Stories about: Division of Infectious Diseases

Science Seen: Tackling S. aureus by eavesdropping on infections

S. aureus vaccine messenger RNA transcriptome
This messenger RNA ‘heat map,’ generated from 50 patient samples, shows potential target proteins for a more effective S. aureus vaccine. The color scale indicates the magnitude of the transcription level, with red highest.

Staphylococcus aureus causes 11,000 deaths annually in the U.S. alone and is frequently antibiotic-resistant. It’s a leading cause of pneumonia, bloodstream infections, bone/joint infections and surgical site infections and the #1 cause of skin and soft tissue infections. Efforts to develop an S. aureus vaccine have so far failed: the vaccines don’t seem to be capturing the right ingredients to make people immune.

Kristin Moffitt, MD, in Boston Children’s Hospital’s Division of Infectious Diseases, took a step back and asked: “What proteins does S. aureus need to make to establish infection?” The answer, she reasoned, could point to new antigens to include in a vaccine.

The above image shows an early result from Moffitt’s investigation. It’s a “heat map” of the messenger RNA signature — a snapshot of the proteins S. aureus is potentially up-regulating during infection.

Read Full Story | Leave a Comment

First reported cure of a baby infected with HIV

HIV (green dots) budding from a white blood cell. (CDC)

AIDS and HIV have been with us for more than 30 years. In that time, millions have died and millions more have been able to keep the virus at bay with a cocktail of medications called highly active antiretroviral therapy, or HAART.

But of those millions, only one person has reportedly been cured. As of this week, that number may now be two.

A team of researchers at Johns Hopkins University Medical School reported at last weekend’s Conference on Retroviruses and Opportunistic Infections the case of a child believed to be born HIV-positive and who, by all available tests, is no longer carrying active virus in the blood.

The key, according to their report, was aggressive and near immediate HAART treatment, starting before the child was 30 hours old and continuing until she was a year and a half old.

“This finding is hopeful but requires further study,” says Sandra Burchett, MD, MSc, clinical director of our Division of Infectious Diseases and director of the Children’s Hospital AIDS Program. “We all agree that treating babies infected with HIV as soon as possible maintains a healthy immune system; what we do not know is when, if ever, it is safe to stop HAART. Treating adults early after infection is not curative, but it may be that babies are somehow different.

“It is critically important, though,” she cautions, “for children, youth and young adults with HIV who are on HAART now to keep taking their medications, not stop on their own to see if they too are cured.”

Some question, though, whether the child was ever actually infected. Her doctors started therapy so early because her mother had uncontrolled HIV, putting the child at extremely high risk of developing the infection herself.

The only other patient reportedly ever cured of HIV is a man named Timothy Ray Brown. In 2006, Brown received a bone marrow transplant for leukemia, but with a twist: the marrow donor had been chosen for harboring a rare genetic mutation that conferred resistance to HIV. According to a paper published in the New England Journal of Medicine in 2009, Brown has been off HAART treatment since 2007 with little to no sign of infection.

Want to learn more? Click here to read an online Q&A with Burchett hosted by The Guardian on March 5.

Read Full Story | Leave a Comment