Human metapneumovirus, its epidemic waves, innate immune response and association with extra-pulmonary manifestations

Abstract

Respiratory tract infections are a leading cause of morbidity and mortality worldwide.Although the classical manifestations of respiratory tract infections are defined, thepathological cause responsible for disease is not often identified. Humanmetapneumovirus (hMPV) causes a spectrum of illnesses ranging from asymptomaticinfection to severe bronchiolitis. Little is yet known about the pathophysiology ofhMPV infection, however, it is similar to the related pneumovirus and humanrespiratory syncytial virus (hRSV). Since hMPV appears to cause disease similar tothat of hRSV, one can hypothesize that hMPV also causes similar extra-pulmonarymanifestations. The objectives of this thesis were divided into three main areas;prevalence / diagnosis, immune response, and role of hMPV in extra-pulmonarymanifestations. This study reports, for the first time, the prevalence and clinical pictureof hMPV infection in the Maltese community. Moreover, it suggests that the use ofdetection assays such as real-time PCR would be very helpful in the diagnosis and earlytreatment of viral respiratory pathogens, such as hMPV especially in pediatric andimmunocompromised patients. This study also suggests that multiplex RT-PCR assaysreduce the turnaround time and have higher detection rates than shell vial cultures. Upto now, there have been no confirmed reports of hMPV causing disease outside therespiratory tract. Although a positive hMPV result in a subject with documentedmyocarditis suggests that hMPV was the sole etiological agent, the association of thisvirus with myocarditis was not statistically significant. Nevertheless, to investigate thispotential relationship further large prospective studies are needed.

Date of Award	Sept 2012
Original language	English
Supervisor	ANNE BRIDGEN (Supervisor) & DANIEL QUINN (Supervisor)