Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jan 15;13(1):75.
doi: 10.3390/vaccines13010075.

Development of RT-PCR Assays for Simple Detection and Identification of Sabin Virus Contaminants in the Novel Oral Poliovirus Vaccines

Olga Singh  1 , Hasmik Manukyan  1 , Erman Tritama  2 , Shwu-Maan Lee  3 , Jerry P Weir  1 , Majid Laassri  1
Affiliations

Development of RT-PCR Assays for Simple Detection and Identification of Sabin Virus Contaminants in the Novel Oral Poliovirus Vaccines

Olga Singh et al. Vaccines (Basel). .

Abstract

Background/objectives: Conventional live oral poliovirus vaccines (OPVs) effectively prevent poliomyelitis. These vaccines are derived from three attenuated Sabin strains of poliovirus, which can revert within the first week of replication to a neurovirulent phenotype, leading to sporadic cases of vaccine-associated paralytic poliomyelitis (VAPP) among vaccinees and their contacts. A novel OPV2 vaccine (nOPV2) with enhanced genetic stability was developed recently; type 1 and type 3 nOPV strains were engineered using the nOPV2 genome as a backbone by replacing the capsid precursor polyprotein (P1) with that of Sabin strains type 1 and type 3, respectively. The nOPV vaccines have a high degree of sequence homology with the parental Sabin 2 genome, and some manufacturing facilities produce and store both Sabin OPV and nOPV. Therefore, detecting Sabin virus contaminations in nOPV lots is crucial.

Methods: This study describes the development of pan quantitative reverse transcription polymerase chain reaction (panRT-PCR) and multiplex one-step RT-PCR (mosRT-PCR) assays for the straightforward detection and identification of contaminating Sabin viruses when present in significantly higher amounts of nOPV strains.

Results: The two assays exhibit high specificity, reproducibility, and sensitivity to detect 0.0001% and 0.00001% of Sabin viruses in nOPV, respectively. Additionally, an analysis of 12 trivalent nOPV formulation lots using both methods confirmed that the nOPV lots were free from Sabin virus contamination.

Conclusions: The results demonstrated that the RT-PCR assays are sensitive and specific. These assays are relevant for quality control and lot release of nOPV vaccines.

Keywords: OPV; RT-PCR; nOPV; poliovirus; vaccines; viral contamination; viral detection.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Genomic location of primers and TaqMan probes used for detection and identification of Sabin viruses in nOPV vaccines: (A) primers and TaqMan probe used in panRT-PCR assay; (B) primers and TaqMan probes used in mosRT-PCR assay for detection and Sabin 1 and 3 strains.
Figure 2
Figure 2
Evaluation of the assays’ specificity. (A) panRT-PCR assay; (B) mosRT-PCR assay.
Figure 3
Figure 3
Evaluation of sensitivity and linearity of the panRT-PCR assay (Three repeats were used): Analysis of samples composed of individual Sabin strains and the three Sabin strains mixture spiked in the tOPV. Percentages of Sabin viruses in the tnOPV were calculated based on the titers of the viruses expressed on genome copy number (GC#)/mL.
Figure 4
Figure 4
Evaluation of sensitivity and linearity of the mosRT-PCR assay (Three repeats were used): (A) analysis of samples composed of individual Sabin strains spiked in the tnOPV; (B) analysis of samples composed of the three Sabin strains mixture spiked in the tnOPV. Percentages of Sabin viruses in the tnOPV were calculated based on the titers of the viruses expressed on genome copy number (GC#)/mL.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Sutter R.W.K.O., Cochi S.L., Aylward R.B. Poliovirus vaccine–live. In: Plotkin S.A.O.W., Offit P.A., editors. Vaccines. 6th ed. Elsevier; Amsterdam, The Netherlands: 1993. pp. 598–645.
    1. Yakovenko M.L., Korotkova E.A., Ivanova O.E., Eremeeva T.P., Samoilovich E., Uhova I., Gavrilin G.V., Agol V.I. Evolution of the Sabin vaccine into pathogenic derivatives without appreciable changes in antigenic properties: Need for improvement of current poliovirus surveillance. J. Virol. 2009;83:3402–3406. doi: 10.1128/JVI.02122-08. - DOI - PMC - PubMed
    1. WHO Global Eradication of Wild Poliovirus Type 2 Declared. Declaration Further Milestone for Globally-Coordinated Vaccineswitch in 2016. [(accessed on 20 September 2015)]. Available online: https://polioeradication.org/news/global-eradication-of-wild-poliovirus-....
    1. WHO Two out of Three Wild Poliovirus Strains Eradicated. Global Eradication of Wild Poliovirus Type 3 Declared on World Polio Day 2019. [(accessed on 24 October 2019)]. Available online: https://polioeradication.org/news/two-out-of-three-wild-poliovirus-strai...
    1. John J., Giri S., Karthikeyan A.S., Iturriza-Gomara M., Muliyil J., Abraham A., Grassly N.C., Kang G. Effect of a single inactivated poliovirus vaccine dose on intestinal immunity against poliovirus in children previously given oral vaccine: An open-label, randomised controlled trial. Lancet. 2014;384:1505–1512. doi: 10.1016/S0140-6736(14)60934-X. - DOI - PubMed

LinkOut - more resources