The Year in Infectious Diseases: The Top Three Stories in 2014
This is a review of 10 developments in the field of infectious diseases in 2014 that are likely to have a substantial impact on medical practice. They are listed in no particular order, but the top three (Ebola, hepatitis C, and antibiotic resistance) are the probable headliners. Comments will be brief, yet attempt to address issues that may not be patently obvious.
The leading story in the lay press regarding infectious diseases translated to a direct impact on the entire healthcare system. One of the most important contributions was from Professor Peter Piot, who discovered the virus 35 years ago and recently reviewed its status from a global public health perspective. He notes that this epidemic started 38 years ago in West Africa, where there were continuous civil wars, a very poor healthcare delivery system, a great shortage of healthcare workers, and religious and burial practices that promoted infection. Combined with a viral pathogen that had a transmission rate (R0) of nearly 2 (meaning that 2 cases became 4, then 8, then 16, then 32, etc), this was the "perfect storm" that could not happen in a developed country.
Some people were of the opinion that the optimal approach would be to pool resources from developed countries that are donated to the World Health Organization (WHO) for control of the disease in West Africa. Furthermore, the 21-day quarantine commonly suggested for healthcare workers coming from the epidemic area lacks scientific validity and seems unduly cruel to such true heroes as the volunteers with Doctors Without Borders.
The problem of antibiotic resistance has been festering for decades and has finally reached the crisis point, according to the Infectious Diseases Society of America (IDSA), the Centers for Disease Control and Prevention (CDC), WHO, the European Union, and President Obama. The CDC has identified a broad menu of worrisome pathogens that are becoming resistant, and many pathogens that may soon be untreatable.
The highest-ranking pathogens (considered "urgent") are carbapenemase-producing Enterobacteriaceae, Neisseria gonorrhoeae, and Clostridium difficile. The latter is possibly confusing, because the consensus is that the drug of choice is oral vancomycin and, to my knowledge, no vancomycin-resistant strain has been reported among more than 10,000 isolates. A possible explanation is resistance of C difficile to fluoroquinolones, which appeared to drive the epidemic of the NAP1 strain in much of Europe and North America in the mid-1990s.
This antibiotic crisis reflects the combined impact of overuse of antibiotics ("use it and lose it") and the failed market response. Major pharmaceutical suppliers have largely abandoned the antibiotic development field owing to very poor economic return ("We are not in the business to go out of business").
The major development for a coordinated multifaceted response is the President's Council of Advisors on Science and Technology (PCAST) proposal to President Obama that was previously summarized for Medscape. In essence, this combines efforts for a massive US/global surveillance system combined with gene sequencing, incentives for pharmaceutical development, and emphasis on antibiotic stewardship as a condition of payment by the Centers for Medicare & Medicaid Services (CMS).[5,6]
For providers, the immediate message is to conserve antibiotics using established methods. These include:
• Short antibiotic courses;
• Procalcitonin levels to guide decisions about starting and stopping antibiotics;
• Waiting-room announcements that antibiotics are given only according to guidelines;
• Use of molecular diagnostics to improve rapid pathogen detection;
• Automatic stop orders;
• Gene sequencing to inform infection control; and
• Efforts to prevent nosocomial infections with the four infections that account for the largest numbers in cost, by dollars and deaths: central line bacteremia, ventilator-associated pneumonia, Clostridium difficile infection, and surgical-site infection (primarily colon resection and vaginal hysterectomy).
The glorious accomplishments in this field are nicely summarized as "the arc of a medical triumph" by Chung and Baumert, highlighting the short, 25-year span from the discovery of hepatitis C virus (HCV) to treatment that now achieves cure in more than 95% of patients with a single oral pill taken once daily for 8-12 weeks. This remarkable story reflects the precedent of success in treating AIDS; the identification of susceptible viral targets; a pharmaceutical industry that responded rapidly; a trial network that was already established; and the work of the US Food and Drug Administration (FDA), a regulatory system that actively facilitated drug development.
HCV afflicts 2.7-3.9 million people in the United States, and about 250 million worldwide; it is currently a common cause of cirrhosis and hepatocellular cancer and is an indication for liver transplant. The role of primary care is to detect cases with specific emphasis on the baby boomers (born 1945-1965) who account for more than 75% of US cases. The concern is the cost of treatment, which is $74,000 or more per case, leading to controversy between advocates who want to treat everyone vs payers, who generally want to restrict support to those with fibrosis scores of F3/F4.
Medscape Infectious Diseases © 2014 WebMD, LLC
Cite this: John G. Bartlett. The 2014 Hit Parade: Infectious Disease Stories of the Year - Medscape - Dec 09, 2014.