ABSTRACT
In this COVID-19 pandemic, there is a dire need for cost-effective and less time-consuming alternatives for SARS-CoV-2 testing. The RNA extraction-free method for detecting SARS-CoV-2 in saliva is a promising option. This study found that it has high sensitivity (85.34%), specificity (95.04%), and was comparable to the gold standard nasopharyngeal swab (NPS) sample tests. The method showed good agreement between salivary and NPS samples, with a kappa coefficient of 0.797. However, there are variations in the sensitivity and specificity based on the RT-PCR kit used. The Thermo Fisher Applied Biosystems showed high sensitivity, positive predictive value (PPV), and negative predictive value (NPV) but also showed a higher percentage of invalid reports. On the other hand, the BGI kit showed high specificity, better agreement (kappa coefficient) between the results of saliva and NPS samples, and higher correlation between the Ct values of saliva and NPS samples. Thus, the RNA extraction-free method for salivary sample serves as an effective alternative screening method for COVID-19.
Subject(s)
COVID-19 Testing/methods , COVID-19/virology , RNA, Viral/isolation & purification , SARS-CoV-2/isolation & purification , Saliva/virology , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19 Nucleic Acid Testing , Cost-Benefit Analysis , Diagnostic Tests, Routine , Humans , Mass Screening/methods , Nasopharynx/virology , Pandemics , Polymerase Chain Reaction/methods , Predictive Value of Tests , RNA, Viral/genetics , Reagent Kits, Diagnostic , SARS-CoV-2/genetics , Sensitivity and Specificity , Specimen Handling/methodsABSTRACT
Measles is a contagious viral infection that usually affects children. The disease is caused by morbillivirus, a virus of the family Paramyxoviridae. The clinical picture is characterized by four phases: incubation, invasion, eruption and desquamation. Ophthalmologic manifestations in measles are rare, dominated by conjunctivitis and keratitis. Corneal involvement is the main concern; it varies from simple superficial punctate keratitis to corneal perforation. We report three cases of acute keratitis in young adults during an epidemic. The epithelial involvement was peripheral, central or diffuse. The outcome was favorable under symptomatic topical treatment.