Contribution of Plasmodium knowlesi to Multispecies Human Malaria Infections in North Sumatera, Indonesia.

Background: As Indonesia works toward the goal of malaria elimination, information is lacking on malaria epidemiology from some western provinces. As a basis for studies of antimalarial efficacy, we set out to survey parasite carriage in 3 communities in North Sumatera Province. Methods: A combination of active and passive detection of infection was carried out among communities in Batubara, Langkat, and South Nias regencies. Finger-prick blood samples from consenting individuals of all ages provided blood films for microscopic examination and blood spots on filter paper. Plasmodium species were identified using nested polymerase chain reaction (PCR) of ribosomal RNA genes and a novel assay that amplifies a conserved sequence specific for the sicavar gene family of Plasmodium knowlesi. Results: Of 3731 participants, 614 (16.5%) were positive for malaria parasites by microscopy. PCR detected parasite DNA in samples from 1169 individuals (31.3%). In total, 377 participants (11.8%) harbored P. knowlesi. Also present were Plasmodium vivax (14.3%), Plasmodium falciparum (10.5%) and Plasmodium malariae (3.4%). Conclusions: Amplification of sicavar is a specific and sensitive test for the presence of P. knowlesi DNA in humans. Subpatent and asymptomatic multispecies parasitemia is relatively common in North Sumatera, so PCR-based surveillance is required to support control and elimination activities

Plasmodium falciparum Isolates Carrying pfk13 Polymorphisms Harbor the SVMNT Allele of pfcrt in Northwestern Indonesia.

Artemisinin-based combination therapy (ACT) is the first-line antimalarial regimen in Indonesia. Susceptibility of Plasmodium falciparum to artemisinin is falling in the Greater Mekong subregion, but it is not known whether the efficacy of current combinations is also threatened in nearby Sumatera. We evaluated the genetic loci pfcrt, pfmdr1, and pfk13, considered to be under selection by artemisinin combination therapy, among 404 P. falciparum infections identified by PCR detection in a cross-sectional survey of 3,731 residents of three regencies. The pfcrt haplotype SVMNT (codons 72 to 76) was the most prevalent and displayed significant linkage disequilibrium with the pfmdr1 haplotype YY (codons 86 and 184) (odds ratio [OR] 26.7; 95% confidence interval [CI], 5.96 to 239.4; P < 0.001). This contrasts with Mekong countries, where the CVIET haplotype of pfcrt predominates. Among 231 evaluable isolates, only 9 (3.9%) showed any evidence of nonsynonymous gene variants in the propeller domain of pfk13 The Thr474Ala variant was seen in six individuals, and Cys580Tyr was identified with low confidence in only a single isolate from an asymptomatic individual. Among a subset of 117 symptomatic P. falciparum-infected individuals randomized to receive either dihydroartemisinin-piperaquine or artemether-lumefantrine, the treatment outcome was not associated with pretreatment genotype. However, submicroscopic persistent parasites at day 28 or day 42 of follow-up were significantly more likely to harbor the pfmdr1 haplotype NF (codons 86 and 184) than were pretreatment isolates (P < 0.001 for both treatment groups). Current ACT regimens appear to be effective in Sumatera, but evidence of persistent submicroscopic infection in some patients suggests further detailed studies of drug susceptibility should be undertaken

Contribution of Plasmodium knowlesi to multi-species human malaria infections in North Sumatera, Indonesia

Background As Indonesia works towards the goal of malaria elimination, information is lacking on malaria epidemiology from some western provinces. As a basis for studies of antimalarial efficacy, we set out to survey parasite carriage in three communities in North Sumatera Province. Methods A combination of active and passive detection of infection was carried out among communities in Batubara, Langkat and South Nias regencies. Finger-prick blood samples from consenting individuals of all ages provided blood films for microscopic examination and blood spots on filter paper. Plasmodium species were identified by nested PCR of rRNA genes, and a novel assay which amplifies a conserved sequence specific for the sicavar gene family of P. knowlesi. Results 614 of 3,731 participants (16.5%) were positive for malaria parasites by microscopy. PCR detected parasite DNA in samples from 1,169 individuals (31.3%). In total, 377 participants (11.8%) harboured P. knowlesi. Also present were P. vivax (14.3%), P. falciparum (10.5%) and P. malariae (3.4%). Conclusions Amplification of sicavar is a specific and sensitive test for the presence of P. knowlesi DNA in humans. Subpatent and asymptomatic multi-species parasitaemia is relatively common in North Sumatera, and so PCR-based surveillance is required to support control and elimination activities

Malaria epidemiology in central Myanmar: identification of a multi-species asymptomatic reservoir of infection.

BACKGROUND: The spread of artemisinin-resistant Plasmodium falciparum is a global health concern. Myanmar stands at the frontier of artemisinin-resistant P. falciparum. Myanmar also has the highest reported malaria burden in Southeast Asia; it is integral in the World Health Organization's plan to eliminate malaria in Southeast Asia, yet few epidemiological data exist for the general population in Myanmar. METHODS: This cross-sectional, probability household survey was conducted in Phyu township, Bago Region (central Myanmar), during the wet season of 2013. Interviewers collected clinical and behavioural data, recorded tympanic temperature and obtained dried blood spots for malaria PCR and serology. Plasmodium falciparum positive samples were tested for genetic mutations in the K13 region that may confer artemisinin resistance. Estimated type-specific malaria PCR prevalence and seroprevalence were calculated, with regression analysis to identify risk factors for seropositivity to P. falciparum. Data were weighted to account for unequal selection probabilities. RESULTS: 1638 participants were sampled (500 households). Weighted PCR prevalence was low (n = 41, 2.5%) and most cases were afebrile (93%). Plasmodium falciparum was the most common species (n = 19. 1.1%) and five (26%) P. falciparum samples harboured K13 mutations. Plasmodium knowlesi was detected in 1.0% (n = 16) and Plasmodium vivax was detected in 0.4% (n = 7). Seroprevalence was 9.4% for P. falciparum and 3.1% for P. vivax. Seroconversion to P. falciparum was 0.003/year in the whole population, but 16-fold higher in men over 23 years old (LR test p = 0.016). DISCUSSION: This is the first population-based seroprevalence study from central Myanmar. Low overall prevalence was discovered. However, these data suggest endemic transmission continues, probably associated with behavioural risk factors amongst working-age men. Genetic mutations associated with P. falciparum artemisinin resistance, the presence of P. knowlesi and discrete demographic risk groups present opportunities and challenges for malaria control. Responses targeted to working-age men, capable of detecting sub-clinical infections, and considering all species will facilitate malaria elimination in this setting

Comparison of RT-PCR cycle threshold values between individual and pooled SARS-CoV-2 infected nasopharyngeal swab specimens

The molecular reverse transcription-polymerase chain reaction (RT-PCR) testing of respiratory tract swabs has become mandatory to confirm the diagnosis of coronavirus disease 2019 (COVID-19). However, RT-PCR tests are expensive, require standardized equipment, and relatively long testing times, and the sample pooling method has been introduced to solve this issue. The aim of this study was to compare the cycle threshold (Ct) values of the individual sample and pooled sample methods to assess how accurate the pooling method was. Repeat RT-PCR examinations were initially performed to confirm the Ct values for each sample before running the pooled test procedure. Sample extraction and amplification were performed in both assays to detect ORF1ab, N, and E genes with a cut-off point value of Ct &lt;38. Overall, there was no difference in Ct values between individual sample and pooled sample groups at all concentrations (p=0.259) and for all pooled sizes. Only pooled size of five could detect the Ct value in the pooled samples for all concentration samples, including low-concentration sample (Ct values 36 to 38). This study highlighted that pooled RT-PCR testing strategy did not reduce the quality of individually measured RT-PCR Ct values. A pool size of five could provide a practical technique to expand the screening capacity of RT-PCR

A pediatric case and literature review of mucormycosis: Diagnostic and treatment challenges in a resource poor setting

Mucormycosis is an emerging disease that primarily affects immunocompromised patients; however, it has also been reported in immunocompetent individuals. Studies in the pediatric population are limited and reported mostly in case studies or series. The aim of this case report is to present a pediatric mucormycosis originated from Sumatra Island, Indonesia. A 13-year-old boy was referred to a tertiary hospital with facial necrosis involving the nasal, oral, and left maxillary areas, as well as left periorbital edema. No known underlying conditions were documented. The diagnosis was confirmed by histopathological findings of broad, pauci-septate, ribbon-like hyphae branching at 90°. The patient was managed by a multidisciplinary team consisting of the ear, nose, and throat, infectious diseases, dermatology, surgery, microbiology, and pathology departments. Management of the patient included debridement of the necrotic lesion and antibiotics and anti-fungal (fluconazole). Due to unavailability, the patient was not treated with amphotericin B. The patient died after 30 days of admission. This case highlights the importance of maintaining a high suspicion of invasive mucormycosis, even in immunocompetent children, when symptoms and signs are present, especially in resource-limited settings

Norwegian scabies in human immunodeficiency virus and tuberculosis-infected child: A case report

Norwegian scabies is a rare scabies with the manifestation of thick crusts of the extremities of the skin that contain eggs and mites. Several conditions in which scabies infection is easily transmitted include immunocompromised, home nursing, and severe neurological disorder. The aim of this case report was to present a thorough analysis of a comprehensive resource for the management of Norwegian scabies patients, with a specific focus on individuals who also have HIV or other immunocompromising diseases.  A 1-year-and-7-month-old boy was presented to the hospital with a chief complaint of a thick crust that he had experienced for four months. It began as a red papule in the lower extremity, then crusted and spread to the whole body. The patient kept scratching due to itching, had a recurrent fever and diarrhea for three months, and cough for one month. The patient was diagnosed with human immunodeficiency virus (HIV) and pulmonary tuberculosis at three months, suspected to get the infection from the parents. Sarcoptes scabiei was found from microscopy examination of skin scraping. The patient received holistic treatment, including antiretroviral drugs, antituberculosis medication, scabies treatment, and malnutrition treatment. Appropriate scabies treatment aimed at peeling crusted skin, relieving itching, and increasing the patient ability to use the extremities. Comorbidity conditions caused by HIV and pulmonary tuberculosis should also be treated to optimize the outcome. The patient was discharged in good condition with sanitation education and regular follow-up at the outpatient clinic. This case highlights that Sarcoptes scabiei infestation may be a clue to an immunocompromised condition. Holistic therapy aiming to cure underlying infection, infestation and underlying nutrition and psychosocial problems must be addressed to fully cure this high-burden case