Prolonged persistence of measles virus RNA is characteristic of primary infection dynamics

Area of Science:

• Virology
• Immunology
• Infectious Diseases

Background:

• Measles virus (MeV) typically causes acute infection with lifelong immunity.
• Recent findings indicate prolonged MeV RNA presence post-infection in some children.
• The dynamics of viral RNA clearance and the role of host immunity require further investigation.

Purpose of the Study:

• To investigate the characteristics of prolonged MeV RNA presence during primary infection.
• To elucidate the phases of MeV RNA clearance from the blood.
• To model the influence of host immune factors on MeV load dynamics and RNA elimination.

Main Methods:

• Experimental infection of rhesus macaques with MeV.
• Quantification of viral RNA and infectious virus in various tissues.
• Development of a mathematical model incorporating T-cell responses, antibody responses, target cell limitations, and regulatory T cells.

Main Results:

• Prolonged viral RNA presence (4-5 times longer than infectious virus) is characteristic of primary MeV infection.
• MeV RNA clearance from blood occurs in three distinct phases: rapid decline, rebound, and slow decrease.
• Mathematical modeling suggests antibodies are essential for viral RNA elimination, despite initial regulation by T cells.

Conclusions:

• Prolonged viral RNA persistence is a feature of primary measles virus infection.
• Antibody responses play a critical role in the ultimate clearance of MeV RNA.
• These findings necessitate a revised understanding of acute viral infections, immunity development, and viral evolution.