Viral Diagnostics in the Clinical Laboratory a Over 70% of all infectious disease cases seen by a physician are due to viral infections a Quality of patient specimens and their transport to the laboratory is important
Viral Diagnostics in the Clinical Laboratory Over 70% of all infectious disease cases seen by a physician are due to viral infections. Quality of patient specimens and their transport to the laboratory is important
Relation of stage of illness to presence of virus in test material &s to appearance of specific antibody Stage or period Virus Specific of illness detectable antibody Incubation R arely No Prodrome Occasionally No Onset Frequently Occasionally Acute pl ase Frequently Frequently Recovery Rare Usually Convalescence ry rarely sually
Relation of stage of illness to presence of virus in test material & to appearance of specific antibody Stage or period of illness Virus detectable Specific antibody Incubation Rarely No Prodrome Occasionally No Onset Frequently Occasionally Acute phase Frequently Frequently Recovery Rarely Usually Convalescence Very rarely Usually
Storage and Collection of Biological Specimens for Viral Testing a What types of specimens are collected to diagnose? O Respiratory tract infections: Nasal and bronchial washings throat and nasal swabs, sputum O Eye infections. throat and conjunctival swab/scraping D Gastrointestinal tract infections: stool and rectal swabs a Vesicular rash: vesicle fluid, skin scrapings a Maculopapular rash: throat stool and rectal swabs O CNS(encephalitis and meningitis cases) stool, tissue, saliva, brain biopsy cerebrospinal fluid D Genital infections vesicle fluid or swab a Urinary tract infections: urine a Bloodborne infections: blood
Storage and Collection of Biological Specimens for Viral Testing What types of specimens are collected to diagnose? Respiratory tract infections: Nasal and bronchial washings, throat and nasal swabs, sputum Eye infections: throat and conjunctival swab/scraping Gastrointestinal tract infections: stool and rectal swabs Vesicular rash: vesicle fluid, skin scrapings Maculopapular rash: throat, stool, and rectal swabs CNS (encephalitis and meningitis cases): stool, tissue, saliva, brain biopsy, cerebrospinal fluid Genital infections: vesicle fluid or swab Urinary tract infections: urine Bloodborne infections: blood
Collection of vesicular fluid from palmar lesions for virological diagnosis of HFMD
Collection of vesicular fluid from palmar lesions for virological diagnosis of HFMD
Three General Approaches for Laboratory Diagnosis of Viral Infections ■ Direct detection a Microscopy or staining a Detection of nucleic acid, antigens Virus Isolation(Indirect Examination) D CPE and other characters nucleic acid antigens for detection ■ Serology □ Antibodies
Three General Approaches for Laboratory Diagnosis of Viral Infections Direct detection Microscopy or staining Detection of nucleic acid, antigens Virus Isolation (Indirect Examination) CPE and other characters nucleic acid, antigens for detection Serology Antibodies