Cholera is an acute secretory diarrheal disease that is perceived by World Health Organization (WHO) to be a highly contagious threat. Firstly discovered by an Italian physician, Filippo Pacini, the disease gains a reputation as the most feared epidemic diarrheal disease encountered in developing countries. Despite effort taken by WHO to reduce the incidence rate, cholera-endemic prevail in certain regions. Factors that contribute to the disease transmission and ongoing spreading in cholera-prone areas remain as elusive. Should an awareness and knowledge of cholera be developed, it is the residents of developing nation that stand to benefit the most. This review gives insight into the disease prevalence, pandemic, epidemiology, pathogenesis, disease transmission, major strategies and steps to be pursued toward controlling cholera.
Staphylococci are Gram-positive bacteria that are ubiquitous in the environment and able to form biofilms on a range of surfaces. They have been associated with a range of human health issues such as medical device-related infection, localized skin infection, or direct infection caused by toxin production. The extracellular material produced by these bacteria resists antibiotics and host defence mechanism which complicates the treatment process. The commonly reported Staphylococcus species are Staphylococcus aureus and S. epidermidis as they inhabit human bodies. However, the emergence of other staphylococci, such as S. haemolyticus, S. lugdunensis, S. saprophyticus, S. capitis, S. saccharolyticus, S. warneri, S. cohnii, and S. hominis, is also of concern and they have been associated with biofilm formation. This review critically assesses recent cases on the biofilm formation by S. aureus, S. epidermidis, and other staphylococci reported in health-related environments. The control of biofilm formation by staphylococci using natural compounds is specifically discussed as they represent potential anti-biofilm agents which may reduce the burden of antibiotic resistance.
Bacterial attachment to abiotic surfaces can be explained as a physicochemical process. Mechanisms of the process have been widely studied but are not yet well understood due to their complexity. Physicochemical processes can be influenced by various interactions and factors in attachment systems, including, but not limited to, hydrophobic interactions, electrostatic interactions and substratum surface roughness. Mechanistic models and control strategies for bacterial attachment to abiotic surfaces have been established based on the current understanding of the attachment process and the interactions involved. Due to a lack of process control and standardization in the methodologies used to study the mechanisms of bacterial attachment, however, various challenges are apparent in the development of models and control strategies. In this review, the physicochemical mechanisms, interactions and factors affecting the process of bacterial attachment to abiotic surfaces are described. Mechanistic models established based on these parameters are discussed in terms of their limitations. Currently employed methods to study these parameters and bacterial attachment are critically compared. The roles of these parameters in the development of control strategies for bacterial attachment are reviewed, and the challenges that arise in developing mechanistic models and control strategies are assessed.
Recently, more consumers are interested in purchasing probiotic food and beverage products that may improve their immune health. The market for functional foods and beverages that include Bifidobacterium is expanding because of their potential uses in both food and therapeutic applications. However, maintaining Bifidobacterium's viability during food processing and storage remains a challenge. Microencapsulation technique has been explored to improve the viability of Bifidobacterium. Despite the technical, microbiological, and economic challenges, the market potential for immune-supporting functional foods and beverages is significant. Additionally, there is a shift toward postbiotics as a solution for product innovation, a promising postbiotic product that can be incorporated into various food and beverage formats is also introduced in this review. As consumers become more health-conscious, future developments in the functional food and beverage market discussed in this review could serve as a reference for researchers and industrialist.
Acinetobacter baumannii is a Gram-negative, opportunistic pathogen that causes nosocomial infection with a high mortality rate in immunocompromised individuals. With the frequent emergence of multidrug-resistant A. baumannii strains that have rapidly gained resistance to most antibiotics, an extensive search for an effective A. baumannii vaccine is ongoing. Over the decade, many subunit vaccine candidates were identified using reverse vaccinology and in vivo animal studies for validation. Nineteen subunit vaccine candidates with a wide range of efficacy, from 14% to 100% preclinical survival rates, were included in this review. This article provides an updated review of several outer membrane proteins (Omp) that emerged as vaccine candidates with great potential, including OmpA, Omp34, Omp22 and BamA, based on their high conservancy, antigenicity, and immune protection against A. baumannii infection. However, there is still no licenced A. baumannii vaccine currently due to several practical issues that have yet to be resolved, such as inconsistencies between validation studies, antigen variability and insolubility. Moving forward, much investigation and innovation are still required to tackle these challenges for the regulatory approval of an A. baumannii subunit vaccine, including standardisation of immunisation study parameters, improving antigen solubility and the incorporation of nucleic acid vaccine technology.