Extraintestinal pathogenic E . coli (ExPEC) are facultative pathogens that are part of the normal human intestinal flora. The ExPEC group includes uropathogenic E. coli (UPEC), neonatal meningitis E. coli (NMEC), sepsis-associated E. coli (SEPEC), and avian pathogenic E. coli (APEC). Virulence factors (VF) related to the pathogenicity of ExPEC are numerous and have a wide range of activities, from those related to bacteria colonization to those related to virulence, including adhesins, toxins, iron acquisition factors, lipopolysaccharides, polysaccharide capsules, and invasins, which are usually encoded on pathogenicity islands (PAIs), plasmids and other mobile genetic elements. Mechanisms underlying the dynamics of ExPEC transmission and the selection of virulent clones are still poorly understood and require further research. The time shift between colonization of ExPEC and the development of infection remains problematic in the context of establishing the relation between consumption of contaminated food and the appearance of first disease symptoms. What appears to be most difficult is to prove that ExPEC strains cause disease symptoms and to examine the mechanism of transition from the asymptomatic colonization of the intestines to the spreading of the bacteria outside the digestive system. A significant problem for researchers who are trying to ascribe ExPEC transmission to food, people or the environment is to draw the distinction between colonization of ExPEC and infection. Food safety is an important challenge for public health both at the production stage and in the course of its processing and distribution. Examination of the genetic similarity of ExPEC strains will allow to determine their origin from different sources. Many levels of genotyping have been proposed in which the typing of strains, plasmids and genes is compared in order to obtain a more complete picture of this complex problem. The aim of our study was to characterize E. coli strains isolated from humans, animals and food for the presence of bacterial genes encoding virulence factors such as toxins, and iron acquisition systems (siderophores) in the context of an increasing spread of ExPEC infections.

High affinity to the epithelial lining of the airways makes Chlamydophila pneumoniae a common etiological agent of respiratory tract infections (RTI). It causes among others: pharyngitis, tracheitis, sinusitis, otitis media, bronchitis and bronchiolitis, and pneumonia. It is estimated that Chlamydophila pneumoniae infection is responsible for about 20% of lower respiratory tract infections. Chlamydophila pneumoniae infection may play an important role in the pathogenesis and course of bronchial asthma. The recent results indicate that Chlamydophila pneumoniae infection may be a factor responsible for 4-16% of COPD (Chronic obstructive pulmonary disease) exacerbations. A relationship of chlamydial infection with atherosclerosis raises huge interest. A connection of Chlamydophila pneumoniae infection with other non-communicable diseases such as lung cancer, arthritis, Alzheimer's disease, multiple sclerosis, sarcoidosis and erythema nodosum is also recognized, although the role of these bacteria has not been fully understood in any of the listed diseases (Adv Clin Exp Med 2014, 23, 1, 123-126).

No abstract

Human noroviruses, which belong to the enterovirus family, are one of the most common etiological agents of food-borne diseases. In recent years, intensive research has been carried out regarding the antiviral activity of plant metabolites that could be used for the preservation of fresh food, because they are safer for consumption when compared to synthetic chemicals. Plant preparations with proven antimicrobial activity differ in their chemical compositions, which significantly affects their biological activity. Our review aimed to present the results of research related to the characteristics, applicability, and mechanisms of the action of various plant-based preparations and metabolites against norovirus. New strategies to combat intestinal viruses are necessary, not only to ensure food safety and reduce infections in humans but also to lower the direct health costs associated with them.

The study confirmed asymptotic infection in 4% of women. In own research it was not possible to confirm cor-relation between the presence of Chlamydia trachomatis and the number of partners or the number of sexual intercourses.