Evaluation of the Bahamas' MMR campaign.

PIP: During July-December 1997, Bahamas conducted its first mass measles, mumps, and rubella (MMR) campaign targeting people aged 4-40 years living on 19 islands. 68% of the Bahamas' population reside on New Providence and Grand Bahama. The campaign was implemented to keep the country free of measles, interrupt rubella virus transmission, and prevent further cases of congenital rubella syndrome (CRS), by eliminating susceptible populations for rubella and mumps infection. No cases of measles and rubella have been reported since the campaign, despite the fact that the island receives more than 1 million tourists annually. in July 1998, the Ministry of Health of the Bahamas asked PAHO/SVI to evaluate the MMR campaign. A summary is presented of the evaluation report, with regard to the measles and rubella situation, safe syringe practices, vaccination coverage, the surveillance of adverse reactions, and vaccination during pregnancies.^ieng

Update: measles in the Americas.

PIP: For the first 6 weeks of 1999, 114 confirmed measles cases have been reported from Argentina, Bolivia, Chile, Colombia, Dominican Republic, Uruguay, and the US. Dominican Republic had reported 34% of all cases up to February 13. Although this outbreak was first detected in December 1998, the first cases seem to have occurred early in November 1998. The outbreak is currently being investigated to identify possible sources of infection. Preliminary findings are that most of the 39 confirmed cases occurred among nonvaccinated individuals eligible for vaccination. Measles vaccination efforts have been slow in Bolivia's Cochabamba department. All countries in the region need to monitor the build-up of susceptibles as a result of either low vaccination coverage in routine programs or an inadequate coverage in follow-up campaigns. A sensitive surveillance system must also be maintained and cases aggressively investigated. These measures should prevent the re-establishment of measles virus circulation in the region.^ieng

Good surveillance is key to measles eradication.

PIP: The Pan American Health Organization's recommended strategy for measles eradication is for countries to "catch-up" on mass vaccination, to "keep-up" by maintaining better than 95% coverage in every district, and to "follow-up" on with rapid investigation of suspected measles cases. This latter effort will allow health workers to determine if a case resulted from importation or indigenous transmission and to determine the chain of transmission if more than one case occurs. In turn, this determination will allow officials to make necessary changes to avoid future cases of program failure. Recent surveillance efforts in Uruguay enabled identification of 23 cases of measles in four chains of transmission, three of which involved a health worker as transmitter or receptor of the infection.^ieng

Bolivia: all out fight against measles!

PIP: Since May of 1998 Bolivia has been affected by a measles outbreak, which began in the municipality of Yacuiba, within the department of Tarija. Bolivia reported 1004 confirmed measles cases in 1998, and during the first 40 weeks of 1999 there have been 1218 confirmed cases. About 51% of the total measles cases for 1999 in the Region have been reported in Bolivia. In response to this situation, the Ministry of Health of Bolivia has prepared a special plan of action and issued a Ministerial Resolution on October 26, aimed at ending the outbreak and interrupting virus transmission. The objective is to vaccinate at least 95% of all children between the ages of 6 months and 4 years (1,071,723 children) in a National Measles Vaccination Campaign, to be held between 28 November and 17 December in each municipality. This decision of the Ministry of Health indicates the high-level commitment of national authorities to the health of the population, and it is an excellent example of Panamericanism in action. (full text).^ieng

Paraguay and Brazil discuss joint strategies for the eradication of measles.

PIP: The measles epidemic which began at the end of 1996 in Brazil and lasted through 1997, with more than 26,000 confirmed cases, affected several countries in Latin America, including Paraguay. There have been 205 confirmed measles cases in the border area between Brazil and Paraguay, which has a population of approximately 1.5 million people. On the basis of a number of problems identified in the border municipalities of both countries, it was decided to set up 3 local border committees for surveillance, information sharing, and measles eradication planning purposes. A technical meeting held February 12-13, 1998, in Curitiba, Brazil, to establish immediate strategies for controlling measles outbreaks in the border municipalities between Paraguay and Brazil resulted in the preparation of a project for technical cooperation between countries (TCC). TCC projects are a key component of the Pan American Health Organization's (PAHO) technical cooperation because they foster collaboration among countries in the region to solve certain health problems. Representatives from the Ministries of Health of Brazil and Paraguay, as well as regional and municipal officials, members of the Brazilian Cooperation Agency in the Ministry of Foreign Affairs, the Ministry of Health of Argentina, and PAHO country staff in Paraguay and Brazil attended the meeting.^ieng

Districts at risk for measles in El Salvador.

PIP: Following the reintroduction of measles virus in Central America through an outbreak in Costa Rica in 1997, El Salvador's Ministry of Health, in October 1997, reviewed the vaccination coverage levels of children under 1 year of age in all of its 262 districts to determine which districts had not achieved coverage levels of at least 90%. The ministry subsequently organized a mop-up measles vaccination campaign for November-December 1997 in the 84 districts identified as being at high risk, targeting children under age 5 years. House-to-house vaccination was conducted, using the current routine vaccination schedule. Including first doses and boosters, 36,560 doses of measles vaccines and 8637 doses of MMR were administered. 91,115 children under 1 year old live in the districts. 69,552 houses were visited, of which 52,494 were found occupied, and 41,597 children under age 5 years were identified in the households. This mop-up vaccination campaign against measles reduced from 84 to 61 the number of districts at risk for measles. Recommendations are presented.^ieng

Follow-up measles campaign in the Dominican Republic.

PIP: The Dominican Republic conducted a national follow-up measles vaccination campaign 6 weeks after sustaining heavy damage from Hurricane Georges, on November 6-12, targeting 830,517 children aged 9 months to 5 years in 29 provinces and the capital city. This campaign was the first mass vaccination effort in the country, following the beginning of the decentralized delivery of health services. Priority was given to vaccinating against diphtheria, whooping cough, and tetanus, especially in refugee camps. More than 500,000 vaccines were given to different age groups, with almost 100,000 of those immunized under 5 years old. Children aged 9 months to 5 years were targeted for immunization regardless of their vaccination status. At the same time, children aged 2 months through 2 years were immunized against poliomyelitis. Vaccination activities were continued until the entire target population was reached and no important side effects have thus far been reported. The government of Mexico donated 300,000 doses of measles vaccine, while other vaccines for the campaign were acquired through the PAHO Revolving Fund for Vaccine Procurement. The decentralized implementation of this campaign allowed the population to actively participate and the resulting high vaccination coverage rates.^ieng

Andean region: measles on the way out.

PIP: In August 1996, health officials, program managers, epidemiologists, laboratory representatives, UNICEF, Rotary International, and Pan American Health Organization staff attended the VII Andean EPI Meeting in Quito, Ecuador, to review the progress of the Expanded Program on Immunization (EPI). All Andean countries have conducted catch-up measles vaccination campaigns targeting children 9 months to 15 years old. These campaigns achieved 90% vaccine coverage and a strong reduction in measles incidence (only 7 confirmed cases in 1996). Follow-up campaigns were conducted during 1995-1996 in Colombia, Peru, and Chile. They were expected in Bolivia, Ecuador, Peru, and Venezuela during 1997-1999. The Andean countries implemented a national surveillance system for measles in 1995. Meeting representatives made eight recommendations regarding measles. For example, health officials should reach and maintain routine vaccination coverage greater than 95% for children 12-23 months old in each municipality. Laboratory representatives proposed recommendations on uniform criteria for measles diagnosis. The last indigenous wild poliovirus in the Americas was isolated in 1991. Imported wild poliovirus remains a concern. The Andean countries are expanding surveillance of neonatal tetanus activities. Since 1989 the frequency of neonatal tetanus has been falling in the Andean region, especially in Bolivia and Peru. The impact of migration on the control of neonatal tetanus should be a higher priority. Participants repeated the need for systematic use and continuous monitoring of EPI indicators (e.g., vaccination coverage). Three countries plan on analyzing surveys on missed opportunities for vaccination in 1996. Three countries presented progress reports on hepatitis B vaccination and surveillance. Participants issued recommendations on quality control of vaccines. The responsibility for quality control lies with the manufacturers and the government. Vaccines for invasive diseases (e.g., Haemophilus influenzae type b) may be included in national EPI programs.^ieng

Decrease of measles cases in Mexico.

PIP: During November 27-December 5, 1995, in 21 states of Mexico, staff of PAHO's Special Program for Vaccines and Immunization and specialists from member countries interviewed personnel responsible for measles surveillance and reviewed thousands of daily patient records to evaluate Mexico's measles surveillance system. The personnel were well informed about case definitions and procedures. The team found only one case that fit the measles case definition. This case had not been reported to the surveillance system. Yet epidemiologists investigated 1206 suspected measles cases. The surveillance system could not identify chains of transmission for many of the suspected measles cases, suggesting that these cases were false positives or linked to undetected importations. The process for identifying and reporting cases of suspected measles was inefficient. Specifically, there were different case investigation forms for epidemiologists than for laboratories. The forms were long and requested too much clinical information, most of which was left blank. Patients often had to go through many medical consultation/examinations to make sure that they met the clinical case definition and to obtain a specimen for laboratory testing. There was no system at the local level for tracking suspected cases or once-investigated-now-discarded cases. The different levels of the health system had different databases. Ongoing training and feedback were rare. The Ministry of Health's (MOH) surveillance system did not communicate with that of other systems, e.g., Mexican Institute of Social Security. No ongoing evaluation or monitoring of the surveillance system took place. Based on the findings, the evaluation team made eight recommendations. The system should develop indicators for the quality of the surveillance system. Another identified need was integration of other institutions into MOH's surveillance system by standardizing surveillance training and sharing a common database of measles cases.^ieng

Progress of EPI programs reviewed in Central American and Andean regions.

PIP: Measles eradication was a priority agenda item of the two annual meetings of the managers of the Expanded Program on Immunization (EPI) in the Andean and Central American regions which took place in August 1995. In order to reduce the risk of new outbreaks, Central American countries are planning measles vaccination campaigns for children under age five years before March 1996. Tabulated data show that overall coverage rates for EPI antigens remained at high rates in the region for 1994-95. During the meetings, minimum measles surveillance indicators were recommended and countries were advised to maintain over 95% vaccination coverage of all children under a year old, to monitor the accumulation of susceptibles and carry out vaccination campaigns when this number is equal to the cohort of newborns, to increase the recommended age for primary measles vaccination from 9 to 12 months, to expand the reporting network, to strengthen use of the Measles Elimination Surveillance System database, and to focus epidemiological surveillance on suspected measles cases. Recommendations to bolster the decline in neonatal tetanus (NNT) in the region include making vaccination a priority for women of childbearing age in high-risk areas, identifying new high-risk areas, and investigating all cases of NNT. During the meetings, participants emphasized the importance of maintaining the eradication of poliomyelitis through political commitment, surveillance activities, vaccination coverage, and timely notification. Recommendations to control diphtheria included standardizing case definitions and control measures, strengthening surveillance, promoting the use of dT vaccine in women of childbearing age at high risk of NNT, organizing a national laboratory network for diagnosis, and strengthening the vaccination of one-year-old children with DPT. Vaccination against hepatitis B has already begun in high-risk areas of some countries and is being incorporated in the vaccination programs of others. The systematic use and monitoring of the following EPI indicators were also recommended: vaccination coverage, surveillance, number and percentage of municipalities with DPT1 coverage over 90%, dropout rates between DPT1/DPT3 and DPT1/measles, percentages of resources in the EPI Plan of Action directed toward high-risk areas, proportion of national resources in relation to external resources, and degree of interagency coordination.^ieng

Intradermal administration of measles vaccines.

The aim of the study reported here was to determine if bifurcated needles or multiple puncture cylinders would prove suitable for administration of measles vaccines. Children 9 to 11 months old in São Paulo, Brazil, were assigned to receive either Biken-Cam 70 (5,000 TCID50/0.5 ml) or Edmonston-Zagreb (7,000 TCID50/0.5 ml) measles vaccines intradermally with a bifurcated needle or a multiple puncture cylinder. These devices are usually used to administer smallpox or BCG vaccine. The volume of vaccine inoculated was approximately 0.003 ml. Measles IgG antibodies were measured by enzyme-linked immunosorbent assay (ELISA) at the time of vaccination and 8 weeks later. The study participants were examined 14 days after inoculation for possible adverse reactions. Overall, the children's average age was 9.5 +/- 0.66 months at vaccination. None of the 45 recipients of Biken-Cam vaccine responded serologically. The 49 Edmonston-Zagreb vaccine recipients immunized with the multiple puncture cylinder had a somewhat higher serologic response rate (35%) and mean concentration of measles antibodies (323 mIU/ml) than those 51 who received the same vaccine administered with the bifurcated needle (26% and 291 mIU/ml, respectively). The rates of reported symptoms after vaccination did not differ significantly among the groups. Overall, the low serologic response rates following intradermal immunization with for devices tested in this study indicate that this route of administration is not suitable for routine administration of standard-titer vaccines.

Chile averts measles outbreak.

PIP: Chile is the first mainland country in Latin America to have arrested epidemic transmission of measles virus for more than 18 months. The health ministry successfully averted an imminent outbreak of the measles virus. Health personnel knew that the 2- to 3-year epidemic periodicity of measles meant that an outbreak could be expected in 1992. Although coverage levels had hovered around 90% since the last epidemic, an outbreak could occur among those who had not been vaccinated in that period or those who failed to seroconvert. To prevent an outbreak, health authorities decided to organize a National Campaign that would vaccinate 95% of all children aged 9 months to 14 years old (3,930,000 children) in 2 weeks. 99.6% of the children were immunized with a standard dose, regardless of their previous vaccination history. Post-campaign epidemiologic surveillance of rash and fever illness was carried out from April 17, 1992 with the organization of laboratory diagnostic capabilities. Compliance with the probable measles case definition nearly doubled between 1992 and 1993, and the proportion of probable measles cases for which blood samples were taken increased from 64% to 79% for the same period. Compatible cases declined from 8% to 5% between 1992 and 1993. From the time the campaign was organized to the end of 1993, only 2 imported cases of measles were confirmed. Chile's experience offers several useful hints for other countries, particularly setting up a system for the active surveillance of rash and fever illness. The measles surveillance case definition must be disseminated and the critical clinical information for each case must be reported. Priority should also be given to ensuring that adequate blood samples are taken before a case is discarded. The final diagnosis for a large percentage of probable cases was determined by laboratory analysis. Surveillance means vaccinating all susceptibles as soon as a probable case is reported.^ieng

Jamaica puts muscle into measles immunization.

PIP: The Jamaican Ministry of Health (MOH) has prioritized increasing coverage of children with measles vaccine. Despite the effects of a fairly large epidemic in 1990, many parents fail to recognize the danger posed by measles. Thus, only 63% of children under 1 year old were vaccinated in 1992, whereas 77% were vaccinated in 1991. A health education campaign to increase coverage is being carried out in the mass media and among community groups. Immunization against measles in Jamaica, is also hindered by the cost of the vaccine and by problems in ensuring a constant supply. The MOH is attempting to deal with these problems by placing bulk orders that can be supplied and paid for in increments and by exploring ways of lowering the overall cost through a bidding process. The MOH also faces difficulties because 20% of Jamaica's health care professionals leave the country for better jobs each year.^ieng

Jamaican measles surveillance system.

PIP: In 1991, the Ministry of Health and technical consultants from PAHO evaluated the measles surveillance system in Jamaica. This system consisted of the notification system, the sentinel sites system, active hospital surveillance, laboratory reporting, and special surveys. The team concentrated their efforts on the system's ability to detect and investigate suspected cases of measles. The team visited sentinel sites including health centers, hospitals, or a physician in all 13 parishes. 44 sites operated at the time. It spoke with medical Officers and Senior Public Health Nurses and evaluated written records. The notification system had recently classified measles as a Class I disease to encourage a rapid public health response and to secure investigation records. The major weakness of the notification system was case investigation. In 1991, health workers investigated only 6 (3%) of 208 suspected cases within 48 hours and eventually investigated only 76 (36.5%). 23 cases were confirmed as measles. Serology tests revealed that most suspected cases were actually rubella. This indicated a need to include serological testing for confirmation. The team found that the notification system underreported cases. Each sentinel site was required to collect each week a count of the number of cases of measles and other conditions to monitor trends. 87% reported the counts weekly. The sites consistently reported measles bas ed on clinical suspicion. Public health staff visited hospitals weekly to review cases of target disease including measles. They visited at least 1 hospital regularly in each parish. Hospital records did not contain consistent measles data. For example, only 10 of 13 visit reports included patient's name, age, sex, and address and only 7 included outcome. Detailed information was only available on 13 of the 208 suspected cases so the team was only able to evaluate them.^ieng