Posted on March 9, 2016
There are a plethora of infectious disease (ID) stories in the news that can have important medical consequences. John G. Bartlett, MD offers his observations on the top 10 most important infectious disease stories in 2015, as reported in Medscape Infectious Diseases:1
1. Antimicrobial Stewardship
A major concern in the ID world is the threat of a “post-antibiotic era” reflecting the loss of one medicine’s greatest achievement: the use of antibiotics to treat and prevent microbial infections. We were forewarned in 2004 with a publication entitled “Bad Bugs Need Drugs”2 and by 2015 it was considered a crisis by many organizations.
New regulations to be implemented by the Centers for Medicare and Medicaid Services (CMS) will affect nearly all antibiotic prescribers in the United States by requiring healthcare facilities to have an antibiotic stewardship program as a condition of participation. After extensive conversations and data generation on the consequences of antibiotic abuse, 2015 brought a program with enough clout to influence the majority of antibiotic prescribers (and healthcare facilities) in a fashion similar to the requirements for infection control.
2. New Antibiotics
One of the cogs in the wheel of antibiotic resistance is the scarcity of new antibiotics to deal with the tenet of “use it and lose it.” There is a financial risk associated with developing new antibiotics, especially since they are used for a short time, compared to drugs, like statins, that are taken for a lifetime.
From 1983 to 1987, a total of 16 new antibiotics were approved, compared with just one new agent from 2008 to 2012. However, from 2013 to 2015, six new antibiotics have been approved: three anti-staphylococcal drugs, two drugs for resistant gram-negative bacilli, and one agent for Clostridium difficile.
At least two findings were revealed with the Ebola situation:
The first report4 from Zaire in 1976 showed a high mortality rate, lack of treatment, and a high risk of transmission to healthcare providers. What was not recognized then but came out in 2015 was the existence of “sanctuary sites” with viral persistence (aqueous humor, semen, breastmilk, vaginal secretions), the potential for sexual transmission, and relapse after apparent recovery.
The world was caught by surprise – we need to be better prepared for earlier detection of unusual and potentially devastating infections, as seen with severe acute respiratory syndrome, swine flu, HIV, and anthrax (2001).5
4. Community-Acquired Pneumonia (CAP)
Conventional wisdom assumed that Streptococcus pneumoniae was the most common pathogen in CAP and “atypical agents” were the second most. However, a report6 published in 2015 by CDC (Centers for Disease Control and Prevention) concluded that S. pneumoniae accounted for only 5% of cases and the three atypicals (Chlamydia pneumoniae, Legionella, and Mycoplasma pneumoniae) accounted for only 4%. What are the other causative agents then? On a positive note, the study had strong data from the CMS database on CAP to assist with antibiotic prescribing.
5. Antiretroviral Therapy (ART) for HIV Infection
There were two schools of thought for starting ART: ART for all HIV infected patients regardless of CD4 count or viral load, or restrict ART to patients with CD4 counts < 350 cells/?L.
A large study was initiated (START trial7) – early findings showed a striking mortality benefit and reduction in complications by treating all HIV patients, regardless of CD4 count. Now WHO and mostly all HIV guidelines worldwide recommend ART for everyone with HIV infection.
6. Stool Transplant for C. difficile
Treatment of relapsing C. difficile infection with stool transplants actually began in 1980 but was not routinely used until the last 2 to 3 years. This practice represents the first important clinical application of the rapidly changing field of the human microbiome.
Results from 7,114 transplants show a response rate of 86%. Although still early, stool transplants could have broader implications with other medical conditions.
7. Hepatitis C Infection
It is rare that such a significant viral illness has been potentially defeated so quickly. It is estimated that there are 453,000 people in the United States infected with HCV and 130-175 million worldwide.8 Cure rates of over 95% have been seen with oral agents administered for 8 weeks.
The major controversy now is the cost of these medications, many patients with HCV infection cannot afford them. These drugs may be cost-effective by preventing the need for liver transplants and other medical comorbidities but who will pay the upfront cost.
8. C. difficile Infection (CDI)
CDI may be the highest priority for the CDC in 2016. In 2015 there were 354,000 cases of and 29,000 deaths from CDI, at a cost of about $1,200,000,000 in the United States.9
The polymerase chain reaction (PCR) test is the most sensitive test for detecting C. difficile but a positive test result needs clinical correlation before treatment is initiated, since hospitalized patients may be carriers and not infected. The United Kingdom reduced their CDI rates by 80%, using gene sequencing to alert infection control and controlling antibiotics.
9. Molecular Diagnostics in the field of ID
New data and tests are constantly being developed. Molecular testing can detect pathogens quicker and more accurately, be used in outbreaks to link cases and sources, and trace transmission routes of the carbapenemase-producing gram-negative rods at the National Institutes of Health Clinical Center, among many other applications.
It is thought that the microbiology lab of the future may resemble a chemistry lab. Although the potential uses for this technology are exciting, they are also expensive, there is not enough sensitivity data, not all pathogens can be identified, and pathogen vs contaminant is not possible with quantitation.
Medical management with antibiotics may work as well or better than surgery for acute appendicitis.10
Varicella-zoster has been implicated in giant-cell arteritis.11
Fusobacterium necrophorum may be an important possible cause of pharyngitis, found by Robert M. Centor and colleagues.12
I wonder what we will be talking about this time next year! Some may still be in the list, others may not. What about Lyme disease? Several comments to the article wondered why Lyme was left out since 300,000 cases were reported in 2015. How about Zika virus, surely that will still be a hot topic by the end of the year. Any other opinions?
What were the top infection prevention and control issues in your location?
John G. Bartlett MD. What were the top infectious disease stories in 2015? The year in infectious disease. December 11, 2015. Medscape Infectious Diseases.
Talbot GH, Bradley J, Edwards JE, Gilbert D, Scheld M, Bartlett JG; Antimicrobial Availability Task Force of the Infectious Diseases Society of America. Bad bugs need drugs: an update on the development pipeline from the Antimicrobial Availability Task Force of the Infectious Diseases Society of America. Clin Infect Dis. 2006;42:657-668.
Piot P. Ebola’s perfect storm. Science. 2014;345:1221.
Gates B. The next epidemic—lessons from Ebola. N Engl J Med. 2015;372:1381-1384.
Jain S, Self WH, Wunderink RG; CDC EPIC Study Team. Community-acquired pneumonia requiring hospitalization among US adults. N Engl J Med. 2015;373:415-427.
INSIGHT START Study Group, Lundgren JD, Babiker AG,etal. Initiation of antiretrovirals therapy in early asymptomatic HIV infection. N Engl J Med. 2015;373:795-807.
Mohamed AA, Elbedewy TA, El-Serafy M, El-Toukhy N, Ahmed W, Ali El Din Z. Hepatitis C virus: a global view. World J Hepatol. 2015;7:2676-2680.
Lessa FC, Winston LG, McDonald LC; Emerging Infections Program C. difficile Surveillance Team. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015;372:2369-2370.
Salminen P, Paajanen H, Rautio T, et al. Antibiotic therapy vs appendectomy for treatment of uncomplicated acute appendicitis: the APPAC randomized trial. JAMA. 2015;313:2340-2348.
Gilden D, Nagel M. Varicella zoster virus in temporal arteries of patients with giant cell arteritis. J Infect Dis. 2015:212 Suppl 1:S37-S39.
Centor RM, Atkinson TP, Ratliff AE, et al. The clinical presentation of Fusobacterium-positive and streptococcal- positive pharyngitis in a university health clinic: a cross-sectional study. Ann Intern Med. 2015;162:241-247.