THREE CASES OF CONGENITAL RUBELLA SYNDROME IN THE POST ELIMINATION ERA — MARYLAND, ALABAMA, AND ILLINOIS, 2012

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[source]Morbidity and Mortality Weekly Report (MMWR)[|source]

Documented imported CRS cases into the US from Africa are documented here. Full text details are available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6212a3.htm?s_cid=mm6212a3_w

Abstract

Since 2004, when rubella and CRS elimination were documented in the United States, six cases of CRS have been reported, including the three cases described here. In five cases, infection of the mother in a foreign country was thought highly probable, given travel history (i.e., Nigeria, Tanzania, Sudan, Ivory Coast, and either India, China, or Singapore). In one case, the mother did not report international travel. Although few cases of CRS have been reported in the United States, rubella continues to circulate in many other parts of the world, and the risk remains for severe effects from CRS, including death. In this report, one of the three infants with CRS died.

In 2011, a total of 130 countries, comprising approximately 41% of the world's birth cohort, included rubella-containing vaccine in their national childhood immunization program (5). However, in the African Region, only three countries have introduced rubella-containing vaccine into their routine childhood vaccination program. In 2009, the Region of the Americas reached its 2010 rubella and CRS elimination goal. The European Region and Western Pacific Region have rubella control or elimination goals, but rubella continues to circulate in these regions. The African, Eastern Mediterranean, and South-East Asia regions do not have a regional rubella or CRS control or elimination goal at this time because of the additional cost of the rubella component and competing priorities (e.g., polio eradication).

Health-care providers should consider CRS if the mother of an infant with compatible congenital birth defects traveled during her pregnancy to an area where rubella circulates or was exposed to someone who traveled to such an area. As a nationally notifiable condition, all suspected cases of CRS should be reported immediately to the local health department, which, in turn, reports them to CDC via the state health department. Both serum and throat swab specimens should be collected as soon as CRS is suspected. Either serum positive for rubella IgM antibody or a throat swab positive for rubella RNA is confirmatory for CRS in a patient with compatible signs.

At this time, during maintenance of CRS elimination in the United States, confirmation at CDC of all laboratory results that support diagnoses of CRS cases is recommended. Molecular characterization of the virus is critical because the viral genotype can substantiate the suspected source of the virus or suggest one if the source is unknown, because some of the circulating genotypes are associated with specific geographic areas. Heightened awareness, gathering of pertinent information, and collection of appropriate specimens are required of the health-care provider and public health department to diagnose and investigate a case of CRS; however, these surveillance efforts are crucial to maintaining elimination in the United States.

As long as rubella remains endemic in any area of the world, imported CRS will continue to be a public health concern in the United States. Residents or foreign visitors entering the United States from rubella-endemic areas can introduce the virus. In addition, infants born with CRS can shed infectious virus for several months; therefore, care must be taken to avoid contact with others who are susceptible to rubella (e.g., unvaccinated infants in day-care settings). Although levels of vaccination with rubella-containing vaccine are high in the United States, a small proportion of persons are not vaccinated for medical or personal reasons. Those who are not vaccinated against rubella virus can become infected if exposed. If a pregnant woman is infected with rubella virus, the fetus also can become infected. Fetal infection with rubella virus, especially early during pregnancy, often leads to CRS. The risk for CRS in the unborn child of a mother with rubella infection might be as high as 90% for infections occurring through week 10 of pregnancy. Clusters of unvaccinated persons are at high risk of an outbreak, as in the Netherlands and Canada in 2009. Health-care providers and public health workers should remain vigilant for imported cases of CRS.