Dataset Information

Risk Factors for Measles Virus Infection Among Adults During a Large Outbreak in Postelimination Era in Mongolia, 2015.

ABSTRACT:

Background

In 2015, a large nationwide measles outbreak occurred in Mongolia, with very high incidence in the capital city of Ulaanbaatar and among young adults.

Methods

We conducted an outbreak investigation including a matched case-control study of risk factors for laboratory-confirmed measles among young adults living in Ulaanbaatar. Young adults with laboratory-confirmed measles, living in the capital city of Ulaanbaatar, were matched with 2-3 neighborhood controls. Conditional logistic regression was used to estimate adjusted matched odds ratios (aMORs) for risk factors, with 95% confidence intervals.

Results

During March 1-September 30, 2015, 20 077 suspected measles cases were reported; 14 010 cases were confirmed. Independent risk factors for measles included being unvaccinated (adjusted matched odds ratio [aMOR] 2.0, P < .01), being a high school graduate without college education (aMOR 2.6, P < .01), remaining in Ulaanbaatar during the outbreak (aMOR 2.5, P < .01), exposure to an inpatient healthcare facility (aMOR 4.5 P < .01), and being born outside of Ulaanbaatar (aMOR 1.8, P = .02).

Conclusions

This large, nationwide outbreak shortly after verification of elimination had high incidence among young adults, particularly those born outside the national capital. In addition, findings indicated that nosocomial transmission within health facilities helped amplify the outbreak.

SUBMITTER: Hagan JE

PROVIDER: S-EPMC10291145 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Risk Factors for Measles Virus Infection Among Adults During a Large Outbreak in Postelimination Era in Mongolia, 2015.

Hagan José E JE Takashima Yoshihiro Y Sarankhuu Amarzaya A Dashpagma Otgonbayar O Jantsansengee Baigalmaa B Pastore Roberta R Nyamaa Gunregjav G Yadamsuren Buyanjargal B Mulders Mick N MN Wannemuehler Kathleen A KA Anderson Raydel R Bankamp Bettina B Rota Paul P Goodson James L JL

The Journal of infectious diseases 20171201 10

<h4>Background</h4>In 2015, a large nationwide measles outbreak occurred in Mongolia, with very high incidence in the capital city of Ulaanbaatar and among young adults.<h4>Methods</h4>We conducted an outbreak investigation including a matched case-control study of risk factors for laboratory-confirmed measles among young adults living in Ulaanbaatar. Young adults with laboratory-confirmed measles, living in the capital city of Ulaanbaatar, were matched with 2-3 neighborhood controls. Conditiona ...[more]

PMID: 29040627

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Project description:BackgroundCase fatality ratio (CFR) among all age groups during the 2016-2018 measles outbreak in Romania was increased compared with previous outbreaks. To identify risk factors for measles death, we conducted a case-control study among infants and children hospitalized for measles.MethodsNational surveillance data were used to identify hospitalized cases of laboratory-confirmed or epidemiologically linked measles in infants and children aged < 59 months with rash onset from January 2016 to July 2018. We abstracted medical records of 50 fatal cases ("cases") and 250 non-fatal cases ("controls") matched by age, sex, district of residence, and urban/rural place of residence. We calculated univariable and multivariable matched odds ratios (OR) and 95% confidence intervals (CIs) for risk factors.ResultsNinety-three percent of case-patients and controls had not received a valid dose of a measles-containing vaccine; only 5 % received Vitamin A supplementation once diagnosed with measles. In the univariable analysis, cases were more likely than controls to have had a healthcare-related exposure to measles manifesting as inpatient admission for pneumonia during the 7 to 21 day measles incubation period (OR: 3.0; 95% CI [1.2, 7.2]), to have had a history of malnutrition (OR: 3.4; 95% CI [1.1, 9.9]), and to have had pneumonia as a complication of measles (OR:7.1; 95% CI [2.0-24.8]). In the multivariable analysis, pneumonia as a measles complication remained a risk for death (OR: 7.1; 95% CI [1.4-35.3]).ConclusionsImplementing infection prevention and control practices, ensuring immunization of healthcare workers, and hospitalizing only severe measles cases may minimize the risk of nosocomial measles transmission. Implementing World Health Organization (WHO) recommendations for Vitamin A supplementation, improving immunization of children to prevent influenza, pneumococcal, and other bacterial respiratory diseases may decrease complications and deaths due to measles in Romania.

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Dataset Information

Risk Factors for Measles Virus Infection Among Adults During a Large Outbreak in Postelimination Era in Mongolia, 2015.

Background

Methods

Results

Conclusions

Publications

Risk Factors for Measles Virus Infection Among Adults During a Large Outbreak in Postelimination Era in Mongolia, 2015.

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