Polymerase Chain Reaction Test Research Articles

Predicting COVID-19 Mortality and Identifying Clinical Symptom Patterns in Hospitalized Patients: A Machine-learning Study

Background and Purpose: Identifying effective symptoms, demographic information, and underlying diseases to predict COVID-19 mortality is essential. We aimed to study the effective clinical and symptomatic characteristics of COVID-19 mortality in hospitalized patients with positive polymerase chain reaction (PCR) test results. Materials and Methods: For this study, we prospectively collected complete data on 26867 hospitalized individuals who tested PCR positive for COVID-19 from February 20, 2020, to September 12, 2021, in the Khorasan Razavi Province, Iran. We analyzed the data using artificial neural networks (ANN) and logistic regression (LR) models. Results: The accuracy of the ANN model was higher than the LR (90.27% versus 90.15%). The ten most important predictors that contributed to the prediction of death were decreasing consciousness level, cough, PO2 level, age, chronic kidney disease, fever, headache, smoking status, chronic blood diseases, and diarrhea using the ANN model. Conclusion: In conclusion, individuals suffering from chronic diseases such as cancer, kidney and blood diseases, as well as immunodeficiency are at a higher risk of mortality. This important finding can help decision-makers and medical professionals in their efforts to consider these conditions and provide effective preventative measures to reduce the risk of death.

Comparison of Xpert Xpress SARS-CoV-2 Assay Compared with Standard M nCoV Real-Time PCR: Prospective Study.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can be diagnosed using rapid real-time polymerase chain reaction (PCR), real-time reverse transcription PCR (rRT-PCR), or rapid antigen testing. Among these, rRT-PCR is considered the gold standard assay. The Xpert Xpress SARS-CoV-2 assay is a rapid, real-time PCR test; approved by the Korean Disease Control and Prevention Agency in 2020. Current performance of the Xpert assay (Xpert) with the STANDARD M nCoV Real-Time Detection kit (SD) were determined. All samples used by the SD test team were immediately transferred to the Xpert test team within 24 hours. Both tests were conducted between April 2023 and July 2023. Exclusion criteria were studies which show either inconclusive, invalid, or erroneous results. Positive rate, sensitivity, specificity, overall concordance rate, positive concordance rate, discordance rate, false-positive rate, and false-negative rates of the Xpert assay with the STANDARD M nCoV Real-Time Detection kit were determined. Samples from 347 patients (174 men and 173 women) with a median age of 60 years (range; 6 - 90 years) were included. Positive rate, sensitivity, specificity, overall concordance rate, positive concordance rate, discordance rate, false-positive rate, and false-negative rates of the Xpert assay were 11.2%, 82.1%, 95.0%, 93.9%, 6.6%, 6.1%, 41.0%, and 1.6%, respectively. COVID-19 results from Xpert should be confirmed through rRT-PCR because of low sensitivity (82.1%) and high false-positive rate (41.0%).

Seroconversion, genotyping, and potential mosquito vector identification of Japanese encephalitis virus in pig sentinel settings in Bali, Indonesia.

Despite the endemicity of Japanese encephalitis virus (JEV) in humans and animals in the Province of Bali, Indonesia, there is little data on whether seroconversion to the virus occurs in pigs, JEV genotypes circulating, and it's potential mosquito vectors in the area. The aims of this study were to (i) Determine whether JEV infection in Balinese pigs occurs before reaching their sexual maturity, (ii) identify the genotypes of circulating JEV, and (iii) identify potential JEV mosquito vectors at the study sites in urban and peri-urban areas of Bali. Sixteen 1-week-old Landrace piglets from two different sows were housed in Denpasar. Similarly, 18 one-week-old mixed-breed piglets of two different sows were housed in Badung Regency. The piglets were bled every 1 to 4 weeks for up to 24 weeks. Serum samples from the 11 piglets were tested for antibodies against JEV, and seroconversion-suspected sera were titrated using an enzyme-linked immunosorbent assay. Blood of seroconverted sera from pigs were tested using polymerase chain reaction (PCR) to detect the genetic sequence of JEV. The mosquitoes in the sentinels were trapped throughout the study period to identify the potential mosquito vectors of JEV. Antibodies were detected in most of the selected piglets' sera from weeks 1 to 24 of their age. However, sera of pig B9 collected from the sentinel setting in Badung Regency showed a four-fold increase in antibody titer from week 4 to week 8, indicating seroconversion. PCR testing of blood from B9 (pooled blood sample collected from week 5 to week 8) identified JEV nucleic acids, which were phylogenetically classified as belonging to the JEV genotype III. Meanwhile, 1271 of two genera of mosquitoes, Anopheles spp. and Culex spp. were trapped in the pig sentinels. JEV seroconversion likely occurs before the pig reaches sexual maturity in Badung Regency. Sequence data indicate that JEV genotype III is circulating in the pig sentinel setting in the regency; however, circulating genotypes need to be clarified through increased surveillance. Meanwhile, Culex spp. and most likely Culex quinquefasciatus and Anopheles spp. were the dominant mosquitoes present in the study sites set in the urban area of Denpasar and peri-urban areas of Badung, Bali, indicating that these are likely vectors in spread of JEV in the region.

Visual evoked potential abnormalities in patients with COVID-19.

It has been suggested that diseases that may cause visual evoked potential abnormality, such as optic neuritis, may be associated with the coronavirus disease 2019. This study aimed to find out whether there are visual evoked potential abnormalities in coronavirus disease 2019 patients using pattern reversal visual evoked potential and flash visual evoked potential. Patients with a history of coronavirus disease 2019 (coronavirus disease 2019 patients) and controls were included in this prospective case-control study. This study was conducted in the Clinical Neurophysiology Laboratory of Adana City Training and Research Hospital. Individuals without visual impairment were included. Coronavirus disease 2019 patients were required to have clinical features consistent with previous acute infection and a positive nose swab polymerase chain reaction test. Visual evoked potential was applied to coronavirus disease 2019 patients between July 2020 and July 2021. Controls consisted of patients without a history of chronic disease who underwent a visual evoked potential study between June 2017 and June 2018 due to headache or dizziness. Pattern reversal visual evoked potential and flash visual evoked potential were applied to all participants. N75, P100, and N135 waves obtained from pattern reversal visual evoked potential and P1, N1, P2, N2, P3, and N3 waves obtained from flash visual evoked potential were analyzed. A total of 44 coronavirus disease 2019 patients and 40 controls were included in the study. Age and gender were not different between the two groups. Pattern reversal visual evoked potential parameters were not different between the two groups. Right P2 latency was 114.4±21.1 and 105.5±14.7 ms in coronavirus disease 2019 patients and controls, respectively (p=0.031). Patients with P100 and P2 wave abnormalities were 6 (13.6%) and 13 (29.6%), respectively. This study showed that there may be visual evoked potential abnormalities in coronavirus disease 2019 patients.

A Different Perspective of COVID-19 Pandemic: Efficacy and Safety of mRNA Vaccines in Immunocompetent and Immunocompromised Individuals (Part 3).

Shortly after the declaration of the pandemic, several anti-SARS-CoV-2 vaccines entered phase 3 clinical trials. One year later, Pfizer-BioNTech and Moderna published their initial trial results, encompassing a 2-month follow-up. The studies were only designed to test whether the vaccines were effective and safe on the short-term.The vaccine's efficacy in the 2 trials was defined as relative risk reduction instead of absolute risk reduction, a more accurate determinant of vaccine effectiveness in the real world. These studies were not designed to assess viraltransmission, disease severity, and death as primary outcomes.Vulnerable subgroups of individuals were excluded from the studies. No correlate of immunity against the SARS-CoV2 was identified.Vaccine-induced immunity declined shortly after vaccination and was not protective against new variants. Vaccination and boosting effectiveness were suboptimal in immunocompromised patients. In contrast, in recovered COVID-19 patients, natural immunity was shown to be protective, lasting longer and being more effective against new variants. Findings from subsequent scientific reports questioned the effectiveness of these vaccines in providing protective immunity despite boosting in infection-naïve and infection-experienced individuals. Reports also raised concerns on their safety in relation to cardiovascular pathology, sudden death, and acquired autoimmunity mainly in the low-risk young population. With the doubtful accuracy of the polymerase chain reaction testing in relation to case definition and diagnosis, the inability of the vaccines to stop viral transmission, the uncertain effectiveness of these vaccines, and serious adverse events of these vaccines lead us to question the validity ofthe vaccine mandate in public and private domains.

Intrahepatic Cholestasis of Pregnancy and Transaminitis in Women with COVID-19: A Case Series.

Objective The four initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected pregnant women presenting at term gestation to our institution presented with transaminitis. Three of the four were diagnosed with intrahepatic cholestasis of pregnancy (IHCP). Growing evidence exists of an associated transaminitis in nonpregnant SARS-CoV-2 patients. However, there are limited data of hepatic involvement of SARS-CoV-2 in pregnancy, and no previous studies have assessed the association with IHCP in patients with coronavirus disease 2019 (COVID-19). Study Design This was a retrospective, single-center case series of four consecutive pregnant women with a positive result for SARS-CoV-2 presenting with transaminitis in third trimester. Results The clinical courses of four pregnant women with COVID-19 and transaminitis, three of four of whom were diagnosed with IHCP, are described. Testing for SARS-CoV-2 was done through a reverse transcription polymerase chain reaction test of a nasopharyngeal swab. Conclusion As we await larger studies ascertaining the incidence of IHCP in SARS-CoV-2, this prevalence highlights the importance of diagnosing IHCP among women with COVID-19 as a potential etiology of transaminitis, as IHCP risks may be ameliorated with earlier delivery. Moreover, delineating a hepatobiliary association in pregnancy may provide further information about the mechanism of liver impairment in SARS-CoV-2 in all patients.

Sequencing of pigeon circovirus and the first report of identification of beak and feather disease virus in clinical specimens of domestic pigeons.

An internationally recognized syndrome that leads to deaths among domestic and ornamental pigeons, particularly after racing, is young pigeon disease syndrome (YPDS). Pigeon circovirus (PiCV) is regarded as one of the potential factors contributing to the occurrence of YPDS. This survey was conducted to determine the prevalence of PiCV infection and molecularly characterize the PiCV in pigeons suspected of YPDS. Eighty fecal samples were collected from 80 diseased pigeons (exhibiting symptoms such as lethargy, weight loss, crop stasis, vomiting and diarrhea) from 20 lofts in different areas of Ahvaz, Iran. Also, 20 fecal samples were obtained from 20 clinically healthy pigeons. The nested broad spectrum polymerase chain reaction test was done to identify the circovirus, using primers targeting part of the replication-associated protein gene with 350 bp, and several positive samples were sequenced. This study showed that PiCV was detected in 86 out of the 100 samples (86.00%). Two types of circoviruses were determined in the samples. One type of the detected circoviruses was PiCV which based on phylogenetic analysis had high genetic similarity with A, B, G and H genotypes of PiCV. The other type of detected circoviruses was closely related to beak and feather disease virus (BFDV) which causes one of the most significant viral diseases in psittacine birds. This is the first report of BFDV identification in pigeons.

Laboratory Diagnosis of Genital Tuberculosis: A Narrative Review

Genital tuberculosis is a leading cause of infertility in high tuberculosis burden countries like Bangladesh. Diagnosing this condition can be challenging due to the diverse ways it can present, which requires a physician to have a high level of suspicion. The fallopian tubes are mainly affected, and the endometrium in 50% of cases1. Diagnostic modalities usually include histopathology, microscopy, solid and liquid culture tests, Polymerase Chain Reaction (PCR) tests, immunohistochemistry tests, radiology imaging and laparoscopic and hysteroscopic procedures.
 Bangladesh Journal of Infectious Diseases, December 2023;10(2):92-100

Comparative studies on the detection of Theileria annulata infection by clinical, parasitological and molecular techniques in buffaloes (Bubalus bubalis)

During the period of 2019-2021, a total of 715 buffaloes were screened for Theileria infections. A set of clinical parameters were used to identify the theileriosis suspected animals which were later confirmed through microscopic tests (peripheral thin blood smear examination and lymph node biopsy smear examination) and molecular assay (cytochrome b based T. annulata specific polymerase chain reaction test). On the basis of clinical evaluation, 33.43% (239/715) buffaloes were suspected for the presence of theileriosis. Through laboratory examination, 63.60% (152/239), 7.48% (16/214) and 100% (239/239) were found positive for Theileria infection by blood smear examination, lymph node biopsy and PCR, respectively, among the clinically suspected theileriosis animals. The efficiency of PCR was recorded to be highest, followed by microscopic examination of peripheral blood smears, and the lowest value was obtained for lymph node biopsy smear examination. The results indicated that PCR is a highly sensitive diagnostic technique for confirmatory diagnosis of T. annulata parasitic infection in buffaloes, even at very low level of parasitemia. Analysis of the data based on thin blood smear examination revealed that the field incidence of theileriosis was 11.55% in the south-western region of Gujarat, India. The high incidences of T. annulata infection in buffaloes may be due to the sub-tropical climate of the region which is favorable for the growth and development of vector ticks and parasites.

ISOLATION, MOLECULAR IDENTIFICATION AND ANTIBIOTIC SENSITIVITY OF SALMONELLA FROM BUFFALO FECES IN SYLHET DISTRICT OF BANGLADESH

Salmonella is a widely distributed foodborne pathogen affecting humans and animals around the globe. This cross-sectional bacteriological study was aimed at isolation of Salmonella from fecal samples of buffalos in Sylhet district (Upazilas Jaintapur and Fenchuganj) of Bangladesh, their molecular confirmation, and learning their antibiotic sensitivity patterns. A total of 334 fecal samples were collected using a simple random sampling technique. Standard conventional bacteriological culture and biochemical tests were done to isolate and confirm Salmonella. The isolates were confirmed with polymerase chain reaction (PCR). In this study, Salmonella was isolated from 56 samples (16.77%) using bacteriological culture methods and biochemical tests, and all isolates were confirmed in PCR tests. The prevalence of Salmonella was estimated to be 17.57% and 13.93% in Jaintapur and Fenchuganj Upazilas, respectively. Buffalo calves under one year of age had a higher prevalence (24.32%) than older animals aged 1 - 2 (18.62%), 2 - 4 (13.25%), and > 4 years (10.67%). Furthermore, the prevalence was substantially higher in diarrheic animals (72.22%) than in their healthy counterparts (13.60%). It did not vary significantly (p > 0.05) between animals from Jaintapur and Fenchuganj Upazilas. Likewise, no significant difference (p > 0.05) in Salmonella isolates was detected between different age groups. The results revealed that the isolation rate of Salmonella was significantly (p < 0.05) higher in female and diarrheic animals. The most effective antibiotics against the majority of Salmonella isolates were gentamycin (100%), levofloxacin (100%), and ciprofloxacin (76.67%). On the other hand, Salmonella isolates were highly resistant to tetracycline (100%), ampicillin (87.5%), and streptomycin (78.6%). Pathogenic microorganisms in feces are a potential risk to public health due to environmental and animal food contamination. Therefore, infection control and establishing strategic antibiotic therapy should be a priority.

Impact of Vaccines on Mortality in Patients Treated in The Intensive Care Unit Due To COVID-19: A Multicenter Study

Introduction: The importance of vaccines is increasing day by day because the COVID-19 pandemic has been going on for about two years and there is no effective antiviral treatment. The purpose of this study was to compare the impact of vaccination status on the mortality of patients monitored in the intensive care unit with the diagnosis of COVID-19.
 Methods: Three hundred and forty-four patients treated in intensive care due to COVID-19 in three hospitals in Gaziantep were included in the study. Demographic characteristics and pre-COVID-19 vaccination status of all patients were recorded, and the diagnosis of COVID-19 was made with nasopharyngeal polymerase chain reaction (PCR) test and Thorax Computed Tomography (CT).
 Results: Of the patients, 172 (50%) were male, 172 (50%) were female, 152 (44%) were unvaccinated and 192 (55%) were vaccinated. The number of male patients (n=106) (55.2%) in the vaccinated group was significantly higher than female patients (n=86) (44.8%) (p

ISOLATION, IDENTEFECATION AND EFFECINCY OF PSEUDOMONAS FLUORESCENS BACTERIA TO TERMITE MICROCEROTERMIS DIVERSUS

This study was conducted to isolate the bacteria Pseudomonase fluorescens from the termite, locust, and American cockroach in the Iraqi environment and to diagnose it based on morphological, biochemical, and molecular diagnosis using the polymerase chain reaction (PCR), as well as test its pathogenicity and efficacy to termites under laboratory conditions. The results of morphological , biochemical, and molecular diagnosis using polymerase chain reaction (PCR) tests showed the isolated bacterial isolates are similar to P. fluorescens .The results of efficiency of different isolates of P. fluorescens showed that they have a high pathogenicity towards termite workers in laboratory and incubation condition.

Association between Rotavirus Infection and Irritable Bowel Syndrome: A Case-Control Study in Kerman, Iran

Background: Irritable bowel syndrome (IBS) is a functional gastrointestinal disease of unknown etiology. Researchers have recently drawn attention to the possible role of viruses in the development of IBS and provided evidence in this regard. In this study, it was decided to investigate the possible role of rotavirus infection in the onset of IBS. Methods: Stool and serum samples were collected from 40 patients with IBS and 40 healthy individuals. To evaluate the previous exposure to rotavirus we checked the presence and concentration of anti-rotavirus IgG by ELISA. ELISA test was performed on the serum samples. A real-time polymerase chain reaction (PCR) test was also used to measure the viral load in the stool. Finally, the data were analyzed by SPSS version 22 software. Results: No significant relationship was found between anti-rotavirus IgG presence and its level in the serum of case and healthy individuals (P value>0.05). Moreover, there was no significant difference between the viral genome load in the stool samples of the two groups (P value>0.05). Conclusion: According to the results, it seems unlikely that a link exists between rotavirus infection and the onset of IBS, but the possible role of other gastrointestinal viruses, including coronavirus, remains.

Impact of Post-mortem PCR Testing on Lead Time of the Medico-legal Death Investigation. A Retrospective Study During the COVID-19 Pandemic in a Tertiary Care Hospital in Sri Lanka

Introduction: The lead time is defined as the time between the beginning of a process or project and the appearance of its results. A post-mortem nasopharyngeal swab is the preferred specimen and Real-time reverse transcriptase-polymerase chain reaction-based assays remain the “gold standard” for the detection of severe acute respiratory syndrome coronavirus 2. Although the RT-PCR provides a relatively rapid result (average 6 hours) the process of post-mortem specimen collection, transportation, and real-time polymerase chain reaction testing lead to the increased time duration of releasing the deceased to the next of kin. This study aims to assess the effectiveness of the institutional policies governing autopsies adopted during the COVID-19 pandemic at the medico-legal unit of Matale in decreasing the lead time of medico-legal death notification.Methods: This study was conducted at the medico-legal unit of District General Hospital Matale, Sri Lanka. All data was collected from the post-mortem reports and records maintained at MLU of Matale from May 2021 to December 2021. All the post-mortems conducted by the author (442 autopsies) were included.Results: The study population comprised of 283 (64%) males. The majority (30%, n=134) of the decedents were more than 80 years. The mean age of the deceased was 69.20 years and the standard deviation was 17.881. The majority (66%, n=291) of the descendants were Sinhala. The majority of inquests (n= 423, 96%) were conducted by inquire into deaths. In the months of August and October number of autopsies performed had increased 4 times and 3 times respectively to that of the same period in previous years and the following year. Out of the autopsies, 23% (n= 101) of the lead time of autopsy was on the same day of death. In the majority (64 %, 85) of the deaths lead time of autopsy was the next day of the death.Conclusion: During the COVID-19 pandemic, excess mortality was detected, lead time of autopsy was reduced due to the policies adopted by the medico-legal unit. Lessons learned during the pandemic may help improve resource utilization without negatively influencing outcomes in a low-resource setting.

COVID-19 vaccination coverage among travellers at Lomé international airport (Togo), in 2022.

COVID-19 pandemic management leads to new health policies including the requirement of a vaccination pass or a negative Polymerase Chain Reaction (PCR) test for cross-border flights. The objective of this study was to estimate COVID-19 vaccination coverage among travellers, as well as factors associated with a full vaccination. A cross sectional study was conducted in July 2022 at the Gnassingbé Eyadema International Airport (LFW) in Lomé. Travellers met at LFW, aged 12 years or above, and who agreed to participate in the study have been submitted a questionnaire. Logistic regression analysis was performed to identify factors associated with full vaccination defined as having received at least two doses of COVID-19 vaccine according to a validated vaccine schedule. A total of 847 travellers were included. 67% were men The median age was 40 years, Interquartile Range [31-48]. The main health document presented by travellers was the vaccination pass (69.1%). The majority (84.4%) of travellers had received at least one dose of COVID-19 vaccine and 63.9% had received at least two doses. Being 40 years of age or above (aOR=1.42; P=0.046), and travelling from a country outside Africa (aOR=2.18, P=0.003), were positively associated with full vaccination. Vaccination coverage among travellers at the LFW was relatively high. Travellers from a region outside Africa and aged 40 years or above were more likely to be full vaccinated. Better communication and strengthening of the vaccination strategies in Africa could help reduce these gaps.

The effect of video informing adolescents having Polymerase Chain Reaction (rRT-PCR) test on anxiety during the Coronavirüs (COVID-19) pandemic: A randomized controlled study

AimThis study aimed to determine if video information on Polymerase Chain Reaction (rRT-PCR) testing reduces anxiety in adolescents. Design and methodsA randomized controlled experimental study with a parallel-group design was conducted. The sample size was determined by G*Power analysis, and 136 adolescents were included in each group accordingly. The data were collected using the Child/Parent Information Form, State and Trait Anxiety Inventory, and Coronavirus Anxiety Scale. Chi-square, Independent Sample t-test, and Paired Sample t-test were used to analyze the data. ResultsIt was determined that adolescents experienced moderate anxiety before the procedure. It was found that the majority of adolescents did not have a COVID-19 positive patient in their relatives (83.1%) or in the same house (82.7%). It was determined that they had COVID-19 positive friends at school (56.2%) but not in class (61.4%) and had no contact with positive friends (69.1%). While the post-operative state anxiety level of the adolescents informed by video was 38.76 ± 10.77, the anxiety level of the adolescents in the control group was 41.68 ± 11.92. Informing with video significantly decreased the anxiety level of adolescents (p = 0.035). ConclusionVideo information reduces state anxiety after the procedure. Practice implicationsIt is recommended that video information before rRT-PCR test should be implemented in all hospitals, tablets, televisions, or phones should be used to provide information against the risk of contamination, and other studies should be conducted to show the effectiveness of video information.

Clinical characters of COVID-19 patient in a Saudi intensive care unit: A single-center experience

Objectives Address and assess the clinical characteristics and outcomes of COVID-19 patients admitted to the intensive care unit (ICU) of King Saud Hospital Unaizah/Qassim, Saudi Arabia. Material and Methods A single-center observational retrospective study in King Saud Hospital, including 82 critically ill COVID-19 patients admitted to the ICU, confirmed by positive polymerase chain reaction testing of nasopharyngeal specimens. Results The study was conducted on 82 COVID-19 patients from April to October 2020. The mean patient age was 58.48 years. Males were more affected by the virus, accounting for 74% of admissions. Hypertension was our patients’ most common chronic disease (45%). Most (82.9%) of the patients presented with a cough. Leukocytosis, high ferritin, lactate dehydrogenase (LDH), and D-Dimer were associated with an increased risk for mortality. Tocilizumab was associated with good outcomes among our patients. Conclusion In this retrospective study, hypertension and being male are more common factors for disease severity. Patients improved with early intervention with tocilizumab and antibiotics, and in most cases, non-invasive ventilation was associated with good outcomes.

Diagnosis of Tuberculosis by Conventional and Molecular Methods in Our Laboratory: A 4-Year Assessment

Objective: The aim of this study was to compare direct microscopy, culture and Polymerase Chain Reaction (PCR) methods and to present the antibiotic resistance profile of the last 4 years comparatively by conventional and molecular methods.
 Materials and Methods: Bacterial culture, EZN and PCR methods were applied to all samples. Direct rapid resistance test was performed for EZN positive samples. 
 Results: 968 patients were included in the study. Culture was positive in 81 (8%), PCR in 78 (8%) and EZN in 39 (46%) patients. PCR performed on the same day in both respiratory and other samples showed very good agreement with culture, while EZN staining showed moderate agreement. It was observed that the rapid resistance test detected rifampicin resistance which was not detected in culture, and in the case of INH, culture antibiogram and rapid resistance test were fully compatible. Application of the rapid resistance test to every patient with positive EZN staining resulted in very early detection of resistance. 
 Conclusion: It was concluded that PCR tests are useful in the rapid diagnosis of tuberculosis and resistance in suspicious clinical samples.

Clinical and Molecular Detections of Lumpy Skin Disease: Possibilities of Co-infection with Foot-and-Mouth Disease

Lumpy skin disease (LSD) and foot and mouth disease (FMD) are notable viral diseases of cattle. This report aimed to highlight the possibilities of an uncommon case of LSD and FMD co-infection. The report also presents the clinical and molecular detection of LSD virus in six crossbred calves and LSD and FMD virus co-infection in a heifer at small-scale dairy farms located in northern Ethiopia. Nasal swabs and tissue samples were collected following aseptic techniques from the six calves suspected of having LSD and a tissue sample from one heifer suspected of having LSD-FMD co-infection and submitted to the laboratory for cell culture and real-time polymerase chain reaction (PCR) tests. Different-sized, firm, painful skin nodules with necrotic centers were seen on different parts of the calves’ body. Swelling of the prescapular and prefemoral lymph nodes, conjunctivitis, and corneal cloudiness were also observed. Uniquely, one heifer was seen with erosive lesions in the oral cavity and tongue, salivation, lameness, and skin nodules. Intracytoplasmic inclusion bodies, a distinctive feature of LSD virus, and the formation of syncytia, a characteristic of FMD virus, were observed in the cell lines. The heifer was diagnosed with a rare co-infection of LSDV and FMDV based on clinical signs, cell culture, and real-time PCR test results. The other six calves were diagnosed with the LSD virus. Treatment with broad-spectrum antibiotics, local wound cleansing, and anti-inflammatory drugs was initiated. Unfortunately, the heifer with LSD-FMD co-infection died while under treatment, and just three calves with LSD were recovered. It can be concluded that vaccination of animals against both diseases and promotion of bio-security protocols in farms is more helpful than treatment, and early case reporting is also warranted to avoid losses related to the diseases.

A Portable and Disposable Electrochemical Sensor Utilizing Laser-Scribed Graphene for Rapid SARS-CoV-2 Detection.

The COVID-19 pandemic caused by the virus SARS-CoV-2 was the greatest global threat to human health in the last three years. The most widely used methodologies for the diagnosis of COVID-19 are quantitative reverse transcription polymerase chain reaction (RT-qPCR) and rapid antigen tests (RATs). PCR is time-consuming and requires specialized instrumentation operated by skilled personnel. In contrast, RATs can be used in-home or at point-of-care but are less sensitive, leading to a higher rate of false negative results. In this work, we describe the development of a disposable, electrochemical, and laser-scribed graphene-based biosensor strips for COVID-19 detection that exploits a split-ester bond ligase system (termed 'EsterLigase') for immobilization of a virus-specific nanobody to maintain the out-of-plane orientation of the probe to ensure the efficacy of the probe-target recognition process. An anti-spike VHH E nanobody, genetically fused with the EsterLigase domain, was used as the specific probe for the spike receptor-binding domain (SP-RBD) protein as the target. The recognition between the two was measured by the change in the charge transfer resistance determined by fitting the electrochemical impedance spectroscopy (EIS) spectra. The developed LSG-based biosensor achieved a linear detection range for the SP-RBD from 150 pM to 15 nM with a sensitivity of 0.0866 [log(M)]-1 and a limit of detection (LOD) of 7.68 pM.