Lactococcosis caused by Lactococcus garvieae is a bacterial infection affecting fish with a considerable economic impact. Recently, L. garvieae has established itself as an opportunistic pathogen in humans. The aim of the current study was to test classical and molecular-biological methods for the identification of L. garvieae and examine antimicrobial susceptibility and capsule production, an important virulence factor. Additionally, tests for differentiation from closely related species, as well as epidemiological typing, were performed. In a period of 18 years (2002–2019), 24 isolates presumptively identified as L. garvieae were collected from Oncorhynchus mykiss and Salmo salar fish obtained either from retail stores or fish farms. In order to confirm the species, optimized PCR-based protocols were used. As a result, 21 of the tested strains were proved to be L. garvieae (n = 21). The remaining three isolates were Lactococcus lactis, Streptococcus iniae, and Enterococcus faecalis. Epidemiological typing by randomly amplified polymorphic DNA was performed. Except for a single KG+ isolate, all other strains belonged to the European capsular serotype KG−. All L. garvieae isolates showed susceptibility to all tested antibiotics with the exception of clindamycin, which was a diagnostic sign. A thorough optimization of diagnostic methods is essential to determining the etiology of specific infections affecting the personnel at risk in fish farms, the food industry, or within the broader community.

Background: The use of plant-derived agents is a common approach in integrative care for respiratory conditions. However, the evidence of clinical trials has not yet been comprehensively presented. Aim: To summarize the antibacterial, antiviral, immunomodulatory, antioxidant, and expectorant properties of Echinacea spp., Pelargonium sidoides, Hedera helix, Thymus vulgaris, Althaea officinalis, Sambucus nigra, Zingiber officinale, and Curcuma longa, and to evaluate the evidence level from clinical trials (CTs) involving these agents in patients with respiratory tract infections (RTIs). Methods: We conducted a literature search using the PubMed database focusing on clinical studies of plant-derived agents in upper and lower RTIs. PRISMA-based reporting elements were used only as a guiding tool for comprehensibility of the literature search (Reporting Items for Systematic Reviews and Meta-Analyses guidelines). Results: A summary and structured overview of the properties of these most-cited plant-derived agents in the literature, in the context of RTIs, was provided. A total of 94 reports met the eligibility criteria and were included in our review. Of these, 66 reported randomized and placebo-controlled trials investigating the efficacy and tolerability of these adjuncts in patients with RTIs. The non-randomized and uncontrolled trials were 22. Sufficient evidence to be regarded as an appropriate treatment to reduce the severity and duration of RTIs was found for all discussed plant-derived agents. Robust evidence available was found for Echinacea spp., Pelargonium sidoides, Sambucus nigra, Curcuma longa and Zingiber officinale. Conclusions: Regarding other plant-derived agents reported in the traditional medicine for the treatment of RTIs, further research is needed to clarify the evidence gaps.

Helicobacter pylori poses a major threat to human health, primarily due to its tumorigenic potential and ability to cause tissue damage. Because of its strong association with gastric cancer and mucosa-associated lymphoid tissue lymphoma, H. pylori is classified as a class I carcinogen. Its eradication has become a challenge due to increasing antibiotic resistance rates. This implies the need to investigate nutritional factors for their anti- H. pylori effects. This study aimed to encompass data regarding anti-inflammatory, antibacterial, anti-adhesive, anti-ulcer, anti-urease and anti-cancer properties of seven non-antibiotic agents against H. pylori . We assessed articles in English using Science Direct, Scopus and Google Scholar, focusing mostly on recent publications. There are data pointing to the strong anti-adhesive action of cranberry, green tea and Arthrospira ( Spirulina ) spp. The anti-ulcer effect of green tea, Nigella sativa and microalgae was demonstrated in rat models. Cranberry, microalgae, honey and curcumin inhibit the urease activity of H. pylori. Propolis, green tea and curcumin interfere with the nuclear factor kappa B signalling pathway, while the last two as well as Arthrospira spp. inhibit cyclooxygenase-2. There are in vivo clinical trials indicating that cranberry, Nigella sativa , broccoli and curcumin can improve the success of eradication regimens, while honey showed a preventive effect. Additional trials are needed to determine the precise dose regimens and whether the natural or encapsulated product is more effective. Potential side effects and drug–drug interactions should be taken into account.

Background: Antibiotic resistance in Helicobacter pylori is steadily increasing, rendering the treatment of related gastroduodenal diseases increasingly difficult. Lefamulin is a new broad-spectrum antibacterial in the pleuromutilin class, acting by suppressing bacterial protein synthesis. It has the advantages of its unique “induced-fit” mechanism, a low frequency of spontaneous mutations, stepwise development of resistance, stability in acidic environments, and potential for additive or synergistic activity when combined with certain other antibiotics against various facultative anaerobes, including multidrug-resistant isolates. Methods: We investigated, for the first time to the best of our knowledge, the activity of lefamulin against 91 clinical H. pylori isolates from symptomatic adult patients using MIC test strips. Results: Overall, lefamulin MICs₅₀ and MICs₉₀ were 0.25 and 2 mg/L versus 4 and ≥256 mg/L for clarithromycin, and 0.75 and ≥32 mg/L, respectively, for levofloxacin. Lefamulin MICs₅₀ and MICs₉₀ were 0.5 mg/L and 4 mg/L against the 61 clarithromycin-resistant (MICs, >0.25 mg/L) isolates, 0.25 and 0.75 mg/L against the 40 levofloxacin-resistant (MICs, >1 mg/L) isolates, and 0.38 mg/L and 0.75 mg/L, respectively, against the 28 isolates resistant to both agents. Conclusions: Briefly, the new pleuromutilin antibiotic outperformed in vitro both clarithromycin and levofloxacin against H. pylori isolates. Its potential usefulness in treating H. pylori infections resistant to macrolides and fluoroquinolones, and especially those with dual resistance, justifies further investigation. However, some precautions should also be considered. The use of the novel antibiotic lefamulin may offer benefits for H. pylori eradication if our results are confirmed in subsequent studies, including clinical trials.

It is crucial to consider newer antibiotics with activity against anaerobes and Helicobacter pylori, given their healthcare importance, and the constantly growing antibiotic resistance/multidrug resistance, which complicates the therapy. The aim of this review was to emphasize certain recently approved or still-under-investigation antibiotics with potential benefits for treating Clostridioides difficile infections (CDIs), other anaerobic infections, and those caused by H. pylori, covering recent data from articles published primarily in 2020–2026. Given the limited number of antibiotics for treating CDI and fidaxomicin nonavailability in many countries, it is necessary to conduct more extensive laboratory and clinical studies of promising antibiotics such as ibezapolstat, delafloxacin, lascufloxacin, omadacycline, eravacycline, ridinilazole, and CRS3123. Against Bacteroides fragilis group species, delafloxacin and eravacycline showed good activity. Research on rifasutenizol for bacterial vaginosis, sarecycline and nadifloxacin for acne vulgaris and amixicile for periodontal diseases needs to be expanded. For H. pylori infection, delafloxacin, sitafloxacin, nemonoxacin, zoliflodacin, and rifasutenizol may improve the suboptimal success of most eradication regimens. However, more efforts, in coordination between medical, scientific, manufacturing, and government representatives, should ensure wider access to and research on the newer antibacterials. Establishing more research groups, careful examination of market issues, and additional approaches, such as nanomaterials, efflux pump inhibitors, phage therapy, and CRISPR-Cas systems, should be beneficial. Notwithstanding the difficulties, there are many opportunities to promote research on and potential use of newer antibiotics which show advantages over the older antibacterials, and to make them available to numerous countries and patients worldwide.

Pregnancy is a special period characterized by changes in the immune system as well as alteration of the microbiota predisposing to opportunistic infections, including tonsillopharyngitis. Streptococcus anginosus has numerous virulence factors, and it is associated with a variety of diseases. Being a part of the normal oral microbiota, it can be overlooked as a causative agent of infections in the oral cavity. A clinical case of a 29‐year‐old pregnant female who was allergic to penicillins and presented with recurrent tonsillopharyngitis has been described. Previous microbiological examinations have not shown any etiologic cause of patient’s symptoms. Two species were isolated. S. anginosus and S. oralis were identified using various methods, including nucleotide sequencing. S. anginosus was defined as the causative agent. Both were susceptible to all tested antibiotics. S. anginosus was positive for the duplicated sagA gene, encoding streptolysin S, an important factor of virulence. Based on clinical symptoms, paraclinical tests, immune competence, and characteristics of the strain, a multifactorial evaluation is required to determine whether an opportunist is a causative agent. Moreover, treatment of pregnant patients, particularly with antibiotics, is limited, which leads to therapeutic difficulties.