Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers develop method to better estimate vaccine coverage

27.10.2011
Immunizations are a valuable tool for controlling infectious diseases among populations both in the U.S. and globally. Routine immunizations and supplemental immunization activities, such as immunization campaigns, are designed to provide immunization coverage to entire populations.

Current measurements used to determine the success and rates of immunization can be flawed and inconsistent. According to a new study led by researchers from the Johns Hopkins Bloomberg School of Public Health, estimates of vaccination coverage can be significantly improved by combining administrative data with survey data. The results are featured in the October 2011 issue of PLoS Medicine.

"Reliable estimates of vaccination coverage are key to managing population immunization status," said Justin Lessler, lead author of the study and an assistant professor with the Bloomberg School's Department of Epidemiology. "Currently, the performance of routine and supplemental immunization activities is measured by the administrative method, which leads to coverage estimates that are often inconsistent with the proportion reporting vaccination in cross-sectional surveys. Furthermore, administrative coverage does not tell you how many people are systematically missed by vaccination activities. We estimated that the size of the population never reached by any activity was high in Sierra Leone and Madagascar, 31 percent and 21percent respectively. But it was much lower in Ghana, only 7 percent. "

The widely used administrative method divides the number of doses distributed by the size of the target population. Lessler, along with colleagues from Johns Hopkins, University of Oxford, Epicentre, and Princeton University developed a method for estimating the effective coverage of vaccination programs using cross-sectional surveys of vaccine coverage combined with administrative data. The method was applied using demographic health survey and administrative coverage data reported to the WHO from measles vaccinations in Ghana, Madagascar and Sierra Leone. They found estimates of routine supplemental immunization activities coverage are substantially lower than administrative estimates for Madagascar and Sierra Leone, and only slightly lower for Ghana. In addition, their estimates of routine coverage are, in general, lower than WHO and United Nations Children's Fund (UNICEF) estimates.

"This method not only attempts to correct coverage estimates, but also distinguishes between issues of overall coverage and vaccine within activity inefficiencies. For our technique to be useful, countries must have cross-sectional data on vaccine coverage for children across a range of ages, some of an age where they have been exposed to multiple vaccination activities," said Derek Cummings.

"Estimates of the inefficiency of past vaccination activities and the proportion not covered by any activity allow us to more accurately predict the results of future activities and provide insight into the ways in which vaccination programs are failing to meet their goals," adds Lessler.

"Measuring the Performance of Vaccination Programs Using Cross-Sectional Surveys: A Likelihood Framework and Retrospective Analysis" was written by Justin Lessler, C. Jessica E. Metcalf, Rebecca F. Grais, Francisco J. Luquero, Derek A. T. Cummings and Bryan T. Grenfell.

This research was supported by grants from the Vaccine Modeling Initiative of the Bill and Melinda Gates Foundation, the Department for Homeland Security, the NIH, the Burroughs Welcome Fund and the Royal Society.

Natalie Wood-Wright | EurekAlert!
Further information:
http://www.jhsph.edu

Further reports about: BLOOMBERG Cummings Ghana Hopkins Madagascar vaccination programs

More articles from Health and Medicine:

nachricht Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Researchers release the brakes on the immune system

18.10.2017 | Health and Medicine

Separating methane and CO2 will become more efficient

18.10.2017 | Life Sciences

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>