Yellow fever: World Health Organization (WHO) authorizes emergency expansion of global vaccine stocks by using fractionated doses

WHO has published a statement endorsing the emergency use of fractionated doses of the vaccine to stretch global stockpile which is being rapidly depleted with requests from at-risk countries not only in Africa but also in Latin America.

“1. Preamble

This document represents the World Health Organization (WHO) Secretariat position on the use of yellow fever (YF) vaccine in the context of supply shortages in response to the current outbreak in Africa in 2016. The development of this paper was led by the WHO Initiative for Vaccine Research with contributions to specific sections from the WHO Departments of Pandemic and Epidemic Diseases, Essential Medicines, and Immunization Vaccines and Biologicals. The evidence and the proposed recommendations, reflected in this document, has been discussed with YF experts and reviewed by the WHO Strategic Advisory Group of Experts (SAGE) on Immunization. SAGE and the YF experts provided input to this paper. The recommendations were vetted by SAGE, but they don’t represent a formal SAGE recommendation. The paper will be updated as additional data become available. A full review on the use of fractional dose YF vaccine will be conducted by SAGE in October 2016.

2. Introduction

Ongoing YF outbreaks are sharply increasing the demand for YF vaccine, exhausting the global stockpile and putting at risk the immunization of endemic populations. The campaigns currently planned have led to a shortage of the vaccine, a situation which could deteriorate further should expansion of outbreaks necessitate additional immunization campaigns on a large scale. An assessment of existing opportunities to increase the availability of vaccine in response to ongoing outbreaks is therefore urgently required. This paper reviews the evidence on dose-sparing strategies through fractional dosing of YF vaccine as an immediate and short-term option to meet the needs of large-scale campaigns, and proposes recommendations for fractional dose vaccination in case of imminent need in the context of outbreak response. The paper is intended to support efforts to introduce YF vaccine fractional dose use in situations where supply capacity is threatened or inadequate, e.g. following the spread of YF into densely populated areas. This is not proposed as a longer-term strategy or to replace established routine immunization practices.” ...

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Provided July 22, 2016 by: 

Jack Woodall, PhD

Co-founder & Assoc.Ed. 


Former member One Health Initiative Team