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Rotavirus Genotypes from Rapid Test Strips | CDC EID


EID Journal Home > Volume 17, Number 1–January 2011
Volume 17, Number 1–January 2011
Research
Genotyping Rotavirus RNA from Archived Rotavirus-Positive Rapid Test Strips

Lester M. Shulman, Comments to Author Ilana Silberstein, Jacqueline Alfandari, and Ella Mendelson


Author affiliations: Central Virology Laboratory, Tel Hashomer, Israel (L.M. Shulman, I. Silberstein, J. Alfandari, E. Mendelson); and Tel Aviv University, Ramat Aviv, Israel (L.M. Shulman, E. Mendelson)

Suggested citation for this article

Abstract
Genotyping circulating rotaviruses before and after introduction of rotavirus vaccine is useful for evaluating vaccine-associated changes in genotype distribution. We determined frequency of rotavirus genotypes among 61 rotavirus-positive children hospitalized in Israel during the 2005–06 rotavirus season. Accurate molecular epidemiologic data were recovered from affinity-concentrated rotavirus immobilized in rotavirus-positive bands from air-dried, diagnostic rotavirus rapid test strips (dipstick) stored at room temperature from 1 week to 5 years. G genotypes were identical for 21 paired dipsticks and suspensions, whereas dipsticks or suspensions detected an additional G genotype in 2 samples. RNA sequences from 7 pairs were identical. Phylogenetic analysis suggested previously unreported G2 sublineages and G9 lineages. The ease with which dipsticks can be stored at local facilities and transported to central reference laboratories can reverse increasing difficulties in obtaining geographically representative stool samples and expand surveillance to regions lacking adequate laboratory facilities.

Rotavirus infection is a leading cause of gastroenteritis in children <5 years of age worldwide; children with severe dehydration and electrolyte imbalance require hospitalization (1). In 2007 and 2008, the annual economic cost for hospitalization of rotavirus case-patients in Israel was US $4,578,489 in direct costs to the health system plus an additional household cost of $3,101,955 (2). Poor hygienic conditions and lack of appropriate medical facilities in developing countries result in high infant mortality rates (1,3–5). The genes encoding the outer capsid viral proteins VP7 and VP4 form the basis of classification of group A rotaviruses into G and P genotypes, respectively (6,7). Two live oral vaccines, monovalent Rotarix vaccine (GlaxoSmithKline, Research Triangle Park, NC, USA) and pentavalent Rotatek vaccine (Merck, Rahway, NJ, USA) effectively reduced hospitalizations for subsequent infections with G1P[8], G2P[4], G3P[8], and G4P[8] rotaviruses by >85% (8,9). Rotavirus vaccines that are scheduled for inclusion in Israel’s national vaccination program after 2010 may selectively change relative distributions of naturally cocirculating rotaviruses of different G and P genotypes. According to analysis of voluntary immunizations before universal vaccination, the effectiveness of rotavirus vaccine in preventing rotavirus gastroenteritis–associated hospitalizations in Israel is already evident (10).

Simple to use, inexpensive, diagnostic rotavirus rapid test strips (dipsticks) identify group A rotavirus–positive stools in <30 minutes by lateral flow immunochromatography without indicating the genotype. Dipsticks are dipped into saline stool suspensions. If rotavirus is present, a colored band appears when indicator-linked rotavirus antibodies bind to the virus, and this complex is trapped on a band of membrane-bound rotavirus antibody on the dipstick. With their growing use at point-of-care facilities and in local hospital laboratories, fewer samples are available for genotyping by centralized reference laboratories. Obtaining geographically representative stool samples and expanding surveillance to regions lacking adequate laboratory facilities is becoming increasingly difficult. The ease with which dipsticks can be stored at local facilities and transported to central reference laboratories can help overcome these difficulties. We hypothesized that rotavirus trapped on rotavirus-specific antibody bands, equivalent to affinity concentrated rotavirus, might yield genotyping-quality RNA from dipsticks that are easily archived locally and transportable to centralized laboratories. In this study, our main objective was to determine the feasibility of recovering molecular epidemiologic data from rotavirus immobilized on air-dried diagnostic rotavirus dipsticks to compensate for the decreasing number of fecal samples reaching central reference laboratories. full-text (large): Rotavirus Genotypes from Rapid Test Strips | CDC EID


Suggested Citation for this Article

Shulman LM, Silberstein I, Alfandari J, Mendelson E. Genotyping rotavirus RNA from archived rotavirus-positive rapid test strips. Emerg Infect Dis [serial on the Internet]. 2011 Jan [date cited].
http://www.cdc.gov/EID/content/17/1/44.htm

DOI: 10.3201/eid1701.101132

Comments to the Authors

Please use the form below to submit correspondence to the authors or contact them at the following address:

Lester M. Shulman, Central Virology Laboratory, Public Health Services, Israel Ministry of Health, Chaim Sheba Medical Center, Tel Hashomer 52621, Israel;
email: lester.shulman@sheba.health.gov.il

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