human cytomegalovirus

Scientists have taken an important step toward understanding a virus that infects and lies dormant in most people, but emerges as a serious illness in transplant patients, some newborns and other people with weakened immune systems. The virus, called human cytomegalovirus, enters the bone marrow and can hide there for a lifetime. Until now, however, scientists had not been able to study the virus in its latent stage because it infects only humans and does not readily infect or become dormant in laboratory strains of bone marrow cells. In a new study researchers demonstrated a laboratory system for studying the virus in its latent stage and discovered a set of genes that may give the virus its great capacity for stealth.