A prospective study of bacillus Calmette-Guérin scar formation and tuberculin skin test reactivity in infants in Lima, Peru.

Abstract

OBJECTIVES:

To determine the sensitivity of the bacillus Calmette-Guérin (BCG) scar as an indicator of previous vaccination and to ascertain the tuberculin skin test (TST) response in infancy after vaccination in a community from an area hyperendemic for tuberculosis (TB).

METHODS:

In a birth cohort of healthy term infants from Lima, Peru, a single dose of BCG vaccine was administered within the first month of life. Scar formation was assessed biweekly during the first 6 months and again at 3 years after vaccination. TST response was evaluated 6 months after vaccination.

RESULTS:

Six months after vaccination, 99% (68) of the newborns exhibited a BCG scar (>2 mm). Scar size did not differ by sex, birth weight, age at vaccination, or nutritional status in the first 2 months. Eighty percent of the participants were found 3 years after vaccination, and all of them had a BCG scar. Mean TST reaction size 6 months after vaccination was 2.9 +/- 0.3 mm. No association was found between sex or age at BCG vaccination and TST size. Only 3 children had a TST >10 mm, and the 3 had a TB contact at home.

CONCLUSIONS:

The BCG scar was a sensitive indicator of vaccination status up to 3 years after the administration of the vaccine in the first month of life. Although nearly a quarter of the children had a TST response >5 mm 6 months after vaccination, TST reactions >10 mm did not occur in the absence of exposure to a person with tuberculosis. A cutoff of 10 mm should be used for disease control purposes in people who are born in countries where TB is endemic.

• Authors: Eunice M Santiago, Elise Lawson, Kari Gillenwater, Sheela Kalangi, Andrés G Lescano, Gregory Du Quella, Kristin Cummings, Lilia Cabrera, Cecilia Torres, Robert H Gilman
• Journal: Pediatrics (Pediatrics) Vol. 112 Issue 4 Pg. e298 (Oct 2003) ISSN: 1098-4275 [Electronic] United States
• PMID: 14523215 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Antibodies, Bacterial
• BCG Vaccine

Topics

• Antibodies, Bacterial (biosynthesis)
• BCG Vaccine (immunology)
• Cicatrix (epidemiology, etiology)
• Cohort Studies
• Female
• Follow-Up Studies
• Growth Disorders (epidemiology, immunology)
• Humans
• Infant, Newborn
• Male
• Mycobacterium tuberculosis (immunology)
• Nutrition Disorders (epidemiology, immunology)
• Peru (epidemiology)
• Poverty Areas
• Prospective Studies
• Seroepidemiologic Studies
• Tuberculin Test (statistics & numerical data)
• Vaccination (statistics & numerical data)