Date of Award
Doctor of Philosophy (PhD)
The development of specific antiviral therapy has increased the need for rapid viral diagnosis and necessitates a better understanding of viral epidemiology. The purposes of this study were to determine the efficiency of immunofluorescent assay employing monoclonal antibodies from commercial sources to detect respiratory virus antigens in clinical specimens and to define the epidemiology of respiratory viruses in Bismarck, North Dakota.
Throat swab, nasopharyngeal swabs and nasopharyngeal washes were excellent specimens for studying viral epidemiology; virus isolation rates were 7.7%, 33.2%, and 39.7%, respectively. Yearly epidemics of respiratory syncytial virus and influenza were observed. In contrast, parainfluenza and adenovirus infections occurred endemically throughout the study period. Children less than 6 years of age and adults greater than 50 years of age had the highest viral morbidity. Respiratory syncytial and influenza were the most frequently isolated viruses.
Nasopharyngeal swab and nasopharyngeal wash specimens were evaluated for the ability to harvest ciliated epithelial cells from the upper respiratory tract. Overall, 8.7% of the specimens were unsuitable for immunofluorescent assay. The probability of specimen rejection was source- and patient age-dependent. The rejection rate for NPW specimens was more than twice that for NPS specimens and the rejection rate for specimens from patients greater than 7 years of age was approximately 5 times higher than the rate for specimens obtained from patients less than 6 years of age.
Immunofluorescent assay was a sensitive and specific method for rapid diagnosis of respiratory viral infections in cell cultures. The Bartels indirect fluorescent antibody reagents exhibited acceptable levels of sensitivity (overall 84.6%, range 33.3-100%) and specificity (overall 83.3%, range 87.3-100%). The Whittaker direct fluorescent antibody reagents had poor sensitivity (overall 50%, range 18.2-94.1%) and high specificity (overall 91.5%, range 93.8-100%). The highly efficient Bartels reagents for respiratory syncytical virus and influenza A virus could be used as acceptable alternatives to culture for these viruses. The specificity of the influenza B, parainfluenza 3 and adenovirus reagents allowed for rapid presumptive diagnosis but were not sufficiently sensitive to replace culture.
Shell vial assays using HEp-2 and A549 cells offered no diagnostic advantage over immunofluorescent assay or conventional tube cell culture for the identification of respiratory viruses.
Immunofluorescent assay using commercial monoclonal antibodies was a sensitive and specific method for rapid diagnosis of respiratory virus infections and has the potential to replace expensive and laborious conventional culture methods.
Irmen, Kenneth E., "Efficiency of Monoclonal Antibodies to Detect Respiratory Virus Antigens in Clinical Specimens" (1990). Theses and Dissertations. 813.