Imported malaria has become a major risk factor for malaria prevention and control in China. How to screen malaria quickly for people entering China is an urgent problem to be solved. Protein microarrays are widely used in high-throughput screening and diagnosis. In this study, surface plasmon resonance (SPR) technique for malaria detection was established by using the specific adsorption surface treated by polyethylene glycol polymer, and the malaria specific antigen HRP2 was used as capture probe. The optimal concentration of antigen, sensitivity and specificity of detection, as well as anti-interference ability of the chip were analyzed. The SPR protein chip was applied to detect specific antibodies of malignant malaria in serum with the advantage of label-free, instant and fast. Compared with fluorescence quantitative PCR, there were no significant difference in sensitivity and specificity between the two methods. This study lays a foundation for further development of protein microarray for malaria typing identification, and it is conducive to the rapid screening of malaria for people entering.
Antibodies ; China ; Humans ; Malaria/diagnosis* ; Protein Array Analysis ; Surface Plasmon Resonance

Rapid diagnostic tests (RDTs) for malaria using antibodies against pan-Plasmodium antigen lactate dehydrogenase (pLDH) are commonly used for malaria diagnosis. The level of malaria parasitemia determined by peripheral blood smears (PBS) correlates with the pLDH concentration in most cases. We report a case of malaria recurrence associated with false-negative RDT results. A 22-year-old male patient was admitted to the Armed Forces Capital Hospital with fever and chills, and was diagnosed with malaria infection. Four days after antimalarial treatment, these symptoms recurred. After admitting to our hospital, doxycycline was administered for 4 days. Even after administration of doxycycline, the malaria parasites in blood smears remained positive, but RDT showed negative results. Therefore, for patients receiving doxycycline, serial blood smear testing should be performed to exclude false-negative malaria RDT results.
Antibodies ; Arm ; Chills ; Diagnosis ; Diagnostic Tests, Routine ; Doxycycline ; Fever ; Humans ; L-Lactate Dehydrogenase ; Malaria ; Male ; Parasitemia ; Parasites ; Recurrence ; Young Adult

Detailed description of malaria in low transmission areas is crucial for elimination. The current study aimed to provide a comprehensive description for malaria transmission in Jazan, a low transmission district, southwestern Saudi Arabia. Patients at a tertiary care hospital were recruited in our study between August 2016 and September 2018. Malaria diagnosis was performed through a species-specific nested polymerase chain reaction (nested PCR), microscopy and Paramax-3™ rapid detection test (RDT). Malaria was detected in 30 patients by the PCR, with point prevalence of 10.9%. Of these malaria infections, 80% was imported, 26.6% was asymptomatic and 23.3% was sub-microscopic. Malaria was reported throughout the year, with February/March and September/October peaks. Infection was significantly more in males than in females (P=0.01). Likewise, infections were detected more in febrile than in non-febrile patients (P=0.01). Adult aged 15–24 years, fever and travel were identified as high-risk factors. Malaria was primarily attributed to Plasmodium falciparum mono-infections, followed by P. vivax mono-infections and lastly to falciparum/vivax mixed infections accounting 76.6%, 16.6%, and 6.6% of PCR-confirmed malaria cases, respectively. The nested PCR was superior to the smear microscopy (sensitivity 76.6%; specificity 100%) and the RDT (sensitivity 83.3%, specificity 94.2%). The overall percent agreement between microscopy and the RDT was 92.7% (kappa=0.63). High proportion of imported malaria including sub-microscopic and sub-patent cases were described. We suggest that incorporation of molecular tool into the conventional malaria diagnosis is beneficial in Jazan district.
Adult ; Coinfection ; Diagnosis ; Female ; Fever ; Humans ; Malaria ; Male ; Microscopy ; Plasmodium falciparum ; Polymerase Chain Reaction ; Prevalence ; Saudi Arabia ; Sensitivity and Specificity ; Tertiary Healthcare

This study aimed to determine the status of common parasitic disease in Korea in 2019. Twelve parasitic diseases were selected: toxocariasis, anisakiasis, paragonimiasis, sparganosis, cysticercosis, toxoplasmosis, clonorchiasis, enterobiasis, trichuriasis, trichomoniasis, cryptosporidiosis, and malaria. Their biology, epidemiology, pathogenesis, symptoms and signs, diagnosis, treatment, and prognosis were evaluated. Of the parasitic diseases, toxocariasis was the most prevalent according to serological results. Anisakiasis should be considered when acute gastrointestinal symptoms occur with a recent past history of raw seafood ingestion. Paragonimiasis, sparganosis, and cysticercosis can be diagnosed using an enzyme-linked immunosorbent assay; thus, enzyme-linked immunosorbent assay needs to be performed for suspected cases. Toxoplasmosis and cryptosporidiosis are opportunistic infections. The symptoms and signs are aggravated under immunocompromised conditions. Although the egg positivity rate of Clonorchis sinensis is higher than that of other intestinal parasitic diseases, encountering patients with complaints of symptoms caused by clonorchiasis is rare because the worm burden is low. Trichomoniasis is usually managed by gynecologists; therefore, it should be included in the differential diagnoses of vaginal diseases. The annual number of malaria cases has decreased, although it remains at approximately 500 cases per year. Malaria should be suspected when symptoms such as intermittent fever, headache, and splenomegaly are noted especially when the patients reside near demilitarized zones. Although the prevalence and number of reported cases of parasitic diseases have decreased in Korea, we should consider parasitic diseases in the list of differential diagnoses.
Animals ; Anisakiasis ; Biology ; Clonorchiasis ; Clonorchis sinensis ; Cryptosporidiosis ; Cysticercosis ; Diagnosis ; Diagnosis, Differential ; Eating ; Enterobiasis ; Enzyme-Linked Immunosorbent Assay ; Epidemiology ; Fever ; Headache ; Humans ; Korea ; Malaria ; Opportunistic Infections ; Ovum ; Paragonimiasis ; Parasitic Diseases ; Prevalence ; Prognosis ; Republic of Korea ; Seafood ; Sparganosis ; Splenomegaly ; Toxocariasis ; Toxoplasmosis ; Trichuriasis ; Vaginal Diseases

Antimalarials ; therapeutic use ; Disease Eradication ; economics ; Humans ; Malaria ; diagnosis ; drug therapy ; prevention & control

The complement is a part of the immune system that plays several roles in removing pathogens. Despite the importance of the complement system, the exact role of each component has been overlooked because the complement system was thought to be a nonspecific humoral immune mechanism that worked against pathogens. Decay-accelerating factor (DAF or CD55) is a known inhibitor of the complement system and has recently attracted substantial attention due to its role in various diseases, such as cancer, protein-losing enteropathy, and malaria. Some protein-losing enteropathy cases are caused by CD55 deficiency, which leads to complement hyperactivation, malabsorption, and angiopathic thrombosis. In addition, CD55 has been reported to be an essential host receptor for infection by the malaria parasite. Moreover, CD55 is a ligand of the seven-span transmembrane receptor CD97. Since CD55 is present in various cells, the functional role of CD55 has been expanded by showing that CD55 is associated with a variety of diseases, including cancer, malaria, protein-losing enteropathy, paroxysmal nocturnal hemoglobinuria, and autoimmune diseases. This review summarizes the current understanding of CD55 and the role of CD55 in these diseases. It also provides insight into the development of novel drugs for the diagnosis and treatment of diseases associated with CD55.
Antigens, CD55 ; Autoimmune Diseases ; Complement System Proteins ; Diagnosis ; Hemoglobinuria, Paroxysmal ; Immune System ; Immunotherapy ; Malaria ; Parasites ; Protein-Losing Enteropathies ; Thrombosis

Molecular techniques have been introduced for malaria diagnosis because they offer greater sensitivity and specificity than microscopic examinations. Therefore, DNA isolation methods have been developed for easy preparation and cost effectiveness. The present study described a simple protocol for Plasmodium DNA isolation from EDTA-whole blood. This study demonstrated that after heating infected blood samples with Tris–EDTA buffer and proteinase K solution, without isolation and purification steps, the supernatant can be used as a DNA template for amplification by PCR. The sensitivity of the extracted DNA of Plasmodium falciparum and Plasmodium vivax was separately analyzed by both PCR and semi-nested PCR (Sn-PCR). The results revealed that for PCR the limit of detection was 40 parasites/μl for P. falciparum and 35.2 parasites/μl for P. vivax, whereas for Sn-PCR the limit of detection was 1.6 parasites/μl for P. falciparum and 1.4 parasites/μl for P. vivax. This new method was then verified by DNA extraction of whole blood from 11 asymptomatic Myanmar migrant workers and analyzed by Sn-PCR. The results revealed that DNA can be extracted from all samples, and there were 2 positive samples for Plasmodium (P. falciparum and P. vivax). Therefore, the protocol can be an alternative method for DNA extraction in laboratories with limited resources and a lack of trained technicians for malaria diagnosis. In addition, this protocol can be applied for subclinical cases, and this will be helpful for epidemiology and control.
Cost-Benefit Analysis ; Diagnosis ; DNA ; Edetic Acid ; Endopeptidase K ; Epidemiology ; Heating ; Hot Temperature ; Humans ; Limit of Detection ; Malaria ; Methods ; Myanmar ; Plasmodium falciparum ; Plasmodium vivax ; Plasmodium ; Polymerase Chain Reaction ; Sensitivity and Specificity ; Transients and Migrants

Prompt diagnosis of malaria cases with rapid diagnostic tests (RDTs) has been widely adopted as an effective malaria diagnostic tool in many malaria endemic countries, primarily due to their easy operation, fast result output, and straightforward interpretation. However, there has been controversy about the diagnostic accuracy of RDTs. This study was conducted to evaluate the diagnostic performances of the 2 commercially available malaria RDT kits, RapiGEN Malaria Ag Pf/Pv (pLDH/pLDH) and Asan EasyTestTM Malaria Ag Pf/Pv (HRP-2/pLDH) for their abilities to detect Plasmodium species in blood samples collected from Ugandan patients with malaria. To evaluate the diagnostic performances of these 2 RDT kits, 229 blood samples were tested for malaria infection by microscopic examination and a species-specific nested polymerase chain reaction. The detection sensitivities for P. falciparum of Malaria Ag Pf/Pv (pLDH/pLDH) and Asan EasyTestTM Malaria Ag Pf/Pv (HRP-2/pLDH) were 87.83% and 89.57%, respectively. The specificities of the 2 RDTs were 100% for P. falciparum and mixed P. falciparum/P. vivax infections. These results suggest that the 2 RDT kits showed reasonable levels of diagnostic performances for detection of the malaria parasites from Ugandan patients. However, neither kit could effectively detect P. falciparum infections with low parasitaemia ( < 500 parasites/μl).
Chungcheongnam-do ; Diagnosis ; Diagnostic Tests, Routine ; Humans ; Malaria ; Parasites ; Plasmodium ; Polymerase Chain Reaction ; Reagent Kits, Diagnostic ; Uganda

Plasmodium vivax is more challenging to control and eliminate than P. falciparum due to its more asymptomatic infections with low parasite densities making diagnosis more difficult, in addition to its unique biological characteristics. The potential re-introduction of incidence cases, either through borders or via human migrations, is another major hurdle to sustained control and elimination. The Republic of Korea has experienced re-emergence of vivax malaria in 1993 but is one of the 32 malaria-eliminating countries to-date. Despite achieving successful nationwide control and elimination of vivax malaria, the evolutionary characteristics of vivax malaria isolates in the Republic of Korea have not been fully understood. In this review, we present an overview of the genetic variability of such isolates to increase understanding of the epidemiology, diversity, and dynamics of vivax populations in the Republic of Korea.
Asymptomatic Infections ; Diagnosis ; Epidemiology ; Genetic Variation ; Human Migration ; Incidence ; Korea ; Malaria ; Malaria, Vivax ; Parasites ; Plasmodium vivax ; Plasmodium ; Population Characteristics ; Republic of Korea

BACKGROUND: Chemoprophylaxis has been used to prevent malaria among soldiers and secondary transmission, as it effectively facilitates a decline in disease occurrence and secondary prevention. However, poor compliance and decreased risk of exposure to malaria necessitate that control strategies be reestablished. METHODS: To predict the incidence of malaria according to a control strategy, we proposed a mathematical model for its transmission using epidemiological data from 2010 to 2012. The benefit component included in the analyses was the averted cost with each control strategy, and the cost components were the cost of implementing chemoprophylaxis and early diagnosis. RESULTS: The chemoprophylaxis regimen with hydroxychloroquine sulfate and primaquine was Intervention 1, the regimen with primaquine only was Intervention 2, and diagnosis with a rapid diagnostic test (RDT) kit within 5 days of fever was Intervention 3. The simulation indicated that the combined control program with chemoprophylaxis and early diagnosis would be the most effective strategy, whereas sole early diagnosis would be the least effective strategy. However, the cost-benefit ratio of chemoprophylaxis was less than Intervention 1, irrespective of the varying range of chemoprophylaxis compliance, and that of early diagnosis was more than Intervention 1, regardless of the varying early diagnosis rate and demand for the RDT kit. Although chemoprophylaxis would be more effective at reducing the incidence of malaria than early diagnosis, it is less economical due to the higher cost. CONCLUSION: Our results support the introduction of early diagnosis with a RDT kit to control malaria in the Republic of Korea Army.
Chemoprevention* ; Compliance ; Cost-Benefit Analysis* ; Diagnosis ; Diagnostic Tests, Routine ; Early Diagnosis* ; Fever ; Humans ; Hydroxychloroquine ; Incidence ; Malaria* ; Military Personnel* ; Models, Theoretical ; Primaquine ; Republic of Korea ; Secondary Prevention