An Insidious and Chilling Menace

For long it had been thought that each bacterial species was either a pathogen causing a specific disease or a non harmful commensal species, and that each bacterial species evolved on its own.

Quote from Joseph R. Dalovision (IDSA President): Infectious diseases physicians are alarmed by the prospect that effective antibiotics may not be available to treat seriously ill patients in the near future. There simply aren’t enough new drugs in the pharmaceutical pipeline to keep pace with drug-resistant bacterial infections, so-called “super-bugs”.

It is now recognized that both types of bacteria can exchange genes, particularly those conferring resistance to antibiotics, commensal bacteria serving as a reservoir of such genes for pathogenic microbes. The dynamic of resistance is now clearly demonstrated to be often based on a two-step process consisting:

• first in the emergence of resistance in the commensal flora during antibiotic treatments and
• second in its dissemination to pathogenic bacteria.

The rise in bacterial resistance together with the decline in antibiotic discovery may pave the way for major epidemics.

Thanks to the discovery of new antibiotics and their use for the last 60 years, the threat posed by many infectious diseases has been substantially reduced. It is widely accepted that antibiotics have been the most important contributing factor to the major rise in life expectancy observed in the 20th century, however this rise is now seriously jeopardized by two recent developments: the emergence and spread of microbes resistant to one, and often several antibiotics on the one hand, and the decline in discovery and marketing of new antibiotics on the other hand.

The bacterial infections which principally contribute to human diseases are also those in which emerging antimicrobial resistance is most striking. They include many pathologies such as diarrheal diseases, respiratory tract infections, meningitis, sexually transmitted infections, and nosocomial infections. Some important examples of microbes which have become resistant to many available antibiotics include the penicillin-resistant Streptococcus pneumoniae, vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), multi-resistant salmonella and Escherichia coli, and multi-resistant gram-negative bacteria that cause nosocomial infections. Some of the bacteria that cause these types of infection are even pan-resistant to antibiotics, leaving very few therapeutic options open, and even sometimes none.

The consequences are severe. Infections caused by resistant microbes fail to respond to treatment, resulting in prolonged illness and a greater risk of death. Treatment failures also lead to longer periods of infection, which increase the dissemination of resistant bacteria, thus increasing the probability of inter-individual transmission and exposing the general population to the risk of contracting an infection caused by a resistant strain.

Proportion of E coli invasive isolates with resistance to fluoroquinolones in 2006

Emergence of resistance and its dissemination are two key processes that Da Volterra has chosen to fight in the intestinal tract, using novel and proprietary approaches.