Showing papers on "Measles published in 2011"

How the case against the MMR vaccine was fixed

Abstract: In the first part of a special BMJ series, Brian Deer exposes the bogus data behind claims that launched a worldwide scare over the measles, mumps, and rubella vaccine, and reveals how the appearance of a link with autism was manufactured at a London medical school

Global distribution of measles genotypes and measles molecular epidemiology.

Abstract: A critical component of laboratory surveillance for measles is the genetic characterization of circulating wild-type viruses. The World Health Organization (WHO) Measles and Rubella Laboratory Network (LabNet), provides for standardized testing in 183 countries and supports genetic characterization of currently circulating strains of measles viruses. The goal of this report is to describe the lessons learned from nearly 20 years of virologic surveillance for measles, to describe the global databases for measles sequences, and to provide regional updates about measles genotypes detected by recent surveillance activities. Virologic surveillance for measles is now well established in all of the WHO regions, and most countries have conducted at least some baseline surveillance. The WHO Global Genotype Database contains >7000 genotype reports, and the Measles Nucleotide Surveillance (MeaNS) contains >4000 entries. This sequence information has proven to be extremely useful for tracking global transmission patterns and for documenting the interruption of transmission in some countries. The future challenges will be to develop quality control programs for molecular methods and to continue to expand virologic surveillance activities in all regions.

Health Care–Associated Measles Outbreak in the United States After an Importation: Challenges and Economic Impact

Abstract: (See the editorial commentary by Ostroff, on pages 1507–9.)Background. On 12 February 2008, an infected Swiss traveler visited hospital A in Tucson, Arizona, and initiated a predominantly health care–associated measles outbreak involving 14 cases. We investigated risk factors that might have contributed to health care–associated transmission and assessed outbreak-associated hospital costs.Methods. Epidemiologic data were obtained by case interviews and review of medical records. Health care personnel (HCP) immunization records were reviewed to identify non–measles-immune HCP. Outbreak-associated costs were estimated from 2 hospitals.Results. Of 14 patients with confirmed cases, 7 (50%) were aged ≥18 years, 4 (29%) were hospitalized, 7 (50%) acquired measles in health care settings, and all (100%) were unvaccinated or had unknown vaccination status. Of the 11 patients (79%) who had accessed health care services while infectious, 1 (9%) was masked and isolated promptly after rash onset. HCP measles immunity data from 2 hospitals confirmed that 1776 (25%) of 7195 HCP lacked evidence of measles immunity. Among these HCPs, 139 (9%) of 1583 tested seronegative for measles immunoglobulin G, including 1 person who acquired measles. The 2 hospitals spent US$799,136 responding to and containing 7 cases in these facilities.Conclusions. Suspecting measles as a diagnosis, instituting immediate airborne isolation, and ensuring rapidly retrievable measles immunity records for HCPs are paramount in preventing health care–associated spread and in minimizing hospital outbreak–response costs.

Who Gets Measles in Europe

Abstract: Background Measles outbreaks continue to occur in Europe as a result of suboptimum vaccination coverage. This article aims to describe individuals susceptible to measles, and provide an overview of affected groups and the public settings in which measles transmission occurred in Europe in 2005-2009. Methods Individuals susceptible to measles were described and categorized on the basis of factors leading to nonvaccination and vaccine failure. A literature search was conducted to identify affected groups and public settings in which measles transmission occurred. Results Most individuals susceptible to measles are previously uninfected and unvaccinated. The reasons for nonvaccination in individuals eligible for vaccination ranged from lack of information to poor access to health care. Several outbreaks have emerged in Roma and Sinti, Traveller, anthroposophic, and ultra-orthodox Jewish communities, and immigrants identifying them as being particularly at risk. Public settings for transmission included mostly educational and health care facilities. Conclusions Improved efforts are needed to strengthen immunization programs, identify barriers for measles-containing vaccine uptake, and explore methods to target vulnerable populations that are not being reached with routine immunization delivery services. Specific measures are needed to prevent and control measles in educational and health care facilities. Failure to identify who gets measles and implement the elimination strategies raises concerns for the successful and sustainable elimination of measles in Europe.

Field Effectiveness of Live Attenuated Measles-Containing Vaccines: A Review of Published Literature

Abstract: Background Information on measles vaccine effectiveness (VE) is critical to help inform policies for future global measles control goals. Methods We reviewed results of VE studies published during 1960-2010. Results Seventy papers with 135 VE point estimates were identified. For a single dose of vaccine administered at 9-11 months of age and ≥12 months, the median VE was 77.0% (interquartile range [IQR], 62%-91%) and 92.0% (IQR, 86%-96%), respectively. When analysis was restricted to include only point estimates for which vaccination history was verified and cases were laboratory confirmed, the median VE was 84.0% (IQR, 72.0%-95.0%) and 92.5% (IQR, 84.8%-97.0%) when vaccine was received at 9-11 and ≥12 months, respectively. Published VE vary by World Health Organization region, with generally lower estimates in countries belonging to the African and SouthEast Asian Regions. For 2 doses of measles-containing vaccine, compared with no vaccination, the median VE was 94.1% (IQR, 88.3%-98.3%). Conclusions The VE of the first dose of measles-containing vaccine administered at 9-11 months was lower than what would be expected from serologic evaluations but was higher than expected when administered at ≥12 months. The median VE increased in a subset of articles in which classification bias was reduced through verified vaccination history and laboratory confirmation. In general, 2 doses of measles-containing vaccine provided excellent protection against measles.

Two Case Studies of Modified Measles in Vaccinated Physicians Exposed to Primary Measles Cases: High Risk of Infection But Low Risk of Transmission

Abstract: In 2009, measles outbreaks in Pennsylvania and Virginia resulted in the exposure and apparent infection of 2 physicians, both of whom had a documented history of vaccination with >2 doses of measles-mumps-rubella vaccine. These physicians were suspected of having been infected with measles after treating patients who subsequently received a diagnosis of measles. The clinical presentation was nonclassical in regard to progression, duration, and severity. It is hypothesized that the 2 physicians mounted vigorous secondary immune responses typified by high avidity measles immunoglobulin G antibody and remarkably high neutralizing titers in response to intense and prolonged exposure to a primary measles case patient. Both of the physicians continued to see patients, because neither considered that they could have measles. Despite surveillance for cases among contacts, including unvaccinated persons, no additional cases were identified.

Laboratory Characterization of Measles Virus Infection in Previously Vaccinated and Unvaccinated Individuals

Abstract: Waning immunity or secondary vaccine failure (SVF) has been anticipated by some as a challenge to global measles elimination efforts. Although such cases are infrequent, measles virus (MeV) infection can occur in vaccinated individuals following intense and/or prolonged exposure to an infected individual and may present as a modified illness that is unrecognizable as measles outside of the context of a measles outbreak. The immunoglobulin M response in previously vaccinated individuals may be nominal or fleeting, and viral replication may be limited. As global elimination proceeds, additional methods for confirming modified measles cases may be needed to understand whether SVF cases contribute to continued measles virus (MeV) transmission. In this report, we describe clinical symptoms and laboratory results for unvaccinated individuals with acute measles and individuals with SVF identified during MeV outbreaks. SVF cases were characterized by the serological parameters of high-avidity antibodies and distinctively high levels of neutralizing antibody. These parameters may represent useful biomarkers for classification of SVF cases that previously could not be confirmed as such using routine laboratory diagnostic techniques.

Progress Toward Control of Rubella and Prevention of Congenital Rubella Syndrome—Worldwide, 2009

Abstract: Rubella, usually a mild rash illness in children and adults, can cause serious consequences when a pregnant woman is infected, particularly in early pregnancy. These serious consequences include miscarriage, fetal death or an infant born with birth defects (i.e., congenital rubella syndrome (CRS)). The primary purpose for rubella vaccination is the prevention of congenital rubella infection including CRS. Since 1969, several rubella virus vaccines have been licensed for use; however, until the 1990s, use of rubella-containing vaccine (RCV) was limited primarily to developed countries. In 1996, it was estimated that 110,000 infants with CRS were born annually in developing countries. In 2000, the first World Health Organization rubella vaccine position paper was published to guide introduction of RCV in national childhood immunization schedules. From 1996 to 2009, the number of countries that introduced RCV into their national routine childhood immunization programs increased by 57% from 83 countries in 1996 to 130 countries in 2009. In addition, three of the six WHO regions established rubella control and CRS prevention goals: Region of the Americas and Europe rubella elimination by 2010 and 2015, respectively, and Western Pacific Region-accelerated rubella control and CRS prevention by 2015. Also, during this time period, the number of rubella cases reported decreased from 670,894 in 2000 to 121,344 in 2009. Rubella control and prevention of CRS can be accelerated by integrating with current global measles mortality reduction and regional elimination activities.

Measles among healthcare workers: a potential for nosocomial outbreaks.

Abstract: We report here 14 cases of measles among healthcare workers (HCWs) in Public Hospitals of Marseilles, France that occurred between April and November 2010. All cases but one were under 30 years of age. Following the identification of these cases, we checked the immune status among 154 HCWs who volunteered to take part in the study and showed that 93% and 88% were immune against measles and mumps respectively. HCWs non-immunised against measles were all under 30 years of age.

A World Without Measles

Abstract: Measles is one of the most highly transmissible contagious human diseases. In the prevaccine era, .90% of children had measles by their 15th birthday. In 1980, before the use of measles vaccine was widespread, an estimated 2.6 million deaths due to measles occurred worldwide. The aim of Millennium Development Goal 4 (MDG4) is to reduce the overall number of deaths among children by two-thirds by 2015, compared with the level in 1990.[1] Recognizing the potential of measles vaccination to reduce mortality among children and that measles vaccination coverage may be considered a marker of access to children’s health services, routine measles vaccination coverage was selected as an indicator of progress towards this goal. At the 63rd World Health Assembly (WHA) in 2010, Member States endorsed the following accelerated measles control targets to be achieved by 2015 [2]: exceed 90% coverage with the first dose of measlescontaining vaccine nationally and exceed 80% vaccination coverage in every district; reduce annual measles incidence to ,5 cases per million and maintain that level; and reduce measles mortality by $95%, compared with 2000 estimates. These ambitious targets are aligned with MDG4 and represent milestones towards the global eradication of measles. Global mortality attributed to measles has decreased by an impressive 78% from an estimated 733,000 deaths in 2000 to 164,000 in 2008 [3]. The decrease in measles mortality has accounted for 23% of the overall decrease in childhood mortality since 1990 and for 24% since 2000.[4] All countries, with the exception of India, achieved the 2010 global goal of reducing measles mortality by 90% two years ahead of the target date [3]. This progress has been made possible through accelerated measles control activities implemented by high-burden countries with the financial and technical support of the Measles Initiative. (Launched in 2001, the Measles Initiative is an international partnership committed to reducing measles deaths worldwide, founded and led by the American Red Cross, the Centers for Disease Control and Prevention, UNICEF, United Nations Foundation, and the World Health Organization (WHO) and joined subsequently by a number of other organizations. Additional information available at http://www.measlesinitiative.org). Moreover, measles elimination has been sustained in the WHO Region of the Americas since 2002, and important steps are being taken to achieve the goal of measles elimination in 3 other WHO regions (Europe, Eastern Mediterranean, and Western Pacific) by 2015 or before. In 2009, the African Region adopted the goal of eliminating measles by 2020, and the South East Asian Region passed a resolution urging countries to mobilize resources to support elimination of measles with discussions continuing about establishing a target date. In May 2008, encouraged by the progress being made in reducing measles deaths worldwide, Member States requested that the WHO evaluate the feasibility of the global eradication of measles [5]. A comprehensive program of work was performed that explored the biological, programmatic, economic, social, and political aspects of the feasibility of measles eradication. In July 2010, at a Global Consultation on the Feasibility of Measles Eradication, the results of these studies were presented to an ad hoc advisory panel [6]. The panel concluded that measles can and should be eradicated and that global eradication by 2020 is feasible given evidence of measurable progress towards the 2015 targets (see the advisory group report in this issue). Furthermore, the ad hoc advisory panel stressed that measles eradication activities should be carried out in the context of strengthening Potential conflicts of interest: none reported. Supplement sponsorship: This article is part of a supplement entitled ''Global Progress Toward Measles Eradication and Prevention of Rubella and Congenital Rubella Syndrome'', which was sponsoredby theCenters forDiseaseControl andPrevention. Two of the authors are staff members of the World Health Organization. The authors alone are responsible for the views expressed in this publication, and they do not necessarily represent the decisions, policy, or views of the World Health Organization. Correspondence: Peter Strebel, MBChB, MPH, Accelerated Disease Control, Expanded Programme on Immunization, Dept of Immunization, Vaccines and Biologicals, World Health Organization, Avenue Appia, CH-1211, Geneva 27, Switzerland (strebelp@who.int). The Journal of Infectious Diseases 2011;204:S1–S3 The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals. permissions@oup.com 0022-1899 (print)/1537-6613 (online)/2011/204S1-0001$14.00 DOI: 10.1093/infdis/jir111

Biological Feasibility of Measles Eradication

Abstract: Recent progress in reducing global measles mortality has renewed interest in measles eradication. Three biological criteria are deemed important for disease eradication: (1) humans are the sole pathogen reservoir; (2) accurate diagnostic tests exist; and (3) an effective, practical intervention is available at reasonable cost. Interruption of transmission in large geographical areas for prolonged periods further supports the feasibility of eradication. Measles is thought by many experts to meet these criteria: no nonhuman reservoir is known to exist, accurate diagnostic tests are available, and attenuated measles vaccines are effective and immunogenic. Measles has been eliminated in large geographical areas, including the Americas. Measles eradication is biologically feasible. The challenges for measles eradication will be logistical, political, and financial.

Global Eradication of Measles: An Epidemiologic and Economic Evaluation

Abstract: Background. Measles remains an important cause of morbidity and mortality in children in developing countries. Due to the success of the measles mortality reduction and elimination efforts thus far, the WHO has raised the question of whether global eradication of measles is economically feasible. Methods. The cost-effectiveness of various measles mortality reduction and eradication scenarios was evaluated vis-a `-vis the current mortality reduction goal in six countries and globally. Data collection on costs of measles vaccination were conducted in six countries in four regions: Bangladesh, Brazil, Colombia, Ethiopia, Tajikistan, and Uganda. The number of measles cases and deaths were projected from 2010 to 2050 using a dynamic, age-structured compartmental model. The incremental cost-effectiveness ratios were then calculated for each scenario vis a vis the baseline. Results. Measles eradication by 2020 was the found to be the most cost-effective scenario, both in the six countries and globally. Eradicating measles by 2020 is projected to cost an additional discounted $7.8 billion and avert a discounted 346 million DALYs between 2010 and 2050. Conclusions. In conclusion, the study found that, compared to the baseline, reaching measles eradication by 2020 would be the most cost-effective measles mortality reduction scenario, both for the six countries and on a global basis.

Successful respiratory immunization with dry powder live-attenuated measles virus vaccine in rhesus macaques

Abstract: Measles remains an important cause of childhood mortality worldwide. Sustained high vaccination coverage is the key to preventing measles deaths. Because measles vaccine is delivered by injection, hurdles to high coverage include the need for trained medical personnel and a cold chain, waste of vaccine in multidose vials and risks associated with needle use and disposal. Respiratory vaccine delivery could lower these barriers and facilitate sustained high coverage. We developed a novel single unit dose, dry powder live-attenuated measles vaccine (MVDP) for respiratory delivery without reconstitution. We tested the immunogenicity and protective efficacy in rhesus macaques of one dose of MVDP delivered either with a mask or directly intranasal with two dry powder inhalers, PuffHaler and BD Solovent. MVDP induced robust measles virus (MeV)-specific humoral and T-cell responses, without adverse effects, which completely protected the macaques from infection with wild-type MeV more than one year later. Respiratory delivery of MVDP was safe and effective and could aid in measles control.

Elimination of Rubella and Congenital Rubella Syndrome in the Americas

Abstract: In 2003, the Pan American Health Organization (PAHO) adopted a resolution calling for rubella and congenital rubella syndrome (CRS) elimination in the Americas by the year 2010. To accomplish this goal, PAHO advanced a rubella and CRS elimination strategy including introduction of rubella-containing vaccines into routine vaccination programs accompanied by high immunization coverage, interruption of rubella transmission through mass vaccination of adolescents and adults, and strengthened surveillance for rubella and CRS. The rubella elimination strategies were aligned with the successful measles elimination strategies. By the end of 2009, all countries routinely vaccinated children against rubella, an estimated 450 million people had been vaccinated against measles and rubella in supplementary immunization activities, and rubella transmission had been interrupted. This article describes how the region eliminated rubella and CRS.

Impact of changing the measles vaccine vial size on Niger's vaccine supply chain: a computational model

Abstract: Background Many countries, such as Niger, are considering changing their vaccine vial size presentation and may want to evaluate the subsequent impact on their supply chains, the series of steps required to get vaccines from their manufacturers to patients. The measles vaccine is particularly important in Niger, a country prone to measles outbreaks.

Spread of measles virus D4-Hamburg, Europe, 2008-2011.

Abstract: A new strain of measles virus, D4-Hamburg, was imported from London to Hamburg in December 2008 and subsequently spread to Bulgaria, where an outbreak of >24,300 cases was observed. We analyzed spread of the virus to demonstrate the importance of addressing hard-to-reach communities within the World Health Organization European Region regarding access to medical care and vaccination campaigns. The D4-Hamburg strain appeared during 2009–2011 in Poland, Ireland, Northern Ireland, Austria, Greece, Romania, Turkey, Macedonia, Serbia, Switzerland, and Belgium and was repeatedly reimported to Germany. The strain was present in Europe for >27 months and led to >25,000 cases in 12 countries. Spread of the virus was prevalently but not exclusively associated with travel by persons in the Roma ethnic group; because this travel extends beyond the borders of any European country, measures to prevent the spread of measles should be implemented by the region as a whole.

Changing epidemiology of measles in Africa.

Abstract: Background. In Africa before the introduction of measles vaccination, measles primarily affected young children. To describe measles epidemiology in Africa since the start of accelerated measles control activities in 2001, we analyzed regional measles case-based surveillance data for 2002–2009.Methods. Country-years were grouped by 10-year moving average of routine measles vaccination coverage (aMCV1). Age was log transformed, and pair-wise comparisons of means were made. A χ 2 test was used to assess association between coverage and age groups. Cumulative percent curves and percentiles of age, dot plots with Loess curve, and Spearman rank correlation coefficient were calculated.Results. Of 180,284 suspected cases, 73,009 (41%) were confirmed as measles. Of these, the mean age was 79 months (median, 36 months; interquartile range, 16–96 months) and significantly younger in country-years with <50% aMCV1 than those with 50%–74% aMCV1 (P = .03) and ≥75% (P = .02). With increasing coverage, there was a slight decrease in age in the 10th and 25th and moderate increase in age in the 50th, 75th, and 90th percentiles.Conclusions. During 2002–2009, the median age of confirmed measles was 36 months. In countries with ≥50% aMCV1 coverage compared with low-coverage countries, age shifted to older children and young adults; for infants, age decreased slightly with higher coverage.

An assessment of mumps vaccine effectiveness by dose during an outbreak in Canada

Abstract: Background This investigation was done to assess vaccine effectiveness of one and two doses of the measles, mumps and rubella (MMR) vaccine during an outbreak of mumps in Ontario. The level of coverage required to reach herd immunity and interrupt community transmission of mumps was also estimated. Methods Information on confirmed cases of mumps was retrieved from Ontario’s integrated Public Health Information System. Cases that occurred between Sept. 1, 2009, and June 10, 2010, were included. Selected health units supplied coverage data from the Ontario Immunization Record Information System. Vaccine effectiveness by dose was calculated using the screening method. The basic reproductive number ( R 0 ) represents the average number of new infections per case in a fully susceptile population, and R 0 values of between 4 and 10 were considered for varying levels of vaccine effectiveness. Results A total of 134 confirmed cases of mumps were identified. Information on receipt of MMR vaccine was available for 114 (85.1%) cases, of whom 63 (55.3%) reported having received only one dose of vaccine; 32 (28.1%) reported having received two doses. Vaccine effectiveness of one dose of the MMR vaccine ranged from 49.2% to 81.6%, whereas vaccine effectiveness of two doses ranged from 66.3% to 88.0%. If we assume vaccine effectiveness of 85% for two doses of the vaccine, vaccine coverage of 88.2% and 98.0% would be needed to interrupt community transmission of mumps if the corresponding reproductive values were four and six. Interpretation Our estimates of vaccine effectiveness of one and two doses of mumps-containing vaccine were consistent with the estimates that have been reported in other outbreaks. Outbreaks occurring in Ontario and elsewhere serve as a warning against complacency over vaccination programs.

Progress toward measles elimination in the People's Republic of China, 2000-2009.

Abstract: In 2006, China set a goal of measles elimination by 2012. To describe progress toward this goal, we reviewed relevant policies and strategies and analyzed national data for 2000-2009. In response to implementation of these strategies, including increased routine measles vaccination coverage and province-specific supplementary immunization activities (SIAs), reported measles incidence decreased to a historically low level of 39.5 cases per million in 2009. A synchronized nationwide SIA was scheduled in 2010 to further decrease susceptibility to measles. However, reaching and maintaining measles elimination will require strong political commitment and efforts for strengthening surveillance, increasing 2-dose vaccine coverage to >95%, stricter enforcement of the requirement to check immunization status at school entry, and careful attention to measles susceptibility in those aged ≥15 years.

Human papillomavirus vaccination and social inequality: results from a prospective cohort study.

Abstract: We investigated the effect of social inequalities on the uptake of human papillomavirus (HPV) vaccination, combining data from a feasibility study conducted in 2007-2008 in 2817 secondary schoolgirls in two UK primary-care trusts, with census and child health records. Uptake was significantly lower in more deprived areas (P<0·001) and in ethnic minority girls (P=0·013). The relatively small proportion of parents who actively refused vaccination by returning a negative consent form were more likely to come from more advantaged areas (P<0·001). Non-responding parents were from more deprived (P<0·001) and ethnic minority (P=0·001) backgrounds. Girls who did not receive HPV vaccination were less likely to have received all their childhood immunizations particularly measles, mumps and rubella (MMR). Different approaches may be needed to maximize HPV vaccine uptake in engaged and non-responding parents, including ethnic-specific approaches for non-responders.

Measles Mortality Reduction Contributes Substantially to Reduction of All Cause Mortality Among Children Less Than Five Years of Age, 1990–2008

Abstract: Background. The Millennium Development Goal 4 (MDG4) to reduce mortality in children aged 12 million in 1990 to 10.6 million in 2001 (13% reduction) and to 8.8 million in 2008 (28% reduction). Measles accounted for about 7% of deaths in this age group in 1990 and 1% in 2008, equal to 23% of the global reduction in all-cause mortality in this age group from 1990 to 2008. Conclusions. Aggressive efforts to prevent measles have led to this remarkable reduction in measles deaths. The current funding gap and insufficient political commitment for measles control jeopardizes these achievements and presents a substantial risk to achieving MDG4. Language: en

An evaluation of respiratory administration of measles vaccine for prevention of acute lower respiratory infections in children

Abstract: Background Measles was responsible for an estimated 100,000 deaths worldwide in 2008. Despite being a vaccine-preventable disease, measles remains a major cause of morbidity and mortality in young children. Although a safe and effective injectable measles vaccine has been available for over 50 years it has not been possible to achieve the uniformly high levels of coverage (required to achieve measles eradication) in most parts of the developing world. Aerosolised measles vaccines are now under development with the hope of challenging the delivery factors currently limiting the coverage of the existing vaccine.

Improving Global Virologic Surveillance for Measles and Rubella

Abstract: An important aspect of laboratory surveillance for measles and rubella is the genetic characterization of circulating wild-type viruses to support molecular epidemiologic studies and to track transmission pathways. Virologic surveillance that is sufficient to document the interruption of transmission of measles and rubella viruses will be an essential criterion for verification of elimination. Laboratories in the World Health Organization (WHO) Measles and Rubella Laboratory Network have worked to improve and expand virologic surveillance as many regions move toward elimination of measles and rubella/congenital rubella syndrome. As countries approach elimination, it will be necessary to obtain genetic information from as many chains of transmission as possible. In addition, baseline virologic surveillance, especially for rubella, needs to be improved in many countries. This report contains a summary of recent improvements to the methods used for virologic surveillance.

Measles vaccination in HIV-infected children: systematic review and meta-analysis of safety and immunogenicity.

Abstract: Background. Measles control may be more challenging in regions with a high prevalence of HIV infection. HIV-infected children are likely to derive particular benefit from measles vaccines because of an increased risk of severe illness. However, HIV infection can impair vaccine effectiveness and may increase the risk of serious adverse events after receipt of live vaccines. We conducted a systematic review to assess the safety and immunogenicity of measles vaccine in HIV-infected children. Methods. The authors searched 8 databases through 12 February 2009 and reference lists. Study selection and data extraction were conducted in duplicate. Meta-analysis was conducted when appropriate. Results. Thirty-nine studies published from 1987 through 2008 were included. In 19 studies with information about measles vaccine safety, more than half reported no serious adverse events. Among HIV-infected children, 59% (95% confidence intervals [CI], 46–71%) were seropositive after receiving standard-titer measles vaccine at 6 months (1 study), comparable to the proportion of seropositive HIV-infected children vaccinated at 9 (8 studies) and 12 months (10 studies). Among HIV-exposed but uninfected and HIV-unexposed children, the proportion of seropositive children increased with increasing age at vaccination. Fewer HIV-infected children were protected after vaccination at 12 months than HIV-exposed but uninfected children (relative risk, 0.61; 95% CI, .50–.73). Conclusions. Measles vaccines appear to be safe in HIV-infected children, but the evidence is limited. When the burden of measles is high, measles vaccination at 6 months of age is likely to benefit children of HIV-infected women, regardless of the child's HIV infection status.