Navigation Links
The H1N1 flu vaccine protects both pregnant women and newly-borns
Date:12/7/2011

The researchers studied the immune response of 107 pregnant women after they were injected with a single dose of non-adjuvant H1N1 vaccine. They concluded that the influenza shot boosted the immune response in pregnant women and at the same time protected neuronatal babies via the antibodies that transferred through the placenta.

These results were published in the review Annals of Internal Medicine dated December 6th,.2011. They are available on-line at: http://www.annals.org/content/155/11/733.abstract

Influenza (the flu) is a contagious, acute respiratory infection caused by the family of viruses Influenzae. There are three types of Influenza virus: A, B and C. The A and B viruses cause seasonal (or winter) epidemics, but only the A virus is responsible for worldwide epidemics. Very soon into the worldwide influenza epidemic of 2009, pregnant women and neonatal babies were found to be at very high risk of complications and death if infected, as had already been observed during previous worldwide influenza epidemics. As early as August 2009, a study published in The Lancet showed that 10% of the serious cases were observed in pregnant women, whereas they represented only 1% of the total French population. So H1N1 influenza vaccination of pregnant women was recommended as a priority.

The team led by Odile Launey, the Director of vaccinology at the Centre for Clinical Investigation at Cochin Pasteur (Inserm/AP-HP/Institut Pasteur/Universit Paris Descartes), carried out a vaccination study in order to demonstrate the immunogenicity, in other words the immune response in terms of the production of antibodies, after a single injection of a nonadjuvant A strain (H1N1) into women at 21 days and 42 days of gestation and to measure the transplacentary transfer of the mother's antibodies to neonatal babies.

This study concerned 107 women between 22 and 32 weeks of amenorrhea who were monitored in 5 French neonatal clinics between November 3rd and December 4th 2009 after being injected into the arm with an injection of H1N1 A strain vaccine.

Blood tests were carried out in order to measure the antibody counts protecting against the influenza virus:

  • Piror to vaccination
  • 3 and 6 weeks after vaccination
  • At delivery
  • 3 months after delivery

On delivery, a blood sample is taken from the umbilical cord in order to measure the quantity of influenza antibodies transmitted to the newly born. All events observed in mothers and babies during the study were recorded.

Prior to vaccination, 19% of the patients already presented H1N1 strain antibodies at levels considered to be protective. Three and six weeks after vaccination, 98% of the patients presented blood antibody counts considered to be protective. On delivery and 3 weeks after delivery, the proportion of patients with antibody counts considered to be protective were between 92% and 90%. The umbilical cord samples of newly born babies showed antibody counts considered to be protective in 95% of cases, some antibody concentrations were even higher than in the mothers (a ratio of 1.4 between neonatal babies concentrations and maternal concentrations at delivery).

"These results show that the influenza vaccine boosts the immune system in pregnant women and also protects newly-borns via transplacenta transfer ", concludes Odile Launay.

This study and an increasing number of other studies on pregnant women have confirmed the non-toxicity of the influenza vaccine during pregnancy. This year again, pregnant women are strongly recommended to take the influenza vaccine. The composition of the vaccine is modified each year to cover the major strains of the previous winter, which are the strains most likely to be present the next winter. "The H1N1 2009 virus is still around. That's why the inactivated H1N1 virus is still present in the current seasonal influenza vaccine". So it is highly recommended to vaccinate pregnant women in order to protect them and their baby, because otherwise the vaccine cannot be administered to babies before the age of 6 months", explains Odile Launay.


'/>"/>
Contact: Inserm Presse
presse@inserm.fr
INSERM (Institut national de la sant et de la recherche mdicale)
Source:Eurekalert

Related biology news :

1. Childrens National researchers develop novel anti-tumor vaccine
2. RNA molecules, delivery system improve vaccine responses, effectiveness
3. Bird flu vaccine protects people and pets
4. Research identifies type of vaccine that holds promise in protecting against TB
5. UT Southwestern researcher awarded Gates Foundation grant for novel vaccine development
6. Flu shot protects kids -- even during years with a bad vaccine match
7. New type of vaccines deliver stronger and faster immune response
8. Fractional dose of scarce meningitis vaccine may be effective in outbreak control
9. Vaccines and autism: Many hypotheses, but no correlation
10. New vaccine developed for preventing uncommon cold virus
11. African-Americans aware and accepting, but often do not receive, the HPV vaccine
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/3/2016)... PUNE, India , February 3, 2016 ... to the new market research report "Automated Fingerprint Identification ... (Tenprint Search, Latent Search), Application (Banking & Finance, Government, ... 2020", published by MarketsandMarkets, the market is expected to ... estimated CAGR of 21.0% between 2015 and 2020. The ...
(Date:2/2/2016)... YORK , Feb. 2, 2016 /PRNewswire/ ... facilities are primarily focused on medical screening ... measure point-of-care parameters. Wearable devices that facilitate ... user,s freedom of movement are being bolstered ... for human biomedical signal acquisition coupled with ...
(Date:2/2/2016)... 2, 2016 Technology Enhancements Accelerate Growth of X-ray ... the digital and computed radiography markets in ... Indonesia (TIM). It provides an ... as well as regional market drivers and restraints. The ... penetration and market attractiveness, both for digital and computed ...
Breaking Biology News(10 mins):
(Date:2/12/2016)... MedGenome,s Commitment Will Help ... of Complex Diseases Such as Cancer, Metabolic Disorders, ... --> --> MedGenome, the market ... leading provider of genomics research services globally, today ... GenomeAsia 100K consortium as a founding member. ...
(Date:2/11/2016)... 2016  Bioethics International, a not-for-profit organization focused on the ... and made accessible to patients around the world, today announced ... the publication of the Good Pharma Scorecard an ... featured as one of BMJ Open ,s ,Most Popular ... are most frequently read. Ed Sucksmith , assistant ...
(Date:2/11/2016)... February 11, 2016 ... or "Company") (OTCQB: PSID), a life sciences company ... its Thermomedics subsidiary, which markets the Caregiver® FDA-cleared ... plan in January 2016, including entering into agreements ... monthly sales growth, and establishing several near-term pipeline ...
(Date:2/10/2016)... MONTREAL , Febr. 10, 2016 /PRNewswire/ - BioAmber Inc. ... is pleased to announce that Mitsui & Co. Ltd., ... bio-based succinic acid plant, is investing an additional CDN$25 ... equity, increasing its stake from 30% to 40%.  Mitsui ... of bio-succinic acid produced in Sarnia ...
Breaking Biology Technology: