[Source: PLoS One, full page: (LINK). Abstract, edited.]
OPEN ACCESS / PEER-REVIEWED / RESEARCH ARTICLE
Human response to live plague vaccine EV, Almaty region, Kazakhstan, 2014-2015
Zaurbek Sagiyev , Almas Berdibekov , Tatyana Bolger , Almagul Merekenova , Svetlana Ashirova , Zamir Nurgozhin ,Zhandos Dalibayev
Published: June 14, 2019 / DOI: https://doi.org/10.1371/journal.pone.0218366
In Kazakhstan, a live plague vaccine EV 76 NIIEG has been used for plague prophylaxis since the mid-1930s. Vaccination is administered yearly among people living in plague-enzootic areas. Similar practices are used in other former Soviet Union countries. Yet, to this day, the effectiveness period of the vaccine is unknown. It is also not clear how different factors can affect the effectiveness of the vaccine over time.
We surveyed changes in antibody levels specific for F1 antigens of Yersinia pestis among vaccinated people 4, 8, and 12 months post- vaccination. Blood samples were taken from the participants of the study for producing sera, which was later analyzed using indirect hemagglutination reaction with antigenic erythrocyte assay (micromethod) for identifying antibodies to F1 Y.pestis.
In first-time-receivers of the plague vaccine, antibody titer reached the highest level of antibody that represents a conditionally protective titer after 4 months, dropped drastically after 8 months, and dropped again after 12 months. Similar results were obtained among those who have been vaccinated previously. However, in that group, the percentage of people with a level of antibody that represents a conditionally protective titer remained statistically significant even after 8 and 12 months.
Based on the results of this study, we recommend initiating vaccination campaigns for the medical and veterinary staff, as well as the general population four months prior to the springtime epizootics of plague among wild rodents.
Citation: Sagiyev Z, Berdibekov A, Bolger T, Merekenova A, Ashirova S, Nurgozhin Z, et al. (2019) Human response to live plague vaccine EV, Almaty region, Kazakhstan, 2014-2015. PLoS ONE 14(6): e0218366. https://doi.org/10.1371/journal.pone.0218366
Editor: Chandra Shekhar Bakshi, New York Medical College, UNITED STATES
Received: October 31, 2018; Accepted: June 1, 2019; Published: June 14, 2019
Copyright: © 2019 Sagiyev et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the paper and its Supporting Information files.
Funding: The study was conducted under FELTP CDC/CAR, 2013-2015 (CDC Field Epidemiology and Laboratory Training Program) to ZS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
Keywords: Plague; Yersinia pestis; Vaccines; Serology; Kazakhstan.