A systematic review of adult tetanus-diphtheria-acellular (Tdap) coverage among healthcare workers Bruno A. Randi a,b,⇑ , Odeli Nicole Encinas Sejas a , Karina T. Miyaji a,b , Vanessa Infante a,b , Amanda N. Lara a , Karim Y. Ibrahim a , Marta H. Lopes a,b , Ana Marli C. Sartori a,b a Centro de Referencia para Imunobiologicos Especiais, Divisão de Clinica de Molestias Infecciosas e Parasitarias, Hospital das Clinicas, Sao Paulo, Brazil b Departamento de Molestias Infecciosas e Parasitarias da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, Brazil article info Article history: Received 17 August 2018 Received in revised form 28 November 2018 Accepted 14 December 2018 Available online xxxx Keywords: Diphtheria-tetanus-pertussis vaccine Bordetella pertussis Health personnel Immunization Vaccination Whooping cough abstract During the last decades pertussis incidence raised globally. Several vaccination strategies targeting adults to reduce pertussis among young infants have been proposed, including vaccination of healthcare work- ers (HCWs). The aim of this study was to analyse, by performing a systematic review of literature, pub- lished papers that evaluated Tdap coverage among HCWs, variables associated with vaccine uptake and efforts implemented to raise vaccination rates. We searched the MedLine, Embase, SCOPUS, LILACS, Web of Science and Cochrane for full-text studies that evaluated Tdap coverage in HCW. Two independent reviewers screened the articles and extracted the data. Twenty-eight studies published from 2009 to 2018 were reviewed. Most studies were conducted in the USA. Initial Tdap coverage varied from 6.1% to 63.9%. USA and France are the only two countries with studies evaluating Tdap coverage within HCWs using national data. In the USA, Tdap coverage in HCWs raised from 6.1% to 45.1% from 2007 to 2015. In the analysis of French national data, a Tdap coverage of 63.9% was observed. Five studies used interventions to raise Tdap coverage in HCWs. Two intervention studies implemented mandatory vacci- nation and three used educational strategies. All of them achieved coverages over 86%. Only eleven stud- ies analysed the association of Tdap vaccination with variables of interest. Previous immunization with other vaccines recommended for HCWs (like influenza, hepatitis B and MMR) was positively associated with Tdap uptake in four studies. In conclusion, overall Tdap coverage among HCWs is low, but seems to increase over the years after the vaccine introduction and with implementation of interventions to increase coverage. Ó 2019 Elsevier Ltd. All rights reserved. 1. Introduction Pertussis is an infectious disease caused by Bordetella pertussis, a Gram-negative bacillus transmitted by aerosol droplets [1,2]. It affects people of all ages, but children aged less than one year are the most affected and may have severe disease [3]. Adults usu- ally have milder disease and are the source of infection for young children [1]. During the last decades, pertussis incidence rose glob- ally, despite the sustained high childhood vaccination coverage [2]. Waning immunity after vaccination or infection, reduced effective- ness/shorter duration of protection conferred by acellular pediatric vaccines, increased disease awareness, improved diagnoses and surveillance, and B. pertussis mutations allowing it to escape from vaccine immunity have been proposed to explain pertussis reemergence in developed countries [1,2]. Several vaccination strategies targeting adults to reduce pertus- sis among young infants have been proposed, including vaccina- tion of pregnant women, the cocooning strategy (vaccinating all newborn’s contacts), and vaccination of healthcare workers (HCWs) [1]. Recommendations on the adult tetanus-diphtheria- acellular pertussis (Tdap) vaccination for HCWs vary by country. Some countries, such as the United States, Canada, Australia, Netherlands, Germany and the United Kingdom adopted Tdap vac- cination for all HCWs, while others, such as Austria, Finland, Nor- way and Brazil introduced Tdap only for those in contact with newborns and infants [4]. There are few data about Tdap coverage among HCWs. Thus, the aim of this study was to analyse, by performing a systematic review of literature, all published papers which evaluated Tdap coverage among HCWs, variables associated with the vaccination and efforts implemented to raise vaccination rates. https://doi.org/10.1016/j.vaccine.2018.12.046 0264-410X/Ó 2019 Elsevier Ltd. All rights reserved. ⇑ Corresponding author at: Dr. Ovídio Pires de Campos Street, 225 – Cerqueira César, Zip Code: 05403-010, São Paulo SP, Brazil. E-mail address: bruno_randi@usp.br (B.A. Randi). Vaccine xxx (xxxx) xxx Contents lists available at ScienceDirect Vaccine journal homepage: www.elsevier.com/locate/vaccine Please cite this article as: B. A. Randi, O. N. E. Sejas, K. T. Miyaji et al., A systematic review of adult tetanus-diphtheria-acellular (Tdap) coverage among healthcare workers, Vaccine, https://doi.org/10.1016/j.vaccine.2018.12.046