Table 7 Summary of key findings from data synthesis

Human resource challenges

Challenges experienced by pharmacists with the various aspects of the supply chain

Lack of support for personnel involved in medicine logistics, inadequate personnel, lack of human resources as well as corruption, killing of personnel due to insurgency

(Chukwu et al., 2018) (Eboreime et al., 2015) (Chukwu et al., 2017)

(Mohammed & Magaji, 2007)

(Aigbavboa & Mbohwa, 2020)

Financial challenges

Lack of financial resources, Poor funding for vaccine supply

(Mohammed & Magaji, 2007)

(Chukwu et al., 2018)

(Sarley et al., 2017)

(Omole et al., 2019)

(Obioha et al., 2010)

Delay, transportation and distributions challenges

Delays in importation and difficulty in maintaining delivery vehicles. Distribution challenge due to delay in submission of inventory reports and submission of inaccurate inventory reports, insecurity during transportation of vaccines and logistics distance between manufacturer and Nigeria. Inability to monitor and maintain optimum temperatures for vaccines during transportation

(Palafox et al., 2014)

(Jatau et al., 2015)

(Omole et al., 2019)

(Oli et al., 2017)

(Ogbuabor, 2020)

Policies and Standard Operating Procedure (SOP) challenges

Inadequate implementation of medicine distribution policies, sub-optimal implementation of policies, non-adherence to policies

(Chukwu et al., 2017)

(Amadi & Tsui, 2019)

(Chukwu et al., 2018)

(Scotney et al., 2017)

Infrastructure and storage challenges

Disruption of the supply chain through the destruction of storage facilities, inadequate storage facilities for ivermectin, inadequate cold storage facilities, inadequate ice-packs

(Aigbavboa & Mbohwa, 2020)

(Surakat et al., 2018)

(Shittu et al., 2016)

(Ashok et al., 2017)

(Sarley et al., 2017)

(Ameen et al., 2013)

Issues including medicines or vaccines stockouts

Stock-outs, substandard medicines, shortage of vaccine stock and vaccine stock-outs, Regular stock-outs of essential medicines due to inefficient inventory management systems, equipment and corruption, Inadequate supply of vaccines

(Aigbavboa & Mbohwa, 2020) (Babalola 2011)

(Sato, 2019)

(Gooding et al., 2019)

(Chukwu et al., 2018)

(Obioha et al., 2010)

(Mohammed & Magaji, 2007)

(Breakwell et al., 2017)

Technical issues

Interruption of drug supplies, Unreliable vaccine supply, Inefficient procurement systems, Damaged products and packages, loss of potency of cold chain medical supplies, Irregular power supply and use of archaic technology in vaccine handling, inadequate ice blocks to maintain a cold chain

(Breakwell et al., 2017)

(Ogbuabor, 2020)

(Babar et al., 2013)

(Dairo & Osizimete, 2016) (Ashok et al., 2017)

(Onyeka et al., 2014)

Poor data management of medicines and vaccines supply

Poor procurement, incomplete forecasting, poor data collection, use and management, Poor reliability and availability of data for forecasting and decision making, Sub-optimal data on vaccine stock, Poor reliability and availability of data for forecasting and decision making

(Chukwu et al., 2018)

(Omole et al., 2019)

(Wallace et al., 2017)