Brucella melitensis vaccines: A systemiatic review

Authors: ALNAKHLI, NASEER - Colorado State University; SALMAN, MO - Colorado State University; Olsen, Steven; MCCLUSKEY, BRIAN - Animal And Plant Health Inspection Service (APHIS)

Submitted to: Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/6/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary: Brucella melitensis is a reproductive disease predominantly in domestic livestock which can also be a zoonotic issue in humans. Control of B. melitensis in sheep and goats is primarily through a live attenuated strain known as Rev1. However, Rev1, which was developed in the 1950s, is pathogenic in humans and animals and induces antibody responses that interfere with identification of infected animals. Therefore, there is a need to develop a safer and more efficacious vaccine for brucellosis in small ruminants. For this manuscript, the literature was reviewed to identify new vaccine candidates and associated knowledge as a systematic approach for developing a new brucellosis vaccine. . A number of potential candidates are reviewed and an approach for vaccine development is presented.. This work will be of interest to researchers, public health officials, and regulatory officials with an interest in brucellosis in small ruminants.

Technical Abstract: Live attenuated vaccine Rev1 is currently the most effective vaccine for controlling B. melitensis in small ruminants. While Brucella inactivated, nanoparticle and subunit vaccines are less effective and require multiple doses, live-attenuated vaccines are less expensive and more efficacious. Several drawbacks are associated with administration of current attenuated B. melitensis vaccines including: interference with serological diagnostic tests, inducing abortion in pregnant animals, shedding in milk, and zoonotic infections in humans. In this systematic review, we summarize current literature on B.melitensis vaccines and review their advantages and disadvantages to guide design and manufacture of improved small ruminant brucellosis vaccines. Methods: Peer-reviewed articles published between 1970 and 2022 were identified using Web of Science, google scholar, and PubMed. We extracted information from articles applying B. meltensis vaccines which may be effective to protect against small ruminants against infection. Results: We identified 17 articles and 1 book evaluating B.meltensis vaccines, including recombinant B. melitensis strains (16M'hfq,16M'TcfSR, M5-90'manB , LVM31, M5-90'vjbR, 16M'mucR,'znuA, M5-90'pgm, M5-90'wboA ), live B. melitensis strain (Rev1 ), nanoparticle vaccines (B. melitensis 16M, B. melitensis OMP 31, FliC protein - Mannosylated Chitosan Nanoparticles (FliC and FliC-MCN), B. melitensis and B. abortus combined ,and B. melitensis 16M nanoparticles combined with oligopolysaccharide), subunit vaccines (outer membrane vesicles or outer membrane proteins) and a DNA vaccine based on B. melitensis outer membrane proteins (Omp25 and Omp31). We describe these vaccines while addressing their advantages and disadvantages. Conclusions : High prevalence of B. melitensis in humans and animals remains an issue in many parts of the world. The most economical method control of brucellosis is by use of efficacious vaccines in livestock reservoirs. Prospective vaccines have limitations including: interference with serodiagnostics after vaccination, virulence in humans and animals, require booster vaccinations, and insufficient efficacy in preventing infection or abortion. Our review suggests a need for additional research into molecular pathology and immunological properties of B. melitensis infection, and identification of protective epitopes or genes that would allow development of improved vaccines for small ruminants.