The burden of pertussis in low- and middle-income countries since the inception of the Expanded Programme on Immunization (EPI) in 1974: a systematic review protocol.
BACKGROUND
Vaccine against pertussis has been in use for several decades. Despite the widespread use of pertussis vaccine, evidence shows resurgence of pertussis in high-income countries. Pertussis surveillance data is largely missing from low- and middle-income countries (LMICs). Without data on trends of pertussis, it is difficult to review and amend pertussis control policies in any country. We propose conducting a systematic review to evaluate the burden and trends of pertussis in LMICs since 1974.


METHODS
Common and medical subject heading (MeSH) terms for pertussis and LMICs will be used to search electronic databases for the relevant literature published between 1974 and December 2014. Only studies from LMICs that fulfils World Health Organisation (WHO) or CDC pertussis case definitions will be included. The studies must have a clear numerator and denominator in a well-defined population. Risk of bias will be evaluated by assessing all qualifying full-text articles for quality and eligibility using a modified quality score assessment tool. Standardised data extraction will be carried out after which descriptions of trends in the prevalence, incidence, as well as mortality rate and case fatality rate, will be done. Where sufficient data is available, the results will be stratified by age group, geography, location, vaccination and HIV status.


CONCLUSIONS
The systematic review proposed by this protocol seeks to address the knowledge gap in the epidemiology of pertussis in LMICs for the first time. It is anticipated that the background epidemiological trends of pertussis in LMICs that our study will provide could be used in the planning for the control of pertussis.


BACKGROUND
PROSPERO CRD42015015159.
Department of Paediatrics & Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Rondebosch, Cape Town 7700, South Africa. Rudzani.Muloiwa@uct.ac.za.
Rudzani
R
Muloiwa
Vaccines for Africa Initiative, Division of Medical Microbiology & Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, Cape Town, 7925, South Africa. bm.kagina@uct.ac.za.
Benjamin M
BM
Kagina
Department of Medicine, University of Cape Town, Observatory, Cape Town, 7925, South Africa. Mark.Engel@uct.ac.za.
Mark E
ME
Engel
Vaccines for Africa Initiative, Division of Medical Microbiology & Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, Cape Town, 7925, South Africa. Gregory.Hussey@uct.ac.za.
Gregory D
GD
Hussey
D002985:Clinical Protocols; D003906:Developing Countries; D014943:Global Health / Q000639:trends*; D006801:Humans; D017589:Immunization Programs; D007182:Income; D012107:Research Design; D000078202:Systematic Reviews as Topic; D014611:Vaccination; D014917:Whooping Cough / Q000453:epidemiology* / Q000517:prevention & control