Details

Autor(en) / Beteiligte

• Huyen, Dang Thi Thanh
• Mach, Ondrej
• Thanh Trung, Nguyen
• Thai, Pham Quang
• Thang, Ho Vinh
• Weldon, William C
• Oberste, M Steven
• Jeyaseelan, Visalakshi
• Sutter, Roland W
• Anh, Dang Duc

Titel

Rapid Disappearance of Poliovirus Type 2 (PV2) Immunity in Young Children Following Withdrawal of Oral PV2-Containing Vaccine in Vietnam

Ist Teil von

• The Journal of infectious diseases, 2019-07, Vol.220 (3), p.386-391

Ort / Verlag

United States: Oxford University Press

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• Due to global shortage of inactivated poliovirus vaccine and withdrawal of oral vaccine containing poliovirus type 2 (PV2), a PV2-containing vaccine was not used in Vietnam May 2016 to October 2018. We assessed the population immunity gap to PV2. A cross-sectional survey in children aged 1-18 months was carried out in January 2018. One blood sample per child was analyzed for presence of poliovirus neutralizing antibodies. In children with detectable anti-PV2 antibodies, a second sample was analyzed 4 months later to distinguish between passive (maternally derived) and active (induced by secondary transmission or vaccination) immunity. Sera were obtained from 1106/1110 children. Seroprevalence of PV2 antibodies was 87/368 (23.6%) at age 1-7 months, 27/471 (5.7%) at 8-15 months, and 19/267 (7.1%) at 16-18 months. Seroprevalence declined with age in the 1-7 months group; in the 8-18 months group there was no significant change with age. Four months later, 11/87 (14%), 9/27 (32%), and 12/19 (37%) remained seropositive in 1-7, 8-15, and 16-18 months age groups, respectively. We found declining immunity to PV2, suggesting Vietnam is at risk for an outbreak of type 2 vaccine-derived poliovirus following virus importation or new emergence.