1 Antibacterial medicines obtained by using the silver nanoparticles

There is persistent and constantly growing need for new antimicrobials which will be alternative to antibiotics. Wide usage of antibiotics has detected a number of negative factors. First, it is rapid appearance and spread of antibiotic-resistant microorganism strains. Second, it has been found out that antibiotics have a bad influence on microbiocoenosis. Moreover they lead to dysbacteriosis, disturb the intake and uptake of the nutrients, and weaken the immunity. Finally, antibiotics have no effect on viruses. It is possible that virus diseases are widespread nowadays just because of such unreasonably wide usage of antibiotics. According to the World Health Organization (WHO) the viral etiology diseases account for more than 75 % of the total number of infectious diseases and the percentage is growing. New dangerous infections appear such as atypical pneumonia, which is caused by coronavirus, bird flu, etc. As a rule the attempts of prompt production of virus vaccines are unsuccessful due to the ability of viruses to mutate and evolve rapidly. Mixed infections have become of great interest, e.g. in case when bacteria become more active in the organism weakened by some virus. The most illustrative case is HIV infection. The high contagiousness of viruses considerably increases the risk of epidemics and pandemics. Besides, rapid development of microbiology and virology, especially of diagnostics, enabled to determine an essential role of infectious agents (e.g