FRIDAY, Sept. 28, 2007 (HealthDay News) -- The deadly H5N1 bird flu virus can pass through the placenta of pregnant women and into the fetus, Chinese scientists report.
They also discovered that the virus infects organs other than lungs in adults.
The researchers, from Peking University in Beijing, analyzed tissue samples taken from two people -- a man and a pregnant women -- killed by bird flu, to determine how the virus affects different body organs.
They detected H5N1 genetic material and antigens in the lungs, certain cells in the trachea, the T-cells of the lymph node, neurons in the brain, and in cells of the placenta. They also found H5N1 genetic material in the intestinal mucosa but did not find any antigens there.
The dead woman's fetus had H5N1 genetic material and antigens in the lungs, circulating cells of the immune system, and in cells of the liver.
The findings are published in this week's issue of The Lancet medical journal.
"This study has shown the capacity for human vertical transmission of the H5N1 virus" and this "warrants careful investigation, since maternal infections with common human influenza virus are generally thought not to infect the fetus," the researchers wrote.
This and the finding that H5N1 spreads beyond the lungs in adults "are important in the clinical, pathological and epidemiological investigation of human H5N1 infection, and have implications for public health and health care providers."
The World Health Organization has more about bird flu.