Aim:The present work aimed to develop lateral flow immunochromatographic strip (ICS) test for detection of Salmonella Enteritidis (SE) specific antibodies in chicken sera.Materials and Methods:A rapid lateral flow immunochromatographic test (LFIT) has been developed, in which SE Group D antigen labeled with the gold chloride molecules laid on the conjugate pad. Staphylococcus aureus protein A was used as capture antibody at the test line (T) of a nitrocellulose (NC) membrane and anti-SE antigen-specific rabbit antibodies were used as capture antibody at the control line (C) of the NC strip in the lateral flow layout device.Results:Using the developed LFIT, the minimal amount of SE-specific antibodies that can be detected in chicken serum sample was 1427 enzyme-linked immunosorbent assay (ELISA) unit/100 µl that was equal to 0.1 µg (Ab)/100 µl sample. 100 suspected serum samples collected from a poultry flock were tested with the prepared SE-LFIT kits and the locally prepared stained Salmonella antigen, and the results were compared with those obtained from examination of these samples with Salmonella Group D antibody ELISA kit as the gold standard test. The sensitivity, specificity, and accuracy of the prepared SE-LFIT antigen kits were 94.4%, 90%, and 94%, respectively, while those obtained with stained Salmonella antigen were 88.8%, 90%, and 89%, respectively.Conclusion:The developed test is a simple field rapid test of high sensitivity, specificity, and accuracy that can improve and facilitates rapid field surveillance of salmonellosis among chickens.

In the presented study, we developed a nanogold lateral glow immunoassay-based technique (LFI-COVID-19 antigen test) for the detection of SARS-CoV-2 nucleocapsid proteins; the developed LFI-COVID-19 Ag test has been tested for limit of detection (LOD), cross-reactivity and interfering substances, and performance. It was found that the performance of the developed LFI-COVID-19 antigen test when it was evaluated by RT-qPCR indicated 95, 98, and 97% for sensitivity, specificity and accuracy, respectively. This complies with the WHO guidelines. It was concluded that the developed LFI-COVID-19 antigen test is a point of care and an alternative approach to current laboratory methods, especially RT-qPCR. It provides an easy, rapid (within 20 min), and on-site diagnostic tool for COVID-19 infection, and it is a cheap test if it is manufactured on a large scale for commercial use.

Avian mycoplasmas were mainly the cause of poultry industry economic losses; reduced meat and egg production and increases the antibiotic treatment cost. Mycoplasma gallisepticum (MG) infection is designated as infectious sinusitis of turkeys and chronic respiratory disease of chickens (gasping, depression, semi closed eyes, infraorbital sinuses edema and decrease in egg production). This study aimed to prepare, evaluate and Compare in-house ELISA kits and lateral flow assay (LFA) from a local strain of MG with commercial ELISA kits and PCR consequently. A total of 54 samples (27 tracheal swabs, 10 trachea and 17 lung) and 50 serum samples collected from birds suffering from chronic respiratory disease were tested by prepared in-house ELISA, commercial ELISA kits, PCR and LFA; a high correlation coefficient between in-house ELISA using whole antigen or sonicated antigen and commercial kit was recorded. Lateral Flow assay (LFA) performance indicate a low sensitivity (77.5%) but maintain a high specificity (92%) compared to PCR. The in-house ELISA kits and LFA prepared could be used as a fast diagnostic technique for detection of MG in Egypt. According to the available knowledge the prepared LFA for diagnosis of MG infection in chickens was developed for the first time in Egypt.

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Corynebacterium pseudotuberculosis is responsible for Caseous Lymphadenitis (CLA) disease in small ruminants (goats and sheep). The disease is difficult to control because antibiotic therapy is not effective. The disease is characterized by caseous abscess formation in the internal and external lymph nodes. Diagnosis is currently achieved only by routine bacteriological culture of pus obtained from external abscess. The lateral flow immunochromatographic test (LFIT) was prepared and evaluated for discover the present of Corynebacterium pseudotuberculosis in pus samples obtained from abscess in superficial lymph nodes. The minimal count of bacterial that gave positive LFIT was 10 2 CFU/ 0.1ml. About 100 pus samples from external lymph nodes were examined by the LFIT and the results were compared with conventional microbiological method. The obtained results demonstrate that the specificity was calculated and found to be 88.24%, while sensitivity was 90.36% and finally the accuracy was 90% of LFIT as compared to conventional microbiological method. These findings indicate that the developed LFIT test is a fast, simple and inexpensive field test of good specificity, sensitivity and accuracy that can be used to enhance Caseous Lymphadenitis control among sheep and goats.

Background: Helicobacter pylori (H. pylori) is a Gram-negative bacterium with a wide range of virulence factors that helps surviving the bacterium in gastric environment. World Health Organization labeled H.pylori as class I carcinogen. H. pylori secretes the virulence factor like vacuolating cytotoxin A (vacA) which enhances the pathogenicity of this bacterium. VacA involves in different functions like apoptosis, immune modulation and damaging cellular pathways.Methods and materials: The distribution of H. pylori vacA gene allele of s1a, s1b and s2 in patients suffering from dyspepsia and gastroduodenal mucosal abnormalities were determined in this study, around two hundred and forty samples of biposies were collected from patients through endoscopy for molecular examination. Samples were homogenized and DNA was extracted for polymerase chain reaction (PCR) using specific primers, results were analysed using agarose gel electrophoresis.Results: In collected samples the vacA alleles were distributed as s1a in 144(60%), s1b in 19(8%) and s2 in 77(32%), respectively. VacA gene alleles s1a, s1b and s2 were found to be associate with symptoms like abdominal pain, hematemesis, malena and weight loss in patients. The abdominal pain as the most prominent symptom in patients containing s1a and s2 alelles around 102 and 50 respectively As diagnosed through gastroscopy s1a is mainly associated with 74(31%) patients with nun-ulcer dyspepsia (NUD) and 31(13%) gastric carcinoma (GC), for s2 55(23%) patients were diagnosed with NUD, 12(5%) with GU and 10(4%) with GC.Conclusion: H.pylori prevalence is noticeably higher in developing countries as contrast to developed countries. It has been observed that patients with NUD (nonulcer dyspepsia) were positive for s1a allele of vacA gene in most patients. In Pakistan the prevalence of this bacterium is shockingly high due to factors like socioeconomic or unhygienic food and contaminated drinking water consumption.

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