WHAT'S NEW: THE ISRAEL NATIONAL IMMUNIZATION REGISTRY; WORLDWIDE INCIDENCE OF MALARIA IN 2009; GENDER EQUALITY AND DEVELOPMENT

Friday, 20th of January 2012

• THE ISRAEL NATIONAL IMMUNIZATION REGISTRY

The full text of this article, at http://www.ima.org.il/imaj/ar10may-11.pdf , includes a table describing immunization registries from 11 developed countries. If the datasets needed for such registries are available in middle income countries, why can’t these countries do likewise?

• WORLDWIDE INCIDENCE OF MALARIA IN 2009

One method:‘population-based surveys of Plasmodium prevalence and case incidence from selected locations in malaria endemic areas.’

http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1001142

Editors' Summary 

Background

Malaria is a life-threatening disease caused by the Plasmodium parasite, which is transmitted to people through the bites of infected mosquitoes. According to latest estimates from the World Health Organization (WHO), in 2009, there were 225 million cases of malaria and an estimated 781,000 deaths worldwide—most deaths occurring among children living in the WHO African Region (mainly sub-Saharan Africa). Knowing the burden of malaria in any country is an essential component of public health planning and accurately estimating the global burden is essential to monitor progress towards the United Nations' Millennium Development Goals.

Currently, there are generally two approaches used to estimate malaria incidence:

One method uses routine surveillance reports of malaria cases compiled by national health ministries, which are analyzed to take into account some deficincies in data collection, such as incomplete reporting by health facilities, the potential for overdiagnosis of malaria among patients with fever, and the use of private health facilities or none at all. The second method uses population-based surveys of Plasmodium prevalence and case incidence from selected locations in malaria endemic areas and then uses this information to generate risk maps and to estimate the case incidence of malaria per 1,000 population, for all of the world's malaria endemic regions. The Malaria Atlas Project—a database of malaria epidemiology based on medical intelligence and satellite-derived climate data—uses this second method.

Why Was This Study Done?

In order for malaria epidemiology to be as accurate as possible, an evaluation of the strengths and weaknesses of both methods is necessary. In this study, the researchers analyzed the merits of the estimates calculated by using the different approaches, to highlight areas in which both methods need to be improved to provide better assessments of malaria control.

What Did the Researchers Do and Find?

The researchers estimated the number of malaria cases in 2009, for each of the 99 countries with ongoing malaria transmission using a combination of the two methods. The researchers used the first method for 56 malaria endemic countries outside the WHO African Region, and for nine African countries which had the quality of data necessary to calculate estimates using the researchers statistical model—which the researchers devised to take the upper and lower limits of case detection into account. The researchers used the second method for 34 countries in the African Region to classify malaria risk into low-transmission and high-transmission categories, and then to derive incidence rates for populations from observational studies conducted in populations in which there were no malaria control activities. For both methods, the researchers conducted a statistical analysis to determine the range of uncertainty.

The researchers found that using a combination of methods there was a combined total of 225 million malaria cases, in the 99 countries malaria endemic countries—the majority of cases (78%) were in the WHO African region, followed by the Southeast Asian (15%) and Eastern Mediterranean regions. In Africa, there were 214 cases per 1,000 population, compared with 23 per 1,000 in the Eastern Mediterranean region, and 19 per 1,000 in the Southeast Asia region. Sixteen countries accounted for 80% of all estimated cases globally—all but two countries were in the African region. The researchers found that despite the differences between methods 1 and 2, the ratio of the upper and lower limit for country estimates was approximately the same.

What Do These Findings Mean?

Using the combined methods, the incidence of malaria was estimated to be lower than previous estimates, particularly outside of Africa. Nevertheless the methods suggest that malaria surveillance systems currently miss the majority of cases, detecting less than 10% of those estimated to occur globally. Although the best assessment of malaria burden and trends should rely on a combination of surveillance and survey data, accurate surveillance is the ultimate goal for malaria control programs, especially as routine surveillance has advantages for estimating case incidence, spatially and through time. However, as the researchers have identified in this study, strengthening surveillance requires a critical evaluation of inherent errors and these errors must be adequately addressed in order to have confidence in estimates of malaria burden and trends, and therefore, the return on investments for malaria control programs.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1​001142.

This study is further discussed in a PLoS Medicine Perspective by Ivo Mueller and colleagues

The WHO provides information on malaria and produces the World Malaria Report each year, summarizing global progress in malaria control

More information is available on The Malaria Atlas Project

• GENDER EQUALITY AND DEVELOPMENT

Summarized at

http://siteresources.worldbank.org/INTWDR2012/Resources/7778105-1299699968583/7786210-1315936231894/Overview-English.pdf

This year’s World Development Report highlights the role of gender development in social and economic development. See the discussion of mortality, pp. 14-17.

‘The rate at which girls and women die relative to men is higher in low- and middle-income countries than in high-income countries. To quantify this excess female mortality (“missing” girls and women) and identify the ages at which it occurs, this Report estimated the number of excess female deaths at every age and for every country in 1990, 2000, and 2008. Excess female deaths in a given year represent women who would not have died in the previous year if they had lived in a high-income country, after accounting for the overall health environment of the country they live in. Globally, excess female mortality after birth and “missing” girls at birth account every year for an estimated 3.9 million women below the age of 60. About two-fifths of them are never born, one-fifth goes missing in infancy and childhood, and the remaining two-fifths do so between the ages of 15 and 59 (table 1).

‘Growth does not make the problem disappear. Between 1990 and 2008, the number of missing girls at birth and excess female mortality after birth did not change much; declines in infancy and childhood were offset by dramatic increases in Sub-Saharan Africa in the reproductive ages. Part of the increase is because populations increased. But, unlike Asia, where the population-adjusted missing women fell in every country (dramatically in Bangladesh, Indonesia, and Vietnam), most Sub-Saharan countries saw little change in the new millennium. And in the countries hardest hit by the HIV/AIDS epidemic, things got much worse.’

Until governments and partners put enough resources into gender equality, achievement of MDG 3, MDG4 and MDG5 is likely to lag.

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