Short-term Prediction of the Incidence of Congenital Rubella Syndrome

Yasushi Ohkusa; Tamie Sugawara; Satoru Arai; Hiroshi Satoh; Hideo Okuno; Keiko Tanaka-Taya; Kazunori Oishi

doi:10.1371/currents.outbreaks.8c74272f4348781c5d01c81e6150c2f7

Short-term Prediction of the Incidence of Congenital Rubella Syndrome

PLoS Curr. 2014 Oct 30:6:ecurrents.outbreaks.8c74272f4348781c5d01c81e6150c2f7. doi: 10.1371/currents.outbreaks.8c74272f4348781c5d01c81e6150c2f7.

Authors

Yasushi Ohkusa¹, Tamie Sugawara¹, Satoru Arai¹, Hiroshi Satoh¹, Hideo Okuno¹, Keiko Tanaka-Taya¹, Kazunori Oishi¹

Affiliation

¹ Infectious Disease Surveillance Center, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan.

PMID: 25642379
PMCID: PMC4234431
DOI: 10.1371/currents.outbreaks.8c74272f4348781c5d01c81e6150c2f7

Abstract

Objectives In Japan, a rubella outbreak occurred from early 2012 to late 2013, primarily among adult males aged 20-49 years. We conducted this study to predict the number of congenital rubella syndrome (CRS) cases in Japan in 2014. Methods The probability of CRS when a pregnant woman is infected with rubella depends on the gestational age of the fetus. The cumulative number of CRS cases was predicted by a formula based on the parameters from two studies conducted in the U.K. and the U.S., the reported cases of rubella among women 15-49 years of age, and the reports of CRS from 2011 to week 2 of 2014. Findings While the predicted number of cases of CRS based on parameters from the U.K. study demonstrated a biphasic curve, with a low peak around week 12 and a high peak around week 50 of 2013, the predicted number of CRS cases based on the U.S. study demonstrated a single peak around week 50 of 2013. The ex post evaluation indicated that the cumulative number of CRS cases in 2014 would be 19.1-29.3. Interpretation Our prediction of the number of CRS cases may be useful for the enhanced detection of this often under-reported syndrome.

Keywords: Surveillance; congenital rubella syndrome; public health policy; rubella; short-term prediction.

Grants and funding

This work was supported by research grants from the Ministry of Health, Labour, and Welfare of Japan, http://www.mhlw.go.jp/english/policy/other/research-projects/index.html, and grant code was Research on Emerging and Re-emerging Infectious Diseases No. 003 (2013). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.