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Objective: To develop a model for identifying areas at high risk for sporadic measles outbreaks based on an analysis of factors associated with a national outbreak in South Africa between 2009 and 2011., Methods: Data on cases occurring before and during the national outbreak were obtained from the South African measles surveillance programme, and data on measles immunization and population size, from the District Health Information System. A Bayesian hierarchical Poisson model was used to investigate the association between the risk of measles in infants in a district and first-dose vaccination coverage, population density, background prevalence of human immunodeficiency virus (HIV) infection and expected failure of seroconversion. Model projections were used to identify emerging high-risk areas in 2012., Findings: A clear spatial pattern of high-risk areas was noted, with many interconnected (i.e. neighbouring) areas. An increased risk of measles outbreak was significantly associated with both the preceding build-up of a susceptible population and population density. The risk was also elevated when more than 20% of infants in a populous area had missed a first vaccine dose. The model was able to identify areas at high risk of experiencing a measles outbreak in 2012 and where additional preventive measures could be undertaken., Conclusion: The South African measles outbreak was associated with the build-up of a susceptible population (owing to poor vaccine coverage), high prevalence of HIV infection and high population density. The predictive model developed could be applied to other settings susceptible to sporadic outbreaks of measles and other vaccine-preventable diseases.

Elimination of endemic measles transmission is the culmination of a range of control measures at a national level. Current documentation of elimination proposed by WHO's regional offices requires achieving specific targets for surveillance process indicators. We demonstrate how Australia, although not meeting these specific targets, has satisfied multiple criteria that justify the formal declaration of measles elimination. Our review shows that few countries previously declaring measles elimination have satisfied the current WHO surveillance targets. We argue that the requirements for recognition of measles elimination should not restrict countries to a particular type of surveillance system or surveillance criteria.

Objective: To assess the progress made towards meeting the goals of the African Regional Strategic Plan of the Expanded Programme on Immunization between 2001 and 2005., Methods: We reviewed data from national infant immunization programmes in the 46 countries of WHOs African Region, reviewed the literature and analysed existing data sources. We carried out face-to-face and telephone interviews with relevant staff members at regional and subregional levels., Findings: The African Region fell short of the target for 80% of countries to achieve at least 80% immunization coverage by 2005. However, diphtheria-tetanus-pertussis-3 coverage increased by 15%, from 54% in 2000 to 69% in 2004. As a result, we estimate that the number of nonimmunized children declined from 1.4 million in 2002 to 900,000 in 2004. In 2004, four of seven countries with endemic or re-established wild polio virus had coverage of 50% or less, and some neighbouring countries at high risk of importation did not meet the 80% vaccination target. Reported measles cases dropped from 520,000 in 2000 to 316,000 in 2005, and mortality was reduced by approximately 60% when compared to 1999 baseline levels. A network of measles and yellow fever laboratories had been established in 29 countries by July 2005., Conclusion: Rates of immunization coverage are improving dramatically in the WHO African Region. The huge increases in spending on immunization and the related improvements in programme performance are linked predominantly to increases in donor funding.

The Americas have set a goal of interrupting indigenous transmission of measles using a strategy developed by the Pan American Health Organization (PAHO). This strategy includes recommendations for vaccination activities to achieve and sustain high immunity in the population and is complemented by sensitive epidemiological surveillance systems developed to monitor illnesses characterized by febrile rash, and to provide effective virological and serological surveillance. A key component in ensuring the success of the programme has been a laboratory network comprising 22 national laboratories including reference centres. Commercially available indirect enzyme immunoassay kits (EIA) for immunoglobulin M (IgM)-class antibodies are currently being used throughout the region. However, because there are few or no true measles cases in the region, the positive predictive value of these diagnostic tests has decreased. False-positive results of IgM tests can also occur as a result of testing suspected measles cases with exanthemata caused by Parvovirus B19, rubella and Human herpesvirus 6, among others. In addition, as countries maintain high levels of vaccination activity and increased surveillance of rash and fever, the notification of febrile rash illness in recently vaccinated people can be anticipated. Thus, managers in the measles elimination programme must be prepared to address the interpretation of a positive result of a laboratory test for measles IgM when clinical and epidemiological data may indicate that the case is not measles. The interpretation of an IgM-positive test under different circumstances and the definition of a vaccine-related rash illness in a setting of greatly reduced, or absent, transmission of measles is discussed.

Measles is one of the most infectious diseases. Before measles vaccine was introduced, nearly everyone contracted the disease at some point in childhood. By the late 1980s, most countries had incorporated measles vaccine into their routine immunization programmes. Globally, about 800 000 children nevertheless still die from measles annually, half of them in Africa. Eradicating measles would therefore play an important role in improving children's survival. The 24th Pan American Sanitary Conference in 1994 established a goal of eradicating measles from the Americas. Progress to date has been remarkable and the disease is no longer endemic in the Americas, with most countries having documented interruption of transmission. As of November 2003, 12 months had elapsed since the last indigenous case was detected in Venezuela. This experience shows that measles transmission can be interrupted, and that this can be sustained over a long period of time. Global eradication is feasible if an appropriate strategy is implemented. Even under a new paradigm in which immunization is not discontinued after measles is eradicated, eradication will be a good investment to avoid expensive epidemics and save the lives of almost one million children annually. A world free of measles by 2015 is not a dream.

The study reports incidences of measles in Catalonia, Spain, as detected by surveillance, and analyses the specific characteristics of the outbreaks reported for the period 1986-95. Incidences per 100,000 inhabitants were calculated for the period 1971-95. The following variables were studied: year of presentation, number of cases, median age, transmission setting, cases with a record of vaccination and preventable cases. Associations between variables were determined using odds ratios (OR). The incidence of measles declined from 306.3 cases in 1971 to 30.9 in 1995. A total of 50 outbreaks were investigated. The outbreaks that occurred in the last two years of the study had a higher likelihood of having a transmission setting other than primary school (OR = 3.9); a median case age > 10 years (OR = 7.2); and fewer than 6 cases (OR = 2.3). The characteristics of recent outbreaks, marked by a rise both in transmission outside the primary-school setting and in median age, indicate the need for the introduction of a specific vaccination programme at the end of adolescence in addition to control of school-related outbreaks.

As a result of the highly contagious nature of measles before the onset of rash, nosocomial transmission will remain a threat until the disease is eradicated. However, a number of strategies can minimize its nosocomial spread. It is therefore vital to maximize awareness among health care staff that an individual with measles can enter a health facility at any time and that a continual risk of the nosocomial transmission of measles exists. The present review makes two groups of recommendations: those which are generally applicable to all countries, and certain additional recommendations which may be suitable only for industrialized countries.

A serological survey was conducted among Tuareg nomads to determine their level of immunity to measles. More than half (57.9%) of the children under 10 years of age did not have detectable antibodies to measles, suggesting that transmission of the disease is low in this mobile population. Mothers' reports of their children's history of measles were accurate (positive predictive value 93.9% for under-5-year-olds). Nomads are a reservoir of susceptible individuals who require immunization strategies adapted to their particular life-styles. These can be implemented at relatively low cost.