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Alexander McAdam, MD, PhD, and Sara Vargas, MD

Insights on a new virus

Two Children's Hospital Boston teams have filled in some blanks about human metapneumovirus (hMPV), a childhood respiratory virus first discovered in 2001. One team, led by Alexander McAdam, MD, PhD, in Laboratory Medicine, tested respiratory specimens from more than 800 CHB patients. Six percent tested positive for hMPV, making it the second most common virus found, after respiratory syncytial virus. hMPV peaked from January through March and was found most often in children 3 months to 2 years old. Findings appear in the July issue of the Journal of Infectious Diseases.

A serendipitous meeting on the #39 bus between McAdam and pathologist Sara Vargas, MD, led to another study. Vargas, learning of McAdam's work, decided to examine pathology specimens from the hMPV-positive patients. Six such specimens were available, and Vargas will soon publish detailed findings in the Journal of Pediatric and Developmental Pathology. Her group is the first to describe the airway cell and tissue damage caused by hMPV, and their findings will help pathologists make a diagnosis.

 

Immunology seeks to make smallpox immunization safer

Children's Hospital Boston is working to address a potentially life-threatening complication of smallpox immunization, known as eczema vaccinatum (EV). The goal is to reduce the risk of EV, a severe skin infection caused by vaccinia, the live virus used in smallpox vaccine.

Because of recent bioterrorism concerns, the government would like to reintroduce widespread smallpox immunization, but the risk of EV has been a major barrier. For reasons that are unknown, this risk is especially high in people with ordinary eczema. "Since 5 percent of kids and about 1 percent of adults have eczema, the risk is great, should a decision be made to mass vaccinate," says Raif Geha, MD, chief of Immunology at Children's.

Children's will conduct clinical and animal studies to explore why people with eczema are susceptible to EV. Geha will lead animal work at five subcontracting institutions under a five-year, $10 million grant from the National Institute of Allergy and Infectious Diseases. His own lab will develop a mouse model for eczema, examine the immune response to vaccinia virus, seek factors that predispose mice to EV and test preventive strategies. Hans Oettgen, MD, PhD, clinical director of Immunology, will focus on skin abnormalities, comparing immune responses to vaccinia virus, herpes simplex virus and yellow fever virus.

On the clinical side, Lynda Schneider, MD, director of the Allergy Program, has a three-year grant of approximately $450,000. Using varicella—the virus that causes chickenpox—as a "surrogate" for smallpox vaccine, her team will compare the immune responses of children with and without eczema.