The discovery of mRNA by Sydney Brenner dates back to 1961, but the in vivo expression of mRNA was successful only in 1990, which initiated the development of vaccines based on this molecule. During Sars-CoV-2 pandemy the interest in the use of nucleic acids in the production of drugs and vaccines has increased significantly. The success of mRNA vaccines against Sars-CoV-2 has particularly empowered the pharmaceutical industry to create newer and newer generation products based on RNA modification that could help not only in Covid-2019, but also in the prevention and treatment of other infectious diseases. RNA has a very high potential - it can be used in highly personalized therapies, furthermore the production of mRNA is cheaper, faster than the current therapeutics and the process of mRNA making is more flexible due to the great ease of producing mRNA in the process of transcription. Modifying of the structure of ribonucleic acid and the methods of its delivery leads to the creation of newer and newer vaccines. In this review, we present the potential of RNA molecule in producing vaccines, types of RNA vaccines, strategies of RNA delivery and review of existing RNA-based vaccines.

This review underlines the significant role of early diagnosis and treatment of hearing impairment due to bacterial meningitis (BM) in children. BM is a life-threatening neurological condition mostly caused by <i>Streptococcus pneumoniae</i>, <i>Neisseria meningitides</i>, or <i>Haemophilus influenzae</i>. Hearing loss is the most commonly reported neurological complication of BM; inflammation can damage the inner ear, leading to sensorineural hearing loss or complete deafness. Factors favoring neurological complications, including hearing impairment, are low age, immaturity of the immune system, poor health, anaemia, leukocytosis, and hypoglycemia. To avoid serious complications, quick intervention is necessary – administration of antibiotic in combination with dexamethasone. It is also important to conduct regular audiological tests to monitor hearing, not only immediately after BM, but also in the long term. Otoacoustic emissions (OAEs) and auditory brainstem responses (ABRs) are useful tools, and some researchers also recommend tympanometry. CTs and MRIs are important to visualize the condition of the inner ear after BM, paving the way for qualification for implantation and for pre-operative planning. The best results of implantation come from patients without ossification, whose period of deafness was short, where electrodes were inserted deeply, and who did not have neurological complications after BM. Early implantation is the best option as it promotes proper speech development and allows the child to adapt to their environment.