Rapid Serological Tests Research Articles

Rapid Serological Test for COVID-19, One-Step-COVID-2019: Accuracy and Implications for Pandemic Control

Background: Accurate and rapid testing for COVID-19 is critical for effective disease management and control. The One-Step-COVID-2019-Test was developed as a rapid serological test to detect antibodies against SARS-CoV-2. Objective: To estimate the accuracy of the rapid serological test for COVID-19 using One-Step-COVID-2019. Methods: We conducted a population-based serological survey with a stratified sampling of 593 adults between October and December 2020, prior to mass vaccination and during a period of limited availability of rapid tests. Participants provided 7.5 mL of serum, which was tested using the One-Step-COVID-2019-Test for IgM-IgG antibodies without distinction, as well as an in-house ELISA for IgG against the spike protein. Statistical analysis accounted for sampling weights, with accuracy assessed through sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), Youden index, and kappa coefficient, using ELISA as the reference standard. McNemar’s test identified significant differences between the test results. Results: The ELISA-based prevalence of infection was 11.1%. The One-Step-COVID-2019-Test showed low sensitivity (27.0–30.8%) but high specificity (89.9–96.6%), with poor agreement (kappa: 0.290–0.337), particularly among asymptomatic individuals. Conclusions: The One-Step-COVID-2019 rapid test for COVID-19 demonstrated inadequate performance, characterized by low sensitivity and poor reliability, making it unsuitable for effective serological surveillance.

Illicit Fentanyl Use and Hepatitis C Virus Seroconversion Among People Who Inject Drugs in Tijuana and San Diego: Results From a Binational Cohort Study.

Illicitly manufactured fentanyl (IMF) increases overdose mortality, but its role in infectious disease transmission is unknown. We examined whether IMF use predicts hepatitis C virus (HCV) and human immunodeficiency virus (HIV) incidence among a cohort of people who inject drugs (PWID) in San Diego, California and Tijuana, Mexico. PWID were recruited during 2020-2022, undergoing semi-annual interviewer-administered surveys and HIV and HCV serological rapid tests through 2024. Cox regression was conducted to examine predictors of seroconversion considering self-reported IMF use as a 6-month lagged, time-dependent covariate. Of 398 PWID at baseline, 67% resided in San Diego, 70% were male, median age was 43 years, 42% reported receptive needle sharing, and 25% reported using IMF. HCV incidence was 14.26 per 100 person-years (95% confidence interval [CI]: 11.49-17.02), and HIV incidence was 1.29 (95% CI: .49-2.10). IMF was associated with HCV seroconversion, with a univariable hazard ratio (HR) of 1.64 (95% CI: 1.09-2.40), and multivariable HR of 1.57 (95% CI: 1.03-2.40). The direction of the relationship with HIV was similar, albeit not significant (HR 2.39; 95% CI: .66-8.64). We document a novel association between IMF and HCV seroconversion among PWID in Tijuana-San Diego. Few HIV seroconversions (n = 10) precluded our ability to assess if a similar relationship held for HIV. IMF's short half-life may destabilize PWID-increasing the need for repeat dosing and sharing smoking materials and syringes. New preventive care approaches may reduce HCV transmission in the fentanyl era.

THE STUDY OF PERFORMANCE AND DIAGNOSTIC EFFICACY OF WIDAL TEST AND STOOL CULTURE IN THE DIAGNOSIS OF TYPHOID FEVER AMONG SUSPECTED PATIENTS IN LOW INCOME COUNTRIES : A COMPREHENSIVE SYSTEMATIC REVIEW

Background: Typhoid fever is a significant health challenge in low- and middle-income countries (LMIC) due to inadequate access to clean water and sanitation infrastructure. The prevalence of typhoid fever, as determined by the Widal test, has quadrupled between 2014 and 2018, with sub-Saharan Africa having the highest infection load. Inadequate diagnosis and treatment are crucial to prevent complications. Rapid serological tests, lack of standard laboratory practices, and limited disease surveillance systems contribute to the uncertainty in disease burden. Methods: Following PRISMA 2020 guidelines, this systematic review concentrated on full-text English literature published between 2014 and 2024. Editorials and review articles that appeared in the same journal as the submission were not accepted without a DOI. The literature was assembled using a variety of online databases, including ScienceDirect, PubMed, and SagePub. Result: Utilizing reliable resources including Science Direct, SagePub, and PubMed, the study examined around 800 papers. After seven pieces were determined to be relevant for methodical investigation, a more thorough examination of the complete material was conducted. Conclusion: Diagnostics for typhoid fever, a common illness in low- and middle-income countries, mostly depend on the Widal test. On the other hand, variables such as malaria parasitemia, antigen standardization, and patient population affect how accurate the test is. The suggested diagnostic strategy identifies Salmonella from blood, stool, and bone marrow cultures; this calls for significant upgrades to laboratory resources as well as continuous training.

HIV seroconversion and associated factors among seronegative pregnant women attending ANC in Ethiopia: an institution-based cross-sectional study.

In countries with limited resources, including Ethiopia, HIV is diagnosed using a rapid serological test, which does not detect the infection during the window period. Pregnant women who test negative for HIV on the first test may seroconvert throughout pregnancy. Women who are seroconverted during pregnancy may not have received interventions, as they are considered HIV-negative unless they are retested for HIV at the end of their pregnancy. Due to limited data on HIV seroconversion, this study aimed to measure the extent of HIV seroconversion and to identify associated factors among seronegative pregnant women attending ANC in Ethiopia. Institution-based cross-sectional study was conducted among HIV-negative pregnant women attending the ANC in Ethiopia between June and July 2020. Socio-demographic, clinical, and behavioral data were collected through face-to-face questionnaires and participants' records review. HIV retesting was performed to determine the current HIV status of pregnant women. The data collected were entered into Epi data version 4.4.1 and were exported and analyzed by SPSS version 25. A p-value < 0.25 in the bivariate analysis was entered into multivariable logistic regression analysis and a p-value of < 0.05 was considered statistically significant. Of the 494 pregnant women who tested negative for HIV on their first ANC test, six (1.2%) tested positive on repeat testing. Upon multivariable logistic regression, pregnant women who have had a reported history of sexually transmitted infections [AOR = 7.98; 95% CI (1.21, 52.82)], participants' partners reported travel history for work frequently [AOR = 6.00; 95% CI (1.09, 32.99)], and sexually abused pregnant women [AOR = 7.82; 95% CI (1.194, 51.24)] were significantly associated with HIV seroconversion. The seroconversion rate in this study indicates that pregnant women who are HIV-negative in early pregnancy are at an ongoing risk of seroconversion throughout their pregnancy. Thus, this study highlights the benefit of a repeat HIV testing strategy in late pregnancy, particularly when the risk of seroconversion or new infection cannot be convincingly excluded. Therefore, repeated testing of HIV-negative pregnant women in late pregnancy provides an opportunity to detect seroconverted pregnant women to enable the timely use of ART to prevent mother-to-child transmission of HIV infection.

Comparative evaluation of four rapid diagnostic tests that detect human Trypanosoma cruzi-specific antibodies to support diagnosis of Chagas Disease in urban population of Argentina.

Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is the most important endemic anthropozoonosis in Argentina. Since 2010, the World Health Organization has highlighted the urgent need to validate diagnostic systems that allow rapid detection of T. cruzi, infection in primary healthcare centers. Serological rapid diagnostic tests (RDTs) for T. cruzi, infection could be used to improve case management, as RDTs do not require specialized laboratories or highly trained staff to use them. We aimed to generate unbiased performance data of RDTs in Argentina, to evaluate their usefulness for improving T. cruzi, diagnosis rates. This is a retrospective, laboratory-based, diagnostic evaluation study to estimate the clinical sensitivity/specificity of four commercially available RDTs for T. cruzi, using the Chagas disease diagnostic algorithm currently used in Argentina as the reference standard. In total, 400 serum samples were tested, 200 from individuals with chronic T. cruzi infection and 200 from individuals not infected with T. cruzi. All results were registered as the agreement of at least two operators who were blinded to the reference standard results. The sensitivity estimates ranged from 92.5-100% (95% confidence interval (CI) lower bound 87.9-98.2%); for specificity, the range was 76-96% (95% CI lower bound 69.5-92.3%). Most RDTs evaluated showed performances comparable with the reference standard method, showing almost perfect concordance (Kappa 0.76-0.92). Our study demonstrates that, under controlled laboratory conditions, commercially available RDTs for CD have a performance comparable to the Argentinian diagnostic algorithm, which is based on laboratory-based serological tests. For the next stage of our work, the RDTs will be evaluated in real-world settings.

Prevalence of neutralizing antibodies against SARS-CoV-2 using a rapid serological test in health workers of a Spanish Department of Health in Alicante (Spain) before the booster dose of the vaccine

AimTo study the prevalence of neutralizing antibodies in healthcare workers and healthcare support personnel after the administration of the second dose of the BNT162b2 vaccine (Pfizer-BioNTech). Materials and MethodsIn December 2021, we undertook a study in the Health Department in Orihuela, Alicante (Spain), which consists of 1500 workers. We collected demographic variables about the study participants, and we performed a “point-of-care” immunochromatography test to measure the presence of neutralizing antibodies (OJABIO® SARS-CoV-2 Neutralizing Antibody Detection Kit, manufactured by Wenzhou OJA Biotechnology Co., Ltd. Wenzhou, Zhejiang, China) before the administration of the third dose of the vaccine. ResultsWe obtained complete information about 964 (64%) workers, which consisted of 290 men and 674 women. The average age was 45,8 years (min. 18, max. 68) and the average time since the last dose of the vaccine was 40,5 weeks (min. 1,71, max. 47,71). A total of 131 participants (13,5%) had suffered infection by SARS-CoV-2 confirmed using RT-PCR. The proportion of participants who showed presence of neutralizing antibodies was 38,5%. In the multivariable analysis, the time since the last dose of the vaccine (aOR week: 1,07; 95%CI: 1,04; 1,09) and previous infection by SARS-CoV-2 (aOR: 3,7; 95CI: 2,39; 5,63) showed a statistically significant association with the presence of neutralizing antibodies. ConclusionsThe time since the administration of the last dose of the vaccine and the previous infection by SARS-CoV-2 determined the presence of neutralizing antibodies in 38,5% of the healthcare workers and support workers.

ASSESSMENT OF THE ACCURACY OF THE RAPID TEST FOR THE DIAGNOSIS OF HELICOBACTER PYLORI IN PATIENTS THAT DIDN'T UNDERGO PREVIOUS ERADICATION THERAPY AND WHO WENT THROUGH ENDOSCOPY.

Helicobacter pylori infection is widely spread globally and is known to cause potentially serious diseases. Several diagnostic methods exist to identify and treat carriers of this bacterium. Serological tests for the diagnosis of infection are based on the detection of antibodies immunoglobulin G against H. pylori, a non-invasive, inexpensive, and easy-to-perform option. This research aims to ascertain the accuracy of an immunochromatographic serological test to verify the feasibility of using this method in patients who have not undergone previous eradication therapy. Rapid tests and questionnaires were applied to 53 patients that underwent upper digestive endoscopy with research for H. pylori between the period of September and October 2021. The results were compared with histopathology. In the rapid tests, seven positive and 46 negative results were obtained. When compared with the gold stan-dard, the following values were described: sensitivity 54.5%, specificity 97.6%, positive predictive value 85.7%, and negative predictive value 89.1%. In the present study, the immunochromatographic serological tests had an accuracy close to the values found in other similar studies. Therefore, it may be concluded that the rapid serological test remains a reasonable choice for screening large populations due to its low cost and ease of application, especially in those individuals who have not undergone previous treatment. • Helicobacter pylori infection can cause potentially serious diseases. • Serological tests are based on the detection of antibodies immunoglobulin G against Helicobacter pylori. • Serological tests for the diagnosis of Helicobacter pylori infection are low cost tools and have easy application. • Rapid serological test is a reasonable choice for screening large populations.

Comparative Study of Some Staining Methods for the Demonstration of Helicobacter pylori in Gastric Biopsies in Gombe State, Nigeria

Background: Currently there are different staining methods available for the demonstration of Helicobacter pylori in gastric biopsies sections. Most of these methods are technically demanding, slow and expensive with varying sensitivity and specificity. Aims: This study was to compare some of these techniques for the detection of H. pylori in routine gastric biopsy tissue sections in order to ascertain their reliability and effectiveness. Methodology: Sixty-five positive and seven negative cases of H. pylori were selected based on the results of rapid urease test, serology test and histopathological examination of the tissue sections. Histopathological examinations of sections stained by Hematoxylin and Eosin staining method (H&amp;E), Giemsa staining method, modified Giemsa staining method, modified McMullen staining method and immunohistochemical staining were performed. Results: The sections were evaluated by two independent observers. The sensitivity and specificity for the techniques were as follow: immunohistochemistry, 100% and 100%; modified Giemsa stain, 96.9% and 85.7%; Giemsa stain, 92.3% and 81.4%; modified McMullen stain, 89.2% and 52.9%; H&amp;E, 90.8% and 77.1%. The interobserver agreement was analyzed by Kappa (k) statistics using SPSS version 23 software. The agreement between the two observers was k: 0.859 (98.4%) for immunohistochemistry; k: 0.777 (96.9%) for modified Giemsa stain; k: 0.533 (95.2%) for Giemsa stain; k: 0.267 (92.1%) for modified McMullen stain; and k: 0.421 (93.7%) for H&amp;E stain. Conclusion: The best results were obtained by the immunohistochemical staining and the Giemsa stainings. Although the immunohistochemistry staining method gives the best result and is very reliable, but it is fairly time consuming and expensive. Therefore, considering the cost, applicability and the reliability of the modified Giemsa or Giemsa stain, we recommend both for the detection of H. pylori in gastric biopsies sections especially in resource constrained laboratories.

Is there still yaws in Nigeria? Active case search in endemic areas of southern Nigeria.

Yaws is a disease caused by the bacteria Treponema pallidum subspecies pertenue, which is most commonly seen among children below 15 years. In the twentieth century yaws was endemic in Nigeria but eradication strategies markedly reduced the disease burden. Currently there is minimal data on the ongoing transmission of yaws in Nigeria, despite reports of confirmed yaws cases in neighbouring West African countries. We conducted both community and school-based active yaws case search among school-aged children in southeast Nigeria. Children were screened by trained community volunteers. Suspected yaws cases were clinically reviewed and tested using rapid diagnostic serological tests. Between February and May 2021, up to 28 trained community volunteers screened a total of 105,015 school children for yaws. Overall, 7,706 children with various skin lesions were identified. Eight (8) suspected cases of yaws were reported, reviewed and screened, but none was confirmed using rapid diagnostic tests. The four most common skin conditions identified were scabies (39%), papular urticaria (29%), tinea corporis (14%) and tinea capitis (12%). No case of yaws was confirmed in this large population of children in south-east Nigeria. Continuous community awareness and yaws case finding activities have been recommended across Nigeria.

Approaches to produce and characterize recombinant protein VP1-2A of HAV for serological rapid test application

Studies reporting the expression of hepatitis A virus (HAV) structural proteins, specifically recombinant VP1-2A containing an immunogenic activity, use the Escherichia coli system. Recombinant HAV proteins may represent a source of less expensive antigens for application in different diagnostic platforms. However, the formation of insoluble aggregates is an obstacle to obtaining large amounts of HAV proteins in their native form. To overcome this obstacle, some approaches were applied in this study to improve purification, solubility, and protein expression levels. Critical properties were evaluated. The introduction of another insertion codon to increase the protein concentration and vector activity was observed and verified by SDS-PAGE. The expression was established with 0.4 mM IPTG for 4 h at 37 °C. The VP1 protein was partially soluble at an isoeletric point (pI) of 6.45. The majority of HAV VP1-2A proteins measured 45.19 kDa in size and had a homogeneity of 53.58%. Multi-antigen print immunoassay (MAPIA) showed antigenicity at different HAV VP1-2A concentrations, and microsphere-based immunoassays showed a specificity of 100% and a sensitivity of 84%. HAV VP1-2A was characterized using different sensitivity methods to prove its biological activity, indicating its use as a tool for the diagnosis of Hepatitis A virus infection.

Silent SARS-CoV-2 infection: seroprevalence study of SARS-CoV-2 anti- nucleocapsid IgG antibodies in Kragujevac, Serbia

Serological testing is a powerful tool for analyzing the infectious disease burden landscape. Therefore, this study aimed to determine the seroprevalence against SARS-CoV-2 in the population of the municipality of Kragujevac, Serbia, with a particular reference to silent infections. A total of 4,804 participants over 19 years of age were randomly sampled for population-based seroprevalence research. Anti-N IgG antibodies were measured using rapid serological tests (UNscience®). The population was divided into four Cohorts, according to the history of SARS-CoV-2 infection and vaccination status with the whole inactivated virus vaccine BBIBP-CorV (Vero Cell®, Sinopharm), as follows: Cohort I—confirmed SARS-CoV-2 infection, not vaccinated with the BBIBP-CorV vaccine; Cohort II—without confirmed SARS- CoV-2 infection, vaccinated with the BBIBP-CorV vaccine; Cohort III—confirmed SARS-CoV-2 infection, vaccinated with the BBIBP-CorV vaccine; Cohort IV—without confirmed SARS-CoV-2 infection, not vaccinated with the BBIBP-CorV vaccine (silent immunization). Cohorts I and IV included patients vaccinated with vaccines other than the BBIBP-CorV vaccine. The results showed that the overall prevalence of anti-N IgG antibodies was 56.5%, with the highest seroprevalence in Cohort III at 85.8%. In Cohort IV, the prevalence of anti-N IgG antibodies was 40.7%, attributed to silent immunization. The results also suggest that the prevalence of anti-N IgG antibodies decreased over time but remained detectable for more than 12 months in Cohort I. Since currently, there is no data on silent infection frequency in our country, these findings may provide insight into the extent of silent infections in the Serbian population.

Rapid Serologic Test for Diagnosis of Yaws in Patients with Suspicious Skin Ulcers

Rapid Serologic Test for Diagnosis of Yaws in Patients with Suspicious Skin Ulcers

Seroprevalence of COVID-19 in Oran: Cross-Sectional Study.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was introduced in Algeria in March 2020. This study aimed to estimate the seroprevalence of SARS-CoV-2 infection in Oran, Algeria, and to identify factors associated with seropositivity. This was a cross-sectional seroprevalence study conducted between 7 and 20 January 2021 across all 26 municipalities in the province of Oran. The study employed a random cluster sampling technique stratified by age and sex to select participants from households, who were then administered a rapid serological test. The overall seroprevalence and specific seroprevalences by municipality were calculated, and the number of COVID-19 cases in Oran was estimated. The correlation between population density and seroprevalence was also examined. Among the participants, 422 (35.6%; 95% confidence interval [CI], 32.9 to 38.4) had a positive serological test for SARS-CoV-2, and eight municipalities had seroprevalence rates above 73%. We found a strong positive correlation between population density and seroprevalence (r = 0.795, P < 0.001), indicating that areas with higher population density had higher numbers of positive COVID-19 cases. Our study provides evidence of a high seroprevalence of SARS-CoV-2 infection in Oran, Algeria. The estimated number of cases based on seroprevalence is much higher than the number of cases confirmed by PCR. Our findings suggest that a large proportion of the population has been infected with SARS-CoV-2, highlighting the need for continued surveillance and control measures to prevent further spread of the virus. IMPORTANCE This is the first and only seroprevalence study of COVID-19 conducted in the general population in Algeria prior to the national vaccination campaign against COVID-19. The significance of this study lies in its contribution to our understanding of the spread of the virus in the population before the implementation of the vaccination program.

Rapid Immune Tests SARS-COV-2 – An Experience in Beira Baixa

Introduction: SARS-CoV-2 affects the epithelial cells of the respiratory tract, causing severe infections. Since it is a pathology with a high level of transmissibility, it becomes central to mass testing. In addition, there was also a need to monitor the epidemic through serological tests. Objective: Evaluate the presence of antibodies against SARS-CoV-2 in the community residing in Beira Baixa through immunological screening tests. Materials and methods: Analytical, cross-sectional, and observational study, whose sample consists of 206 individuals. Data collection took place between February and April 2021, in the laboratories of the Dr. Lopes Dias Higher School of Health. Verbal informed consent, a questionnaire to collect sociodemographic data and the serological test were applied. Results: Of the total number of participants, 15.5% admitted to having had COVID-19, of which 0.5% suspected they had been infected and 84% said they had never been infected. Regarding the presence of antibodies, 2.9% of the tests performed were positive for the presence of IgM's while 30.1% were positive for the presence of IgG's. Regarding vaccination, at the time of the investigation only 10.2% of the participants were vaccinated, of which 9.7% had IgG antibodies. Conclusion: Rapid serological tests can provide information about the presence of antibodies to SARS-CoV-2, thus being a very advantageous tool for immunity studies.

Use of In-Clinic Diagnostic Kits for the Detection of Seropositivity to Leishmania infantum and Other Major Vector-Borne Pathogens in Healthy Dogs.

Canine Vector-Borne Diseases (CVBDs) are widespread in Europe and enzootic in many other countries. Though severe illnesses may occur, dogs living in enzootic areas often show vague or no clinical signs of CVBDs. Undiagnosed infections/co-infections in subclinically infected animals favor the spread of CVBDs and increase the risk of transmission to other animals and, in some cases, humans. This study has evaluated the exposure of dogs living in key enzootic countries, i.e., Italy and Greece, to major CVBDs via the use of in-clinic diagnostic kits. Overall, 300 privately owned dogs without/with single mild clinical signs living in different regions of Italy (n. 150) and Greece (n. 150) were included in the study. As part of a clinical examination, a blood sample was collected from each dog and subjected to two serological rapid tests, i.e., the SNAP® 4Dx®Plus (IDEXX Laboratories Inc.) for the detection of antibodies against Ehrlichia spp., Anaplasma spp., Borrelia burgdorferi s.l. and Dirofilaria immitis antigen and the SNAP®Leishmania (IDEXX Laboratories Inc.) for the detection of antibodies against Leishmania infantum. In all, 51 dogs (17%; 95% CI 12.9-21.7) were seropositive to at least 1 pathogen, i.e., 4 in Italy (2.7%; 95% CI 1.4-13.1) and 47 in Greece (31.3%; 95% CI 24-39.4). Dirofilaria immitis antigens were found in 39 dogs (13%; 95% CI 9.4-17.3), while antibodies against Ehrlichia, Anaplasma and Leishmania were detected in 25 (8.3%; 95% CI 5.5-12.1), 8 (2.7%; 95% CI 1.2-5.2) and 5 (1.7%; 95% CI 0.5-3.8) dogs, respectively. None of the dogs tested seropositive for B. burgdorferi s.l. Statistical analyses were performed to evaluate associations between exposure to CVBDs and possible risk factors. The present results indicate that dogs living in enzootic areas may be seropositive for one or more CVBDs in absence of clinical signs. Rapid kits are among first line tools for the detection of CVBDs in clinical settings, as they are cost-effective, straightforward and quick to use. Also, in-clinic tests used herein allowed detection of co-exposure to CVBDs investigated.

Diagnosis of helicobacter pylori infection in low out-outcome country: Rapid urease test, serological test, versus direct microbiological examination with gram staining

Introduction: Helicobacter pylori is a Gram-negative bacillus, responsible for numerous gastroduodenal pathologies and this infection constitutes a public health problem. The prevalence of infection with this bacterium remains high in countries with limited resources

Validation of a rapid SARS-CoV-2 antibody test in general practice

ObjectivesTo validate a rapid serological test (RST) for SARS-CoV-2 antibodies used in seroprevalence studies in healthcare providers, including primary healthcare providers (PHCPs) in Belgium.DesignA phase III validation study of the...

COVID-19 seroprevalence among local authority workers from Orléans Métropole, the Community of Communes of the Terres du Val de Loire, the local public service management centre of the Loiret department and the Region Centre Val de Loire: a prospective epidemiological study

ObjectiveTo evaluate the SARS-CoV-2 seroprevalence among local authority workers, depending on their position and potential interaction with the public.MethodsA cohort of volunteer participants was recruited among local authority workers of...

Seroprevalence Rate and Factors Causing African swine fever Outbreak in Kupang City and Regency of East Nusa Tenggara Province, Indonesia

African Swine Faver (ASF) disease was reported in Indonesia in 2019. ASF outbreaks occurred in East Nusa Tenggara Province in 2020 and 2021, with hundreds of thousands of pig deaths. An effective vaccine to prevent the transmission of ASF is currently undiscovered. The diagnosis of ASF is based on the observation of clinical symptoms, observation of the epidemiology of the disease, and laboratory examinations of both serological, virological, and post- mortem tests. Rapid and accurate serology tests are indispensable to prevent the transmission of ASF infection. A risk- based approach to infectious sources needs to be taken to prevent the emergence of ASF outbreaks. This study aims to determine ASF seroprevalence and identify factors that play a role in the transmission of the ASF virus. The results of the study obtained a seroprevalence rate of 52.9%. Risk factors that act as a source of ASF transmission are the origin of pig livestock from the animal market (6.7%), feed from swill feeding (61.7%), non-routine health checks carried out (90%), pig carcasses thrown into landfills (20%), manure waste left alone (33.3%) and sick pigs immediately sold (60%).

Evaluation of ten (10) SARS-CoV-2 rapid serological tests in comparison with WANTAI SARS-CoV-2 ab ELISA in Burkina Faso, West Africa

BackgroundThe aim of this study was to evaluate the performance of ten (10) SARS-CoV-2 serological rapid diagnostic tests in comparison with the WANTAI SARS-CoV-2 Ab ELISA test in a laboratory setting.Materials and methodsTen (10) SARS-CoV-2 serological rapid diagnostic tests (RDTs) for SARS-CoV-2 IgG/IgM were evaluated with two (2) groups of plasma tested positive for one and negative for the other with the WANTAI SARS-CoV-2 Ab ELISA. The diagnostic performance of the SARS-CoV-2 serological RDTs and their agreement with the reference test were calculated with their 95% confidence intervals.ResultsThe sensitivity of serological RDTs ranged from 27.39 to 61.67% and the specificity from 93.33 to 100% compared to WANTAI SARS-CoV-2 Ab ELISA test. Of all the tests, two tests (STANDARD Q COVID-19 IgM/IgG Combo SD BIOSENSOR and COVID-19 IgG/IgM Rapid Test (Zhejiang Orient Gene Biotech Co., Ltd)) had a sensitivity greater than 50%. In addition, all ten tests had specificity greater than or equal to 93.33% each. The concordance between RDTs and WANTAI SARS-CoV-2 Ab ELISA test ranged from 0.25 to 0.61.ConclusionThe SARS-CoV-2 serological RDTs evaluated show low and variable sensitivities compared to the WANTAI SARS-CoV-2 Ab ELISA test, with however a good specificity. These finding may have implications for the interpretation and comparison of COVID-19 seroprevalence studies depending on the type of test used.