Women with the HIV virus sometimes give birth to babies who are free of the virus. How is this possible?
My guess is that HIV doesn’t pass the placental barrier and that if infection is going to occur it happens during birth, after the bag of waters has broken. I know this is true of Strep B, another virus.
They get very lucky!
Exposure to a virus (or bacteria, for that matter) doesn’t guarantee you will get s the illness associated with that virus or bacterium, oonly that it’s possible - in some cases, extremely possible, but never 100% guaranteed.
I do wonder what the odds are in this case. I would guess that a baby being born of an AIDS infected mother would have around a 15% chance of not contracting the disease, with that number being higher if mom got infected well into the pregnancy, and lower if it was a case where she was infected all along, or by the guy and at the time of conception.
Yer pal,
Satan
http://www.raleighmusic.com/board/Images/devil.gif
TIME ELAPSED SINCE I QUIT SMOKING:
Three days, 21 hours, 59 minutes and 16 seconds.
156 cigarettes not smoked, saving $19.58.
Life saved: 13 hours, 0 minutes.
Are there no infectious fluids exchanged/shared between mother and child while the baby is in utero?
Congratulations on the non-smoking. You sure smoked a lot of cigs per day.
The phenomenon is called vertical transmission, and in untreated cases it generally runs about fifty percent infections, with HIV positive, non AIDS symptom mothers. But any woman who becomes pregnant, whatever her opinion on her HIV status would be very well advised to be tested, because proper treatment during pregnancy, and delivery can reduce that percentage by at least half, and in the proper environment of supports and health, single digits.
Get the information. Choose a reputable source and find the real facts. Net gossip is not a good way to learn about the Plague of the Millennium. (No offense meant to the Teeming Millions.)
Tris
Imagine my signature begins five spaces to the right of center.
A 1996 article:
JAMA - Advances in the Prevention and Treatment of Perinatal HIV Infection
HIV can also be transmitted post-natally through breastfeeding. Here is a 1996 study.
JAMA - HIV Transmission Through Breastfeeding - A Study in Malawi
oops! - simulpost. Well, it never hurts to have more information.
Viral infections generally need more than one virus particle to get started. If the viral load is small enough, the immune system can generally take care of it. Don’t forget, babies get antibodies from their mothers as well as viruses. So the baby of an HIV+ mother is primed against HIV.
Also, because retroviruses mutate so quickly, a significant precentage of viral particles floating around are duds.
Thank you Arnold, I will add the main site to my list of reputable sources of info on AIDS.
Tris
Imagine my signature begins five spaces to the right of center.
Hmmm…are there no HIV babies? Not sure.
A better question would be to ask if this is STILL true after the first child? As I understand it, the Rh factor issue does not put the first baby at risk…only subsequent babies. My medical texts gives a good explanation for this too lengthy to touch on here.
I will re-read, but I believe it is only the subsequent pregnancies which can be at risk. I can’t see why HIV would be any different.
“They’re coming to take me away ha-ha, ho-ho, hee-hee, to the funny farm where life is beautiful all the time… :)” - Napoleon IV
Well, let’s see, how are HIV, and RH antibody Maternal/fetus conflict different?
In the case of RH conflict the problem is the mother’s antibodies attacking the fetal tissues, after being sensitized during a prior pregnancy from an RH incompatible father. In the other you have an active external pathogen, a virus, which is sometimes able to cross the placental barrier, and sometimes able to infect the infant during birth, or during exchanges of body fluids during nursing.
Both problems do involve the immune system, and a mother and a child. After that, I am not sure why you think there is much in the way of similarity.
By the way, RH incompatibility can be easily controlled, resulting in no specific disabilities for the infant in the overwhelming nmber of cases. AIDS is still incurable, and fatal.
Tris
Imagine my signature begins five spaces to the right of center.
Also, It is not viral load or anything that is a factor. From wehat I’ve read, it more of a strain-subtype issue.
In west Africa, where there is much HIV-2, 90% of babies born to mothers who are infected are infected Perinatally. I don’t believe HIV-1 and it’s straind are this good yet.
So, it’s not viral load(because in the case of HIV-2 the viral load is low and does not readily kill it’s host), but it’s more of a preferred method of transmission.
HIV-1 seems to prefer the Langerhans cells of the anus and vagina.
And also the Langerhans cells of the penile foreskin according to recent work by Professor Roger Short et al.
Tris, the fact that Rh and HIV are two different things AND the fact that Rh has treatment are irrelevant factoids. (By the way, Rh factor untreated is fatal, too.)
You’re trying to split hairs here, by the body doesn’t disciminate! Whatever is in the mother’s blood can be passed along into the bloodstream of the subsequent fetus. The mother’s blood cannot pass or mix with the blood of the first fetus. However, for subsequent preganancies, the blood MAY mix which is why Rh treatment is necessary.
The Rh factor has to do with incompatable blood characteristics between mother and fetus. (It is not an attack of all fetal tissues…only blood. Of course, the other tissues suffer the consequences.)
Thus, the mere fact that mother and (subsequent) fetus blood can mix, there is clearly no reason to doubt that whatever is carried by the mother can mix with the bloodstream of the fetus as well.
“They’re coming to take me away ha-ha, ho-ho, hee-hee, to the funny farm where life is beautiful all the time… :)” - Napoleon IV
[[Also, It is not viral load or anything that is a factor. From wehat I’ve read, it more of a strain-subtype issue.]]
No, viral load* is* important. Women with higher viral loads are more likely to pass on the virus to their infants. There are other co-factors, but this is one of them.
[[In west Africa, where there is much HIV-2, 90% of babies born to mothers who are infected are infected Perinatally. I don’t believe HIV-1 and it’s straind are this good yet. So, it’s not viral load(because in the case of HIV-2 the viral load is low and does not readily kill it’s host), but it’s more of a preferred method of transmission.
This is inaccurate. There are many substrains of HIV-1 and there are theories about differences in transmissibility beteen them. HIV -II is distant enough from type 1 as to be almost unrelated.
For more info., check out http://hivinsite.ucsf.edu
Jill