WHAT'S NEW THIS TUESDAY: ENDING PREVENTABLE CHILD DEATHS; PNEUMOCOCCAL NASOPHARYNGEAL CARRIAGE AMONG PCV-7 VACCINEES; ARI BURDEN IN CRISIS AFFECTED POPULATIONS

Monday, 18th of June 2012

• WHAT’S NEW: WHO/UNICEF ON ENDING PREVENTABLE CHILD DEATHS; PNEUMOCOCCAL NASOPHARYNGEAL CARRIAGE AMONG PCV-7 VACCINEES; THE BURDEN OF ARIs IN CRISIS AFFECTED POPULATIONS

• WHO/UNICEF ON ENDING PREVENTABLE CHILD DEATHS

outline goes here

The Lancet, Volume 379, Issue 9832, Pages 2119 - 2120, 9 June 2012

Towards ending preventable child deaths

Original Text

Margaret Chan a, Anthony Lake b

Thanks in large part to the increased attention to maternal and child survival brought about by the Millennium Development Goals (MDGs),1 the world has made substantial progress in reducing child mortality over the past two decades. The number of deaths among children younger than 5 years has declined from more than 12 million in 1990 to 7·6 million in 2010.2 The mortality rate in children under 5 years has dropped from 88 deaths per 1000 livebirths in 1990 to 57 in 2010—a 35% reduction.2 The rate of decline in the under 5 mortality rate has accelerated from 1·9% a year from 1990 to 2000 to 2·5% a year from 2000 to 2010.2 The rate of reduction has doubled in sub-Saharan Africa.2 These gains underline the importance of having clearly defined targets, especially when they are combined with mechanisms for monitoring progress, ensuring equity, and promoting accountability.

Despite these impressive gains, every year 7·6 million children still die before their fifth birthday. Two-thirds of child deaths in 2010 were due to infectious causes, nearly all of which were preventable through cost-effective interventions, such as breastfeeding and vaccination.3 An additional high proportion of child deaths result from such causes as preterm birth, perinatal asphyxia, injuries, and congenital anomalies,3 for which interventions already exist, for example, family planning and care during pregnancy and delivery. If the world mobilises to ensure that children in low-income and middle-income countries have access to all the interventions for maternal, newborn, and child care that have reduced child mortality in high-income countries, we could put an end to preventable child deaths.

The time has arrived to commit fully to this ambitious but attainable goal. On June 14—15, 2012, policy makers and leaders from civil society, academia, and industry will gather at the Child Survival Call to Action in Washington, DC, USA—a high-level forum co-convened by the Governments of Ethiopia, India, and the USA. The event will launch Committing to Child Survival: A Promise Renewed, a multi-year global initiative to unite governments and partners with the clear and compelling goal of effectively ending preventable child deaths.

In 2010, the UN Secretary General launched the Global Strategy for Women's and Children's Health, prompting the commitment of over US$43 billion towards maternal, newborn, and child health.4, 5 Building on this initiative, A Promise Renewed invites governments everywhere to immediately commit to lowering child mortality rates and accelerating progress on newborn, child, and maternal health. UN agencies, industry, civil society, and the many global partnerships and coalitions dedicated to the rights of children pledge to work together to support these government-led efforts and to implement measures that monitor progress, ensure equity, and promote accountability.

The Call to Action and A Promise Renewed will rally efforts to reduce child mortality to below 20 child deaths per 1000 livebirths in every country by 2035. Assuming countries already below 20 continue the historical trends, achieving this target will save an additional 5·6 million children's lives every year by then. It will also promote greater equity through acceleration of efforts where they are needed the most.

Reaching this new goal requires overcoming substantial challenges. Most countries in sub-Saharan Africa would need to increase rates of child mortality reduction to 5—9% per year, which may be two to four times greater than that achieved by many of them in the past decade. But these high rates of mortality reduction are feasible, as shown in the past decade by about 20% of all developing countries and 10% of countries in sub-Saharan Africa.6 An example is Rwanda, which had 6·6% per year mortality reduction from 2000 to 2010.2

In 2010, about 30% (43 of 146) of developing countries already had child mortality rates below 20 child deaths per 1000 livebirths.2 A meaningful target for such countries might be to ensure that all regions—including those that are most vulnerable geographically and socio-economically—achieve the 20 child deaths per 1000 livebirths mortality rate, thus focusing on the reduction of disparities within the countries.6 This would address the issue of inequity, which has represented a key obstacle to progress in the past.

Despite global progress in child survival since 1990, differences in mortality across regions have widened; mortality reduction has tended to be slower in the regions where most child deaths occur. So we see that children in low-income countries are now nearly 18 times more likely to die before the age of 5 years than children in high-income countries (under 5 mortality rate 107 vs 6 per 1000 livebirths), whereas in 1990 they were 14 times more likely to die (164 vs 12 per 1000 livebirths).7

But the wide gap in child mortality between and within countries is a testimony to the unrealised potential in ending preventable child deaths. Achieving the new child survival targets will involve improving the coverage of existing preventive and therapeutic interventions for mothers, newborn babies, and children. The use of new or improved communications and technologies will increase intervention coverage and can add improved efficiency to delivery approaches. UNICEF's recent analysis suggests that by focusing on reaching those groups with the highest under 5 child mortality, such as newborn babies and disadvantaged populations, we can increase the efficiency of interventions to reduce child mortality.8

Investments in other sectors such as education, especially girls' education, will also add to gains.9 Efforts will need to be supported by resources and new or stronger mechanisms for monitoring and accountability at the global and country level. As always, coordinating with and building upon existing initiatives—in this case, the Countdown to 2015, the Commission on Information and Accountability for Women's and Children's Health, and others—is essential to success.

We, as the leaders of WHO and UNICEF, are personally committed to the achievement of MDG 4 and new targets introduced through A Call to Action and A Promise Renewed. The two agencies will work in an even closer collaboration to support countries to achieve universal coverage of effective interventions—and effectively put an end to preventable child deaths.

We declare that we have no conflicts of interest. MC is Director-General of WHO. AL is Executive Director of the United Nations Children's Fund.

1 UN. The Millennium Development Goals report 2009. New York: United Nations Department of Economic and Social Affairs, 2009.

2 UNICEF, WHO, The World Bank, UN Population Division. The Inter-Agency Group for Child Mortality Estimation. Levels and trends in child mortality: 2011 report. New York: UNICEF, 2011. http://www.childinfo.org/files/Child_Mortality_Report_2011.pdf. (accessed May 30, 2012).

3 Liu L, Johnson HL, Cousens S, et alfor the Child Health Epidemiology Reference Group of WHO and UNICEF. Global, regional, and national causes of child mortality: an updated systematic analysis for 2010 with time trends since 2000. Lancet 2012; 379: 2151-2161. Summary | Full Text | PDF(767KB) | CrossRef | PubMed

4 United Nations Secretary-General Ban Ki-moon. Global strategy for women's and children's health. New York: United Nations, 2010. http://www.everywomaneverychild.org/images/content/files/global_strategy/full/20100914_gswch_en.pdf. (accessed May 30, 2012).

5 The Partnership for Maternal, Newborn and Child Health. Analysing commitments to advance the global strategy for women's and children's health. The PMNCH 2011 report. Geneva: PMNCH, 2011. http://www.who.int/pmnch/topics/part_publications/2011_pmnch_report/en/index.html. (accessed May 30, 2012).

6 You D, Wardlaw T. 2012, Modeling required acceleration for child mortality reduction beyond 2015. UNICEF working paper. New York: UNICEF, 2012.

7 You D, Jones G, Hill K, Wardlaw T, Chopra M. Levels and trends in child mortality, 1990—2009. Lancet 2010; 376: 931-933. Full Text | PDF(116KB) | CrossRef | PubMed

8 UNICEF. Narrowing the gaps to meet the goals. New York: UN Children's Fund, 2010. http://www.unicef.org/media/files/Narrowing_the_Gaps_to_Meet_the_Goals_090310_2a.pdf. (accessed May 21, 2012).

9 Gakidou E, Cowling K, Lozano R, Murray CJL. Increased educational attainment and its effect on child mortality in 175 countries between 1970 and 2009: a systematic analysis. Lancet 2010; 376: 959-974. Summary | Full Text | PDF(2855KB) | CrossRef | PubMed

a WHO, Geneva, Switzerland

b UNICEF, New York, NY 10017, USA

Background

The prevention of pneumococcal disease, especially in children in developing countries, is a major international public health priority. Despite all the international attention on the UN's Millennium Development Goal 4—to reduce deaths in children under five years by two-thirds between 1990 and 2015—pneumonia, sepsis, and meningitis together compose more than 25% of the 10 million deaths occurring in children less than five years of age. Streptococcus pneumoniae is a leading bacterial cause of these diseases, and the World Health Organization estimates that approximately 800,000 children die each year of invasive pneumococcal disease.

Pneumococcal conjugate vaccines are currently available and protect against the serotypes that most commonly cause invasive pneumococcal disease in young children in North America and Europe. Such vaccines have been highly successful in reducing the incidence of invasive pneumococcal disease in both vaccinated children and in the non-vaccinated older population by reducing nasopharyngeal carriage (presence of pneumococcal bacteria in the back of the nose) in vaccinated infants, resulting in decreased transmission to contacts—the so-called herd effect. However, few countries with the highest burden of invasive pneumococcal disease, especially those in sub-Saharan Africa, have introduced the vaccine into their national immunization programs.

Why Was This Study Done?

The features of pneumococcal nasopharyngeal carriage and invasive pneumococcal disease in sub-Saharan Africa are different than in other regions. Therefore, careful evaluation of the immune effects of vaccination requires long-term, longitudinal studies. As an alternative to such long-term observational studies, and to anticipate the potential long-term effects of the introduction of pneumococcal conjugate vaccination in sub-Saharan Africa, the researchers conducted a cluster-randomized (by village) trial in The Gambia in which the whole populations of some villages were immunized with the vaccine PCV-7, and other villages received a control.

What Did the Researchers Do and Find?

With full consent from communities, the researchers randomized 21 similar villages in a rural region of western Gambia to receive pneumococcal conjugate vaccine or a control—meningococcal serogroup C conjugated vaccine, which is unlikely to affect pneumococcal carriage rates. For ethical reasons, the researchers only randomized residents aged over 30 months—all young infants received PCV-7, as a similar vaccine had already been shown to be effective in young infants. Before immunization began, the researchers took nasopharyngeal swabs from a random selection of village residents to determine the baseline pneumococcal carriage rates of both the serotypes of pneumococci covered by the vaccine (vaccine types, VTs) and the serotypes of pneumococci not covered in the vaccine (non-vaccine types, NVTs). The researchers then took nasopharyngeal swabs from a random sample of 1,200 of village residents in both groups of villages in cross-sectional surveys at 4–6, 12, and 22 months after vaccination. Villagers and laboratory staff were unaware of which vaccine was which (that is, they were blinded).

Before immunization, the overall prevalence of pneumococcal carriage in both groups was high, at 71.1%, and decreased with age. After vaccination, the overall prevalence of pneumococcal carriage in all three surveys was similar between vaccinated and control villages, showing a marked fall. However, the prevalence of carriage of VT pneumococci was significantly lower in vaccinated than in control villages in all surveys for all age groups. The prevalence of carriage of NVT pneumococci was similar in vaccinated and in control villages, except for a slightly higher prevalence of NVT pneumococci among vaccinated communities in adults at 4–6 months after vaccination. The researchers also found that the overall prevalence of pneumococcal carriage fell markedly after vaccination and reached minimum levels at 12 months in both study arms and in all age groups.

What Do These Findings Mean?

These findings show that vaccination of young Gambian children reduced carriage of VT pneumococci in vaccinated children but also in vaccinated and non-vaccinated older children and adults, revealing a potential herd effect from vaccination of young children. Furthermore, the immunological pressure induced by vaccinating whole communities did not lead to a community-wide increase in carriage of NVT pneumococci during a two-year period after vaccination. The researchers plan to conduct more long-term follow-up studies to determine nasopharyngeal carriage in these communities.

Additional Information

Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001107.

• The World Health Organization has information about pneumococcus
• The US Centers for Disease Control and Prevention provides information about pneumococcal conjugate vaccination

• THE BURDEN OF ARIs IN CRISIS AFFECTED POPULATIONS

Conclusions below; abstract and full text are at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2829474/?tool=pubmed

Conclusions

Our review suggests that the burden of ARI, already very large in stable settings, increases considerably in crises. This pattern appears consistent across different types of crisis, including natural disasters. In the latter, the risk of infectious disease epidemics is usually considered to be low [69], but this may lead to neglect of common conditions such as ARI.

ARIs are less noticeable than epidemic-prone diseases in crises, and any abnormal increases are difficult to detect against a background of consultations for fever and rapidly evolving health facility utilisation rates. This reflects in part a perception by humanitarian workers, mostly based on models of refugee camp health care developed in the 1980s, that infectious disease threats in crises are essentially from easily recognisable and dramatic epidemics of cholera, measles or meningitis Large epidemics of some ARI pathogens may nonetheless occur, and in general ARI pathogens should be considered epidemic-prone in crises, though diagnostics to confirm these epidemics may not be available. The true impact of ARIs is a function of both incidence and case-fatality. There are no acceptable targets for ARI CFR, unlike for cholera or severe malnutrition, making it difficult to monitor the quality of case management on the basis of accepted standards. Further contributing to ARIs' neglect in crisis settings, surveillance systems set up in emergencies generally focus on early detection of visible epidemic-prone diseases. While data on ARIs are often collected, in our experience they are seldom used to inform action.

Our findings of high burden in older children and adults are highly relevant for vaccination strategies, particularly with pneumococcal, Hib, measles and pertussis vaccines. Older children are rarely included in target age groups for these vaccines, but our findings suggest that they perhaps should be, at least in crisis situations.

As advocated for stable settings [70], better characterisation of the epidemiology and aetiology of ARI and particularly pneumonia in crisis-affected settings is critical to rationalise disease priorities, gauge the potential impact of improved diagnostics and treatment, optimise treatment algorithms, and make the best use of available and new vaccines against Hib, pneumococcus, measles and pertussis. Future studies should focus on ALRI; implement clear and standardised case definitions (e.g. clinical versus radiological pneumonia); age-stratify data (with finer strata among children below 5 y so as to better characterise age distribution and optimise vaccine target groups accordingly); and describe the morbidity and mortality burden at the population level rather than based on health-facility data alone. The latter will require focussed community surveillance studies, accompanied by verbal autopsies. Since certain pathogens and serotypes responsible for ARI may be particularly favoured by risk factors such as overcrowding or acute malnutrition, appropriately resourced aetiological studies should also be implemented in a selection of sites.

Addressing ARI in crises is key to achieving global child survival targets and Millennium Development Goals. Accordingly, initiatives such as the WHO and UNICEF-led Global Action Plan for Pneumonia prevention and control (GAPP) need to extend their reach to humanitarian relief settings. Agencies working in crisis settings should invest greater resources in ARI prevention and control, and explicitly consider ARI and pneumonia a top priority across crisis phases and scenarios. Similarly, ARI prevention and treatment should become part of the standard package of minimum public health interventions in crises.