HIV - 英语听力.mp3

[00:00.00]From VOA Learning English,
[00:02.59]this is the Health Report.
[00:05.48]Hundreds of thousands of children
[00:08.40]become infected with the AIDS virus every year.
[00:13.02]These boys and girls are born to mothers who have HIV,
[00:18.01]the human immunodeficiency virus.
[00:21.44]Infection takes place during pregnancy
[00:24.79]or from breastfeeding.
[00:27.60]Recently, Scientists identified a protein
[00:32.31]in breast milk that suppresses the virus,
[00:35.97]the protein may even protect babies
[00:39.36]from become infected.
[00:41.72]Now, Experts say the discovery could lead to new ways
[00:46.67]to protect babies whose mothers are infected with HIV.
[00:51.77]To prevent Infection, doctors give Anti-retroviral drugs
[00:57.79]to both mothers and their babies,
[01:00.88]that has greatly reduced the number of infections.
[01:04.84]But experts say that even without anti-AIDS drugs,
[01:10.68]only a small percentage of babies
[01:13.68]become infected through breast milk.
[01:16.63]Sallie Permar is a professor of pediatrics and immunology
[01:22.19]at Duke University in North Carolina.
[01:25.96]She says, breastfeed babies appear to resist infection.
[01:31.71]"It is actually remarkable that despite
[01:34.85]the infant being exposed to the virus multiple times daily
[01:38.29]for up to two years of their life,
[01:41.57]actually only 10 percent of those babies
[01:43.82]will become infected," said Permar.
[01:45.31]The low rate of the infection
[01:47.47]was of great interest to researchers,
[01:50.13]including Sallie Permar.
[01:52.52]She led an effort to identify a substance in breast milk
[01:57.98]that may protect babies from infection.
[02:01.19]Her team directed its attention to a protein
[02:05.24]called Tenacin-C, also called TNC.
[02:10.71]It is known to be involved in the process of healing wounds.
[02:15.62]But what purpose it serves in breast milk is not known.
[02:21.27]The researchers exposed the TNC protein
[02:25.48]from breast milk of uninfected women to HIV,
[02:29.99]the protein linked up to the virus and made it harmless.
[02:34.94]Antiretroviral drugs remain effective
[02:39.04]in limiting the passing of HIV from mother to baby.
[02:44.25]But professor Permar and her team suggest
[02:49.15]the TNC could be used in places
[02:52.65]where costly drug treatments are often not available.
[02:57.66]"The issues are access to the drugs as well as monitoring.
[03:03.16]There are issues of toxicity and anti-retroviral drug resistance.
[03:07.73]And so we think alternative strategies
[03:11.49]may be needed to completely eliminate infant transmission," she Permar.
[03:14.44]She suggests that TNC could be given to babies
[03:20.35]before breastfeeding to provide additional protection against HIV.
[03:27.15]She adds that the protein is safe,
[03:30.59]because it is already in natural part of human milk.
[03:35.10]This may avoid the problem of HIV
[03:38.69]become resisted to Antiretroviral drugs.
[03:42.89]The team reported its findings in the journal
[03:46.65]Proceedings of the National Academy of Sciences.
[03:50.61]And that is the Health Report from VOA Learning English.
[03:55.90]I'm June Simms.