Featured Research

from universities, journals, and other organizations

HPV vaccine provides significant protection against cervical abnormalities

Date:
March 4, 2014
Source:
BMJ-British Medical Journal
Summary:
The HPV vaccine offers significant protection against cervical abnormalities in young women, suggests a new paper. Results of the new study, the data concludes a risk reduction of 46% for confirmed high grade cervical abnormalities and 34% for other cervical abnormalities for young women who were fully vaccinated with the HPV vaccine prior to their first smear test.

The HPV vaccine offers significant protection against cervical abnormalities in young women, suggests a paper published on bmj.com today. The human papillomavirus (HPV) can cause warts, with some strains causing cervical cancer.

Australia was the first country to implement a publicly funded national vaccination program in April 2007 and a 'catch-up' program that ran until December 2009.

Studies have shown that the two HPV vaccines used to vaccinate young women prevent cervical lesions associated with HPV types including vulval and vaginal lesions and genital warts in women as well as genital warts and high grade anal disease in men.

While clinical trials have demonstrated the effectiveness of the vaccine, little is known about the vaccine's effectiveness when delivered to a broader population. Researchers from Australia therefore looked to measure the effectiveness of the HPV vaccine against cervical abnormalities, four years after implementation in Queensland, Australia. The primary objective was to "estimate the effectiveness of the quadrivalent vaccine in the population of sexually naοve young women with no prior infection."

Data was used from population registers in Queensland for a four year period following the introduction of the vaccination program in 2007. The study population included all female Queensland residents who attended for their first ever smear test between 2007 and 2011.

Two case groups were identified: the 'high grade cases' were women whose smear test and follow up biopsy confirmed a high grade cervical abnormality (precancer) and 'other cases' were women who did not meet the high grade case definition but had other abnormalities. 'Control' status was assigned to all remaining women whose results came back negative following their smear.

In total, 103,353 women were eligible for inclusion: 1062 high grade cases; 10,887 other cases and 96,404 controls. Women in the 'cases' group were older, more disadvantaged and less likely to live in major cities than women in the 'controls' group. 11% of high grade cases, 19% of other cases and 24% of controls were fully vaccinated. Fully vaccinated women were younger at first vaccine dose than partially vaccinated women.

Four years after the introduction of a routine and catch up HPV vaccination program, the researchers estimate, after adjusting for demographic factors that differed between the groups, that three doses of the vaccine provided 46% protection against high grade cervical abnormalities and 34% protection against other cervical abnormalities in women who had not commenced screening prior to vaccination. The researchers also found that two doses of the vaccine provided 21% protection against both high grade and other cervical abnormalities. There was no significant protection from one dose.

In the population studied, the number of women that need to be vaccinated with three doses in order to prevent one cervical abnormality at first screening round was 125 for a confirmed high grade abnormality and 22 for other abnormalities. They also found that the number needed to vaccinate to prevent one high grade cervical abnormality was significantly lower among women with a prior screening history than women with no prior screening history. The researchers believe this is because the incidence of high grade abnormalities is higher in this group of women.

The researchers also found that vaccine effectiveness was lower in the population of women who'd had one or more smear tests before their index date (the date of the abnormal smear test) compared with women who had no smear test. This is probably because women who were already screening were already sexually active, so therefore more likely to be infected with HPV, prior to vaccination. High grade cases in particular were significantly more likely to have had one or more prior tests.

In conclusion, the data suggests a risk reduction of 46% for confirmed high grade cervical abnormalities and 34% for other cervical abnormalities for young women who were fully vaccinated with the HPV vaccine prior to their first smear test. The researchers say that "continued observation of this population is necessary to assess the implications for cervical screening recommendations in the coming era of mass vaccination."


Story Source:

The above story is based on materials provided by BMJ-British Medical Journal. Note: Materials may be edited for content and length.


Journal Reference:

  1. E. Crowe, N. Pandeya, J. M. L. Brotherton, A. J. Dobson, S. Kisely, S. B. Lambert, D. C. Whiteman. Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: case-control study nested within a population based screening programme in Australia. BMJ, 2014; 348 (mar04 2): g1458 DOI: 10.1136/bmj.g1458

Cite This Page:

BMJ-British Medical Journal. "HPV vaccine provides significant protection against cervical abnormalities." ScienceDaily. ScienceDaily, 4 March 2014. <www.sciencedaily.com/releases/2014/03/140304102422.htm>.
BMJ-British Medical Journal. (2014, March 4). HPV vaccine provides significant protection against cervical abnormalities. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2014/03/140304102422.htm
BMJ-British Medical Journal. "HPV vaccine provides significant protection against cervical abnormalities." ScienceDaily. www.sciencedaily.com/releases/2014/03/140304102422.htm (accessed July 29, 2014).

Share This




More Health & Medicine News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Generics Eat Into Pfizer's Sales

Generics Eat Into Pfizer's Sales

Reuters - Business Video Online (July 29, 2014) — Pfizer, the world's largest drug maker, cut full-year revenue forecasts because generics could cut into sales of its anti-arthritis drug, Celebrex. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Nigeria Ups Ebola Stakes on 1st Death

Nigeria Ups Ebola Stakes on 1st Death

Reuters - Business Video Online (July 29, 2014) — Nigerian authorities have shut and quarantined a Lagos hospital where a Liberian man died of the Ebola virus, the first recorded case of the highly-infectious disease in Africa's most populous economy. David Pollard reports Video provided by Reuters
Powered by NewsLook.com
Running 5 Minutes A Day Might Add Years To Your Life

Running 5 Minutes A Day Might Add Years To Your Life

Newsy (July 29, 2014) — According to a new study, just five minutes of running or jogging a day could add years to your life. Video provided by Newsy
Powered by NewsLook.com
Ebola Outbreak Poses Little Threat To U.S.: CDC

Ebola Outbreak Poses Little Threat To U.S.: CDC

Newsy (July 29, 2014) — The Ebola outbreak in West Africa poses little threat to Americans, according to officials with the Centers for Disease Control and Prevention. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins