Rapid Diagnostic Kits Research Articles

Diagnostic performance of Typhidot RDT in diagnosis of typhoid fever and antibiotic resistance characterisation in a cross-sectional study in Southern Ghana

BackgroundTyphoid fever remains a significant public health problem contributing to significant misapplication of antibiotics in Ghana. However, there is little data on the accuracy of the commonly used serology based rapid diagnostic Typhidot test kit (Typhidot RDT) for confirming typhoid fever.MethodsWe conducted a study to assess the diagnostic accuracy of Typhidot RDT in seven clinical facilities across five regions in Southern Ghana. A total of 258 participants, clinically diagnosed with typhoid fever, were enrolled in this study. Blood and stool samples were obtained for culture, Typhidot and PCR assays. Disc diffusion antibiotic sensitivity was performed to determine the resistance pattern of Salmonella enterica isolates from positive blood and stool cultures.ResultsRecovery of S. enterica isolates was higher from stool samples (14.7%) in comparison to blood samples (1.6%). The sensitivity and specificity of Typhidot compared to blood and stool cultures was 35% (19.94%—52.65%) and 45% (38.67%—51.45%), respectively. Compared to PCR, the Typhidot had a sensitivity and a specificity of 61% and 53%, respectively. Resistance phenotyping of isolates showed broad sensitivity to the front-line antibiotics used. Resistance to ampicillin (10%), cotrimoxazole (7%), azithromycin and ciprofloxacin (< 5%) was found in some isolates.ConclusionsThese findings suggest sub-optimal performance of the Typhidot RDT for diagnosis of typhoid in Ghana with a higher chance for misdiagnosis and misapplication of antibiotics. The high proportion of isolates recovered from stool culture is consistent with the pathophysiology of bacterial shedding during the acute phase of infection, which provides a window of opportunity to control typhoid transmission.

A gold nanoparticle conjugated single-legged DNA walker driven by catalytic hairpin assembly biosensor to detect a prokaryotic pathogen

Catalytic hairpin assembly (CHA)-DNA walker allows nanostructures to spontaneously hybridize to the nucleic acids. The localized surface plasmon resonance provides the ability of color-shift for Au nanoparticles (AuNPs) to design a colorimetric biosensor by implementing CHA-DNA walker reaction on AuNPs. A target gene in Klebsiella pneumoniae as the reaction cascade trigger, was selected. H1 and H2 oligonucleotides as the components of the system were designed and verified by NUPACK. The AuNPs were conjugated to H1. The conjugation of the probes to the AuNPs was evaluated using FT-IR. The signal amplification process was conducted at 25℃. TEM imaging, zeta potential, spectroscopy, and gel-electrophoresis were used to examine the conduction of the reaction cascade and specificity. The sensitivity of the method was analyzed using serial dilution of the target. The formation of over-52 bp intermediate secondary structures (which only exist when the reaction happens) was confirmed by gel-electrophoresis. The color distinction between positive (0.08 to 0.058) and negative samples (0.098 to 0.05) was evidenced instantly and in a period of 90 min of the reaction as a drop change of 520 nm intensity absorbance. TEM imaging confirmed the further distance of AuNPs in the positive sample in comparison to that of the negative sample which reveals effective detection of the pathogen. The LOD of the technique was measured as 2.5 nM of the target sequence. The diagnostic approach is a label-free, enzyme-independent approach and can be executed in a single step. It has been designed by employing the CHA-DNA walker system along with the colorimetric properties of AuNPs for the first time, thereby paving the way for more rapid and accurate diagnostic kits.

Clinico-haematological and Serum Biochemical Changes Associated with Foot and Mouth Disease in some Breeds of Cattle in Oyo State, Nigeria

Foot and mouth disease is considered one of the major hindrances to the growth of animal husbandry in Nigeria, with a projected annual loss of about 7 billion naira. We sought to establish the hematological and biochemical features in Nigerian indigenous cattle naturally infected with FMDV by comparing the hematological and biochemical features with breed, sex, and age. Forty cattle showing clinical manifestations and confirmed positive for FMD with the FMD rapid diagnostic kit were sampled for this study. Standard hematological and serum biochemical techniques were adopted for the analysis. Demography findings revealed more clinical FMD cases in the White Fulani breed (50%) compared to the least in Red Bororo (10%), females (60%) compared to males (40%), and adults (60%) compared to young (40%) cattle, respectively. There were generalized neutrophilia, lymphopenia, hypoproteinemia, increased ALT, and decreased AST enzymes when compared with reference ranges. All parameters analyzed regarding sex revealed no significance in their mean ± standard deviation, except neutrophils and absolute neutrophils, with p-values of 0.022 and 0.003, respectively. The results of all parameters regarding ages showed no statistical significance when comparisons of their mean ± SD were analyzed. We therefore conclude that there were more incidences of FMD in white Fulani, female, and adult cattle compared to other breeds, male and young animals, respectively, in Nigeria. The hematological and biochemical features appeared better in the Red Bororo breed, female and adult FMD-infected cattle compared to other breeds, male and young FMD-infected cattle respectively.

Molecular Detection of Malaria Co-Infections with Some Arboviruses in Pregnant Women Attending Ante-Natal in Hospitals within Bauchi State, Nigeria

Malaria and arboviruses are public health menaces, causing major morbidity in developing countries and are more severe in pregnancy leading to adverse effects which can lead to fetal and maternal death, hence, this study determined the prevalence of dengue, zika and malaria infections among pregnant women attending antenatal clinics in some hospitals within Bauchi Local Government Area, Bauchi State, Nigeria. One hundred and seventy-seven blood samples of pregnant women were collected and screened for malaria using the Rapid Diagnostic test kits, while the diagnosis for dengue and zika infections was done using real time Polymerase Chain Reaction (RT-qPCR). From the blood samples tested, 50 (28.25%) were positive for malaria, 1 (2.00%) sample was positive for dengue and dengue-malaria co-infection, however, no sample was positive for zika virus (0%). Malaria was recorded across all the age groups with a high statistical significance, dengue was prevalent between age 15-25years (2.35%) and 26-35years (1.35%) while dengue-malaria co-infection was only seen in age group 15-25years (1.18%). Pregnant women with fever and the trimesters were significantly associated with the prevalence of malaria (P&lt;0.05 respectively); Educational qualification and occupation were significantly associated with dengue infections (P&lt;0.05 for both) as well as dengue-malaria co-infection (P=0.05 for both), whereas history of miscarriages was only statistically associated with prevalence of dengue infections (P=0.02204). Despite the low prevalence of dengue virus among pregnant women in this study, the result of this study gives an overview of dengue, zika and malaria in Bauchi, thereby providing the first baseline data.

Prevalence and factors associated with malaria among children aged 6 months to 10 years in the Greater Accra Region of Ghana: a community-based cross-sectional survey

BackgroundMalaria remains a major public health problem, especially among children in sub-Saharan Africa. Knowledge of malaria parasite prevalence informs targeted interventions and helps to monitor the effectiveness of those interventions. This study aimed to determine prevalence and factors associated with malaria in children aged 6 months to 10 years in the Greater Accra Region of Ghana.MethodsA community-based cross-sectional study was conducted among 8,741 children aged 6–59 months and 8,292 children aged 5–10 years in all 29 districts of the Greater Accra Region of Ghana in October 2020. Systematic random sampling was used to select communities, households and study participants. A structured questionnaire was used to collect data from caregivers. Rapid diagnostic test kits were used to determine the presence of malaria parasites in blood samples collected by fingerprick. Factors associated with malaria RDT-positivity were determined using multivariate logistic regression analysis.ResultsOf 8727 children aged 6–59 months and 8279 aged 5–10 years from whom blood samples were obtained, positive results were obtained for 289 (3.3%; 95% CI 3.0–3.7) and 406 (4.9%; 95% CI 4.5–5.4) respectively. Malaria parasite prevalence in the districts ranged from 0.9 to 10.7% and 1.4–15.0% in children aged 6–59 months and 5–10 years respectively. Factors associated with increased odds of malaria included higher age (AOR = 1.43; 95% CI 1.14–1.71), and living in households without nets on the windows (AOR 1.64; 95% CI 1.10–2.45). On the other hand, living in households located in urban communities was associated with a lower risk of malaria (AOR 0.56; 95% CI 0.40–0.78).ConclusionThe average prevalence of malaria in the Greater Accra Region is low compared with other regions. However, there are potential hotspots that need to be targeted with appropriate interventions to accelerate the drive towards malaria elimination.

Triple burden of hepatitis B, hepatitis Delta viruses, and Plasmodium falciparum to pregnant women

ObjectivesChronic hepatitis B virus (HBV) infection remains a major health problem worldwide. This infection is more severe when combined with hepatitis Delta virus (HDV). Moreover, Plasmodium falciparum (Pf) malaria infection during pregnancy can have severe consequences for the mother and the newborn. Importantly, the manifestation of these three infections has never been described to date. MethodsThus, we conducted a prospective study, between May 27, 2022, and April 15, 2023, and we investigated these three infections in 260 pregnant women aged 24 to 46 years, in Gabon and evaluated the impact on newborns. The sera were used to screen hepatitis B surface antigen (HBsAg) and Pf by determining HBsAg® ALERE rapid diagnostic test and malaria rapid diagnostic test kits. The positive sample was confirmed using MINI VIDAS® for HBV and Lambaréné method for “Pf”. The real-time-polymerase chain reaction assay was used to amplify HBV DNA and HDV RNA on Roche instrument. ResultsOur results showed that the prevalences of HBV and (Pf) infection were 4.23% (n = 11) and 34.62% (n = 90), respectively. Moreover, we found that 3.46 % (n = 9) of pregnant women infected with HBV were coinfected with HDV. The prevalence of triple infection was 1.15% (n = 3). In addition, the leukocytes and lymphocytes absolute count were significantly lower for the triple-infected pregnant women. ConclusionsWe describe for the first time the triple coinfection by HBV, HDV, and Pf, which could induce a great inflammatory reaction and high liver disorder in newborns.

A novel peptide pair-based rapid fluorescent diagnostic system for malaria Plasmodium falciparum detection

Advanced diagnostic materials, such as aptamers, are required due to the scarcity of efficient diagnostic antibodies and the low sensitivity of rapid diagnostic kits at detecting the malaria parasite, Plasmodium falciparum. MethodsTwo peptides M2.9 [(KPTAEQTESPELQSAPEN) and M2.17 (KILFNVYSPLGCTCECWV)] were designed using simple epitope prediction tools and modified against the merozoite surface antigen 2 of P. falciparum (Pf.MSP2) by 3-dimensional modeling based on binding affinity. Based on five prediction tools for hydropathy, M2.17 was selected as an appropriate capture peptide. A peptide-based fluorescence-linked immunosorbent assay (FLISA) and a peptide pair-based fluorescent immunochromatographic test strip (FICT) were developed to detect P. falciparum 3D7 (drug-sensitive) and P. falciparum K1 (multi drugs-resistant) strains. ResultsBioinformatic analysis of two peptides demonstrated the potential binding affinity with the merozoite surface protein 2 of P. falciparum (Pf.MSP2) with a positive hydropathy value. The limit of detection (LOD) of FLISA was 10 parasites/μL and of a peptide pair-linked rapid FICT system was 5 and 200 parasites/μL for P. falciparum 3D7 and K1, respectively. Compared to commercial rapid detection systems (RDTs), a peptide pair-linked FICT system exhibited a 20-fold greater efficiency in detecting P. falciparum 3D7 and specifically discriminated another protozoan spp. ConclusionA peptide pair-linked rapid diagnostic strip could be an alternative to conventional RDTs for monitoring wild-type and drug-resistant malaria parasites.

1H-NMR Analysis of Amino Acid Metabolism in Cerebrospinal Fluid of Dogs with Neurological Distemper

Abstract Canine Distemper Virus (CDV) infection causes a multifocal demyelinating progressive disease within the central nervous system (CNS) that results in wide range of neurological symptoms. Pathological changes in the brain or CNS could be observed by analyzing cerebrospinal fluid (CSF). Therefore, this study aimed to investigate the concentrations of amino acids in the CSF of dogs with neurological form of CDV infection, and to identify amino acids as markers that can be used in the diagnosis, pathogenesis, and treatment of the disease. Heathy dogs (n=6), confirmed by clinical and laboratory examinations (Healthy group), and CDV-infected dogs (n=10) with neurological symptoms, confirmed by clinical, laboratory, and rapid diagnostic test kits (Distemper group), were used. CSF samples were obtained with an appropriate method and were subjected to 1H-NMR analysis. Identification was made on 10, whereas quantification on 8 amino acids. L-tyrosine, L-phenylalanine, L-threonine, and L-alanine concentrations were significantly lower, while L-histidine and L-tryptophan were significantly higher than the Healthy group (p&lt;0.05). It was concluded that L-tyrosine could be used for assessing mental status changes, L-phenylalanine for evaluating neuroprotective responses, L-threonine and L-histidine for gauging the extent of neurodegeneration and ventricular degeneration, L-alanine for exploring cellular stress and energy metabolism, and L-tryptophan for understanding the process of sympathetic nervous system activation.

Long-lasting insecticidal nets use and the prevalence of Plasmodium falciparum infection among pregnant women attending antenatal care at the Bonassama District Hospital, Littoral Region of Cameroon: a cross-sectional study

BackgroundMalaria during pregnancy continues to be a significant cause of morbidity and mortality for both infants and mothers, particularly in sub-Saharan African (SSA) countries, despite increased efforts to control it. The utilization of long-lasting insecticide-treated nets (LLINs) during pregnancy is a well-established strategy to reduce the prevalence of malaria. Nonetheless, inadequate adherence remains a persistent challenge in certain regions with high malaria endemicity. This research aimed to assess the effectiveness of long-lasting insecticidal nets in preventing asymptomatic malaria infections among pregnant women attending antenatal care at the Bonassama District Hospital in the Littoral Region of Cameroon.MethodsA hospital-based cross-sectional study was conducted from March to June 2022. Data on sociodemographic characteristics and LLIN usage were collected through a structured questionnaire, while asymptomatic malaria infections were identified using a PfHRP2/pLDH malaria qualitative rapid diagnostic kit. The relationship between categorical variables was analyzed using the chi-square test and logistic regression at a significance level of 5%.ResultsOut of the 411 pregnant women included in the study, 35.4% were diagnosed with malaria. The LLIN utilization rate was 65.1%. The risk of malaria infection was 2.7 times higher (AOR = 2.75, 95% CI = 1.83–4.14, p < 0.001) among women who did not consistently use LLINs compared to those who did. Pregnant women in their first trimester (AOR = 3.40, 95% CI = 1.24–4.64, p = 0.010) and second trimester (AOR = 1.90, 95%CI = 0.99–3.62, p = 0.055) were more likely to sleep under net when compared to those in the third trimester. Younger women 20–29 years (71.4%), those in the first trimester (69.6%) and those who had the nets before pregnancy (68.9%) were amongst those who frequently used use the nets. Among the reasons reported for not frequently using LLINs were heat (55.2%), suffocation (13.6%) and the smell of nets (8.4%).ConclusionThe use of LLIN was moderately high among the participants in this study, though still below national target. Age group, religion and gestation period were the major factors determining the use of LLINs. Considering the proven effectiveness of LLINs in reducing malaria morbidity and mortality, it is imperative for the National Malaria Control Programme (NMCP) to remain focused in promoting both LLIN ownership and utilization to achieve the national target of 100% and 80%, respectively.

Comparative Performance of Four Rapid Diagnostic Tests Kits, Microscopy and PCR in Asymptomat-ic Malaria Detection among Children from Ilishan-Remo Community, Southwest Nigeria

Comparative Performance of Four Rapid Diagnostic Tests Kits, Microscopy and PCR in Asymptomat-ic Malaria Detection among Children from Ilishan-Remo Community, Southwest Nigeria

Evaluation of immunophenotypic alterations of peripheral blood lymphocytes and their sub-sets in uncomplicated P. Falciparum infection

BackgroundMalaria is a life-threatening parasitic disease typically transmitted through the bite of an infected Anopheles mosquito. There is ample evidence showing the potential of malaria infection to affect the counts of lymphocyte subpopulations in the peripheral blood, but the extent of alteration might not be consistent in all geographical locations, due to several local factors. Although Ghana is among the malaria-endemic countries, there is currently no available data on the level of alterations that occur in the counts of lymphocyte subpopulations during P. falciparum malaria infection among adults.AimThe study was to determine the immunophenotypic alterations in the level of peripheral blood lymphocytes and their subsets in adults with uncomplicated P. falciparum malaria infection and apparently healthy participants.MethodsThe study was a cross-sectional comparative study conducted in two municipalities of the Volta region of Ghana. Blood samples were collected from study participants and taken through serology (P. falciparum/Pan Rapid Diagnostic Kits), microscopy (Thick and thin blood films) and Haematological (Flow cytometric and Full blood count) analysis.ResultsA total of 414 participants, comprising 214 patients with malaria and 200 apparently healthy individuals (controls) were recruited into this study. Parasite density of the malaria patients ranged from 75/µL to 84,364/µL, with a mean of 3,520/µL. It was also observed that the total lymphocytes slightly decreased in the P. falciparum-infected individuals (Mean ± SD: 2.08 ± 4.93 × 109/L) compared to the control group (Mean ± SD: 2.47 ± 0.80 × 109/L). Again, there was a significant moderate positive correlation between parasite density and haematocrit levels (r = 0.321, p < 0.001). Apart from CD45 + T-cells, more people in the control group had normal values for the lymphocyte subsets measured compared to the malaria patients.ConclusionsFrom the results obtained, there was high parasite density among the malaria patients suggestive of high intensity of infection in the case group. The malaria patients again showed considerable haematological alterations in lymphocyte sub-sets and the parasite density appeared to be strongly associated with CD4 + T-cell reduction. Also, the parasite density significantly associated with decreasing haematocrit levels. This indicates that lymphocyte subset enumeration can be used to effectively support malaria diagnosis.

Chicken IgY based electrochemical immunosensor for the detection of bacterial pathogen E. coli in water

On a global scale, approximately 1 in 8 (13.6 %) of worldwide mortalities have been associated with bacterial infections. Therefore, the necessity for rapid and cost-effective diagnostic kits is paramount to accurately diagnose bacterial infections. Besides, the utilization of IgY antibodies emerges as a natural and economical option for effective sensing of pathogens. Notably, electrochemical IgY-based immunosensors amalgamate the inherent specificity of immunoreactions with highly sensitive electrochemical sensors, thereby facilitating the advancement of next generation Point-of-Care (POC) devices. In this work, a label-free IgY-based immunosensor for the detection of E. coli, employing Boron and Nitrogen-doped Graphene Quantum Dots (B, N-doped GQDs) nanomaterial as the electrode interface was successfully devised. This developed immunosensor has demonstrated commendable sensitivity of 0.0395 µA. (CFU/mL)−1 & 0.0491 µA. (CFU/mL)−1 from Cyclic Voltammetry (CV) & Amperometry (Amp) techniques across various E. coli concentrations (0.5 x 101 – 107 CFU/mL) and exhibited exceptional selectivity of < 5.88 %, thereby ensuring precise E. coli detection while mitigating interference from other agents. Moreover, real sample analysis with the developed sensor displayed exemplary recoveries, affirming its efficacy in detecting E. coli. The immunosensor’s promising results in terms of its figures-of-merit underscore the potential diagnostic utility of IgY in E. coli screening bacterial sensing applications.

Haematological Profile in Patients With Acute Falciparum Malaria: A Hospital-Based Study.

Introduction Malaria is the most common parasitic disease affecting humans. Haematological alterations in malaria are expected, and these changes play a significant role in fatal complications. The present study aims to assess the clinical and haematological profile in patients with acute falciparum malaria and the significance of various haematological and coagulation alterations with the clinical severity of malaria. Methods The prospective cross-sectional study included 68 acute falciparum malaria cases. Thick and thin blood film microscopy and a rapid diagnostic kit were used to diagnose malaria. The cases were subjected to various haematological and biochemical investigations. Bone marrow aspiration samples were also collected. Using appropriate statistical methods, the findings were compared between severe and uncomplicated malaria cases. A p-value below 0.05 was considered significant. Results The participants' ages ranged from 14 to 78. Most participants (n = 51, 75%) were male and belonged to the lower income group (33, 48.5%). Significant variations in mean parasite count between severe and uncomplicated malaria cases (p-value < 0.01) were observed. The severe and uncomplicated groups showed significant differences in haemoglobin (gm/dL), haematocrit, red blood cell count, reticulocyte, serum iron, and ESR levels (p-value < 0.05). The severe malaria group had considerably reduced mean platelet counts (p-value < 0.01). Only five instances (7.3%) had an appropriate erythropoietic response after day 28. Erythroid hyperplasia with dyserythropoietic alterations was most common in patients with severe anaemia and low-grade parasitaemia. Conclusion Acute falciparum malaria is often associated with haematological alterations. Anaemia and thrombocytopenia were the most expected alterations associated with disease prognosis and mortality.

Prevalence of Malaria among Patients attending Federal Medical Centre, Owerri, Imo State, Nigeria

The malaria parasite is a parasitic protozoan (a group of single-celled microorganisms) that inflicts humans with malaria. It is responsible for a significant proportion of the health burden of developing countries. Thus, this study aimed to evaluate the prevalence of malaria among patients attending the Federal Medical Centre Owerri, Imo State, Nigeria. A total of 150 patients consented to participate. Malaria diagnosis was performed using rapid diagnostic test kits and microscopic examination of Giemsa-stained blood film. Questionnaires were administered to gather socio-demographic data. The analysis revealed a 53% prevalence of malaria. Statistical analysis indicated associations between malaria occurrence and gender, educational level, and economic status. This study highlights the high prevalence of malaria among patients at FMC Owerri.

Evaluation of rapid diagnostic test kits for detection of Treponema pallidum antibody.

Rapid syphilis testing plays a crucial role in global health strategies, addressing the urgent need for prompt and accurate diagnostics, especially in settings with limited resources. Despite their practical utility, these tests often lack thorough validation, leading to concerns about their efficacy and reliability. This study aims to evaluate two prototypes of the Onsite Syphilis Ab Combo Rapid Test (Fd and Ff) and compare their performance with the established chemiluminescent microparticle immunoassay (CMIA) method. Employing a reverse algorithm approach, the study analyzed 450 serum samples, including those from syphilis patients, healthy individuals, and cases with potential cross-reactions. Results of the rapid test kit were then correlated with CMIA findings, RPR, and TPPA titers. The results showed that prototype Fd exhibited a sensitivity of 100.0%, specificity of 98.8%, positive predictive value (PPV) of 8.4%, negative predictive value (NPV) of 100.00% and accuracy of 98.8%. Similarly, prototype Ff exhibited sensitivity of 100.0%, but with a slightly higher specificity of 99.6%, PPV of 21.5%, NPV of 100.0% and accuracy of 99.6%. Moreover, both prototypes Fd and Ff of the Onsite Syphilis Ab Combo Rapid Test demonstrated significant efficacy diagnostic tool, offering clear and straightforward interpretation for clinicians in varied CMIA, RPR and TPPA titer scenarios. The Onsite Syphilis Ab Combo Rapid Test prototypes, Fd and Ff, demonstrated high sensitivity and specificity, comparable to CMIA methods. The effectiveness highlights their suitability for syphilis screening, particularly in non-laboratory settings or situations requiring immediate results. The validation of these prototypes supports their integration into current syphilis diagnostic algorithms, potentially contributing to improved public health outcomes.

Sub-microscopic Plasmodium falciparum infections and multiple drug resistant single nucleotide polymorphic alleles in pregnant women from southwestern Nigeria

ObjectivesThe study evaluated sub-microscopic malaria infections in pregnancy using two malaria Rapid Diagnostic Tests (mRDTs), microscopy and RT-PCR and characterized Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and Plasmodium falciparum dihydropteroate synthase (Pfdhps) drug resistant markers in positive samples.MethodsThis was a cross sectional survey of 121 pregnant women. Participants were finger pricked, blood drops were collected for rapid diagnosis with P. falciparum histidine-rich protein 11 rapid diagnostic test kit and the ultra-sensitive Alere Pf malaria RDT, Blood smears for microscopy and dried blood spots on Whatman filter paper for molecular analysis were made. Real time PCR targeting the var acidic terminal sequence (varATS) gene of P. falciparum was carried out on a CFX 96 real time system thermocycler (BioRad) in discriminating malaria infections. For each run, laboratory strain of P. falciparum 3D7 and nuclease free water were used as positive and negative controls respectively. Additionally, High resolution melt analyses was employed for genotyping of the different drug resistance markers.ResultsOut of one hundred and twenty-one pregnant women sampled, the SD Bioline™ Malaria Ag P.f HRP2-based malaria rapid diagnostic test (mRDT) detected eight (0.06%) cases, the ultra-sensitive Alere™ malaria Ag P.f rapid diagnostic test mRDT had similar outcome in the same samples as detected by the HRP2-based mRDT. Microscopy and RT-PCR confirmed four out of the eight infections detected by both rapid diagnostic tests as true positive and RT-PCR further detected three false negative samples by the two mRDTs providing a sub-microscopic malaria prevalence of 3.3%. Single nucleotide polymorphism in Pfdhps gene associated with sulphadoxine resistance revealed the presence of S613 mutant genotypes in three of the seven positive isolates and isolates with mixed wild/mutant genotype at codon A613S. Furthermore, four mixed genotypes at the A581G codon were also recorded while the other Pfdhps codons (A436G, A437G and K540E) showed the presence of wild type alleles. In the Pfdhfr gene, there were mutations in 28.6%, 28.6%, and 85.7% at the I51, R59 and N108 codons respectively. Mixed wild and mutant type genotypes were also observed in 28.6% each of the N51I, and C59R codons. For the Pfcrt, two haplotypes CVMNK and CVIET were observed. The SVMNT was altogether absent. Triple mutant CVIET 1(14.3%) and triple mutant + wild genotype CVIET + CVMNK 1(14.3%) were observed. The Pfmdr1 haplotypes were single mutants YYND 1(14.3%); NFND 1(14.3%) and double mutants YFND 4(57.1%); YYDD 1(14.3%).

Evidence-based prevalence of HIV infection and associated risk factors among female sex workers in Port Harcourt, Niger Delta, Nigeria

Human Immunodeficiency Virus (HIV) epidemic has remained a key public health issue for the sub-Saharan countries including Nigeria. Thus, sex workers in the region are top on the list of key populations with highest vulnerability. The prevalence of HIV among female sex workers is twice the prevalence found in the general population in Sub-Saharan countries. This study evaluated the prevalence of HIV among female sex workers in Port Harcourt, Rivers State, Nigeria. A respondent-oriented observational sampling technique which involved the use of questionnaire in addition to laboratory-based screening of HIV among female sex workers in Port Harcourt was used. The self-structured questionnaire comprehensively explored socio-demographic characteristics, and risk factors among the subjects. HIV rapid diagnostic test kit from Alere Determine was used to detect HIV infection. This cross sectional study findings recorded that, from a sample of 200 participants drawn, 171 were negative to HIV while 29 subjects were positive to HIV infection with an overall prevalence of 14.5% among female sex workers in Rivers State. Furthermore, the finding demonstrated null association (p&gt;0.05) between HIV and the risk factors measured. The study implies that the risk of HIV among the study population, female sex workers, is not linked to the assumed risk factors measured in this study since the finding failed to establish association at p&gt;0.05. HIV awareness campaigns should be intensified among female sex workers especially on the consistent and correct use of condoms, and possibly bringing HIV testing to the sex partners and clients as secondary prevention strategy to offset the trend in HIV prevalence among this key population. Also implementation of intervention such as HIV pre-exposure prophylaxis following crucial riskful accident; such as condom breakage is suggested among female sex workers.

Comparative evaluation of the diagnostic accuracies of four different malaria rapid diagnostic test kits available in Ghana.

Malaria rapid diagnostic test (mRDT) kit is one of the techniques for diagnosing malaria. Due to its inherent advantages over the microscopy technique, several brands of the kit have flooded malaria endemic countries, without prior in-country evaluation. Two of such mRDT kits are Oscar (India) and Standard Q (Korea Republic). In this study, the performance of Oscar and Standard Q mRDT kits were compared to First Response (India) and CareStart (USA) mRDTs, which have been evaluated and deployed for use approved by the Ministry of Health (MOH). In this comparative study, whole blood samples were collected from patients suspected of malaria. Plasmodium falciparum was detected in each sample using nested polymerase chain reaction (nPCR), microscopy and the four mRDTs. The sensitivities, specificities, accuracies, positive and negative predictive values and accuracies of the mRDTs were determined using nPCR as a reference technique. Kappa statistic was used to determine the level of agreement among the techniques. Two hundred (200) blood samples were analyzed in this study. The overall detection rates of P. falciparum by microscopy, First Response, CareStart, Oscar-PfHRP2, Standard Q mRDT kits and nPCR were 31.5%, 34.5%, 33.5%, 32%, 31% and 43% (x2 = 6.1, p = 0.046), respectively. The accuracies of CareStart and First Response were comparable (90.5% vs. 89.5%). Further, comparing their sensitivities, Oscar-PfHRP2 was 74.4% (95% confidence interval (CI): 63.9-83.2) while that of Standard Q was 72.1% (95% CI: 61.4-81.2), with comparable accuracies (Oscar-PfHRP2-89% and Standard Q -88%). Apart from First Response that was 98.3% specific, the others were 100% specific. Kappa test revealed perfect diagnostic agreement (κ = 0.90-0.98) among the four mRDTs. That notwithstanding, Oscar-PfHRP2 agreed better with CareStart (κ = 0.94) and First Response (κ = 0.92) compared to the agreement between Standard Q and, CareStart (κ = 0.92) and First Response (κ = 0.90). Taken together, the diagnostic performance of the four mRDT kits were statistically similar. That notwithstanding, new mRDT kits should be evaluated prior to deployment for use.

An oleanic acid decorated gold nanorod for highly efficient inhibition of hemagglutinin and visible rapid detection of the influenza virus

Accurate diagnosis and effective antiviral treatments are urgently needed for the prevention and control of flu caused by influenza viruses. In this study, a novel oleanic acid (OA) functionalized gold nanorod OA-AuNP was prepared through a convenient ligand-exchange reaction. As hemagglutinin (HA) on the viral surface binds strongly to the multiple OA molecules on the surface of the nanoparticle, the prepared OA-AuNP was found to exhibit potent antiviral activity against a wide range of influenza A virus strains. Furthermore, the change in color resulting from the specific binding between HA and OA and the resultant aggregation of the OA-AuNP can be visually observed or measured by UV–vis spectra with a detection limit of 2 and 0.18 hemagglutination units (HAU), respectively, which is comparable to the commercially available influenza colloid gold rapid diagnostic kits. These findings demonstrate the potential of the OA-AuNP for the development of novel multivalent antiviral conjugates and the diagnosis of influenza virus.

Prevalence of rotavirus, coronavirus, Cryptosporidium spp, Escherichia coli K99 and Giardia lamblia in neonatal calves with diarrhea in Burdur and its districts

TThe aim of this study is to determine the prevalence of pathogens such as Rotavirus, Coronavirus, Cryptosporidium spp, Escherichia coli K99, and Giardia lamblia in neonatal calves with diarrhea in Burdur and its districts. The study material consisted of 96 diarrheic calves aged between 1 and 28 days from different cattle farms in the Burdur region. Fecal samples were collected, and the causative agents were identified using rapid diagnostic kits (BoviD-5 Ag Test Kit- BIONOTE). In the study, among the 96 diarrheic calves, a single enteropathogen was detected in 61 (63.54%), and 25 (26.04%) of these calves were positive for Cryptosporidium, 12 (12.5%) for E. coli K99, 11 (11.45%) for Rotavirus, 7 (7.29%) for Coronavirus, and 6 (6.25%) for Giardia lamblia, respectively. Multiple enteropathogens were responsible for diarrhea in 18 calves, and 2 (2.08%) of them were Cryptosporidium spp.+Giardia lamblia, 8 (8.33%) Cryptosporidium spp.+Rotavirus, 3 (3.12%) Coronavirus+Rotavirus, with 1 (1.04%) Coronavirus+Cryptosporidium spp., 2 (2.08%) Rotavirus+E. coli, and 1 (1.04%) of them was E. coli+Cryptosporidium spp.+Rotavirus. Among the 96 diarrheic calves with mixed infections or a single enteropathogen, 38 (39.58%) had Cryptosporidium, 15 (15.62%) had E. coli K99, 26 (27.08%) had Rotavirus, 12 (12.50%) had Coronavirus, and 8 (8.33%) had Giardia lamblia. However, in 17 of the 96 diarrheic calves, neither mono- nor multiple enteropathogens were detected, suggesting that other factors might have caused diarrhea. Finally, this research provides valuable information for faster diagnosis, prevention, control, and treatment of enteropathogens causing diarrhea in neonatal calves in the Burdur region, contributing to reducing calf losses. It is believed that the research findings will shed light on future studies.