The epidemiology of measles in Tianjin,China, 2005–2014

BackgroundMeasles incidence in China has declined over the last decade and elimination is targeted by 2020. Despite increases in routine immunization services and supplementary immunization activities (SIAs), periodic outbreaks continue to occur. In this paper, we examine measles epidemiology during 2005–2014 in Tianjin, China.MethodsMeasles case data were extracted from a web-based communicable disease surveillance system. We examined the socio-demographic characteristics of measles case patients, including age, sex, urbanicity, residency status, and vaccination history. Demographic characteristics of cases were compared with the general population.ResultsFrom January 1, 2005 to December 31, 2014, 12,466 measles cases in Tianjin were reported. Among the cases, 7179 (57.6%) were male and 5287 (42.4%) were female. Over time, more cases occurred in adults, and for the 2711 cases in 2014, the majority were either infants <1 year (558, 20.58%) or adults ≥20 years (2043, 75.36%). Municipal-wide SIAs in Tianjin occurred in 2008 and 2010 with reduction in measles cases the following year for both (189 cases in 2009, and 37 cases in 2011). The number of cases rebounded to pre-SIA levels or higher within 1–3 years following each SIA: 1990 cases in 2010 and 2711 cases in 2014. Vaccination status was reported as “none” or “unknown” for 84% of all reported measles cases.ConclusionsDespite the general decline in cases, measles outbreaks continue to occur. Although the SIAs reduce numbers in their immediate aftermath, case counts rebound 1–3 years after the intervention. Continued monitoring of cases through disease surveillance activities accompanied by targeted immunization activities, including to adults, can help ensure progress toward elimination.     

Epidemiology of a workplace measles outbreak dominated by modified measles cases at Kansai international airport,Japan, during august–september 2016

ObjectivesIn August 2016, a measles outbreak at Kansai International Airport was the first workplace measles outbreak since Japan was verified as having achieved measles-elimination status in March 2015. We investigated this outbreak with a focus on evaluating the ability of vaccinated individuals to transmit measles virus (MV).MethodsWe considered a case of laboratory-confirmed measles with onset between August 9 and September 29, 2016, among workers of Kansai International Airport. History of vaccination status with measles-containing vaccine (MCV) was confirmed by reviewing records. The potential sources of each MV infection were assessed by interviewing each infected worker about the clinical course of their infection and their behavioral history.ResultsOf 30 affected ground crews identified, 16 (53%) were vaccinated with ≥ 1 dose of MCV, 2 (7%) were unvaccinated, and 12 (40%) had an unknown vaccination status. The index case, a patient with classical measles with unknown vaccination status, presumably transmitted MV to all the subsequent 29 cases. The majority of patients (23, 77%; 15 vaccinated, 8 in unknown vaccination status) were diagnosed with modified measles due to mild illness. Modified measles were characterized clinically by signs of catarrh (4/23, 17%) in a few cases, with a median incubation period of 16 (range, 11–21) days. No onward transmission from vaccinated cases was suggested. An overseas traveler who visited the airport with measles symptoms was identified as the possible primary source of this outbreak.ConclusionsThe low MV transmission ability of vaccinated individuals was reaffirmed. Contact tracing of vaccinated modified measles cases can be limited to a person at high risk of infection (e.g., households, person with immunosuppression). To maintain measles-elimination status, completing two doses of MCV should be ensured, especially for international travelers and for those who are frequently exposed to these travelers, such as airport workers.     

Can measles be eradicated globally?

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.     

Measles,the media,and MMR: Impact of the 2014–15 measles outbreak

ObjectiveIn late 2014, a measles outbreak beginning in California received significant media attention. To better understand the impact of this outbreak, we conducted a survey to assess and compare among vaccine hesitant and non-hesitant new mothers how this outbreak affected vaccine knowledge, attitudes, vaccination plans, and media use.MethodsA cross-sectional email survey of English-speaking women with a child ⩽1 year old using a convenience sample of women from nine obstetrics and gynecology (OB/GYN) practices in Colorado assessed vaccine hesitancy, knowledge and attitudes about MMR vaccines and the outbreak, MMR vaccination plans before and after the outbreak, and use of and trust for media sources related to the outbreak.ResultsThe response rate was 50% (351/701). Knowledge about the outbreak was high and vaccination attitudes were mostly favorable. Forty-eight percent of respondents thought MMR vaccine was more important after the outbreak. Online news (76%), television news (75%), and social media (68%) were the most frequently used media sources, yet were highly trusted by only 18%, 22%, and 1% of respondents respectively. Government websites (34%) and information from a doctor’s office (34%) were infrequently used, but were highly trusted by 62% and 60% of respondents. Knowledge of the outbreak was lower among vaccine-hesitant respondents. Few mothers changed MMR vaccination plans after the outbreak.ConclusionsNew mothers had high levels of knowledge and favorable attitudes about vaccination after the 2014–15 measles outbreak. Media sources used the most are not the most trusted. Communication about outbreaks of vaccine-preventable diseases should include spread of accurate information to new media sources and strengthening of existing trust in traditional media.     

Waning of measles maternal antibody in infants in measles elimination settings – A systematic literature review

IntroductionMost infants are born with immunity to measles through maternal antibodies transferred in pregnancy, which decay over time. However, in measles elimination settings, where measles does not circulate endemically and most immunity is from immunization rather than infection, maternal antibody levels are lower. This results in infant immunity that wanes earlier, and a wider susceptibility gap between maternal antibody decay and infant immunization than in non-eliminated settings. We aimed to systematically quantify the extent and duration of protection from measles in infants in settings that have sustained measles elimination.MethodsWe conducted a systematic review of studies of measles maternal antibody waning in infants in measles elimination settings. We searched MEDLINE, Embase, CINAHL, Scopus, BIOSIS Previews, and Global Health databases for relevant studies. Studies were included if they were set in countries that had eliminated measles for ≥3 years, and if the study cohort included healthy, full-term, unvaccinated infants ≤12 months, born to healthy mothers, and reported a relevant measure of measles maternal antibody in infants. We assessed study quality using the MetaQAT tool.ResultsWe identified 4692 unique citations, eight of which met inclusion criteria. One study reported anti-measles antibody in cord blood, six reported antibody in infant sera, and one reported both. Two studies reported that 80 and 100% of infants were protected from measles at birth. One study reported no protection amongst 3–7 month old infants, and another reported limited protection in infants >4 months. The remaining studies reported the proportion of infants with detected antibody, but not the proportion immune.ConclusionAlthough limited, these data suggest that in settings that have sustained measles elimination, some infants are susceptible to measles well before the age of routine measles immunization. Setting-specific seroprevalence and vaccine effectiveness studies are required to evaluate this in different jurisdictions.     

Impact of measles national vaccination coverage on burden of measles across 29 Member States of the European Union and European Economic Area, 2006–2011

Background

Challenges in reaching good vaccination coverage against measles emerged in several European Union/European Economic Area Member States (EU/EEA MS) leading to progressive accumulation of susceptible individuals and outbreaks. The Burden of Communicable Diseases in Europe (BCoDE) project developed a methodology for measuring the burden of communicable diseases expressed in Disability-Adjusted Life Years (DALYs) in the EU/EEA MS. The aim of this study was to compare national vaccination coverage and burden of measles across EU/EEA MS.

Methods

Country-specific data on measles national vaccination coverage 2006–2011 from 29 EU/EEA MS (MCV1) were retrieved from Centralized Information System for Infectious Diseases (CISID). DALYs were calculated for each country separately using a disease progression model with a single input parameter (annual measles incidence, adjusted for under-estimation). A software application was used to compute estimated DALYs according to country-specific and year-specific population age-distributions (data retrieved from Eurostat). Log-linear mixed-effect regression modeling approach was used to investigate a linear relation between natural logarithm-transformed DALYs and coverage.

Results

The reported annual vaccination coverage ranged from 72.6% to 100%. The estimated national annual burden ranged from 0 to 30.6 DALYs/100,000. Adjusting for year, there was a significant negative relationship between coverage and burden. For a given country there was a decrease in log-transformed DALYs/100,000 of 0.025 (95% confidence interval: −0.047 to −0.003) for every percentage increase in vaccination coverage. The largest effect of calendar time on estimated burden of measles was observed for the year 2011, the smallest was for the year 2007.

Conclusions

This study shows that the degree of success of national measles vaccination programs, when measured by the coverage obtained, is significantly associated with overall impact of measles across EU/EEA MS. In EU/EEA MS each percentage point increase in national vaccination coverage seems to lead to early significant reduction of overall burden of measles.     

Accelerating measles elimination and strengthening routine immunization services in Guizhou Province,China, 2003–2009

BackgroundTo develop a successful model for accelerating measles elimination in poor areas of China, we initiated a seven-year project in Guizhou, one of the poorest provinces, with reported highest measles incidence of 360 per million population in 2002.MethodsProject strategies consisted of strengthening routine immunization services, enforcement of school entry immunization requirements at kindergarten and school, conducting supplemental measles immunization activities (SIAs), and enhancing measles surveillance. We measured coverage of measles containing vaccines (MCV) by administrative reporting and population-based sample surveys, systematic random sampling surveys, and convenience sampling surveys for routine immunization services, school entry immunization, and SIAs respectively. We measured impact using surveillance based measles incidence.ResultsRoutine immunization coverage of the 1st dose of MCV (MCV1) increased from 82% to 93%, while 2nd dose of MCV (MCV2) coverage increased from 78% to 91%. Enforcement of school entry immunization requirements led to an increase in MCV2 coverage from 36% on primary school entry in 2004 to 93% in 2009. Province-wide SIAs achieved coverage greater than 90%. The reported annual incidence of measles dropped from 200 to 300 per million in 2003 to 6 per million in 2009, and sustained at 0.9–2.2 per million in 2010–2013.ConclusionsThis project found that a package of strategies including periodic SIAs, strengthened routine immunization, and enforcing school entry immunization requirements, was an effective approach toward achieving and sustaining measles elimination in less-developed area of China.     

Risk factors for measles in children aged 8 months–14 years in China after nationwide measles campaign: A multi-site case-control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011, almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012–2013 to identify risk factors for measles infection in children aged 8 months–14 years.MethodsChildren with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program.ResultsIn all, 969 case-patients and 2845 controls were enrolled. In multivariable analysis, lack of measles vaccination both overall (mOR 22.7 [16.6, 31.1] and when stratified by region (east region, mOR 74.2 [27.3, 202]; central/western regions mOR 17.4 [12.5, 24.3]), hospital exposure (mOR 63.0, 95% CI [32.8, 121]), and migration among counties (overall mOR 3.0 [2.3, 3.9]) were significant risk factors. The calculated VE was 91.9–96.1% for a single dose of MCV and 96.6–99.5% for 2 doses.ConclusionsLack of vaccination was the leading risk factor for measles infection, especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities, improving immunization access for migrant children, and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China.     

Description of a large measles epidemic in Democratic Republic of Congo, 2010–2013

Background

Although measles mortality has declined dramatically in Sub-Saharan Africa, measles remains a major public health problem in countries like the Democratic Republic of Congo (DRC). Here, we describe the large measles epidemic that occurred in the Democratic Republic of Congo between 2010 and 2013 using data from the national surveillance system as well as vaccine coverage surveys to provide a snapshot of the epidemiology of measles in DRC.

Methods

Standardized national surveillance data were used to describe measles cases from 2010 to 2013. Attack rates and case fatality ratios were calculated and the temporal and spatial evolution of the epidemic described. Data on laboratory confirmation and vaccination coverage surveys as a part of routine program monitoring are also presented.

Findings

Between week 1 of 2010 and week 45 of 2013, a total of 294,455 cases and 5,045 deaths were reported. The cumulative attack rate (AR) was 0.4%. The Case Fatality Ratio (CFR) was 1.7% among cases reported in health structures through national surveillance. A total of 186,178 cases (63%) were under 5 years old, representing an estimated AR of 1.4% in this age group. Following the first mass vaccination campaigns, weekly reported cases decreased by 21.5%. Results of post-vaccination campaign coverage surveys indicated sub-optimal (under 95%) vaccination coverage among children surveyed.

Conclusions

The data reported here highlight the need to seek additional means to reinforce routine immunization as well as ensure the timely implementation of Supplementary Immunization Activities to prevent large and repeated measles epidemics in DRC. Although reactive campaigns were conducted in response to the epidemic, strategies to ensure that children are vaccinated in the routine system remains the foundation of measles control.

     

Stop measles in Switzerland – The importance of travel medicine

BackgroundIn line with the worldwide strive to combat measles, the Swiss Federal Office of Public Heath (FOPH) launched a National Strategy for measles elimination 2011–2015. In this study, we highlight the importance of travel medicine consultations to complement measles vaccination programmes based on data from the Travel Clinic of the University of Zurich.MethodWe analysed measles vaccination data from the Zurich Travel Clinic between July 2010 and February 2016 and focused on three groups: (i) all clients who received the measles vaccination, (ii) all clients aged > two years who received the measles vaccination (“catch-up vaccination”), and (iii) all clients aged > two years and born after 1963 (“FOPH recommended catch-up vaccination”).Results107,669 consultations were performed from 2010 to 2016. In 12,470 (11.6%) of these, a measles vaccination was administered; 90.9% measles vaccinations were given during a pre-travel consultation, and 99.4% were administered to individuals aged > two years (“catch-up vaccinations”). An “FOPH recommended catch-up vaccination” was received by 13.6% of all Zurich Travel Clinic clients aged >2 years and born after 1963.ConclusionsIn this study, we highlight the importance of travel medicine consultations to enhance the measles vaccination coverage in the adult Swiss population.     

Risk factors for measles infection in 0–7 month old children in China after the 2010 nationwide measles campaign: A multi-site case–control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. We performed a case–control study in six Chinese provinces during January 2012 through June 2013 to identify risk factors for measles infection among children aged 0–7 months.MethodsChildren with laboratory-confirmed measles were neighborhood matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. Adjusted matched odds ratios (mOR) and 95% confidence intervals (CIs) were calculated by multivariable conditional logistic modeling. We calculated attributable fractions for risk factors that could be interpreted as causal.ResultsEight hundred thirty cases and 2303 controls were enrolled. In multivariable analysis, male sex (mOR 1.6 [1.3, 2.0]), age 5–7 months (mOR 3.9 [3.0, 5.1]), migration between counties (mOR 2.3 [1.6, 3.4]), outpatient hospital visits (mOR 9.4 [6.6, 13.3]) and inpatient hospitalization (mOR 107.1 [48.8, 235.1]) were significant risk factors. The calculated attributable fractions for hospital visits was 43.1% (95% CI: 40.1, 47.5%) adjusted for age, sex and migration.ConclusionsHospital visitation was the largest risk factor for measles infection in infants. Improved hospital infection control practices would accelerate measles elimination in China.     

Rash after measles vaccination: laboratory analysis of cases reported in São Paulo,Brazil

OBJECTIVE: The clinical differential diagnosis of rash due to viral infections is often difficult, and misdiagnosis is not rare, especially after the introduction of measles and rubella vaccination. A study to determine the etiological diagnosis of exanthema was carried out in a group of children after measles vaccination. METHODS: Sera collected from children with rash who received measles vaccine were reported in 1999. They were analyzed for IgM antibodies against measles virus, rubella virus, human parvovirus B19 (HPV B19) using ELISA commercial techniques, and human herpes virus 6 (HHV 6) using immunofluorescence commercial technique. Viremia for each of those viruses was tested using a polimerase chain reaction (PCR). RESULTS: A total of 17 cases of children with exanthema after measles immunization were reported in 1999. The children, aged 9 to 12 months (median 10 months), had a blood sample taken for laboratory analysis. The time between vaccination and the first rash signs varied from 1 to 60 days. The serological results of those 17 children suspected of measles or rubella infection showed the following etiological diagnosis: 17.6% (3 in 17) HPV B19 infection; 76.5% (13 in 17) HHV 6 infection; 5.9% (1 in 17) rash due to measles vaccine. CONCLUSIONS: The study data indicate that infection due to HPV B19 or HHV 6 can be misdiagnosed as exanthema due to measles vaccination. Therefore, it is important to better characterize the etiology of rash in order to avoid attributing it incorrectly to measles vaccine.     

Prevaccination screening of health-care workers for immunity to measles, rubella, mumps, and varicella in a developing country: What do we save?

A structured questionnaire was administered to health-care workers (HCWs). The HCWs were also screened for measles, rubella, mumps, and varicella (MMRV) using serological methods. One thousand two hundred and fifty-five HCWs were tested. Of the HCWs examined, 94% were immune to measles, 97% to rubella, 90% to mumps and 98% to varicella. The positive predictive values of histories of measles, mumps, rubella and varicella were 96%, 93%, 100% and 98%, respectively. The negative predictive values of histories of measles, mumps, rubella and varicella were 13%, 17%, 5% and 2%, respectively. The cost of vaccination without screening was significantly more expensive (cost difference: €24,385) for varicella, although vaccination without screening was cheap (cost difference: €5693) for MMR. Although the use of cheaper vaccines supports the implementation of vaccination programs without screening, the cost of vaccination should not be calculated based only on the direct costs. The indirect costs associated with lost work time due to vaccination and its side effects and the direct costs of potential side effects should be considered. However, if prescreening is not conducted, some HCWs (2-7%) would be unprotected against these contagious illnesses because of the unreliability of their MMRV history. In conclusion, the screening of HCWs before vaccination continues to be advisable.     

Seroepidemiology of measles in Catalonia (Spain) 1985–1986

A seroepidemiological study of measles immunological status was carried out among four different populations: schoolchildren of 6–7 years, 10–11 years and 13–14 years, and pregnant women of 18–45 years, in Catalonia, Spain; 1,213 children and 239 pregnant women were surveyed. The measurement of measles antibodies was made by indirect immunofluorescence, with antibody titres 1:8 considered as positive.The prevalence of measles antibodies was 82.9% in the 6–7 year old group, 87.2%, in the 10–11 year old group and 94.4% in the age group 13–14 years. Among pregnant women, the prevalence of antibodies was 96.2%.Two of the variables studied were associated with the prevalence of measles antibodies in schoolchildren: the disease antecedents and measles vaccination. In pregnant women aged 18–45 no variable had any stastically significant association with the prevalence of measles antibodies.     

The economic cost of measles: Healthcare,public health and societal costs of the 2012–13 outbreak in Merseyside,UK

BackgroundMeasles is a highly contagious vaccine-preventable infection that caused large outbreaks in England in 2012 and 2013 in areas which failed to achieve herd protection levels (95%) consistently. We sought to quantify the economic costs associated with the 2012–13 Merseyside measles outbreak, relative to the cost of extending preventative vaccination to secure herd protection.MethodsA costing model based on a critical literature review was developed. A workshop and interviews were held with key stakeholders in the Merseyside outbreak to understand the pathway of a measles case and then quantify healthcare activity and costs for the main NHS providers and public health team incurred during the initial four month period to May 2012. These data were used to model the total costs of the full outbreak to August 2013, comprising those to healthcare providers for patient treatment, public health and societal productivity losses. The modelled total cost of the full outbreak was compared to the cost of extending the preventative vaccination programme to achieve herd protection.FindingsThe Merseyside outbreak included 2458 reported cases. The estimated cost of the outbreak was £4.4 m (sensitivity analysis £3.9 m to £5.2 m) comprising 15% (£0.7 m) NHS patient treatment costs, 40% (£1.8 m) public health costs and 44% (£2.0 m) for societal productivity losses. In comparison, over the previous five years in Cheshire and Merseyside a further 11,793 MMR vaccinations would have been needed to achieve herd protection at an estimated cost of £182,909 (4% of the total cost of the measles outbreak).InterpretationFailure to consistently reach MMR uptake levels of 95% across all localities and sectors (achieve herd protection) risks comparatively higher economic costs associated with the containment (including healthcare costs) and implementation of effective public health management of outbreaks.FundingCommissioned by the Cheshire and Merseyside Public Health England Centre.     

Optimal age for vaccination against measles in the State of São Paulo, Brazil, taking into account the mother's serostatus

In order to investigate if the changing levels of measles antibody in women resulting from extensive vaccination programs influence the susceptibility of children, we measured the seroprevalence of measles virus antibody of children in the first year of life and of their mothers. We compared maternal antibody decay of two groups of children: those whose mothers were 25 years old or more (mothers born in the pre-vaccination era), and less than 25 years old (mothers born in the vaccination era). Therefore, the 25-year-age cut-off was chosen to distinguish between vaccinated and non-vaccinated mothers. We also compared the immunogenicity of measles vaccine in children from 6 to 12 months of age, in these two groups and also according to their mother's serostatus. The optimal age of vaccination for a routine program was estimated by means of mathematical models.This study was carried out in a sample of 1216 mothers and their respective children. Our results indicate that the optimal age for vaccination of the whole sample was 15 months, 17 months for children born from older mothers, 14 months for children born from younger mothers, 17 months for children born from seropositive mothers and 12 months for children born from seronegative mothers. Therefore, a change to an earlier age of routine vaccination is not justified by our results.     

Who are the children at risk? Lessons learned from measles outbreaks

We investigated a measles outbreak in the Jerusalem district in 2007-2008 (992 cases). Most cases (72·6%) were aged <15 years, 42·9% aged <5 years, and 12·8% were infants aged <1 year. The peak incidence rate was in infants aged 6-12 months (916·2/100 000). This represents a significant shift from former outbreaks in 2003-2004, where the peak incidence was in the 1-4 years age group. Of children aged <5 years the proportion aged 6-12 months tripled (7·7% vs. 25·6%). In a case-control study (74 cases, 148 controls) children who developed measles were less likely to be registered in a well-baby clinic and had lower overall immunization coverage. The differences in proportions for registration, DTaP3 and MMR1 coverage were 35·1%, 48·6% and 80·8%, respectively (all P<0·001). Rising birth order of cases and their siblings was associated with non-registration and non-compliance with MMR immunization. The vulnerability of young infants and the risk markers noted above should be taken into account in planning intervention programmes.     

Available studies fail to provide strong evidence of increased risk of diarrhea mortality due to measles in the period 4–26 weeks after measles rash onset

Background

Measles vaccination effectiveness studies showed dramatic decreases in all-cause mortality in excess of what would be expected from the prevention of measles disease alone. This invited speculation that measles infection may increase the risk of diarrhea morbidity and mortality subsequent to the acute phase of the disease. The aim of the present systematic review is to summarize the existing evidence in the publically available literature pertaining to the putative causal link between measles and diarrhea in the period 4–26 weeks following measles rash onset.

Methods

We searched the PubMed, Embase, Open Grey and Grey Literature Report databases for relevant literature using broad search terms. Prospective, retrospective and case-control studies in low- and middle-income countries involving children under five wherein relevant evidence were presented were included. Data were extracted from the articles and summarized.

Results

Fifty abstracts retrieved through the database searches met the initial screening criteria. Twelve additional documents were identified by review of the references of the documents found in the initial searches. Six documents representing five unique studies that presented evidence relevant to the research question were found. Four of the included studies took place in Bangladesh. One of the included studies took place in Sudan. Some measles vaccine effectiveness studies show lower diarrhea morbidity and mortality among the vaccinated. However, children who received vaccine may have differed in important ways from children who did not, such as health service utilization. Additionally, cohort studies following unvaccinated children showed no difference in diarrhea morbidity and mortality between cases and controls more than 4 weeks after measles rash onset. One study showed some evidence that severe measles may predispose children to gastroenteritis, but was not able to show a corresponding increase in the risk of diarrhea mortality.

Conclusions

The available evidence suggests that the risk of measles-associated diarrhea mortality is largely limited to the 5-week period 1 week prior to and 4 weeks after measles rash onset, and that there is no increased risk of diarrhea mortality in the longer-term caused by measles.