Rapid Test Kit Research Articles

Evaluation of FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit for Detection of SARS-CoV-2 in Respiratory Samples from Mildly Symptomatic or Asymptomatic Patients.

Molecular tests are the gold standard to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but are associated with a diagnostic delay, while antigen detection tests can generate results within 20 min even outside a laboratory. In order to evaluate the accuracy and reliability of the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit (Ag-RDT), two respiratory swabs were collected simultaneously from 501 patients, with mild or no coronavirus disease 2019 (COVID-19)-related symptoms, and analyzed with both the Reverse Transcriptase-quantitative Polymerase Chain Reaction (RT-qPCR) and the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test. Results were then compared to determine clinical performance in a screening setting. We measured a precision of 97.41% (95% CI 92.42–99.15%) and a recall of 98.26% (95% CI 93.88–99.25%), with a specificity of 99.22% (95% CI 97.74–99.74%), a negative predictive value of 99.48% (95% CI 97.98–99.87%), and an overall accuracy of 99.00% (95% CI 97.69–99.68%). Concordance was described by a Kappa coefficient of 0.971 (95% CI 0.947–0.996). Considering short lead times, low cost, and opportunities for decentralized testing, the Ag-RDT test can enhance the efforts to control SARS-CoV-2 spread in several settings.

Can Self-Administered Rapid Antigen Tests (RATs) Help Rural India? An Evaluation of the CoviSelf Kit as a Response to the 2019-2022 COVID-19 Pandemic.

This paper evaluates India’s first officially approved self-administered rapid antigen test kit against COVID-19, a device called CoviSelf. The context is rural India. Rapid antigen tests (RATs) are currently popular in situations where vaccination rates are low, where sections of the community remain unvaccinated, where the COVID-19 pandemic continues to grow and where easy or timely access to RTPCR (reverse transcription-polymerase chain reaction) testing is not an option. Given that rural residents make up 66% of the Indian population, our evaluation focuses on the question of whether this self-administered RAT could help protect villagers and contain the Indian pandemic. CoviSelf has two components: the test and IT (information technology) parts. Using discourse analysis, a qualitative methodology, we evaluate the practicality of the kit on the basis of data in its instructional leaflet, reports about India’s ‘digital divide’ and our published research on the constraints of daily life in Indian villages. This paper does not provide a scientific assessment of the effectiveness of CoviSelf in detecting infection. As social scientists, our contribution sits within the field of qualitative studies of medical and health problems. Self-administered RATs are cheap, quick and reasonably reliable. Hence, point-of-care testing at the doorsteps of villagers has much potential, but realising the benefits of innovative, diagnostic medical technologies requires a realistic understanding of the conditions in Indian villages and designing devices that work in rural situations. This paper forms part of a larger project regarding the COVID-19 pandemic in rural India. A follow-up study based on fieldwork is planned for 2022–2023.

Determination of an optimal ELISA cut-off for the diagnosis of Toxoplasma gondii infection in pigs using Bayesian latent class modelling of data from multiple diagnostic tests

Toxoplasma gondii infection in pigs is commonly diagnosed using serological tests that detect IgG antibodies targeted against the parasite. Such tests include enzyme-linked immunosorbent assay (ELISA), modified agglutination test (MAT), and western blot (WB), which are commercially available as rapid test kits. In this study, we evaluated the manufacturer recommended cut-off of ELISA-PrioCHECK test kit and determined a new optimal cut-off for identifying T. gondii infections in pigs. Assessment of the commercial ELISA kit was done by including data from two additional serological tests, MAT, and WB, applied to seven pig population categories with varying prevalences. A total of 233 plasma samples that were previously used in other studies for investigating T. gondii seroprevalence in pigs in Denmark were randomly selected for inclusion, including 95 samples that had previously been analysed with all three tests and an additional 138 samples that were analysed using the three serological tests for this study. In the absence of a gold standard test, a latent class model was fit to the data to obtain estimates of sensitivity and specificity for each of the tests along with prevalence in each of the populations. A cut-off that maximized the sensitivity and specificity of the ELISA test was then selected. The optimal cut-off value for percent of positive control (PP) in ELISA-PrioCHECK was estimated to be 27.7 PP, which is higher than the cut-off value of 20 PP that is recommended by the manufacturer. At this cut-off, the estimated sensitivities of ELISA, MAT and WB were 99.2% (96.3–100.0%), 96.3% (88.0–100.0%), and 89.8% (80.0–98.0%), respectively. The estimated specificities of ELISA, MAT and WB were 95.2% (92.5–97.6%), 99.6% (97.5–100.0%), and 98.2% (95.9–100.0%), respectively. Our findings have broad relevance to the use of the ELISA-PrioCHECK test kit for detecting Toxoplasma gondii infection in pigs.

Expanding syphilis test uptake using rapid dual self-testing for syphilis and HIV among men who have sex with men in China: A multiarm randomized controlled trial.

Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China. An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing. Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested). Chinese Clinical Trial Registry: ChiCTR1900022409.

Health Canada: risk of accidental poisoning from COVID-19 rapid antigen test kits

Health Canada: risk of accidental poisoning from COVID-19 rapid antigen test kits

Burden of Rota Virus Gastroenteritis in Children Under 5 Years of Age

Objective: To detect the burden of Rotavirus gastroenteritis in hospitalized and non-hospitalized children under 5 years of age.&#x0D; Study Design: Retrospective observational study.&#x0D; Place and Duration of Study: Department of Virology, Armed Forces Institute of Pathology, from Jan 2015 to Dec 2019.&#x0D; Methodology: A total of 527 stool samples were analyzed using rapid immunochromatoghraphic testing kit for Rotavirus. Samples were received from both outdoor and indoor children under 5 years of age presenting with diarrheal illness.&#x0D; Results: 197 (37.4%) patients were positive for rotavirus antigen in stool while 330 (62.6%) were negative. Mean age of participants was 13.4 months ± 16.6 (range: 1-60 months). Out of 197 (37.4%) stool samples which were positive for rotavirus antigen, 66 (33.5%) were female children and 131 (66.5%) were male children. Maximum positive rotavirus stool antigen was observed in 0-2 years age-group i.e., 173 (33%) while 24 (4.4%) were positive in 3-5 years age-group, 110 (20.9%) rotavirus positive samples were from Inpatient Department while 87 (16.5%) were received from Outpatient Department.&#x0D; Conclusion: Rotavirus is a frequent cause of viral gastroenteritis in both hospitalized and non-hospitalized children. Maximum positivity is seen in children under 2 years of age.

Assessment of HIV Rapid Test Kits Inventory Management Practice and Challenges in Public Health Facilities of Addis Ababa, Ethiopia.

BackgroundMany people with undiagnosed HIV live in sub-Saharan Africa and vulnerable laboratory systems undermine testing services.MethodsA facility-based mixed-approach cross-sectional study was conducted from January 1 to February 1, 2020. A total of 23 health facilities were included in the study which stratified into hospitals and health centers. Six months of bin card records and request and resupply forms (RRFs) were reviewed. Data were collected through physical inventory, observation, and document review. After the data was imported into the MS Excel 2016 spreadsheet, it was analyzed using SPSS | Version 20 | Software. In addition, 12 semi-structured in-depth interviews were conducted and responses were analysed using a thematic approach.ResultsThe entire health facility had RRF reports and bin card records while the availability of HIV rapid test kits was 75%. More than half, 38 (55.1%) of the bin card records were updated and the average data accuracy of bin cards was 84.1%. The data quality of the RRF reports was determined accurate 18 (78.3%), complete 15 (65.22%), and on-time 7 (30.3%). Sixteen (69.6%) health facilities experienced at least one stock out with an average daily stock out of 4%. The wastage rate was 0.0083%. Only 9 (39.1%) health facilities have fulfilled acceptable storage conditions.ConclusionMost of the health facilities did no longer fulfilled acceptable storage conditions. Similarly, the data quality of most bin card records and RRF reports was poor. This deprived inventory management practice was likely related to supply, staff, and documentation challenges.

Prevalence of Helicobacter pylori infection by rapid urease test among patients with dyspeptic symptoms who underwent upper gastrointestinal endoscopy in a secondary care hospital

Background: Functional dyspepsia is referred to wide spectrum of upper gastrointestinal symptoms which are nonspecific and without organic pathology of upper gastrointestinal tract, and accounts for &gt;60% of patients undergoing upper gastrointestinal endoscopy. The aim of our study was to determine the prevalence of active Helicobacter pylori (H. pylori) infection by retrospective review of patient records using only rapid urease test reports which gives us the magnitude of the H. pylori prevalence.Methods: 200 patients who presented with dyspepsia were studied clinically according to the proforma over a period of 18 months from April 2020 to October 2021, Patients underwent upper gastro-intestinal endoscopy under topical anesthesia, and biopsies were taken from the antrum. Biopsy specimens were immediately placed onto rapid urease test kit containing urea and an indicator. Positive test for H. pylori was confirmed by the change in color of the medium from yellow to pink or red and when the rapid urease test was positive, patient was considered as H. pylori positive.Results: Out of 200 patients, most commonly affected age group are patients between 18-35years and is more in males than females (48:36), 86 patients were found to be H. pylori positive (43%) associated with acid peptic disease and duodenal ulcers, gastric antral ulcers.Conclusions: H. pylori is a potential risk factor of gastric malignancy. After being aware of the prevalence of H. pylori by early detection of active H. pylori infections, rapid urease test serves only as a rapid screening tool in dyspeptic symptoms of patients with acid peptic disease than all other tests.

Prostate Cancer Screening Using a Quick One-Step PSA Test

Background and aim: A one-step prostate-specific antigen (PSA) test was studied in a large population to improve the convenience and lower the cost of prostate cancer (PC) screening. The PSA rapid test kit aids in the diagnosis of PC by detecting human PSA in serum or plasma at or above a threshold level of 4 ng/mL. The aim of this study is to screen PC using a Quick One-Step PSA Test. Materials and Methods: Between July 2020 and August 2021, at National institute of urology and nephrology, Cairo, Egypt, Male attendees were offered PC screening utilizing the PSA quick test. A total of 305 men's blood samples were tested. The test was interpreted by two independent observers. Following that, the remaining serum samples were examined using a standard quantitative technique. Results: Of 305 participants, 118 had a PSA value of less than 4 ng/mL, and 55 presented a PSA value higher than 4 ng/mL. A total of 63 participants had a PSA value between 4 and 10 ng/mL. A total of 12 participants presented a PSA value &gt; 10 ng/mL; 10 was judged as positive. The intensity of the color reaction was implying a strong positive correlation between the two methods (correlation test: P&lt; 0.0001). Conclusion: The one-step test is a good preliminary screening method from which positive results may be quantified to provide a semi-quantitative estimate of the degree of PSA rise. The test is inexpensive, easy to do, and provides results in a timely manner.

Prostate Cancer Screening Using a Quick One-Step PSA Test

Background and aim: A one-step prostate-specific antigen (PSA) test was studied in a large population to improve the convenience and lower the cost of prostate cancer (PC) screening. The PSA rapid test kit aids in the diagnosis of PC by detecting human PSA in serum or plasma at or above a threshold level of 4 ng/mL. The aim of this study is to screen PC using a Quick One-Step PSA Test. Materials and Methods: Between July 2020 and August 2021, at National institute of urology and nephrology, Cairo, Egypt, Male attendees were offered PC screening utilizing the PSA quick test. A total of 305 men's blood samples were tested. The test was interpreted by two independent observers. Following that, the remaining serum samples were examined using a standard quantitative technique. Results: Of 305 participants, 118 had a PSA value of less than 4 ng/mL, and 55 presented a PSA value higher than 4 ng/mL. A total of 63 participants had a PSA value between 4 and 10 ng/mL. A total of 12 participants presented a PSA value &gt; 10 ng/mL; 10 was judged as positive. The intensity of the color reaction was implying a strong positive correlation between the two methods (correlation test: P&lt; 0.0001). Conclusion: The one-step test is a good preliminary screening method from which positive results may be quantified to provide a semi-quantitative estimate of the degree of PSA rise. The test is inexpensive, easy to do, and provides results in a timely manner.

Performance Analysis of Novel Nucleic Acid Detection Kit for Mycoplasma pneumoniae

Respiratory tract infections caused by Mycoplasma pneumoniae is a serious risk for child health. It has been difficult to prevent and control for a variety of reasons; therefore, timely diagnosis is particularly important for treatment of patients. At present, the rapid M pneumoniae test kits based on nucleic acid amplification have been commercialized and used as primary diagnostic tools for M pneumoniae infection, but current kits are time-consuming, which is difficult to meet the requirement for accurate and rapid diagnosis of M pneumoniae during epidemics. Rapid and accurate test kits are urgently required to diagnose M pneumoniae infection. In this article, we evaluated the performance of a novel nucleic acid detection kit (A) for M pneumoniae from feasibility and sensitivity, and compared it with kit B. Results showed this kit has the advantage of being rapid, sensitive, and specific, which meets the demands for the diagnosis of M pneumoniae infection in clinical settings.

Malaria rapid diagnostic test positivity rate among febrile patients seen at the Paediatric emergency unit of a tertiary care facility

Background: Malaria, a life-threatening parasitic disease transmitted to humans by the female Anopheles mosquito is one of the infectious causes of fever in children. In Nigeria, malaria remains one of the most important health problems, accounting for 25% of infants and 30% of under-five mortalities. The objective of this study was to determine the prevalence of malaria among febrile children presenting at the children's emergency room (CHER) of a tertiary health facility in Abakaliki using a malaria rapid diagnostic test (mRDT).&#x0D; Methodology: This was a retrospective study that involved children presenting with fever in CHER over a 3-year period. A total of 1,273 febrile children below 18 years of age were tested with a malaria rapid diagnostic test (mRDT) kit during this period. Medical records of the patients were assessed to retrieve information such as age, gender, and clinical diagnoses. Data were analyzed using SPSS version 25.&#x0D; Results: A total of 707 (55.5%) were males and 883 (69.4%) were below 5 years of age. The overall prevalence of malaria by the mRDT test was 26% (n=331). Uncomplicated malaria, 283 (22.2%) was the commonest clinical diagnosis made while the least was malnutrition 3 (0.2%). Children aged 10-&lt;18 years were predominantly affected as mRDT positivity rate was significantly higher in children age group 10-&lt;18 years (40.4% 76/189) than other age groups (X2=44.76, p&lt;0.001). Similarly, the rate was significantly higher (OR 9.625, 95% CI 7.233-12.808, p&lt;0.0001) in children with the clinical diagnosis of malaria (55.2%, 235/426) than those with the clinical diagnosis of other illnesses (11.3%, 96/847), and significantly higher (OR 0.19, 95% CI 0.1186-0.3043, p&lt;0.0001) among those clinically diagnosed with complicated (79.7%, 114/143) than those with uncomplicated malaria (42.8%, 121/283).&#x0D; Conclusion: There is a high prevalence of malaria among febrile children presenting at the CHER of Alex Ekwueme Federal University Teaching Hospital Abakaliki. Children age group 10-&lt;18 years were predominantly affected. The use of mRDT should be encouraged both as a screening and diagnostic tool with a protocol such that febrile children who have positive results are confirmed as having malaria while those with negative results are further evaluated with microscopy.

POS-905 PROSPECTIVE STUDY ON COVID-19 INFECTION IN KIDNEY TRANSPLANT RECIPIENTS IN SABAH: A PRELIMINARY RESULT

In December 2019, a new strain of coronavirus, later named as COVID-19, was identified in Wuhan, Hubei Province, China and has since become a worldwide pandemic. There is paucity of literature on the clinical progression and outcome of kidney transplant recipients diagnosed with COVID-19. We aim to determine the clinical features, management and outcomes of COVID-19 in kidney transplant recipients This is a prospective cohort study from 1 December 2020 - 31 December 2021. All kidney transplant recipients age more than 18 years old diagnosed with COVID-19 infection, by reverse transcriptase polymerase chain reaction or rapid test kit for COVID-19 antigen, will be admitted and followed up throughout admission with clinical, laboratory data and outcomes recorded. There were a total of 7 cases of COVID-19 infection in kidney transplant recipients up until 15 September 2021. Six were males and 1 female with mean age of 52.1 years old (SD 13.2) and admission median creatinine of 124 υmol/L (IQR 46). Two patients had new-onset-diabetes mellitus after transplant (28.6%) while 4 (57.1%) had hypertension. Majority (n=6, 86%) had oral prednisolone, mycophenolate mofetil and tacrolimus as baseline immunosuppressants. Only 2 patients (28.6%) were not vaccinated while the rest were fully vaccinated with BNT162b2 where the mean days to COVID-19 infection following vaccination was 85 days. Majority (n=6, 85%) presented with respiratory symptoms such as fever, cough and/or myalgia. On presentation, 3 patients (42.9%) were diagnosed with severe illness requiring oxygen support, 2 patients (28.6%) had moderate illness, 1 (14.3%) was of mild illness and 1 was asymptomatic. Four patients (57%) developed acute kidney injury where 1 patient required hemodialysis. Three patients (42.9%) required intensive care management. Throughout the hospitalisation, 1 patient deteriorated and was ventilated while 2 required high flow nasal cannula, and another 2 required face mask oxygen support. Only 2 patients required no oxygen support throughout admission. Antimetabolite immunosuppressant was withheld for all 7 patients and patients requiring oxygen therapy (n=5) received intravenous methylprednisolone ranging from 3-7 days. Two patients received intravenous tocilizumab while 1 received oral baricitinib for additional treatment of critical COVID-19 infection. Higher admission c-reactive protein level predicts more severe COVID-19 infection (p=0.019), while age, creatinine, albumin, ferritin and vaccination status were not statistically significant in predicting severity of COVID-19. As of now, 5 patients were discharged well, 1 died due to COVID-19 complications, and 1 patient is still under intensive care giving the mortality rate of 14.3% in Sabah. This case series showed that despite being fully vaccinated, 4 out of 5 patients still suffered from severe and critically ill COVID-19 infection with 1 death making the mortality rate of 20% amongst the vaccinated group. This may be due to suboptimal antibody response in kidney transplant recipients following vaccination. Safety measures with good hand hygiene, social distancing and face mask are still critical to prevent disease transmission for kidney transplant recipient. Our report revealed that kidney transplant recipient is at risks of severe COVID-19 infection with high mortality despite being vaccinated.

Validation of rapid antibody (IgG-IgM) test kit for SARS-CoV-2 infection in Qatar.

Background: In response to the growing coronavirus disease 2019 (COVID-19) pandemic and the shortage of laboratory based molecular testing capacity and reagents, multiple diagnostic test manufacturers have developed rapid and easy to use devices to facilitate testing outside laboratory settings. These kits are either based on detection of proteins from SARS-CoV-2 virus or detection of antigen or human antibodies generated in response to the infection. However, it is important to understand their performance characteristics and they must be validated in the local population setting.Design and methods: The objective is to assess the validity of the rapid test for IgG and IgM immunoglobulins compared to the current gold standard reverse transcription polymerase chain reaction (RT-PCR) test. A total of 16951 asymptomatic individuals were tested by the Ministry of Public Health track-and-trace team using both rapid immunodiagnostic test and RT-PCR as part of screening across various random settings with potential risk of community interaction prior to gradual lifting of restrictions in Qatar. Rapid test was considered to be posiive if both IgG and IgM are positive, while only IgG/IgM positive was considered as rapid test negative. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated.Results: The sensitivity of rapid test kit was found to be 0.9%, whereas the specificity was found to be 97.8%. the PPV was found to be 0.3% whereas the NPV was found to be 99.4%.Conclusions: Based on the outcome and results of the study, it appears that the sensitivity and PPV of the rapid antibody test are low. As such, this test is not recommended for use to assist in taking clinic-based decisions or decisions related to quarantine/isolation. Significance for public health It is important to understand the performance characteristics of the Rapid Antibody (IgG-IgM) kits and they must be validated in the local population setting before they can be recommended for use.

Prevalence of Hepatitis-B virus and HIV infections in Pregnant Women Receiving Antenatal Care Services, Kano – Nigeria

The dreadful nature of hepatitis-B virus (HBV) and HIV infections and their common mode of transmission during pregnancy have made them become an important global health problem and a leading cause of maternal complications and neonatal deaths in both developed and developing countries. The current study determined the seroprevalence of HBV and HIV amongst pregnant women receiving antenatal care services in Kano state. Structured questionnaires were distributed to 276 (14-49 years) consenting pregnant women across the six selected health facilities to obtain demographic and socio-economic data. Three (3) ml of venous blood sample were drawn by venipuncture and centrifuged at 3000 rpm for 5 min. The serum was tested for the presence of HIV antibodies using the Abbott Determine HIV 1/2 test kit and HBV antibodies using a rapid diagnostic test kit (DiaSpot Diagnostics, USA). The \chi2 test for independence was determined using GraphPad InStat software (version 3.0). Sociodemographic characteristics of the respondents showed 95.7% of the respondents as being married, 64.5% lived in a monogamous family, 62.4% petty traders, 26.8% unemployed, 57.4% of them are 21 – 30 years of age, 41.3% have Quranic education, 28.3% are 1st gravida while 36.9% have more than 4 children. Additionally, 1.4% of HIV and 8% of HBV cases were confirmed. The chi-squared test for independence (\chi2=13.078, P=0.0003) showed a significant relationship between the two variables. HIV and HBV infections existed in the study group. Regular screening, awareness, and health education programs on the mode of their transmission should be directed to pregnant women to prevent vertical transmission.

Serologic evidence of exposure to Human Immunodeficiency Virus Type 1 and Dengue Virus among patients attending diagnostic Laboratory, Lagos State, Nigeria

Reportedly, in co-infection, dengue viral (DENV) replication negatively impacts human immunodeficiency virus type 1 (HIV-1). Reports on this or on people having dual HIV-1/DENV are however, scarce in Nigeria, where both HIV-1 and DENV are endemic. As a preliminary investigation in southwest Nigeria, we hypothesized that a high proportion of individuals presented for laboratory tests have serologic evidence of dual HIV-1/DENV infection. This is a cross-sectional Research Institute-based serologic study; patients attending a specific Clinical Diagnostic Laboratory in Lagos State were enrolled. Plasma samples (n=150) of consenting asymptomatic patients were serially screened for evidence of HIV-1 antibodies using DETERMINETM and UNI-GOLDTM HIV-1/-2 rapid test kits. Only the samples (n=54) confirmed HIV-1 reactive by the latter (and some randomly selected non-reactive samples [n=37]) were tested with ELISA kit for anti-DENV immunoglobulin G (IgG) antibodies. Microsoft Excel and Statistical Package for the Social Sciences were used for statistical analysis. Some participants had detectable HIV-1/DENV antibodies with dual positivity rate of 16.5% [as group-specific point-prevalence rate]. This was independently associated (p=0.04) with marital status as participants who were neither single nor married (categorized as ‘others’) had more than 11 times (OR: 11.3) likelihood of being dual seropositive. Mono-positivity of HIV-1 antibody among the 91 participants tested for dual HIV-1/DENV seropositivity was 59.3%; corresponding rate for DENV antibody was 20.9%. As per mono-positivity rates, the likelihood of participants testing positive to HIV-1 antibody was more than 21 times (Odds ratio [OR]: 21.3) that of DENV antibody. In conclusion, 15 participants (16.5%) of this specific group had serologic evidence of dual HIV-1/DENV infection; this we considered low given the endemicity of Nigeria for both viruses. As a subpopulation with unusually high HIV-1 mono-positivity; thelow DENV mono-positivity might be responsible for the low dual HIV-1/DENV positivity.

User experience of home-based AbC-19 SARS-CoV-2 antibody rapid lateral flow immunoassay test

The urgent need to scale up testing capacity during the COVID-19 pandemic has prompted the rapid development of point-of-care diagnostic tools such as lateral flow immunoassays (LFIA) for large-scale community-based rapid testing. However, studies of how the general public perform when using LFIA tests in different environmental settings are scarce. This user experience (UX) study of 264 participants in Northern Ireland aimed to gather a better understanding of how self-administered LFIA tests were performed by the general public at home. The UX performance was assessed via analysis of a post-test questionnaire including 30 polar questions and 11 7-point Likert scale questions, which covers the multidimensional aspects of UX in terms of ease of use, effectiveness, efficiency, accuracy and satisfaction. Results show that 96.6% of participants completed the test with an overall average UX score of 95.27% [95% confidence interval (CI) 92.71–97.83%], which suggests a good degree of user experience and effectiveness. Efficiency was assessed based on the use of physical resources and human support received, together with the mental effort of self-administering the test measured via NASA Task Load Index (TLX). The results for six TLX subscales show that the participants scored the test highest for mental demand and lowest for physical demand, but the average TLX score suggests that the general public have a relatively low level of mental workload when using LFIA self-testing at home. Five printed LFIA testing results (i.e. the ‘simulated’ results) were used as the ground truth to assess the participant’s performance in interpreting the test results. The overall agreement (accuracy) was 80.63% [95% CI 75.21–86.05%] with a Kappa score 0.67 [95% CI 0.58–0.75] indicating substantial agreement. The users scored lower in confidence when interpreting test results that were weak positive cases (due to the relatively low signal intensity in the test-line) compared to strong positive cases. The end-users also found that the kit was easier to use than they expected (p < 0.001) and 231 of 264 (87.5%) reported that the test kit would meet their requirements if they needed an antibody testing kit. The overall findings provide an insight into the opportunities for improving the design of self-administered SARS-CoV-2 antibody testing kits for the general public and to inform protocols for future UX studies of LFIA rapid test kits.

Performance, proficiency, and training need of para-vets in the four states of India

In constrained availability of veterinarians and paramount study on the effectiveness of para-veterinary services, assessing the ability of these personnel vis-à-vis role proficiency and performance from stakeholder's perspective could act as impetus in reforming the animal healthcare and animal husbandry extension delivery system in India. The present study was conducted in four districts of Haryana, Uttar Pradesh, Maharashtra, and Rajasthan respectively. A total of 380 respondents were surveyed, comprising of 160 dairy farmers, 160 para-vets, and 60 veterinarians. Two indices namely, Role Performance Index and Role Proficiency Index were exclusively designed. Based upon the responses, the training need of para-vets were analyzed from the perspective of veterinarians. Accountability for reporting for vaccine failure to higher authority, on-spot health hazard reduction by consulting vets in the uncommon situation and, dissemination of new tools and techniques to farmers (eg. CMT toolkit) were found low by 93.12, 86.62, 91.25% para-vets respectively. Nearly half of para-vets rated their proficiency in the medium category on the role proficiency index, followed by 36.25% in the low category towards the assessed roles. Veterinarians perceived high training needs for quarantine measures (93.33%), fodder production and silage making (88.34%), latest trends in animal breeding, feeding and reproductive management (91.67%), awareness about principles of animal management and disease control (83.34%), sufficient information about rapid test kits (73.33%), and knowledge about new technologies in Animal Husbandry evolved by research institutions (86.67%). Paraveterinary services were most skillful in Hisar district, followed by Jaipur and Ahmadnagar district, and least proficient in Mathura district.

Ag3PO4/Ag nanocomposite for selective and sensitive cyanide determination in food samples through catalytical colorimetry using a paper-based test kit

A paper-based test kit for selective and sensitive determination of cyanide was successfully developed using a Ag3PO4/Ag nanocomposite for catalytic colorimetry. The Ag3PO4/Ag nanocomposite synthesized via a one-step chemical bath method could instantly oxidize the chromogenic substrate ABTS for the color development under acidic conditions without the requirement of H2O2. During the detection step, cyanide in the sample was converted into gaseous hydrogen cyanide (HCN) using sulfuric acid. The HCN species then reacted with the generated Ag+ species via coordinate covalent bonding to form silver cyanide complex ions [Ag (CN2)]-. The amount of Ag+ species used for oxidizing ABTS subsequently decreased and so did the color intensity on the paper-based test kit. Specifically, the color intensity decreased with increasing cyanide concentrations in the range of 2.50–20.0 mg L−1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.48 mg L−1 and 1.59 mg L−1, respectively. The developed test kit showed relatively high selectivity towards cyanide and high tolerance towards other cations and anions present in real samples. When applied to real samples including fruit juices and food products, the performance of the rapid and low-cost test kit was well validated by a conventional precipitation titration method.

Common hepatitis B virus genotypes among blood donors in Lagos, Nigeria.

Hepatitis B virus (HBV) infection is one of the public health diseases causing global health problems. It is a leading cause of cirrhosis and hepatocellular carcinoma. Blood transfusion is a major route of its transmission and screening of blood is suboptimal in our environment. Occult HBV infection describes the presence of HBV DNA in blood or liver tissue in patients who are hepatitis B surface antigen (HBsAg) seronegative. This study documented the common genotypes of HBV a blood-borne infection in the population of blood donors in Lagos. This was a cross-sectional study carried out at the blood donor clinics of ten Lagos State Government-owned hospitals in Lagos State. A total of 1400 participants were recruited consecutively from November 2020 to June 2021. All participants' samples were screened using Diaspot Rapid Test Kit (RTK) and Dialabenzyme enzyme-linked immunosorbent assay (ELISA) kit. Furthermore, some of the plasma samples were used for HBV DNA extraction and genotyping using the real time-polymerase chain reaction. Statistical analysis was carried out using the Statistical Package for the Social Sciences (SPSS) software version 26 and P value was considered significant at ≤0.05. The sero-prevalence of HBsAg using RTK and ELISA was 19.9% and 22.4%, respectively. The prevalence of occult HBV infection was 5.2%. A total of 278 and 313 HBsAg RTK and ELISA positive samples were obtained, respectively. HBV genotype result had A (46.6%) as the most prevalent followed closely by B (44.7%), E (23.8%), D (20.9%) and C (11.2%). HBV infection has a high prevalence among blood donors. ELISA is a more sensitive screening tool and its use should be advocated nationally. HBV genotype A is the most prevalent genotype from our study.