Thermal stability of diagnostic targets plasmodium falciparum histidine rich protein II and plasmodium lactate dehydrogenase in rapid detection.

During the COVID-19 epidemic, blood samples are usually processed at 56 to attenuate the virus before pathogen detection. 71 blood samples of malaria patients reported by Shanghai Center for Disease Control and Prevention in 2017-2019 were collected, including 38 with Plasmodium falciparum infection, 8 P. malariae, 11 P. ovale and 14 P. vivax. The effect of inactivation on the thermal stability of P. falciparum histidine rich protein II (PfHRPII) and Plasmodium lactate dehydrogenase (pLDH) in blood samples was assessed before and after incubation at 56 for 30 min using the rapid diagnostic test (RDT) kit. The results showed that among the 38 P. falciparum T1-positive (PfHRPII) blood samples before heat treatment, 35 samples remained to be T1-positive (92.11%, 35/38, chi2=3.123, P>0.05) after heat treatment;while 54 blood samples (26 P. falciparum, 6 P. vivax, 10 P. ovale and 12 P. vivax) that were T2-positive (pLDH) before heat treatment turned to be T2-negative (positive rate 0, 0/54, chi2=87.755, P<0.01) after heat treatment. It was demonstrated that PfHRPII is stable during incubation at 56 for 30 min, while pLDH is unstable and degraded or inactivated during the heating. Therefore, the detection results of P. falciparum will not be affected by RDT, but diagnosis of the parasites other than P. falciparum in blood samples may be missed.Copyright © 2021, National Institute of Parasitic Diseases. All rights reserved.

The Effect of FOXP3+Regulatory T Cells on Infectious and Inflammatory Diseases

CD4+CD25+FOXP3+regulatory T cells (Tregs) contribute to the maintenance of immune homeostasis and tolerance in the body. The expression levels and functional stability of FOXP3 control the function and plasticity of Tregs. Tregs critically impact infectious diseases, especially by regulating the threshold of immune responses to pathogenic microorganisms. The functional regulatory mechanism and cell-specific surface markers of Tregs in different tissues and inflammatory microenvironments have been investigated in depth, which can provide novel ideas and strategies for immunotherapies targeting infectious diseases.Copyright © 2021. All rights reserved.

Imported malaria from land bordering countries in China: A challenge in preventing the reestablishment of malaria transmission.

OBJECTIVE: No indigenous malaria cases have been reported since 2017 in China, but a large number of imported cases are still reported every year, including those from the land bordering countries. To characterize their epidemiological profiles will provide evidence for the development of appropriate strategies to effectively address the challenges of border malaria in the post-elimination phase. METHODS: Individual-level data of imported malaria cases from the land bordering countries were collected from 2017 to 2021 in China via the web-based surveillance systems, and analyzed by SPSS, ArcGIS and WPS software, to explore their epidemiological profiles. RESULTS: A total of 1170 malaria cases imported into China from six of the fourteen land bordering countries were reported between 2017 and 2021 with a decline trend. Overall, cases were widely distributed in 31-97 counties from 11 to 21 provinces but mainly in Yunnan. Moreover, these imported cases were mainly infected with P. vivax (94.8%), and a total of 68 recurrent cases were reported in 6-14 counties from 4 to 8 provinces. In addition, nearly 57.1% of the total reported cases could seek healthcare within 2 days of getting sick, and 71.3% of the reported cases could be confirmed as malaria on the day they sought medical care. CONCLUSIONS: China still needs to attach great importance to the risk and challenge of the imported malaria from bordering countries particularly from Myanmar in preventing reestablishment of malaria transmission in the post-elimination phase. It is necessary not only to strengthen collaboration and cooperation with the bordering countries, but also coordinate multiple departments at home to improve malaria surveillance and response system and prevent the reestablishment of malaria transmission in China.

Covid-19 in Patients Presenting with Malaria-Like Symptoms at the Korle Bu Polyclinic, Accra

Intro: Malaria is one of Ghana's most frequent illnesses and the most common cause of febrile sickness. Most infectious diseases including COVID-19 and arboviral infections mimic malaria due to the overlapping of non-specific symptoms they both share.This study investigated COVID-19 in patients presenting with malaria-like symptoms at the Korle Bu Polyclinic, Accra. Method(s): This study enrolled 300 patients presenting with malaria-like symptoms aged <= 18. After consent was obtained from study patients, two to three millilitres of whole blood, nasopharyngeal and oropharyngeal swab samples was collected for screening of Plasmodium falciparum using malaria rapid diagnostic test, microscopy and nested PCR and SARS-CoV-2 using SARSCoV-2 antigen test and Real-time PCR respectively. The whole blood sample was also used for COVID-19 antibody test and full blood count using hematological analyser. Finding(s): The detection of SARS-CoV-2 by COVID-19 Rapid Antigen Test and Real-time PCR were 60/300 (20%) and 26/300 (8.7%) respectively. Delta variant was reported in most SARS-CoV-2 positives with CT values below 30. The prevalence of malaria by microscopy, RDT and nested PCR were 7/300 (2.3%), 7/300 (2.3%) and 8/300 (2.7%) respectively. The most common symptom experienced by the study patients at the polyclinic was headache (95%;57/60). Comorbidities reported were hypertension, diabetes, Asthma, hypertension and diabetes. Most of the study patients had been previously exposure to SARS CoV-2 (113/300) and 66.7% (34/51) of AstraZeneca vaccinated patients had no antibody. Conclusion(s): Due to the synergy of symptoms, screening for COVID-19 in patients presenting with malaria-like symptoms is vital for immediate diagnosis and treatment.Copyright © 2023

Molecular genetics and genomics of the ABO blood group system

The A and B oligosaccharide antigens of the ABO blood group system are produced from the common precursor, H substance, by enzymatic reactions catalyzed by A and B glycosyltransferases (AT and BT) encoded by functional A and B alleles at the ABO genetic locus, respectively. In 1990, my research team cloned human A, B, and O allelic cDNAs. We then demonstrated this central dogma of ABO and opened a new era of molecular genetics. We identified four amino acid substitutions between AT and BT and inactivating mutations in the O alleles, clarifying the allelic basis of ABO. We became the first to achieve successful ABO genotyping, discriminating between AA and AO genotypes and between BB and BO, which was impossible using immunohematological/serological methods. We also identified mutations in several subgroup alleles and also in the cis-AB and B(A) alleles that specify the expression of the A and B antigens by single alleles. Later, other scientists interested in the ABO system characterized many additional ABO alleles. However, the situation has changed drastically in the last decade, due to rapid advances in next-generation sequencing (NGS) technology, which has allowed the sequencing of several thousand genes and even the entire genome in individual experiments. Genome sequencing has revealed not only the exome but also transcription/translation regulatory elements. RNA sequencing determines which genes and spliced transcripts are expressed. Because more than 500,000 human genomes have been sequenced and deposited in sequence databases, bioinformaticians can retrieve and analyze this data without generating it. Now, in this era of genomics, we can harness the vast sequence information to unravel the molecular mechanisms responsible for important biological phenomena associated with the ABO polymorphism. Two examples are presented in this review: the delineation of the ABO gene evolution in a variety of species and the association of single nucleotide variant (SNV) sites in the ABO gene with diseases and biological parameters through genome-wide association studies (GWAS).Copyright © Annals of Blood. All rights reserved.

A pitfall of cognitive bias during the pandemic: Two cases of Plasmodium falciparum malaria coinfected or misdiagnosed with COVID-19.

We report two the cases of patients with imported Plasmodium falciparum malaria during the COVID-19 pandemic. One was coinfected with COVID-19 and the other was misdiagnosed with COVID-19; either way, the diagnosis of malaria was delayed. These cases suggest that physicians should beware of cognitive biases during pandemics and carefully evaluate febrile patients. Malaria should be considered in any febrile patient returning from a malaria-endemic area.

A Surge in Malaria Cases in the Eastern Health Region of Saudi Arabia During the COVID-19 Pandemic.

Background Malaria transmission was stopped on most of the vast area of the Kingdom of Saudi Arabia. However, the pandemic of coronavirus disease (COVID-19) has negatively affected the efforts to control malaria. For instance, COVID-19 was reported to induce a relapse of malaria that is caused by Plasmodium vivax. Furthermore, physicians' attention toward COVID-19 can only result in neglect and delayed diagnosis of complicated malaria cases. These factors, among others, might have contributed to an increase of malaria cases in Dammam, Saudi Arabia. Thus, this study was conducted to examine the effects of COVID-19 on malarial cases. Methods The medical records of all patients who were treated at Dammam Medical Complex for malaria between July 1, 2018, and June 30, 2022, were reviewed. Malaria cases were compared between the pre-COVID-19 period (between July 1, 2018, and June 30, 2020) and the COVID-19 period (between July 1, 2020, and June 30, 2022). Results A total of 92 malaria cases occurred in the total study period. There were 60 cases of malaria in the COVID-19 period as opposed to only 32 cases in the pre-COVID-19 period. All the cases were imported from the endemic Saudi southern areas or from outside the country. Eighty-two patients (89.1%) were males. Most of them were Sundaneses (39 patients, 42.4%), Saudis (21 patients, 22.8%), and tribal peoples (14 patients, 15.2%). Fifty-four patients (58.7%) were infected with Plasmodium falciparum. Seventeen patients (18.5%) were infected with Plasmodium vivax. Another 17 patients (18.5%) had a mixed infection with both Plasmodium falciparum and Plasmodium vivax. A trend toward more infected stateless tribal patients was observed in the COVID-19 period compared to the pre-COVID-19 period (21.7% vs 3.1%). A similar trend was noticed for mixed malarial infections with both Plasmodium falciparum and Plasmodium vivax (29.8% vs 0%) with a P value of less than 0.01. Conclusion Malaria cases were almost doubled during the COVID-19 pandemic as compared to the pre-pandemic era signifying the negative effects of the pandemic on malaria epidemiology. The cases increased for a variety of causes that include alternation of health-seeking behaviors, changes in healthcare structures and regulations, and the interruption of malaria preventive services. Future research is needed to study the long-term effects of the changes imposed by the COVID-19 pandemic and to mitigate the effects of any future pandemic on malaria control. As two patients from our cohort were diagnosed with malaria based on blood smears, although they had negative rapid detection tests (RDTs), we recommend testing all the patients who are suspected to have malaria with both RDTs and peripheral blood smears.

Recent Advances in Imported Malaria Pathogenesis, Diagnosis, and Management.

Purpose of Review: Malaria is an important human parasitic disease affecting the population of tropical, subtropical regions as well as travelers to these areas.The purpose of this article is to provide clinicians practicing in non-endemic areas with a comprehensive overview of the recent data on microbiologic and pathophysiologic features of five Plasmodium parasites, clinical presentation of uncomplicated and severe cases, modern diagnostic methods, and treatment of malaria. Recent Findings: Employment of robust surveillance programs, rapid diagnostic tests, highly active artemisinin-based therapy, and the first malaria vaccine have led to decline in malaria incidence; however, emerging drug resistance, disruptions due to the COVID-19 pandemic, and other socio-economic factors have stalled the progress. Summary: Clinicians practicing in non-endemic areas such as the United States should consider a diagnosis of malaria in returning travelers presenting with fever, utilize rapid diagnostic tests if available at their practice locations in addition to microscopy, and timely initiate guideline-directed management as delays in treatment can lead to poor clinical outcomes.

An imported case of ovale malaria in Xinjiang during the epidemic period of COVID-19.

On December 13, 2020, Yutian County People's hospital reported one imported malaria case in Hotan, Xinjiang. The patient had worked and lived in Yaounde, Cameroon, from January to September 2020. He was infected with malaria twice in March and May 2020. Antimalarial treatment was administrated by the team doctor for 2-3 days in each treatment. The treatment was stopped after the symptoms improved. The patient returned to China on September 16 and was hospitalized on December 13 due to a high fever of 39! and upper respiratory symptoms. Multiple detections of COVID-19 nucleic acid showed negative results. Peripheral blood from the patient was taken for Plasmodium rapid diagnostic test (RDT), which showed a positive result suggesting non Plasmodium falciparum infection. Ring stage P. ovale was found in the blood smear. Nested PCR showed positive for P. ovale. A diagnosis of imported ovale malaria was made. The patient was administrated with 4 dihydroartemisinin piperaquine tablets and 3 primaquine phosphate tablets daily. The malaria parasite test became negative after 8 days of treatment. The patient was followed up for 3 months after discharge and had no symptoms of chills or fever.Copyright © 2022, National Institute of Parasitic Diseases. All rights reserved.

Blackwater Fever Treated with Steroids in Nonimmune Patient, Italy.

Causes of blackwater fever, a complication of malaria treatment, are not completely clear, and immune mechanisms might be involved. Clinical management is not standardized. We describe an episode of blackwater fever in a nonimmune 12-year-old girl in Italy who was treated with steroids, resulting in a rapid clinical resolution.

Clinical evaluation of commercial SARS-CoV-2 serological assays in a malaria endemic setting.

The levels of immune response to SARS-CoV-2 infection or vaccination are poorly understood in African populations and is complicated by cross-reactivity to endemic pathogens as well as differences in host responsiveness. To begin to determine the best approach to minimize false positive antibody levels to SARS-CoV-2 in an African population, we evaluated three commercial assays, namely Bio-Rad Platelia SARS-CoV-2 Total Antibody (Platelia), Quanterix Simoa Semi-Quantitative SARS-CoV-2 IgG Antibody Test (anti-Spike), and the GenScript cPass™ SARS-CoV-2 Neutralization Antibody Detection Kit (cPass) using samples collected in Mali in West Africa prior to the emergence of SARS-CoV-2. A total of one hundred samples were assayed. The samples were categorized in two groups based on the presence or absence of clinical malaria. Overall, thirteen out of one hundred (13/100) samples were false positives with the Bio-Rad Platelia assay and one of the same one hundred (1/100) was a false positive with the anti-Spike IgG Quanterix assay. None of the samples tested with the GenScript cPass assay were positive. False positives were more common in the clinical malaria group, 10/50 (20%) vs. the non-malaria group 3/50 (6%); p = 0.0374 using the Bio-Rad Platelia assay. Association between false positive results and parasitemia by Bio-Rad remained evident, after adjusting for age and sex in multivariate analyses. In summary, the impact of clinical malaria on assay performance appears to depend on the assay and/or antigen being used. A careful evaluation of any given assay in the local context is a prerequisite for reliable serological assessment of anti-SARS-CoV-2 humoral immunity.

A clinical case of coinfection of COVID-19 and tropical malaria.

The global outbreak of the new coronavirus infection COVID-19 is still ongoing, leading to coinfections such as malaria and COVID-19 and others. As evidenced, by the increase in various reports of coinfections. In recent years, Uzbekistan has achieved epidemiological stability for malaria and in 2018 received, an official World Health Organization certificate confirming the country's "malaria-free" status. At the present stage during the COVID-19 pandemic, imported, malaria from abroad, is relevant for our republic and, therefore, there is a constant danger of renewed, transmission, from imported cases. In this article presented the clinical case of coinfection, of COVID-19 and. malaria in a patient. From, the epidemiological data, the patient was a citizen of Cameroon. During treatment of coronavirus infection, the patient noted intermittent chills all over the body and sweating, clinical symptoms of tropical malaria began to appear. Microscopy of a thick drop and. a thin blood, smear confirmed, the presence of Pl. falciparum.. The patient was prescribed, antimalarial therapy with mefloquine, resulting in clinical recovery.Copyright © 2022 Authors. All rights reserved.

Summary of global surveillance data of infectious diseases in January 2023

In January 2023, a total of 64 infectious diseases were reported globally, affecting 235 countries and regions. Except for influenza, the top five infectious diseases affecting greatest number of countries and regions were COVID-19 (235), monkeypox (110), dengue fever (31), measles (27) and cholera (15). The top five infectious diseases with highest case fatality rates were Nipah virus disease (62.5%), Ebola virus disease (47.0%), Crimean-Congo haemorrhagic fever (37.5%), Lassa fever (15.1%) and West Nile fever (7.6%). The top five infectious diseases with greatest number of deaths were COVID-19, malaria, cholera, measles and dengue fever. The prevalent infectious diseases in Asia were COVID-19, cholera and dengue fever, the prevalent infectious diseases in Africa were COVID-19, cholera, yellow fever, Lassa fever, malaria and monkeypox, the prevalent infectious diseases in America were COVID-19, cholera, monkeypox, dengue fever and chikungunya fever, the prevalent infectious disease in Europe were COVID-19, monkeypox and invasive group A streptococcus infection.

Whole sporozoite immunization with Plasmodium falciparum strain NF135 in a randomized trial.

BACKGROUND: Whole sporozoite immunization under chemoprophylaxis (CPS regime) induces long-lasting sterile homologous protection in the controlled human malaria infection model using Plasmodium falciparum strain NF54. The relative proficiency of liver-stage parasite development may be an important factor determining immunization efficacy. Previous studies show that Plasmodium falciparum strain NF135 produces relatively high numbers of large liver-stage schizonts in vitro. Here, we evaluate this strain for use in CPS immunization regimes. METHODS: In a partially randomized, open-label study conducted at the Radboudumc, Nijmegen, the Netherlands, healthy, malaria-naïve adults were immunized by three rounds of fifteen or five NF135-infected mosquito bites under mefloquine prophylaxis (cohort A) or fifteen NF135-infected mosquito bites and presumptive treatment with artemether/lumefantrine (cohort B). Cohort A participants were exposed to a homologous challenge 19 weeks after immunization. The primary objective of the study was to evaluate the safety and tolerability of CPS immunizations with NF135. RESULTS: Relatively high liver-to-blood inocula were observed during immunization with NF135 in both cohorts. Eighteen of 30 (60%) high-dose participants and 3/10 (30%) low-dose participants experienced grade 3 adverse events 7 to 21 days following their first immunization. All cohort A participants and two participants in cohort B developed breakthrough blood-stage malaria infections during immunizations requiring rescue treatment. The resulting compromised immunizations induced modest sterile protection against homologous challenge in cohort A (5/17; 29%). CONCLUSIONS: These CPS regimes using NF135 were relatively poorly tolerated and frequently required rescue treatment, thereby compromising immunization efficiency and protective efficacy. Consequently, the full potential of NF135 sporozoites for induction of immune protection remains inconclusive. Nonetheless, the high liver-stage burden achieved by this strain highlights it as an interesting potential candidate for novel whole sporozoite immunization approaches. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov under identifier NCT03813108.

Association between Rhesus Blood Groups and Malaria Infection: A Systematic Review and Meta-Analysis.

In the literature, there was inconsistency in the risk of malaria between individuals with Rhesus blood group positive (Rh+) and negative (Rh-). The systematic review aimed to investigate the risk of malaria among participants with different Rh blood types. All observational studies that reported the occurrence of Plasmodium infection and investigation of the Rh blood group were searched in five databases (Scopus, EMBASE, MEDLINE, PubMed, and Ovid). Strengthening the Reporting of Observational Studies in Epidemiology was used to assess the reporting quality in the included studies. A random-effects model was used to calculate the pooled log OR and 95% confidence intervals (CIs). Database searches yielded a total of 879 articles, of which 36 were eligible for inclusion in the systematic review. The majority of the included studies (44.4%) revealed that Rh+ individuals had a lower proportion of malaria than Rh- individuals; however, the remaining studies revealed a higher or no difference in the proportion of malaria between Rh+ and Rh- individuals. Overall, with moderate heterogeneity, the pooled results showed no difference in malaria risk between patients with Rh+ and Rh- (p = 0.85, pooled log OR: 0.02, 95% CI: -0.20-0.25, I2: 65.1%, 32 studies). The current study found no link between the Rh blood group and malaria, even though there was a moderate amount of heterogeneity. Further studies using prospective designs and a definitive method for Plasmodium identification are needed to investigate the risk of Plasmodium infection in Rh+ individuals and increase the reliability and quality of these studies.

First molecular documented case of a rarely reported parasite: Plasmodium knowlesi infection in Denmark in a traveller returning from Malaysian Borneo.

Plasmodium knowlesi has been reported as an emerging infection throughout the Southeast Asian region, especially in the Malaysian state of Sabah, where it accounts for the majority of the malaria cases reported. This is in contrast to Europe, where imported P. knowlesi is a rarely reported infection. We present a case of P. knowlesi infection in a Danish woman returning from a short trip to Malaysian Borneo. Microscopy of blood smears revealed 0.8% infected erythrocytes, but due to the atypical morphological presentation, a conclusive species identification was made by molecular methods. Plasmodium knowlesi is a potentially fatal infection and taking the increasing travel activity into consideration after the coronavirus disease 2019 (COVID-19) pandemic, P. knowlesi should be a differential diagnosis in patients with travel-associated illness returning from highly endemic Southeast Asian areas.

Clinical performance evaluation of an anti-SARS-CoV-2 IgG enzyme-linked immunosorbent assay

Background: The coronavirus disease 2019 (COVID-19) pandemic continues to cause widespread disruption to daily life globally. With increasing levels of vaccination and the emergence of new variants, it is important to monitor and identify individuals who have produced an immune response to SARS-CoV-2 and those who may remain at higher risk. Aims & Objectives: This study aimed to evaluate the clinical performance of a serological anti-SARS-CoV-2 Immunoglobulin G (IgG) Enzyme-Linked Immunosorbent Assay (ELISA), initially created by AstraZeneca and further developed and validated by ProAxsis Ltd. Method(s): The ProAxsis ELISA was used to assess anti-SARS-CoV-2 IgG levels in 402 positive and 701 negative plasma samples. Samples from each of the SARS-CoV-2 genetic variants (alpha, delta and omicron), along with the World Health Organisation International Reference Panel (NIBSC:20/268) and a panel of seroconversion samples were also tested. Result(s): Sensitivity and specificity of the ProAxsis Anti-SARS-CoV-2 IgG ELISA was 100.0% (CI 95% = 99.1- 100.0%) and 99.3% (CI 95% = 98.3-99.8%) respectively. The ProAxsis and comparator test (Euroimmun) were in almost perfect agreement, Cohen's Kappa (kappa) = 0.991 (CI 95% = 0.982-0.999, p<0.0001). Seroconversion was observed with the ProAxsis ELISA at an earlier stage than with the comparator assay. Of the 101 virology samples tested only one sample (Anti-malaria plasma P.falciparum) displayed some cross-reactivity. Conclusion(s): The ProAxsis Anti-SARS-CoV-2 IgG ELISA demonstrated excellent clinical performance in comparison to a comparator assay and will be highly useful in identifying individuals who have raised antibodies following exposure to SARS-CoV-2 or vaccination.

Summary of global surveillance data of infectious diseases in December 2022

In December 2022, a total of 68 infectious diseases were reported globally, affecting 235 countries and regions. Except for influenza, the top five infectious diseases affecting greatest number of countries and regions were COVID-19 (235), monkeypox (110), dengue fever (28), measles (27) and cholera (14). The top five infectious diseases with highest case fatality rates were Ebola virus disease (47.0%), Rift Valley fever (44.2%), Crimean-Congo haemorrhagic fever (40.0%), Lassa fever (17.6%) and West Nile fever (7.6%). The top five infectious diseases with greatest number of deaths were COVID-19, malaria, cholera, dengue fever and measles. The prevalent infectious diseases in Asia were COVID-19, cholera and dengue fever, the prevalent infectious diseases in Africa were COVID-19, cholera, yellow fever, Lassa fever, monkeypox, malaria and measles, the prevalent infectious diseases in America were COVID-19, cholera, monkeypox, dengue fever and chikungunya fever, the prevalent infectious disease in Europe were COVID-19, monkeypox and invasive group A streptococcus infection.