Non-specific effects of veterinary vaccines: a systematic review. Issue 11 (8th March 2022)

• Record Type: Journal Article
• Authors: Arega, Sintayehu M.; Knobel, Darryn L.; Toka, Felix N.; Conan, Anne
• Is Part Of: Vaccine. Volume 40:Issue 11(2022)
• Page Start: 1655
• Page End: 1664
• Publication Date: 2022-03-08
• Subjects: Animal -- Heterologous effect -- Non-specific effect -- Review -- Vaccine -- Veterinary; BCG Bacillus Calmette-Guérin -- DTP Diphtheria-tetanus-pertussis -- MMV Mumps-measles vaccine -- NSE Non-specific effect -- RCT Randomised Clinical Trial; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2021.11.034
• Languages: English
• ISSNs: 0264-410X

Abstract

Highlights: Current evidence for NSE of vaccines are mainly from studies in humans. NSE of vaccines have been reported in animal studies since the 1950s. This review paper highlights the potential evidence for NSE of veterinary vaccines. Various types of vaccines and subjects should be included in studies assessing NSE. Several animal vaccines could be exploited for their added beneficial NSE. Abstract: The benefits of vaccines have been centred on their specific effects on subsequent infections by target pathogens. Recent studies, however, have opened up new insights into additional effects of vaccines known as non-specific effects (NSEs) or heterologous effects of vaccines. While several articles have reviewed epidemiological and immunological evidence for NSEs of vaccines in humans, similar works on veterinary vaccines are scarce. The objective of this paper was to review the findings of published studies on NSEs of vaccines developed or repurposed for use in animals. In total 8412 titles were retrieved from PubMed and CABI databases on the 30 th of April 2021. After the final stage of screening, 45 eligible articles were included in the review. Data from these articles were summarised and presented here. In general, most of the vaccines studied in the reviewed articles have beneficial NSEs against multiple pathogens and disease conditions. There were, however, fewe studies reporting detrimental NSEs from both non-live and live vaccines which is in contrast to the currently existing evidence of beneficial NSEs of live vaccines and detrimental NSEs of non-live vaccines. This review may be used as a complement for future review of RCT studies of NSEs of vaccines in animals and provide a useful addition to the evolving understanding of the NSEs of vaccines.