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Background: In 2008 all WHO member states endorsed a target of 90% reduction in measles mortality by 2010 over 2000 levels. We developed a model to estimate progress made towards this goal., Methods: We constructed a state-space model with population and immunisation coverage estimates and reported surveillance data to estimate annual national measles cases, distributed across age classes. We estimated deaths by applying age-specific and country-specific case-fatality ratios to estimated cases in each age-country class., Findings: Estimated global measles mortality decreased 74% from 535,300 deaths (95% CI 347,200-976,400) in 2000 to 139,300 (71,200-447,800) in 2010. Measles mortality was reduced by more than three-quarters in all WHO regions except the WHO southeast Asia region. India accounted for 47% of estimated measles mortality in 2010, and the WHO African region accounted for 36%., Interpretation: Despite rapid progress in measles control from 2000 to 2007, delayed implementation of accelerated disease control in India and continued outbreaks in Africa stalled momentum towards the 2010 global measles mortality reduction goal. Intensified control measures and renewed political and financial commitment are needed to achieve mortality reduction targets and lay the foundation for future global eradication of measles., Funding: US Centers for Disease Control and Prevention (PMS 5U66/IP000161)., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Modelling is valuable in the planning and evaluation of interventions, especially when a controlled trial is ethically or logistically impossible. Models are often used to calculate the expected course of events in the absence of more formal assessments. They are also used to derive estimates of rare or future events from recorded intermediate points. When developing models, decisions are needed about the appropriate level of complexity to be represented and about model structure and assumptions. The degree of rigor in model development and assessment can vary greatly, and there is a danger that existing beliefs inappropriately influence judgments about model assumptions and results., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Measles persists in Europe despite the incorporation of the measles vaccine into routine childhood vaccination programmes more than 20 years ago. Our aim was therefore to review the epidemiology of measles in relation to the goal of elimination by 2010., Methods: National surveillance institutions from 32 European countries submitted data for 2006-07. Data for age-group, diagnosis confirmation, vaccination, hospital treatment, the presence of acute encephalitis as a complication of disease, and death were obtained. 30 countries also supplied data about importation of disease. Clinical, laboratory-confirmed, and epidemiologically linked cases that met the requirements for national surveillance were analysed. Cases were separated by age: younger than 1 year, 1-4 years, 5-9 years, 10-14 years, 15-19 years, and older than 20 years. Countries with indigenous measles incidence per 100 000 inhabitants per year of 0, less than 0.1, 0.1-1, and more than 1 were grouped into categories of zero, low, moderate, and high incidence, respectively., Findings: For the 2 years of the study, 12 132 cases of measles were recorded with most cases (n=10 329; 85%) from five countries: Romania, Germany, UK, Switzerland, and Italy. Most cases were unvaccinated or incompletely vaccinated children; however, almost a fifth were aged 20 years or older. For the same 2 years, seven measles-related deaths were recorded. High measles incidence in some European countries revealed suboptimum vaccination coverage. Of the 210 cases that were reported as being imported, 117 (56%) came from another country within Europe and 43 (20%) from Asia., Interpretation: The suboptimum vaccination coverage raises serious doubts that the goal of elimination by 2010 can be attained. Achievement and maintenance of optimum vaccination coverage and improved surveillance are the cornerstones of the measles elimination plan for Europe.

Background: In 2002, the UN General Assembly Special Session on Children adopted a goal to reduce deaths owing to measles by half by the end of 2005, compared with 1999 estimates. We describe efforts and progress made towards this goal., Methods: We assessed trends in immunisation against measles on the basis of national implementation of the WHO/UNICEF comprehensive strategy for measles mortality reduction, and the provision of a second opportunity for measles immunisation. We used a natural history model to evaluate trends in mortality due to measles., Results: Between 1999 and 2005, according to our model mortality owing to measles was reduced by 60%, from an estimated 873,000 deaths (uncertainty bounds 634,000-1,140,000) in 1999 to 345,000 deaths (247,000-458,000) in 2005. The largest percentage reduction in estimated measles mortality during this period was in the western Pacific region (81%), followed by Africa (75%) and the eastern Mediterranean region (62%). Africa achieved the largest total reduction, contributing 72% of the global reduction in measles mortality. Nearly 7.5 million deaths from measles were prevented through immunisation between 1999 and 2005, with supplemental immunisation activities and improved routine immunisation accounting for 2.3 million of these prevented deaths., Interpretation: The achievement of the 2005 global measles mortality reduction goal is evidence of what can be accomplished for child survival in countries with high childhood mortality when safe, cost-effective, and affordable interventions are backed by country-level political commitment and an effective international partnership.

Public health interventions aimed at children in Mexico have placed the country among the seven countries on track to achieve the goal of child mortality reduction by 2015. We analysed census data, mortality registries, the nominal registry of children, national nutrition surveys, and explored temporal association and biological plausibility to explain the reduction of child, infant, and neonatal mortality rates. During the past 25 years, child mortality rates declined from 64 to 23 per 1000 livebirths. A dramatic decline in diarrhoea mortality rates was recorded. Polio, diphtheria, and measles were eliminated. Nutritional status of children improved significantly for wasting, stunting, and underweight. A selection of highly cost-effective interventions bridging clinics and homes, what we called the diagonal approach, were central to this progress. Although a causal link to the reduction of child mortality was not possible to establish, we saw evidence of temporal association and biological plausibility to the high level of coverage of public health interventions, as well as significant association to the investments in women education, social protection, water, and sanitation. Leadership and continuity of public health policies, along with investments on institutions and human resources strengthening, were also among the reasons for these achievements.

Background: The Bedouin Arab population of southern Israel is in transition from a semi-nomadic lifestyle to permanent settlement, with many characteristics of a third-world population. A major outbreak of measles in the winter of 1990-91, with an incidence of 415.6 per 100,000 and a case fatality rate of 2.2 % among the Bedouin, led to the establishment of a national committee, which recommended an intervention programme. We report on the effect of the programme implementation on the reduction of vaccine-preventable communicable diseases in a Bedouin Arab population., Methods: We compared immunisation coverage and incidence of reportable vaccine-preventable communicable diseases before and after implementation of the intervention programme., Findings: Implementation of the intervention programme was associated with a marked increase in immunisation coverage, from 53% for first measles immunisation among those born in 1988, and reaching 2 years of age in 1990 at the start of the outbreak, to 90% at age 2 years among those born in 2001. We noted a decrease in all vaccine-preventable communicable diseases, except for pertussis, during this period., Interpretation: The implementation of a targeted programme to improve immunisation coverage, and other concomitant changes in health-care delivery, was temporally associated with reduction of vaccine-preventable communicable diseases in a population of Bedouin Arabs in Israel who are living in semi-nomadic conditions. The success of the programme could be applicable to semi-nomadic populations living in other areas of the middle east.

Background: Females given high-titre measles vaccine (HTMV) have high mortality; diphtheria-tetanus-pertussis (DTP) vaccination might be associated with increased female mortality. We aimed to assess whether DTP or inactivated poliovirus (IPV) administered after HTMV was associated with increased female-male mortality ratio., Methods: In three trials from West Africa, 2000 children were randomised to HTMV or control vaccine at 4-5 months of age; a second vaccination was given at age 9-10 months (standard measles vaccine). Children in high-titre groups were given IPV or DTP-IPV. Another 944 children received HTMV as routine vaccination in Senegal., Findings: When we compared high-titre and control groups, no difference in mortality between the first and the second vaccination was noted. After the second vaccination, the female-male mortality ratio was 1.84 (95% CI 1.19-2.84) in children in the high-titre groups who received DTP-IPV or IPV, and 0.59 (0.34-1.04) in controls who received standard measles vaccine (p=0.007). Children who received HTMV but no additional DTP-IPV or IPV had a female-male mortality ratio of 0.83 (0.41-1.67). This ratio was 2.22 (1.04-4.71) for children who received DTP-IPV after routine HTMV and 1.00 (0.68-1.47) for those who did not. When we combined the results from all trials, the female-male mortality ratio was 1.93 (1.33-2.81) for those who received DTP or IPV after HTMV, and 0.96 (0.69-1.34) for those who did not (p=0.006)., Interpretation: A change in sequence of vaccinations, rather than HTMV itself, may have been the cause of increased female mortality in these trials.

Measles is the most frequent cause of vaccine-preventable childhood deaths. Infants younger than the recommended age for vaccination are susceptible to the disease, and in developing countries they have a high risk of complications and mortality. Vaccine coverage in excess of 95% interrupts endemic transmission of measles in many countries, but achievement of such coverage almost always requires coordinated supplementary mass vaccination campaigns. There are substantial health gains if countries improve measles vaccine coverage, irrespective of whether or not high coverage is achieved; these gains include much lower measles complication and case fatality rates, long-term interepidemic duration, and possibly non-specific improvements in survival of children. Investigation into the cost-effectiveness of different strategies for measles control, including mass campaigns, two-dose schedules, and young-infant doses, would help countries to formulate control policies appropriate to their setting. Pneumonia is the most common fatal complication associated with measles, and at least 50% of measles-related pneumonias are due to bacterial superinfection. WHO has developed standard case management programmes for measles, but there are several unresolved clinical issues, including optimum indications for antibiotic treatment, the importance of intravenous immunoglobulin, the role of viral coinfection, and the risk of tuberculosis after measles. The priority in worldwide efforts to control measles is to lend support to poor countries, helping them to increase vaccine coverage and sustain improvements to vaccination infrastructure, and to address technical issues with respect to optimum vaccination schedules. Measles represents a specific challenge, whereby partnerships between high-income and developing nations would reduce child mortality in developing countries; such partnerships are not without incentive for high-income countries, since without them imported measles cannot be prevented.

We have previously reported that vitamin A supplementation with measles vaccine at age 9 months increases measles-specific antibody concentrations in children at age 18 months compared with placebo. We examined these children when they reached age 6-8 years. Fewer vitamin A-supplemented children had non-protective antibody concentrations (p=0.0095); among children with protective antibody levels, vitamin A-supplemented children tended to have higher geometric mean antibody titres (p=0.09). Thus, simultaneous administration of vitamin A and measles vaccine at age 9 months had a long-term effect on measles-specific antibody levels and may contribute to improved measles control in less-developed countries.

Background: In 1994, ministers of health of countries of North and South America established the goal of measles eradication from the western hemisphere by 2000. To accomplish this goal, the Pan American Health Organization (PAHO) developed an enhanced measles vaccination strategy., Methods: PAHO's measles eradication vaccination strategy has evolved into three principal components; a catch-up measles vaccination campaign, maintenance of high vaccination coverage (keep-up), and periodic follow-up measles vaccination campaigns. To monitor progress towards measles eradication, measles surveillance has been strengthened, including the laboratory investigation of suspected measles cases., Findings: Both the catch-up and follow-up mass campaigns achieved high vaccination coverages in the respective targeted age groups. In 1996, only 2109 confirmed measles cases were reported in the Americas. In 1997, there was a resurgence of measles in the Americas, mostly as a result of a large measles outbreak with over 42000 cases, which occurred mainly among unvaccinated young adults in Sao Paulo State, Brazil. By 1998, there was a reduction in the number of reported confirmed measles cases, with a total of 14474 cases. Reduction of cases continued to the end of 1999, with a total of only 2828 confirmed cases., Interpretation: PAHO's measles eradication strategy has been effective in interrupting transmission and maintaining the absence of measles virus circulation in most parts of the Americas. The PAHO experience provides strong evidence that with full implementation of an appropriate vaccination strategy, measles transmission can be effectively interrupted.

Previous studies of measles mortality in West Africa have shown a significantly higher case-fatality rate (CFR) among girls than among boys. This study aimed to find out whether the male/female difference in CFR is related to different risks for boys and girls of being infected as secondary rather than index cases and of transmission from someone of the same or the opposite sex. The study was conducted in Niakhar, a rural area of Senegal (population 24,000). All cases of measles reported between March, 1983, and December, 1986, were investigated to determine source of infection and pattern of transmission. For each case, the closest source of infection was judged the most likely. Death was attributed to measles if it occurred within 6 weeks of the onset of rash. Girls had a higher measles CFR than boys (53 deaths/722 cases [7.3%] vs 45/778 [5.8%]); the relative risk of death was 1.30 (95% confidence interval [CI] 0.89-1.90). Secondary cases infected by a child of the opposite sex had a 2.44 (1.48-4.02) times higher risk of death than did secondary cases infected by a child of the same sex. The risk of cross-sex transmission of infection was significantly greater for female than for male secondary cases (1.26 [1.09-1.47]). When this difference in risk of exposure to infection from the opposite sex was taken into account, the difference in risk of death between girls and boys disappeared (1.06 [0.66-1.69]). Within families, the CFR was higher in huts with 1 boy and 1 girl affected than in huts of either 2 boys or 2 girls affected (relative risk 2.16 [0.99-4.70]). Measles infection contracted from a person of the opposite sex is more severe. Variation in exposure may be an important determinant of sex differences in case fatality.

The use of Edmonston-Zagreb high-titre (EZ-HT) vaccine at age 6 months has been recommended for countries in which measles before the age of 9 months is a substantial cause of death, but little is known about the long-term effects of high-titre live measles vaccines given early in life. In a randomised vaccine trial in a rural area of Senegal, children were randomly assigned at birth to three vaccine groups: EZ-HT at 5 months (n = 336); Schwarz high-titre (SW-HT) at 5 months (n = 321); and placebo at 5 months followed by standard low-titre Schwarz vaccine at 10 months (standard: n = 358). All children were prospectively followed for 24-39 months in a well-established demographic surveillance system. Child mortality after immunisation was significantly higher in the two groups which received high-titre vaccines than in the group given the standard vaccine. The relative risk of death was 1.80 (95% confidence interval [CI] 1.18-2.74; p = 0.007) in the EZ-HT group and 1.51 (0.97-2.34; p = 0.07) in the SW-HT group compared with the standard group. The three vaccine groups were comparable as regards various social, family, and health characteristics, and there was no difference in mortality between children who received the standard vaccine and those who were eligible for the trial but did not take part for various reasons. The higher risk of death in the two high-titre vaccine groups remained significant in multivariate analyses. These findings suggest a need to reconsider the use of high-titre measles vaccines early in life in less developed countries.

In a zone with a high measles case-fatality rate the risk of dying between the ages of 7 and 35 months for a vaccinated population was compared with that for an unvaccinated control-group. Life-table analysis for both groups showed that measles vaccination reduced the risk of dying at the age of maximum exposure to measles. The gain in survival probability, however, tended to diminish afterwards, to approach that of the unvaccinated group.

The establishment of a mortality committee as an educational exercise in a general hospital in rural Kenya was found to have widespread implications. Its findings led to an expansion of the community health services based on the hospital. Within the hospital it resulted in extensive alterations in routine procedures, plant, equipment, and a redeployment of staff.