Measles: a disease that has to be eradicated [abstract]

The incidence of measles is on the decline but annually it still claims the lives of one million children worldwide. The devastating effects of the disease on the health and nutrition of children in developing countries and its high mortality are well documented. The rapid decay of maternal antibodies in infants in developing countries results in early susceptibility to the disease and hence the general recommendation to vaccinate at the age of nine months. Sustained international efforts have raised global vaccination coverage rates to about 80 percent, at which level it has remained static. Many countries in the western hemisphere have eliminated the disease by adopting aggressive strategies, which include one-off `catch-up' mass campaigns to vaccinate all children aged 1 to 14 years, `mop-up' campaigns targeting children who were missed during the last `catch-up' campaign, efficient routine vaccination services capable of reaching 90 percent of infants, strong surveillance activities, prompt outbreak response, and `follow-up' campaigns every 2 to 4 years which target 1-4-year-old children. This success story, covered with the fact that measles has many biological features favouring eradication, and considering that it is a severe and lethal disease still prevailing in many areas, calls for immediate international adoption of eradicating goals within a specified period of time. (AU)

The immunisation programme in the Caribbean

In October 1977, the Directing Council of the Pan American Health Organisation (PAHO) approved a resolution concerning the formal inauguration of the Expanded Programme on Immunisation of the Americas. Subsequently, the EPI entered full implementation in those countries that were members of the Caribbean Epidemiology Centre (CAREC) during 1978-80. The establishment of the programme in these countries resulted in focused activities, including training and the development of operational guidelines. The immunisation programmes in the CAREC member countries (CMCs) continues to be very exciting. The eradication of poliomyelitis, the interruption of measles transmission (8 years measles-free), and the implementation of strategies for the elimination of rubella and congenital rubella syndrome (CRS), have presented many challenges to public health practitioners in the region. The success of all these initatives is a reflection of the deep commitment and strong partnerships, which have been developed between the governments, health practitioners, and people of the region (AU)

Jamaica's measles elimination experience

OBJECTIVES: This article describes the effort to eliminate measles from Jamaica and its impact on measles incidence. METHODS: In addition to routine measles vaccination, the Jamaican Ministry of Health implemented a strategy of a 1-time only catch-up vaccination campaign, conducted in 1991, and periodic follow-up campaigns, the first of which occurred in 1995. RESULTS: Since 1991, despite careful surveillance, no serologically confirmed indigenous cases of measles have occurred in Jamaica. CONCLUSIONS: Measles virus circulation has been interrupted in Jamaica. The Jamaican experience provides further evidence that global measles eradicaion is achievable.(AU)

Jamaica's measles elimination experience

OBJECTIVES: This article describes the effort to eliminate measles from Jamaica and its impact on measles incidence. METHODS: In addition to routine measles vaccination, the Jamaican Ministry of Health implemented a strategy of a 1-time-only catch-up vaccination campaign, conducted in 1991, and periodic follow-up campaigns, the first of which occurred in 1995. RESULTS: Since 1991, despite careful surveillance, no serologically confirmed indigenous cases of measles have occurred in Jamaica. The Jamaican experience provides further evidence that global measles eradication is achievable (Au)

Measles elimination in the Americas: evolving strategies

The strategy currently used to control measles in most countries has been to immunize each successive birth cohort through the routine health services delivery system. While measles vaccine coverage has increased markedly, significant measles outbreaks have continued to recur. During the past five years, experience in the Americas suggests that measles transmission has been interrupted in a number of countries (Cuba, Chile, and countries in the English-Speaking Caribbean and successfully controlled in all remaining countries. Since 1991 these countries have implemented one-time "catch-up" vaccination campaigns (conducted during a short period, usually 1 week to 1 month, and targeting all children 9 months through 14 years of age, regardless of previous vaccination status or measles disease history). These campaigns have been followed by improvements in routine vaccination services and in surveillance systems, so that the progress of the measles elimination efforts can be sustained and monitored. Follow-up mass vaccination campaigns for children younger than 5 years are planned to take place every 3 to 5 years (AU)

A structured epidemic model incorporating geographic mobility among regions

A model for the spread of infectious diseases among discrete geographic regions is presented that incorporates a mobility process that describes how contact occurs between individuals from different regions. The general formulation of the mobility process is described, and it is shown that the formulation encapsulates a range of mobility behaviour from complete isolation of all regions (no mobility) to permanent migration between regions. It is then shown how this mobility process fits into an SIR epidemic model, and two examples are given extending its use. The examples include a model for disease transmission in a population with two distinct mobility patterns operating and a model developed to describe a 1984 measles epidemic on the Caribbean island of Dominica(AU)

A structured epidemic model incorporating geographic mobility among regions

A model for the spread of infectious diseases among discrete geographic regions is presented that incorporates a mobility process that describes how contact occurs between individuals from different regions. The general formulation of the mobility process is described, and it is shown that the formulation encapsulates a range of mobility behavior from complete isolation of all regions (no mobility) to permanent migration between regions. It is then shown how this mobility process fits into an SIR epidemic model, and two examples are given extending its use. The examples include a model for disease transmission in a population with two distinct mobility patterns operating and a model developed to describe a 1984 measles epidemic on the Caribbean island of Dominica (AU)

Measles surveillance in the English-speaking Caribbean and Suriname: a key strategy in the campaign to eliminate indigenous measles by 1995 - abstract

In 1988, the Caribbean Health Ministers declared the goal of indigenous measles elimination by 1995 in the light of the success of measles vaccination programmes, introduced in 1982, in decreasing disease occurrence. Prior to 1982, measles occurred continuously in larger territories and Caribbean-wide epidemic activity occurred every 3 to 4 years; the last epidemic being in 1989/90. One of the key strategies for measles elimination was a mass immunization campaign conducted in May - June 1991 with a 91.4 per cent vaccination uptake rate among the target population aged 9 months - 15 years. Nine countries achieved coverage rates of > 95 per cent. This was followed by the introduction of an active and sensitive surveillance system on 1st September, 1991 and up to October 31, 1992, 504 suspected cases of measles were reported. However, there were only two (2) confirmed cases (from Barbados - one indiginous and one imported) and 124 compatible cases. Thus, in the 14 months since the launch of the new surveillance system, one case of indigenous measles has been indentified. Logically, the combination of widespread epidemic activity in 1989/90, followed by a very successful mass vaccination campaign in 1991, has enormous potential for breaking all chains of transmission in a population. Continued high-quality surveillance will be necessary to certify elimination but transmission appears to have been interrupted throughout the English-speaking Caribbean. If this is possible in the Caribbean, across a wide variety of territories, then global eradication is one step closer to being a reality (AU)

Diagnosis of measles by clinical case definition in dengue-endemic areas: implications for measles surveillance and control

In many countries measles surveillance relies heavily on the use of a standard clinical case definition; however, the clinical signs ans symptoms of measles are similiar to those of dengue. For example, during 1985, in Puerto Rico, 22 (23 percent) of 94 cases of illness with rashes that met measles clinical case definition were serologically confirmed as measles, but 32 (34 percent) others were serologically confirmed as dengue (AU)

Geographic spread of measles on the island of Dominica, West Indies

Because of the short incubation period of most acute infectious diseases, short-term and daily mobility are more important than permanent and seasonal migration for the spread of these diseases. Yet most studies of population mobility focus on permanent or semipermanent change of residence. Here, we describe the results from a field study conducted on the island of Dominica, West Indies, during the summers of 1989 and 1990 and the winter of 1991. The study was designed to collect data on short-term mobility rather than migration. These mobility data are linked with data on pattern of measles transmission during a 1984 epidemic. Three-hundred five individuals from all parts of the island were interviewed about their daily travel patterns, their travel off the island, and the travel of members of their immediate family. In addition to these respondents, interviews were conducted with representatives of most of the major occupations that involve travel in the course of a workday. Data were also collected on the number and type of motor vehicles traveling along various routes on the island and on travel of native residents to the capital city, Roseau, to buy or sell at the major weekly market. Analysis of the interviews shows that travel within the island is clearly nonrandom. For example, almost everyone interviewed traveled to Roseau at least once a month, but 40 percent of the respondents had never been to any of the major villages in the Grand Bay Health District, which is only about a half-hour from Roseau. Patterns of disease transmission have been directly affected by these mobility patterns. The measles epidemic in 1984 apparently did not reach the Grand Bay Health District, even though all other areas of the island experienced significant rates of infection. Analysis of reasons for the relative isolation of the Grand Bay Health District indicates the importance of transportation patterns, as well as social, cultural, and geographic factors, to the disease transmission patterns throughout the island. (AU)

Summary report on the ninth meeting of Caribbean EPI managers, held in the Department of Guadeloupe, France November 9-13, 1992

Besides the various topics that will be discussed in the subsequent sections of this report, it is important to state from the onset the tremendous progress made by every country towards the organization and implementation of surveillance system for detection of suspected measles cases. In one year, the countries of the English-speaking Caribbean and Suriname went from a phase in which little active surveillance was occuring to what now may be one of the most sophisticated systems in the world (AU)

Expanded programme on immunization: a parish-level evaluation of the surveillance system

To achieve the goal of measles elimination in the Caribbean subregion by 1995, a 3-part strategy has been developed. This plan of action consists of: strengthening the ongoing Expanded Programme on Immunization (EPI) in each country; mass immunization campaigns to stop transmission; and improved and expanded surveillance systems to identify and respond to suspected cases. Poliomyelitis eradication also requires heightened surveillance. In the case of poliomyelitis this surveillance seeks to identify and investigate all cases of acute flacid paralysis. As poliomyelitis eradication in the Americas nears, and measles elimination moves beyond the stage of mass immunization campaigns, the improvement of surveillance systems is becoming a central priority for the Caribbean (AU)

Fever with rash illness surveillance English-speaking Caribbean & Surinam 1991-1992

The English-speaking Caribbean and Suriname have targeted measles for elimination by the end of 1995, One of the main strategies is to have in place an active and sensitive system of surveillance at regional and national levels so that all suspected cases of measles can be detected, investigated and analysed, and appropriate control measures implemented to stop transmission (AU)

Coverage survey, an evaluation of the immunization programme for infants - abstract

The objective of this study was to obtain information on the coverage rate for DPT, poliomyelitis and MMR/measles and rubella among children in Curacao. A cluster sampling technique was used to select 211 children, aged 15 to 26 months, whose immunization status was evaluated. Data were obtained from the immunization card and by interviewing the parent. The coverage rate ranged from 99.1 percent (first DPT) to 70.6 percent(MMR); 67.8 percent of children were fully immunized. Two children (0.9 percent were not immunized at all. Less than 10 percent of all immunization doses was administered outside the Well Baby Clinics. Some of the recorded doses were given too early (invalid)according to the WHO criteria. Accurate registration was recommended as a possible way to decrease the number of invalid doses. It was found that many of the 3 doses of poliomyelitis vaccine were administered too late and it is recommended that the 3rd oral polio dose should be given earlier. Reasons why children were not fully immunized could be divided into: obstacles to participation in the programme (55.9 percent), lack of motivation (10.3 percent) and lack of information (33.8 percent). Illness of the child was the main obstacle (AU)

Epidemiological indicators and epidemiology of measles in the English-speaking Caribbean and Suriname

The main purpose of this article is to discuss the definitions and limitations of the indicators used to study the epidemiology of measles in the English-speaking Caribbean and Suriname. In addition, the epidemiology of measles over the past ten years is briefly reviewed, with a focus on recent epidemics. The predicted epidemioogical picture of measles over the next few years is also discussed and, finally, the difference between elimination and eradiction of measles is explained. (AU)