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Montreal Gazette
Rapid saliva test helps block HIV virus
McGill University Researchers treat pregnant women in rural
India, where pediatric AIDS is a major problem
AARON DERFEL
The Gazette
Tuesday, May 06, 2008
Researchers at McGill University have field-tested in India a rapid saliva test for HIV that was shown to be highly effective in preventing
transmission of the virus from HIV-positive mothers to their children.
Pediatric AIDS continues to pose a major problem in rural India. All too frequently, pregnant women who are infected with HIV but don't
know it unwittingly transmit the virus to their child during birth.
The World Health Organization reported last year that 420,000 children were newly infected with the human immunodeficiency virus, most
of the infections occurring as a result of mother-to-child transmission.
Anti-retroviral drugs given to an HIV-exposed infant after birth do succeed in preventing infection. But the problem is that a pregnant
woman must be tested either before or during labour - and that often doesn't happen in India, one of the McGill researchers said.
"In rural India, most women do not show up for testing before birth because of stigma and discrimination," said Nikita Pant Pai, of the
division of infectious diseases at the McGill University Health Centre. "As a result, they show up during labour without a history of HIV
testing. So at that point, it's important to know their status to intervene and prevent transmission."
Standard blood-test kits do exist in India, but they're often not available. It can take two hours to get the results, and laboratory
technicians are not on call at night to carry out the tests. Consequently, most women give birth without ever having been tested.
Pai and her colleagues decided to try an HIV oral test, which has been shown to be just as accurate as the blood exam, but much quicker
and easier to carry out. The OraQuick test was approved by the United States Food and Drug Administration in 2004.
During a nine-month period, 1,222 women underwent oral testing in the labour ward in a hospital in the central Indian town of Wardha. Of
that number, an astonishing 82 per cent of the women had never been tested for HIV.
Pai inserted what looks like a candy stick into the mouths of the women to collect saliva from their gums. If a woman is infected, the saliva
would contain high concentrations of HIV antibodies. Unlike blood tests, the results were known within 20 minutes.
The labour-ward screening did reveal that 11 women had been infected with HIV, and none had been previously tested. Of the 11 births, 10
babies not only survived but were HIV-negative - thanks to the administration of anti-retroviral drug cocktails.
Pai suggested the saliva test is a much better tool in preventing mother-to-child transmission than the blood test and should become
standard procedure in India as well as in South Africa and China, where pediatric AIDS is a threat.
"We demonstrated that even in a rural, resource-constrained setting, if you employ counsellors and administer an HIV test, you can reduce
transmissions," she said.
And the saliva test's advantage is that it doesn't have to be done by a lab tech.
The study's findings, to be published today in the open access online journal of the Public Library of Science, could have Canadian
applications. That's because pregnant women from marginalized immigrant communities don't often get blood tests before they give birth,
Pai noted.
Statistics appear to confirm that observation. The number of HIV-exposed infants in this country has increased steadily to 173 in 2005 from
87 in 1993, according to the Canadian Perinatal HIV Surveillance Program.
Fortunately, the proportion of HIV-infected infants has dropped to four per cent in 2005 from 39.5 per cent in 1994 - largely as a result of
HIV-positive pregnant women receiving anti-retroviral therapy.
"I was under the impression that HIV testing during pregnancy is religiously done in Canada, but I was surprised that it's not always the
case," Pai said.
[email protected]
© The Gazette (Montreal) 2008
Copyright © 2008 CanWest Interactive, a division of CanWest MediaWorks Publications, Inc.. All rights reserved.
CanWest Interactive, a division of CanWest MediaWorks Publications, Inc.. All rights reserved.
VIH/sida : Un test oral de dépistage | Science et santé | Radio-Canada.ca
Page 1 of 1
Science et santé
Mise à jour le jeudi 12 avril 2007 à 10 h 15
VIH/sida
Un test oral de dépistage
Rapide et efficace. Voilà les principales qualités d'un nouveau test oral de dépistage du VIH mis au point
par des chercheurs du Centre universitaire de santé McGill (CUSM), à Montréal.
Il offrira une solution de rechange au traditionnel test sanguin, dont les résultats peuvent prendre jusqu'à
deux semaines avant d'être communiqués au patient.
Les résultats de ce test oral seraient disponibles dans un délai de 40 minutes.
Photo: Getty
La nouvelle procédure pourrait même devenir la nouvelle norme en matière de test de terrain, selon une
étude menée par le CUSM.
Les travaux montrent que le test OraQuick HIV-1/2, administré oralement sur le fluide oral, assure une précision de 100 % et constitue
l'option privilégiée des patients.
Le test oral du VIH peut également être administré par un personnel sanitaire possédant une formation minimale, ce qui supprime le
besoin de techniciens de laboratoire spécialisés. — Dre Nitika Pai
L'auteure principale de cette recherche, la Dre Nitika Pai et ses collègues ont testé 450 personnes pour l'infection au VIH à l'Institut des
sciences Mahatma Gandhi de Sevagram, en Inde. Ils ont établi que 32 % des personnes testées présentaient des résultats positifs au VIH.
Les chercheurs ont comparé la précision diagnostique du test OraQuick à l'aide de deux échantillons, le premier prélevé sur le fluide oral et
le second, par piqûre au doigt, aux tests sanguins classiques.
De plus, le test pratiqué sur le fluide oral était précis à 100 % en comparaison de la ponction sanguine au doigt, qui a produit un faux
résultat positif (spécificité de 99,7 %). Pour le test oral, peu d'inconfort a été signalé au cours du prélèvement des échantillons, alors que
66 % des sujets soumis à la ponction au doigt ont signalé un inconfort.
Le test oral avait déjà reçu l'aval de la Food and Drug Administration des États-Unis. Toutefois, des études antérieures indiquaient que ce
test manquait de précision. Pour cette raison, le Centre for Disease Control a réclamé des études plus concluantes, ce qui a conduit aux
tests supplémentaires en Inde.
© Société Radio-Canada. Tous droits réservés.
http://www.radio-canada.ca/nouvelles/Science-Sante/2007/04/12/001-VIH-sida-test-oral.shtml
4/24/2007
Now, gum swab to spot HIV-India-The Times of India
Printed from
Page 1 of 1
The Times of India -Breaking news, views. reviews, cricket from
across India
Now, gum swab to spot HIV
7 May 2008, 0209 hrs IST, Kounteya Sinha, TNN
NEW DELHI: A simple gum swab in place of an invasive blood test can now tell whether you are HIV positive.
What's even better, the test results will be out in just 10-20 minutes.
In a breakthrough that could replace the present day HIV antibody test through blood taken from the finger or the
arm, a team of Indo-Canadian scientists has successfully tested the world's first saliva-based HIV test, with an
accuracy rate of nearly 100%.
The final results from the study, conducted in Maharashtra in 2006, by a team from McGill University Health
Centre (MUHC), Canada, and Mahatma Gandhi Institute of Medical Sciences (MGIMS), Sevagram, were
published on Tuesday in the international medical journal ‘PloS Medicine'.
This test is based on oral mucosal transudate (OMT), a fluid that is secreted at the base of the gums before it
becomes saliva.
Scientists found that the level of antibodies in OMT is comparable to that of blood plasma, making it an excellent
sample for HIV testing.
Lead author Nitika Pant Pai from MUHC's division of infectious diseases, said this new technique would do away
with blood collection, which scares away patients from undergoing HIV test. The team now hopes that this
research will pave the way for widespread use of oral HIV tests available over-the-counter.
Rai conducted clinical trials on vulnerable pregnant women in the labour ward of MGIMS. She said that
extracting blood in field settings poses a logistical problem because it needs injecting syringes and trained
personnel. Now, all that one has to do is rub the stick against the gum twice to collect oral fluid.
"The applicator on the stick, a strip of synthetic proteins, then detects HIV antibodies in 20 minutes or less.
Standard blood test for HIV takes up to two weeks," Dr Pai said. She added that in India, it is vital to determine
the HIV status of mothers very quickly to prevent transmission to the child during delivery.
"Over 50% Indian women do not receive prenatal care and therefore don't get tested for HIV during pregnancy.
Testing in the labour ward is the last chance to prevent HIV transmission to the newborn baby. Also Indian
patients often refuse blood collection in fear of social ostracization, while saliva collection poses no problem.
Thanks to this test, women were enrolled, received counselling, their test results confirmed and referred for
treatment when found positive, within 40-60 minutes," she said.
Globally, in 2007, about 2.1 million children were detected with new HIV infection - 90% of them having acquired
it via maternal fetal transmission.
Without rapid and accurate detection of HIV, no delivery of available PMTCT interventions (prevention of mother
to child HIV transmission) is possible. Without anti-retroviral drugs, the probability of transmission is 30-35%.
With ART, it is reduced to 10-15%.
"In the labour room, due to inconsistent supply of blood-based rapid tests, they are often not available. Thus,
many fail to get tested. In India, 4,755 infants were detected in 2005 attributed to mother-to-child transmission,"
Pai added.
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5/10/2008
Universal rapid HIV testing during labor feasible in developing countries | Reuters | HME... Page 1 of 2
News
Public Health
Normal Version
Universal rapid HIV testing during labor feasible in
developing countries
by C. Vidya Shankar, MD
Last Updated: 2008-05-09 14:47:55 -0400 (Reuters Health)
CHENNAI, India (Reuters Health) - Rapid oral-fluid testing for HIV, counseling, and mother-to-child transmission (MTCT)
prophylaxis in all women at the time of delivery are feasible and cost-effective in resource-poor settings, according to the
results of a study from India.
A large proportion of women in resource-poor settings do not have access to antenatal care and miss out on HIV testing
and MTCT prevention measures during pregnancy, note Dr. Nitika Pant Pai and colleagues. "Delivery is the last
opportunity."
Dr. Pai, from McGill University in Montreal, Canada, and her associates introduced round-the-clock rapid HIV testing in a
busy labor ward at the Mahatma Gandhi Institute of Medical Sciences, Wardha, in central India.
The team offered 1252 women two rapid HIV tests, one using oral fluid and the other through finger blood samples, and
1222 women consented. When one or both tests were positive, results were confirmed with dual ELISA Western blot tests.
Women testing positive were given rapid prepartum counseling for around 15 minutes, postpartum counseling and MTCT
prophylaxis intrapartum and postpartum as per existing protocols. Their infants received antiretrovirals in the first week
postpartum and HIV RNA testing within 2 days postpartum, at 1 month and 4 months of age.
Fifteen women in the study group tested HIV positive, the researchers report in the May issue of PLoS Medicine.
Intrapartum and postpartum MTCT prophylaxis was administered to 14 women, while 1 woman received only postpartum
prophylaxis because of initial negative tests, they note.
Two infants born to HIV-positive mothers were HIV RNA positive at 48 hours postpartum and did not survive the neonatal
period, while the remaining 13 were HIV-negative at the end of 4 months, the researchers found.
The diagnostic accuracy of both the rapid tests was the same, with a sensitivity of 93.3% and specificity of 100%, Dr. Pai's
team observed.
The complete process from testing to MTCT prevention took less than an hour, which is feasible in most delivery centers,
they add.
"It is possible to use one oral test and confirm it with ELISA and Western Blot, or use two rapid tests of different antigenic
specificities in a serial or parallel testing format, which is recommended by WHO. The novelty of oral testing is the
convenience, to the patient, the physicians, the counselors," Dr. Pai told Reuters Health.
When asked about the feasibility of implementation on a large scale, Dr. Pai said, "Yes, it is doable." The resources needed
"are nominal, if you consider the long-term resources needed to treat HIV-infected children," she added.
"A large number of women first encounter the medical care system during active labor," Dr. David D. Celentano from the
Johns Hopkins Bloomberg School of Public Health and author of a related editorial told Reuters Health. "The only
opportunity for HIV testing is during labor and delivery," he said.
http://www.hmetoday.com/reuters_article.asp?mode=print&id=20080509publ001.html
5/10/2008
Universal rapid HIV testing during labor feasible in developing countries | Reuters | HME... Page 2 of 2
"Scaling up this program is clearly the next challenge," he commented.
PLoS Med 2008;5:e92,e107.
Copyright Reuters 2008. Click for Restrictions
http://www.hmetoday.com/reuters_article.asp?mode=print&id=20080509publ001.html
5/10/2008