. Laboratory analyses showed elevated aspartate/alanine aminotransferase and creatinine levels, thrombocytopenia, and severe anemia as the most relevant abnormalities. The mean period between symptom onset and a positive molecular test for SARS-CoV-2 infection or positive microscopy for Plasmodium spp. was 4.8 ± 2.5 days and 2.8 ± 1.6 days, respectively. The mean hospital stay was 5.4 ± 7 days. Three women recovered and were discharged from the hospital. Two women died, one from cerebral malaria and one from respiratory failure. Three adverse fetal outcomes were registered, two miscarriages and one stillbirth. CONCLUSION: This study documented a predominance of severe/critical COVID-19 disease and a high proportion of adverse maternal-fetal outcomes among pregnant women with malaria and COVID-19 co-infection. More comprehensive prospective cohort studies are warranted to explore the risk factors, management challenges, and clinical outcomes of pregnant women with this co-infection.
Subject(s)
Abortion, Spontaneous , COVID-19 , Coinfection , Malaria, Vivax , Malaria , Pregnancy Complications, Infectious , Female , Humans , Pregnancy , Young Adult , Coinfection/diagnosis , Coinfection/epidemiology , COVID-19/diagnosis , COVID-19/epidemiology , Malaria, Vivax/diagnosis , Malaria, Vivax/epidemiology , Plasmodium vivax , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnant Women , Prospective Studies , SARS-CoV-2 , Venezuela/epidemiologyABSTRACT
BACKGROUND: Mucormycosis is a potentially lethal, angioinvasive fungal infection caused by the Mucoracea family comprising Mucor, Rhizopus, and Absidia species. It is commonly associated with uncontrolled diabetes mellitus, the use of corticosteroids, immunosuppressive drugs, and Covid-19 infection. The occurrence of mucormycosis in an immunocompetent patient is rare. Also, only a few case reports have been published where patients developed mucormycosis with associated malarial infection. CASE PRESENTATION: A young female presented with a 3-weeks history of painful swelling and outward protrusion of the right eye with complete loss of vision. She had a history of P.vivax malaria two weeks before her ocular symptoms. On ocular examination, there was proptosis and total ophthalmoplegia with loss of corneal sensations in the right eye. Hematological examination revealed normocytic normochromic anemia and thrombocytopenia. MRI was suggestive of right-sided pansinusitis and orbital cellulitis with right superior ophthalmic vein thrombosis and bulky cavernous sinus. Nasal biopsy was negative for fungal culture. An emergency surgical debridement of all the sinuses was done with right orbital exenteration. Histopathology confirmed the diagnosis of mucormycosis and the patient improved post-operatively on systemic antifungals. CONCLUSION: Such an association of mucormycosis with malaria infection is rarely reported in the literature and is hypothesized to be a result of immunosuppression caused by malaria. Also, emphasis is laid upon having a high index of suspicion for fungal infection in the setting of pansinusitis even if the risk factors are absent. We hereby report a case of rhino-orbital mucormycosis following P.vivax malaria in a 20-year-old female with anemia and thrombocytopenia.
Subject(s)
COVID-19 , Eye Infections, Fungal , Malaria, Vivax , Mucormycosis , Orbital Cellulitis , Orbital Diseases , Thrombocytopenia , Adult , Antifungal Agents/therapeutic use , COVID-19/complications , Eye Infections, Fungal/complications , Eye Infections, Fungal/diagnosis , Eye Infections, Fungal/drug therapy , Female , Humans , Malaria, Vivax/complications , Malaria, Vivax/drug therapy , Mucormycosis/complications , Mucormycosis/diagnosis , Mucormycosis/microbiology , Orbital Diseases/complications , Orbital Diseases/diagnosis , Thrombocytopenia/complications , Young AdultABSTRACT
BACKGROUND: Circulating myeloid-derived-suppressor-cells (MDSC) with immunosuppressive function are increased in human experimental Plasmodium falciparum infection, but have not been studied in clinical malaria. METHODS: Using flow-cytometry, circulating polymorphonuclear-MDSC were evaluated in cryopreserved samples from patients with uncomplicated Plasmodium vivax (n = 8) and uncomplicated (n = 4) and severe (n = 16) falciparum malaria from Papua, Indonesia. RESULTS: The absolute number of circulating polymorphonuclear-MDSC were significantly elevated in severe falciparum malaria patients compared to controls (n = 10). Polymorphonuclear-MDSC levels in uncomplicated vivax malaria were also elevated to levels comparable to that seen in severe falciparum malaria. CONCLUSION: Control of expansion of immunosuppressive MDSC may be important for development of effective immune responses in falciparum and vivax malaria.
Subject(s)
Malaria, Falciparum , Malaria, Vivax , Malaria , Myeloid-Derived Suppressor Cells , Humans , Indonesia , Malaria/complications , Plasmodium falciparum , Plasmodium vivaxABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) often causes atypical clinical manifestations similar to other infectious diseases. In malaria-endemic areas, the pandemic situation will very likely result in co-infection of COVID-19 and malaria, although reports to date are still few. Meanwhile, this disease will be challenging to diagnose in areas with low malaria prevalence because the symptoms closely resemble COVID-19. CASE PRESENTATION: A 23-year-old male patient presented to the hospital with fever, anosmia, headache, and nausea 1 week before. He was diagnosed with COVID-19 and treated for approximately 10 days, then discharged to continue self-quarantine at home. 2 weeks later, he returned to the hospital with a fever raised intermittently every 2 days and marked by a chilling-fever-sweating cycle. A laboratory test for malaria and a nasopharyngeal swab for SARS CoV-2 PCR were conducted, confirming both diagnoses. The laboratory examination showed markedly elevated D-dimer. He was treated with dihydroartemisinin-piperaquine (DHP) 4 tablets per day for 3 days and primaquine 2 tablets per day for 14 days according to Indonesian National Anti-malarial Treatment Guidelines. After 6 days of treatment, the patient had no complaints, and the results of laboratory tests had improved. This report describes the key points in considering the differential diagnosis and prompt treatment of malaria infection during the pandemic of COVID-19 in an endemic country to prevent the worse clinical outcomes. COVID-19 and malaria may also cause a hypercoagulable state, so a co-infection of those diseases may impact the prognosis of the disease. CONCLUSION: This case report shows that considering the possibility of a co-infection in a COVID-19 patient who presents with fever can prevent delayed treatment that can worsen the disease outcome. Paying more attention to a history of travel to malaria-endemic areas, a history of previous malaria infection, and exploring anamnesis regarding the fever patterns in patients are important points in making a differential diagnosis of malaria infection during the COVID-19 pandemic.
Subject(s)
COVID-19 , Coinfection , Malaria, Vivax , Malaria , Adult , COVID-19/diagnosis , Coinfection/diagnosis , Coinfection/epidemiology , Fever/epidemiology , Humans , Malaria/complications , Malaria/diagnosis , Malaria/drug therapy , Malaria, Vivax/epidemiology , Male , Pandemics , Recurrence , Young AdultABSTRACT
BACKGROUND: Novel antimalarials should be effective across all species of malaria parasites that infect humans, especially the two species that bear the most impact, Plasmodium falciparum and Plasmodium vivax. Protein kinases encoded by pathogens, as well as host kinases required for survival of intracellular pathogens, carry considerable potential as targets for antimalarial intervention (Adderley et al. Trends Parasitol 37:508-524, 2021; Wei et al. Cell Rep Med 2:100423, 2021). To date, no comprehensive P. vivax kinome assembly has been conducted; and the P. falciparum kinome, first assembled in 2004, requires an update. The present study, aimed to fill these gaps, utilises a recently published structurally-validated multiple sequence alignment (MSA) of the human kinome (Modi et al. Sci Rep 9:19790, 2019). This MSA is used as a scaffold to assist the alignment of all protein kinase sequences from P. falciparum and P. vivax, and (where possible) their assignment to specific kinase groups/families. RESULTS: We were able to assign six P. falciparum previously classified as OPK or 'orphans' (i.e. with no clear phylogenetic relation to any of the established ePK groups) to one of the aforementioned ePK groups. Direct phylogenetic comparison established that despite an overall high level of similarity between the P. falciparum and P. vivax kinomes, which will help in selecting targets for intervention, there are differences that may underlie the biological specificities of these species. Furthermore, we highlight a number of Plasmodium kinases that have a surprisingly high level of similarity with their human counterparts and therefore not well suited as targets for drug discovery. CONCLUSIONS: Direct comparison of the kinomes of Homo sapiens, P. falciparum and P. vivax sheds additional light on the previously documented divergence of many P. falciparum and P. vivax kinases from those of their human host. We provide the first direct kinome comparison between the phylogenetically distinct species of P. falciparum and P. vivax, illustrating the key similarities and differences which must be considered in the context of kinase-directed antimalarial drug discovery, and discuss the divergences and similarities between the human and Plasmodium kinomes to inform future searches for selective antimalarial intervention.
Subject(s)
Malaria, Falciparum , Malaria, Vivax , Humans , Malaria, Falciparum/parasitology , Malaria, Vivax/parasitology , Phylogeny , Plasmodium falciparum/genetics , Plasmodium vivax/geneticsABSTRACT
Malaria is the most important vector-borne disease in the world and a challenge for control programs. In Brazil, 99% of cases occur in the Amazon region. In the extra-Amazonian region, a non-endemic area, epidemiological surveillance focuses on imported malaria and on autochthonous outbreaks, including cases with mild symptoms and low parasitemia acquired in the Atlantic Forest biome. In this scenario, cases are likely to be underreported, since submicroscopic parasitemias are not detected by thick blood smear, considered the reference test. Molecular tests are more sensitive, detecting asymptomatic individuals and mixed infections. The aim of this study was to propose a more efficient alternative to detect asymptomatic individuals living in areas of low malaria endemicity, as they are reservoirs of Plasmodium that maintain transmission locally. In total, 955 blood samples from residents of 16 municipalities with autochthonous malaria outbreaks in the Sao Paulo State were analyzed; 371 samples were collected in EDTA tubes and 584 in filter paper. All samples were initially screened by a genus-specific qPCR targeting ssrRNA genes (limit of detection of 1 parasite/µL). Then, positive samples were subjected to a nested PCR targeting ssrRNA and dihydrofolate reductase-thymidylate synthase genes (limit of detection of 10 parasites/µL) to determine Plasmodium species. The results showed a statistically significant difference (K = 0.049; p < 0.0001) between microscopy positivity (6.9%) and qPCR (22.9%) for EDTA-blood samples. Conversely, for samples collected in filter paper, no statistical difference was observed, with 2.6% positivity by thick blood smear and 3.1% for qPCR (K = 0.036; p = 0.7). Samples positive by qPCR were assayed by a species-specific nested PCR that was in turn positive in 26% of samples (16 P. vivax and 4 P. malariae ). The results showed that molecular protocols applied to blood samples from residents in areas with autochthonous transmission of malaria were useful to detect asymptomatic patients who act as a source of transmission. The results showed that the genus-specific qPCR was useful for screening positives, with the subsequent identification of species by nested PCR. Additional improvements, such as standardization of blood plotting on filter paper and a more sensitive protocol for species determination, are essential. The qPCR-based algorithm for screening positives followed by nested PCR will contribute to more efficient control of malaria transmission, offering faster and more sensitive tools to detect asymptomatic Plasmodium reservoirs.
Subject(s)
Malaria, Vivax , Malaria , Plasmodium , Algorithms , Brazil/epidemiology , Ecosystem , Forests , Humans , Malaria/diagnosis , Malaria/epidemiology , Malaria, Vivax/diagnosis , Plasmodium/genetics , Plasmodium vivax/genetics , Real-Time Polymerase Chain ReactionABSTRACT
The conventional paper-based system for malaria surveillance is time-consuming, difficult to track and resource-intensive. Few digital platforms are in use but wide-scale deployment and acceptability remain to be seen. To address this issue, we created a malaria surveillance mobile app that offers real-time data to stakeholders and establishes a centralised data repository. The MoSQuIT app was designed to collect data from the field and was integrated with a web-based platform for data integration and analysis. The MoSQuIT app was deployed on mobile phones of accredited social health activists (ASHA) working in international border villages in the northeast (NE) Indian states of Assam, Tripura and Arunachal Pradesh for 20 months in a phased manner. This paper shares the challenges and opportunities associated with the use of MoSQuIT for malaria surveillance. MoSQuIT employs the same data entry formats as the NVBDCP's malaria surveillance programme. Using this app, a total of 8221 fever cases were recorded, which included 1192 (14.5%) cases of P. falciparum malaria, 280 (3.4%) cases of P. vivax malaria and 52 (0.6%) mixed infection cases. Depending on network availability, GPS coordinates of the fever cases were acquired by the app. The present study demonstrated that mobile-phone-based malaria surveillance facilitates the quick transmission of data from the field to decision makers. Geospatial tagging of cases helped with easy visualisation of the case distribution for the identification of malaria-prone areas and potential outbreaks, especially in hilly and remote regions of Northeast India. However, to achieve the full operational potential of the system, operational challenges have to be overcome.
Subject(s)
Malaria, Falciparum , Malaria, Vivax , Malaria , Mobile Applications , Telemedicine , Fever , Humans , India/epidemiology , Malaria/epidemiology , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiologyABSTRACT
BACKGROUND: Eliminating malaria along the China-Vietnam border remains one of the greatest challenges in China, especially during the coronavirus disease 2019 (COVID-19) pandemic, which has disrupted the continuity of malaria control and elimination programs. Understanding the factors associated with asymptomatic malaria infection will inform control interventions aimed at elimination of the disease among migrants from Vietnam working in China, who constitute an at-risk population. METHODS: From March 2018 to September 2019, 108 migrants from Vietnam working in Ningming County, Guangxi, were enrolled in this study. Each person was interviewed using a structured questionnaire. Blood samples were collected and sent for PCR detection and sequencing. The obtained sequences were analyzed using the BLAST program and DNAMAN software. RESULTS: The proportion of participants with malaria knowledge was low, with 19.4% (21/108) reporting knowledge about transmission, 23.2% (25/108) reporting knowledge about clinical symptoms, 7.4% (8/108) reporting awareness of the risk of death and 14.8% (16/108) reporting awareness of prevention methods. No significant difference in the malaria knowledge rate was found among occupational groups, except in the migrant worker group, whose knowledge rate was higher than those in the other occupational groups (χ2 = 32.452, p < 0.001). Although most of the participants (80.6%, 87/108) owned mosquito nets, only approximately half of the participants (49.1%, 53/108) reported using bed nets. The parasitological analysis revealed that 5.6% (6/108) of all the participants were positive for malaria, including 5 participants with Plasmodium falciparum and 1 participant with Plasmodium vivax malaria. There were no statistically significant differences in the positivity rates among the different age, sex, family-size, nationality, occupational, and behavior groups. The positivity rates in individuals who did not use mosquito nets, did not use mosquito coils, and did not install mosquito nets were 4.8% (1/21), 6.8% (3/44), and 3.6% (2/55), respectively. CONCLUSION: Health education focused on high-risk populations, such as migrant workers and forest goers, should be strengthened. Verbal communication and information transmission via the internet, radio, and mobile phone platforms may be required during the COVID-19 pandemic. Further risk assessments and proactive case detection should also be performed in Ningming County and other border counties in Guangxi to detect active and asymptomatic infections in a timely manner and prevent re-establishment of the disease in these communities.
Subject(s)
COVID-19 , Malaria, Falciparum , Malaria, Vivax , Malaria , Transients and Migrants , Asymptomatic Infections/epidemiology , COVID-19/epidemiology , China/epidemiology , Humans , Malaria/drug therapy , Malaria/epidemiology , Malaria/prevention & control , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Pandemics , Plasmodium vivax , Vietnam/epidemiologyABSTRACT
BACKGROUND: Malaria-associated anaemia, arising from symptomatic, asymptomatic and submicroscopic infections, is a significant cause of morbidity worldwide. Induced blood stage malaria volunteer infection studies (IBSM-VIS) provide a unique opportunity to evaluate the haematological response to early Plasmodium falciparum and Plasmodium vivax infection. METHODS: This study was an analysis of the haemoglobin, red cell counts, and parasitaemia data from 315 participants enrolled in IBSM-VIS between 2012 and 2019, including 269 participants inoculated with the 3D7 strain of P. falciparum (Pf3D7), 15 with an artemisinin-resistant P. falciparum strain (PfK13) and 46 with P. vivax. Factors associated with the fractional fall in haemoglobin (Hb-FF) were evaluated, and the malaria-attributable erythrocyte loss after accounting for phlebotomy-related losses was estimated. The relative contribution of parasitized erythrocytes to the malaria-attributable erythrocyte loss was also estimated. RESULTS: The median peak parasitaemia prior to treatment was 10,277 parasites/ml (IQR 3566-27,815), 71,427 parasites/ml [IQR 33,236-180,213], and 34,840 parasites/ml (IQR 13,302-77,064) in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. The median Hb-FF was 10.3% (IQR 7.8-13.3), 14.8% (IQR 11.8-15.9) and 11.7% (IQR 8.9-14.5) in those inoculated with Pf3D7, PfK13 and P. vivax, respectively, with the haemoglobin nadir occurring a median 12 (IQR 5-21), 15 (IQR 7-22), and 8 (IQR 7-15) days following inoculation. In participants inoculated with P. falciparum, recrudescence was associated with a greater Hb-FF, while in those with P. vivax, the Hb-FF was associated with a higher pre-treatment parasitaemia and later day of anti-malarial treatment. After accounting for phlebotomy-related blood losses, the estimated Hb-FF was 4.1% (IQR 3.1-5.3), 7.2% (IQR 5.8-7.8), and 4.9% (IQR 3.7-6.1) in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. Parasitized erythrocytes were estimated to account for 0.015% (IQR 0.006-0.06), 0.128% (IQR 0.068-0.616) and 0.022% (IQR 0.008-0.082) of the malaria-attributable erythrocyte loss in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. CONCLUSION: Early experimental P. falciparum and P. vivax infection resulted in a small but significant fall in haemoglobin despite parasitaemia only just at the level of microscopic detection. Loss of parasitized erythrocytes accounted for < 0.2% of the total malaria-attributable haemoglobin loss.
Subject(s)
Anemia/drug therapy , Antimalarials/therapeutic use , Erythrocytes/parasitology , Malaria, Falciparum/drug therapy , Malaria, Vivax/drug therapy , Parasitemia/drug therapy , Adult , Anemia/parasitology , Female , Humans , Malaria, Falciparum/complications , Malaria, Falciparum/parasitology , Malaria, Vivax/complications , Malaria, Vivax/parasitology , Male , Middle Aged , Parasitemia/parasitology , Plasmodium falciparum/drug effects , Plasmodium vivax/drug effects , Young AdultABSTRACT
PURPOSE: This population-based open cohort study aims to investigate biological and sociodemographic drivers of malaria transmission in the main urban hotspot of Amazonian Brazil. PARTICIPANTS: Nearly 20% of the households in the northwestern town of Mâncio Lima were randomly selected and 2690 participants were enrolled since April 2018. Sociodemographic, housing quality, occupational, behavioural and morbidity information and travel histories were collected during consecutive study visits. Blood samples from participants>3 months old were used for malaria diagnosis and human genetic studies; samples from participants with laboratory-confirmed malaria have been cryopreserved for genetic and phenotypic characterisation of parasites. Serology was introduced in 2020 to measure the prevalence and longevity of SARS-CoV-2 IgG antibodies. FINDINGS TO DATE: Malaria prevalence rates were low (up to 1.0% for Plasmodium vivax and 0.6% for P. falciparum) during five consecutive cross-sectional surveys between April-May 2018 and October-November 2020; 63% of infections diagnosed by microscopy were asymptomatic. Malaria risk is heterogeneously distributed, with 20% study participants contributing 86% of the overall burden of P. vivax infection. Adult males are at greatest risk of infection and human mobility across the urban-rural interface may contribute to sustained malaria transmission. Local P. vivax parasites are genetically diverse and fragmented into discrete inbred lineages that remain stable across space and time. FUTURE PLANS: Two follow-up visits, with similar study protocols, are planned in 2021. We aim to identify high-risk individuals that fuel onwards malaria transmission and represent a priority target for more intensive and effective control interventions. TRIAL REGISTRATION NUMBER: NCT03689036.
Subject(s)
COVID-19 , Malaria, Falciparum , Malaria, Vivax , Malaria , Adult , Brazil/epidemiology , Cohort Studies , Cross-Sectional Studies , Humans , Infant , Malaria/epidemiology , Malaria, Vivax/epidemiology , Male , Prevalence , SARS-CoV-2ABSTRACT
Background: Coronavirus disease 2019 (COVID-19) often causes atypical clinical manifestations similar to other infectious diseases. In malaria-endemic areas, the pandemic situation will very likely result in co-infection of COVID-19 and Malaria, although reports to date are still few. Meanwhile, in areas with low malaria prevalence, this disease will be challenging to diagnose because the symptoms closely resemble COVID-19.Case presentationA 23-year-old male patient presented to hospital with fever, anosmia, headache, and nausea since one week before. He was diagnosed with COVID-19 and treated for approximately ten days then discharged to continue self-quarantine at home. Two weeks later, he came back to the hospital with fever that was raised intermittently every two days, and was marked by a chilling-fever-sweating cycle. We conducted a laboratory test for malaria and nasopharyngeal swab for SARS CoV-2 PCR which confirmed both of the diagnosis. The laboratory examination showed markedly elevated D-dimer. He was treated with Dihydroartemisinin-Piperaquine (DHP) 4 tablets per day for three days and Primaquine 2 tablets per day for 14 days according to Indonesian national anti-malarial treatment guidelines. After six days of treatment, the patient had no complaints, and the results of laboratory tests had improved. This report describes the key points in considering the differential diagnosis and prompt treatment of malaria infection during the pandemic of COVID-19 in an endemic country to prevent the worse clinical outcomes. COVID-19 and malaria may also cause hypercoagulable state, so a co-infection of those diseases may impact on the prognosis of the disease.ConclusionThis case report shows that considering the possibility of a co-infection in COVID-19 patient who presents with fever can prevent delayed treatment that can worsen the disease outcome. Paying more attention to a history of travel to malaria-endemic areas, a history of previous malaria infection, and exploring anamnesis regarding the fever patterns in patients are important points in making a differential diagnosis of malaria infection during the COVID-19 pandemic.
Subject(s)
Malaria , Fever , Olfaction Disorders , Malaria, Vivax , Communicable Diseases , COVID-19ABSTRACT
AIM: This study is looking for a common pathogenicity between SARS-CoV-2 and Plasmodium species, in individuals with certain HLA serotypes. METHODS: 1. Tblastx searches of SARS-CoV-2 are performed by limiting searches to five Plasmodium species that infect humans. 2. Aligned sequences in the respective organisms' proteomes are searched with blastp. 3. Binding predictions of the identified SARS-CoV-2 peptide to HLA supertype representatives are performed. 4. Blastp searches of predicted epitopes that bind strongly to the identified HLA allele are performed by limiting searches to H. sapiens and Plasmodium species, separately. 5. Peptides with minimum 60% identity to the predicted epitopes are found in results. 6. Peptides among those, which bind strongly to the same HLA allele, are predicted. 7. Step-4 is repeated by limiting searches to H. sapiens, followed by the remaining steps until step-7, for peptides sourced by Plasmodium species after step-6. RESULTS: SARS-CoV-2 peptide with single letter amino acid code CFLGYFCTCYFGLFC has the highest identity to P. vivax. Its YFCTCYFGLF part is predicted to bind strongly to HLA-A*24:02. Peptides in the human proteome both homologous to YFCTCYFGLF and with a strong binding affinity to HLA-A*24:02 are YYCARRFGLF, YYCHCPFGVF, and YYCQQYFFLF. Such peptides in the Plasmodium species' proteomes are FFYTFYFELF, YFVACLFILF, and YFPTITFHLF. The first one belonging to P. falciparum has a homologous peptide (YFYLFSLELF) in the human proteome, which also has a strong binding affinity to the same HLA allele. CONCLUSION: Immune responses to the identified-peptides with similar sequences and strong binding affinities to HLA-A*24:02 can be related to autoimmune response risk in individuals with HLA-A*24:02 serotypes, upon getting infected with SARS-CoV-2 or P. falciparum.
Subject(s)
COVID-19 , HLA-A24 Antigen , Malaria, Vivax , Peptides , Epitopes, T-Lymphocyte , Humans , Peptides/genetics , SARS-CoV-2Subject(s)
Anemia , Malaria, Falciparum , Malaria, Vivax , Autoantibodies , Erythrocytes , Humans , Immunoglobulin G , Immunoglobulin MABSTRACT
Multiplexed bead-based assays that use Luminex® xMAP® technology have become popular for measuring antibodies against proteins of interest in many fields, including malaria and more recently SARS-CoV-2/COVID-19. There are currently two formats that are widely used: non-magnetic beads or magnetic beads. Data are lacking regarding the comparability of results obtained using these two types of beads, and for assays run on different instruments. Whilst non-magnetic beads can only be run on flow-based instruments (such as the Luminex® 100/200™ or Bio-Plex® 200), magnetic beads can be run on both these and the newer MAGPIX® instruments. In this study we utilized a panel of purified recombinant Plasmodium vivax proteins and samples from malaria-endemic areas to measure P. vivax-specific IgG responses using different combinations of beads and instruments. We directly compared: i) non-magnetic versus magnetic beads run on a Bio-Plex® 200, ii) magnetic beads run on the Bio-Plex® 200 versus MAGPIX® and iii) non-magnetic beads run on a Bio-Plex® 200 versus magnetic beads run on the MAGPIX®. We also performed an external comparison of our optimized assay. We observed that IgG antibody responses, measured against our panel of P. vivax proteins, were moderately-strongly correlated in all three of our comparisons (pearson r>0.5 for 18/19 proteins), however higher amounts of protein were required for coupling to magnetic beads. Our external comparison indicated that results generated in different laboratories using the same coupled beads are also highly comparable (pearson r>0.7), particularly if a reference standard curve is used.
Subject(s)
Cell Separation/methods , Immunoglobulin G/immunology , Immunomagnetic Separation/methods , Antigens, Protozoan/immunology , Child , Child, Preschool , Female , Humans , Magnetic Phenomena , Malaria/immunology , Malaria, Vivax/immunology , Male , Microspheres , Papua New Guinea/epidemiology , Plasmodium vivax/immunology , Protozoan Proteins/immunology , TechnologyABSTRACT
Introduction: This aim of the study was to determine prevalence, associated factors, clinical characteristics, virus clearance and treatment outcomes of healthcare workers ( HCWs) with coronavirus disease 2019 (COVID-19) in a dedicated tertiary care COVID-19 hospital in India. Methods: The study included healthcare workers with laboratory confirmed COVID-19 from BYL Nair Hospital (NH), Mumbai, India. The data was captured from medical case records from 6th April to 31st August 2020. Epidemiological data was captured through interview of HCW. Duration of viral clearance amongst symptomatic and symptomatic HWCs was carried out using chi-square test.Results: The prevalence of SARS-CoV2 infection amongst HCWs was observed 11% during the first 5 months of COVID-19 pandemic. Majority of the HCWs with COVID-19 (85%) were symptomatic and 15% were asymptomatic. The frequency of SARS-CoV-2 infection was higher in Male HCWs (57%) as compared to female HCWs (43%). Hypertension and Diabetes Mellitus were the most common co-morbidities reported. More than 4% percent (18/413) of HCWs with COVID-19 were also positive for plasmodium vivax Malaria. 26% (107/413) of HCWs with COVID-19 were having symptoms suggestive of Severe Acute Respiratory Infection (SARI). Median duration for virus clearance was 11 (IQR, 7-15) days with maximum 40 days. Most of the asymptomatic cases cleared the virus within 15 days (93%) whilst most of the symptomatic cases cleared the virus between days 8 to 40 days (73%). Mean time to viral clearance was significantly higher in symptomatic compared to asymptomatic cases (8 days and 12 days, respectively, p<0.0005). Additionally, higher mean time to viral clearance was observed in HCWs with comorbidities as compared to HCWs with co-infection (12 days and 8 days respectively, p<0.0005). There was a significant difference in duration of virus clearance (<7 days) between asymptomatic and symptomatic HCWs (p<0.0005).Around 9% (35/413) of HCWs developed severe disease requiring ICU admission with 1 % mortality. Reinfection of SARS-CoV-2 was reported in 2% of HCWs. Conclusion: There is increased frequency of SARS-CoV-2 infection amongst frontline HCWs. We recommend universal testing of HCWs and double negative testing to label HCWs as fit to discharge to optimize staffing levels during this current pandemic. Testing should also be extended to family members and other close contacts. The HCWs are the most precious resource for every country.