According to the World Health Organization, one of the biggest health threats around the world is antibiotic-resistant bacteria. Every day people use antibiotics to prevent or fight back against infection, but as bacteria evolve and develop resistance, diseases such as pneumonia and tuberculosis are becoming harder to treat.
Researchers at the University of Notre Dame are working to combat this problem by looking to bacteriophages or phages. Phages are viruses that infect bacteria, similarly to how bacteria infect people, but bacteria have yet to develop resistance to these viruses.
In a study published in Nanoscale Advances, the researchers have shown the efficacy of a new nanoparticle-based system that mimics how phages attack and kill bacteria.
“Instead of chasing the next antibiotic, we want to create a system that can treat infection and is an option that bacteria can’t develop resistance to,” said Prakash Nallathamby, research assistant professor of aerospace and mechanical engineering and directing author of the study. “In our initial attempt, our team was able to kill several different types of clinically relevant bacteria with varying degrees of success.”
The phage-mimicking nanoparticle system consists of silver-coated gold nanoparticles distributed randomly on a silica core. Once created, the system was tested for its ability to kill four bacteria types that are known to have antibiotic-resistant strains: Corynebacterium striatum, Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus. These various bacteria cause a number of health issues including prosthetic device infections, sepsis, meningitis and blood infections.
Initial tests showed that the nanoparticle system was 50 percent to 90 percent effective in killing the bacteria strains for all but Pseudomonas aeruginosa, which was only 21 percent effective. However, when the researchers combined the nanoparticle system with peptides that also have antibacterial activity, the system was 100 percent effective at killing the bacteria.
“By incorporating a biological element, we were able to make the nanoparticles more effective in eliminating the bacteria in initial testing,” said Nallathamby. “Now, we are actively looking to partner with an organization that would advance this system to a clinical study.”
Infectious diseases have been a major cause of mortality historically. However, developments within medicine and public health during the 20th century helped to markedly reduce the burden associated with infectious diseases. In 1900, infectious diseases accounted for one-third of all deaths out of the top 10 leading causes of death.
On the contrary, in 2014, noncommunicable diseases such as cardiovascular illness and cancers accounted for the majority of deaths. Key medical breakthroughs, such as the discovery of penicillin, as well as improved sanitation played crucial roles in reducing the mortality associated with infections.
Fleming’s discovery of penicillin heralded in the “golden era” of antibiotic development, during which many new antibiotics were developed and introduced, causing many to believe that infectious diseases would soon be conquered. However, infectious diseases are again on the rise, especially those which can no longer be treated using the previously discovered antibiotics. Infectious pathogens are able to evolve and therefore over time, many have developed resistance to the currently-prescribed and newly-developed antibiotics.
In fact, antibiotic resistance has become a significant threat to the health of individuals at the global level. Methicillin-resistant Staphylococcus aureus (MRSA) kills nearly 50,000 individuals every year in the United States and Europe alone, with many more dying from it in other settings. Antibiotic-resistant diseases such as tuberculosis (TB) have significant impacts on developing countries. In 2013, there were approximately 480,000 cases of multidrug-resistant TB.
Since both developed and developing countries are equally affected by antibiotic-resistant infections, it is important to analyze antibiotic resistance development globally. Although it is difficult to get accurate estimates of drug resistance, it is predicted that antimicrobial-resistant infections will lead to nearly 10 million deaths per year by 2050 and a total GDP loss of $100.2 trillion by 2050 if appropriate actions are not taken.
Since infectious pathogens are constantly evolving and developing antibiotic resistance, it is essential to examine the key socioeconomic and political factors which contribute to the rise in the prevalence of antibiotic resistance in developing and developed nations. The purpose of this study was to conduct a qualitative literature review of the various factors contributing to the rise in antibiotic resistance globally.
This paper aims to highlight that there are distinct factors which play a role in increasing the prevalence of antibiotic resistance in developing and developed countries and argues that more measures need to be taken at international and national levels to improve the regulatory framework to slow the development of antibiotic resistance and augment research into novel therapies.
More information: Juliane Hopf et al. Phage-mimicking antibacterial core-shell nanoparticles, Nanoscale Advances (2019). DOI: 10.1039/C9NA00461K