Sunday, March 6, 2011

Baby contracts Yellow Fever from vaccinated mother through breastfeeding

A baby contracted Yellow Fever through breastfeeding after the mother was vaccinated for Yellow Fever in anticipation of a trip to Venezuela. As you would expect, the yellow fever vaccine is live attenuated. Doctor’s recommend that women do not breastfeed after receiving the vaccine because of the assumed risk. As a result, this case showing a link between breastfeeding and contraction of the disease by the child is the first. Obviously, mothers should steer clear of live vaccines when breastfeeding. As we’ve learned, an inactivated vaccine cannot become infectious and would therefore pose less risk for breastfeeding babies. This confirms one more issue to add to our pros and cons of live-attenuated and inactivated vaccines.
However, just to be on the safe side, doctors recommend that parents avoid traveling with children until their child is old enough to be vaccinated.


Protein of Hepatitis B inhibits repair of DNA

Protein X of Hepatitis B virus has diverse cytopathic effects. Specifically, it affects DNA helicase, a basal transcription factor, and DNA repair. This viral protein, while not required for infection has been linked to liver cancer. According to a recent study, protein X interferes with the action of TFIIH, a transcription factor that also takes part in DNA repair. By preventing the repair of DNA in this manner, protein X causes errors to build up. Damage to DNA is not caused by protein X itself, but rather prevents it from being fixed. This finding presents another target for prevention of Hepatitis B related hepatocellular carcinoma. Facilitating DNA repair should counteract liver cancer caused by hepatitis B.