Antibiotic Resistance Threats in the United States: Stepping Back from the Brink

Steven L. Solomon; Kristen B. Oliver

<< Previous article

Next article >>

Jun 15, 2014 Issue

Editorials

Antibiotic Resistance Threats in the United States: Stepping Back from the Brink

STEVEN L. SOLOMON, MD, and KRISTEN B. OLIVER, MEd, MPH, Centers for Disease Control and Prevention, Atlanta, Georgia

Am Fam Physician. 2014 Jun 15;89(12):938-941.

In a recently issued report, the Centers for Disease Control and Prevention (CDC) estimated the national burden of illnesses and deaths caused by the most common and most worrisome antibiotic-resistant pathogens.1 The report focused on 16 antimicrobial-resistant bacterial pathogens, as well as Candida infections, which together account for more than 2 million illnesses and at least 23,000 deaths every year in the United States.1 The report also included information on Clostridium difficile infections, which, like antibiotic resistance, are driven by antibiotic use. C. difficile causes more than 250,000 clinical infections annually and is associated with more than 14,000 deaths every year in the United States.1

In this report, the CDC categorized 18 pathogens (eTable A) into three groups (urgent, serious, and concerning) based on seven criteria: clinical impact, economic impact, incidence, 10-year projection of incidence, transmissibility, availability of effective antibiotics, and barriers to prevention.1 Three types of bacteria were included in the urgent category: carbapenem-resistant Enterobacteriaceae, drug-resistant Neisseria gonorrhoeae, and C. difficile. In the past, drug-resistant strains of Enterobacteriaceae and N. gonorrhoeae have shown a propensity to spread rapidly in the United States and around the world. Some strains of carbapenem-resistant Enterobacteriaceae are currently untreatable with available antibiotics, and the cephalosporin agents to which some gonococci are now showing emerging resistance are the last available drugs to effectively treat this infection. Thus, further spread of these strains constitutes a public health crisis. C. difficile infections already cause significant morbidity and mortality, and a recently emerging epidemic strain, BI/NAP1/027, appears to be more virulent.

Enlarge Print

eTable A

Antibiotic-Resistant Microorganism Threats

Microorganism	Notable information
Urgent
Clostridium difficile A1^,A2	Deaths related to C. difficile increased 400% between 2000 and 2007, in part because of a stronger strain
	Most infections are connected to receiving medical care
	Hand sanitizer does not kill C. difficile, and hand washing may not be sufficient
Carbapenem-resistant Enterobacteriaceae A3	Difficult to treat and, in some cases, untreatable
	Kills up to one-half of patients who get bloodstream infections
	Easily spreads antibiotic resistance to other bacteria
Drug-resistant Neisseria gonorrhoeae A4	Cases in the United States are more prevalent in the West and among men who have sex with men
	All patients treated for gonorrhea should routinely be offered condoms, referred for risk-reduction counseling, and retested for gonorrhea three months later
Serious
Multidrug-resistant Acinetobacter A5	Increasingly common in U.S. health care facilities; hard to treat
	Noted in U.S. service members wounded in Iraq and Afghanistan
Drug-resistant Campylobacter A6	Most cases are sporadic and not part of outbreaks
	Ciprofloxacin (Cipro) resistance to Campylobacter increased from 12% in 1997 to 24% in 2011
Fluconazole- (Diflucan-) resistant Candida (fungus)A7^–A9	Antifungal resistance in mucosal candidiasis varies by species
Extended spectrum β-lactamase–producing Enterobacteriaceae A10^,A11	Infections have become more common in recent years
	Once confined largely to hospitals, these bacteria, especially Escherichia coli, are increasingly common in community-acquired infections, particularly urinary tract infections
Vancomycin-resistant Enterococcus A12^–A14	Enterococci are the fifth most common cause of health care–associated infections
	Most likely to be found in urine and in wounds; may pose a risk for spreading in the outpatient setting
Multidrug-resistant Pseudomonas aeruginosa A15^,A16	About 8% of all health care–associated infections are caused by P. aeruginosa; about 13% of severe P. aeruginosa health care–associated infections are multidrug resistant
	P. aeruginosa may be isolated from outpatients with otitis, skin rash, and urinary tract infections
Drug-resistant non-typhoidal Salmonella A17^,A18	Estimated 1.2 million cases occur each year in the United States; most go unreported
	About 100,000 cases (8%) are caused by drug-resistant Salmonella
	Outbreaks occur each year; some involve multiple states and/or national distribution
Drug-resistant Salmonella serotype Typhi A19	Estimated 5,700 cases annually in the United States
	Most (up to 75%) are acquired during international travel
	Increasing resistance to antibiotics, especially fluoroquinolones
Drug-resistant Shigella A20	High-risk groups include children in day care centers (younger than five years) and their caregivers, men who have sex with men, international travelers, and persons in custodial institutions
	Increasing resistance to ciprofloxacin and azithromycin (Zithromax) is of particular concern
Methicillin-resistant Staphylococcus aureus A21^–A23	Although overall cases of invasive methicillin-resistant S. aureus are declining, the proportion of community-associated infections has increased
	Should be considered in the differential diagnosis of skin and soft tissue infections
Serious
Drug-resistant Streptococcus pneumoniae A24	Increasing threat of antibiotic resistance makes vaccination according to the Advisory
	Committee on Immunization Practices recommendations for children and adults more important
Drug-resistant tuberculosis A25^,A26	Number of tuberculosis cases is declining in the United States 63% of tuberculosis cases in the United States occur among foreign-born persons
	Proportion of primary multidrug-resistant tuberculosis cases occurring among foreign-born persons has been increasing
Concerning
Vancomycin-resistant S. aureus A27	Rare; 13 cases have been identified in the United States since 2002
	Severity of the consequences of S. aureus resistance to vancomycin require continued vigilance for this pathogen
Erythromycin-resistant group A Streptococcus A28	Penicillin remains the drug of choice, but the resistance to other drugs needed for patients allergic to penicillin is worrisome
	Of samples tested by the Centers for Disease Control and Prevention, 10% were erythromycin resistant and 3.4% were clindamycin resistant
Clindamycin-resistant group B Streptococcus A29	Neonates, pregnant women, and persons older than 65 years with underlying conditions are at highest risk
	Penicillin remains the drug of choice, but the resistance to other drugs needed for patients allergic to penicillin is worrisome

note: Additional information on the microorganisms in this table can be found in the Centers for Disease Control and Prevention's antibiotic threats report at http://www.cdc.gov/drugresistance/threat-report-2013/index.html (accessed March 27, 2014).

eTable A

Antibiotic-Resistant Microorganism Threats

Microorganism	Notable information
Urgent
Clostridium difficile A1^,A2	Deaths related to C. difficile increased 400% between 2000 and 2007, in part because of a stronger strain
	Most infections are connected to receiving medical care
	Hand sanitizer does not kill C. difficile, and hand washing may not be sufficient
Carbapenem-resistant Enterobacteriaceae A3	Difficult to treat and, in some cases, untreatable
	Kills up to one-half of patients who get bloodstream infections
	Easily spreads antibiotic resistance to other bacteria
Drug-resistant Neisseria gonorrhoeae A4	Cases in the United States are more prevalent in the West and among men who have sex with men
	All patients treated for gonorrhea should routinely be offered condoms, referred for risk-reduction counseling, and retested for gonorrhea three months later
Serious
Multidrug-resistant Acinetobacter A5	Increasingly common in U.S. health care facilities; hard to treat
	Noted in U.S. service members wounded in Iraq and Afghanistan
Drug-resistant Campylobacter A6	Most cases are sporadic and not part of outbreaks
	Ciprofloxacin (Cipro) resistance to Campylobacter increased from 12% in 1997 to 24% in 2011
Fluconazole- (Diflucan-) resistant Candida (fungus)A7^–A9	Antifungal resistance in mucosal candidiasis varies by species
Extended spectrum β-lactamase–producing Enterobacteriaceae A10^,A11	Infections have become more common in recent years
	Once confined largely to hospitals, these bacteria, especially Escherichia coli, are increasingly common in community-acquired infections, particularly urinary tract infections
Vancomycin-resistant Enterococcus A12^–A14	Enterococci are the fifth most common cause of health care–associated infections
	Most likely to be found in urine and in wounds; may pose a risk for spreading in the outpatient setting
Multidrug-resistant Pseudomonas aeruginosa A15^,A16	About 8% of all health care–associated infections are caused by P. aeruginosa; about 13% of severe P. aeruginosa health care–associated infections are multidrug resistant
	P. aeruginosa may be isolated from outpatients with otitis, skin rash, and urinary tract infections
Drug-resistant non-typhoidal Salmonella A17^,A18	Estimated 1.2 million cases occur each year in the United States; most go unreported
	About 100,000 cases (8%) are caused by drug-resistant Salmonella
	Outbreaks occur each year; some involve multiple states and/or national distribution
Drug-resistant Salmonella serotype Typhi A19	Estimated 5,700 cases annually in the United States
	Most (up to 75%) are acquired during international travel
	Increasing resistance to antibiotics, especially fluoroquinolones
Drug-resistant Shigella A20	High-risk groups include children in day care centers (younger than five years) and their caregivers, men who have sex with men, international travelers, and persons in custodial institutions
	Increasing resistance to ciprofloxacin and azithromycin (Zithromax) is of particular concern
Methicillin-resistant Staphylococcus aureus A21^–A23	Although overall cases of invasive methicillin-resistant S. aureus are declining, the proportion of community-associated infections has increased
	Should be considered in the differential diagnosis of skin and soft tissue infections
Serious
Drug-resistant Streptococcus pneumoniae A24	Increasing threat of antibiotic resistance makes vaccination according to the Advisory
	Committee on Immunization Practices recommendations for children and adults more important
Drug-resistant tuberculosis A25^,A26	Number of tuberculosis cases is declining in the United States 63% of tuberculosis cases in the United States occur among foreign-born persons
	Proportion of primary multidrug-resistant tuberculosis cases occurring among foreign-born persons has been increasing
Concerning
Vancomycin-resistant S. aureus A27	Rare; 13 cases have been identified in the United States since 2002
	Severity of the consequences of S. aureus resistance to vancomycin require continued vigilance for this pathogen
Erythromycin-resistant group A Streptococcus A28	Penicillin remains the drug of choice, but the resistance to other drugs needed for patients allergic to penicillin is worrisome
	Of samples tested by the Centers for Disease Control and Prevention, 10% were erythromycin resistant and 3.4% were clindamycin resistant
Clindamycin-resistant group B Streptococcus A29	Neonates, pregnant women, and persons older than 65 years with underlying conditions are at highest risk
	Penicillin remains the drug of choice, but the resistance to other drugs needed for patients allergic to penicillin is worrisome

Prevention strategies can be effective, but the major goals of the CDC report are to (1) increase awareness of the magnitude and looming risk of untreatable infections, and (2) spur concerted action, both to prevent further spread of resistant pathogens and to preserve the effectiveness of existing antibiotics. Thinking of antibiotics as a precious and diminishing resource has engendered the concept of antimicrobial stewardship, a defined set of practices designed to improve the appropriate use of antimicrobial agents.2 Table 1 lists steps to help implement resistance prevention strategies. Family physicians have an important role in combating antibiotic resistance through carefully prescribing antibiotics, educating patients, and identifying and reporting unexpected treatment failures and suspected resistance.

Enlarge Print

Table 1.

Steps to Combat Antimicrobial Resistance in Outpatient Settings

Steps	Suggestions for implementation
Improve antibiotic prescribing
Use current clinical guidelines to support rational and appropriate antibiotic prescribing	Share unremarkable findings during the examination (e.g., “no inflammation” or “normal breathing”), while acknowledging the patient is sick Determine the likelihood of a bacterial infection, especially for upper respiratory tract infections Provide a specific diagnosis (e.g., “viral bronchitis” vs. “virus”) Weigh benefits vs. harms of antibiotics Implement judicious prescribing strategies




Communicate with patients about when and why antibiotics may not be necessary	Explain that unnecessary antibiotic use can be harmful (e.g., adverse effects associated with antibiotic use, potential resistance development) Explain that treating viral infections with antibiotics does not work Explicitly plan treatment of symptoms by describing the expected normal course of the illness, and instruct patients to call or come back if symptoms persist or worsen; consider providing care packages with nonantibiotic therapies


Educate patients if an antibiotic is needed	Encourage adherence Discuss potential adverse effects
	Encourage adherence Discuss potential adverse effects
Create an office environment that promotes a reduction in antibiotic use	Start the process in the waiting room with videos, posters, and other materials Hang posters in examination rooms to display a commitment to not prescribe antibiotics for viral infections Involve office personnel in the reinforcement of the physician's messages


Prevent infections and the spread of resistant bacteria
Ensure that all patients get recommended vaccinations	Provide pneumococcal and influenza vaccines (to help avoid secondary bacterial infections), which are particularly important
Prevent cross-transmission	Counsel patients on how to avoid spreading or becoming infected with resistant pathogens in the community (e.g., methicillin-resistant Staphylococcus aureus) Follow recommendations for infection control in outpatient settings (http://www.cdc.gov/hai/settings/outpatient/outpatient-care-guidelines.html)

Monitor antibiotic-resistant infections
Report notifiable diseases	When appropriate, report to the health department any diseases caused by bacteria on the Centers for Disease Control and Prevention's list of urgent and serious pathogens (reporting requirements differ by U.S. state and Canadian province); antibiotic-resistant strains of some bacteria (e.g., methicillin-resistant S. aureus) are reportable in some states
Be alert for treatment failures	Consider the possibility of antibiotic resistance in cases of treatment failure; obtain laboratory confirmation and notify local public health authorities in cases of unusual or unexpected treatment failure

Table 1.

Steps to Combat Antimicrobial Resistance in Outpatient Settings

Steps	Suggestions for implementation
Improve antibiotic prescribing
Use current clinical guidelines to support rational and appropriate antibiotic prescribing	Share unremarkable findings during the examination (e.g., “no inflammation” or “normal breathing”), while acknowledging the patient is sick Determine the likelihood of a bacterial infection, especially for upper respiratory tract infections Provide a specific diagnosis (e.g., “viral bronchitis” vs. “virus”) Weigh benefits vs. harms of antibiotics Implement judicious prescribing strategies




Communicate with patients about when and why antibiotics may not be necessary	Explain that unnecessary antibiotic use can be harmful (e.g., adverse effects associated with antibiotic use, potential resistance development) Explain that treating viral infections with antibiotics does not work Explicitly plan treatment of symptoms by describing the expected normal course of the illness, and instruct patients to call or come back if symptoms persist or worsen; consider providing care packages with nonantibiotic therapies


Educate patients if an antibiotic is needed	Encourage adherence Discuss potential adverse effects
	Encourage adherence Discuss potential adverse effects
Create an office environment that promotes a reduction in antibiotic use	Start the process in the waiting room with videos, posters, and other materials Hang posters in examination rooms to display a commitment to not prescribe antibiotics for viral infections Involve office personnel in the reinforcement of the physician's messages


Prevent infections and the spread of resistant bacteria
Ensure that all patients get recommended vaccinations	Provide pneumococcal and influenza vaccines (to help avoid secondary bacterial infections), which are particularly important
Prevent cross-transmission	Counsel patients on how to avoid spreading or becoming infected with resistant pathogens in the community (e.g., methicillin-resistant Staphylococcus aureus) Follow recommendations for infection control in outpatient settings (http://www.cdc.gov/hai/settings/outpatient/outpatient-care-guidelines.html)

Monitor antibiotic-resistant infections
Report notifiable diseases	When appropriate, report to the health department any diseases caused by bacteria on the Centers for Disease Control and Prevention's list of urgent and serious pathogens (reporting requirements differ by U.S. state and Canadian province); antibiotic-resistant strains of some bacteria (e.g., methicillin-resistant S. aureus) are reportable in some states
Be alert for treatment failures	Consider the possibility of antibiotic resistance in cases of treatment failure; obtain laboratory confirmation and notify local public health authorities in cases of unusual or unexpected treatment failure

There are three main elements of preventing and controlling antibiotic resistance that are most applicable to outpatient practice. First, physicians must improve their antibiotic prescribing. Antibiotic use is the principal driver of antibacterial resistance. A considerable proportion of antibiotics in inpatient and outpatient settings are prescribed in cases when they are not needed or in which the choice of antibiotic, the dose, or the duration of therapy is inappropriate.3,4 Rates of outpatient antibiotic prescribing vary widely by region and state—a much greater variation than is likely explained by differences in patient populations or rates of bacterial diseases.5 It has been documented that inappropriate antibiotic prescribing, especially for viral upper respiratory tract infections, is common in ambulatory care.6 These illnesses are the most common reason for seeking medical attention in the United States and are associated with up to 75% of total antibiotic prescriptions each year.7 The causes of the overuse of antibiotics, which is a problem throughout the world, are complex and well described.8,9

The second main element is preventing infections and the spread of resistance. Preventing an infection eliminates the possibility that the infection could be drug resistant. Immunization and rigorous infection control, including hand washing, clearly reduce the likelihood of infection. On its website, the CDC provides information for patients on how to protect themselves from many types of infections, such as by ensuring safe food handling to prevent Salmonella and Campylobacter infections10 and by avoiding gonorrhea and other sexually transmitted infections.11 Counseling patients on how to avoid spreading or becoming infected with resistant pathogens in the community is an important role for physicians. For example, if an athlete is diagnosed with a methicillin-resistant Staphylococcus aureus infection, he or she should keep the wound properly covered, avoid whirlpools or therapy pools, shower after participation, clean uniforms and equipment after each use, and report infection to coaches and trainers.

The third main element is public health reporting. Gathering, analyzing, and disseminating information on resistant infections and the prevalence of resistant microorganisms is a critical strategy that informs clinical and public health decision making. A key component of detecting emerging and spreading resistance is identifying the cause of unexpected treatment failures. Patients who return with persistent or recurrent symptoms shortly after treatment should be retested by culture, and isolates should be submitted for antimicrobial susceptibility testing. Any case of unexplained treatment failure or a positive culture result after appropriate empiric treatment should be reported promptly to local or state health departments.12 Ultimately, public health surveillance is dependent on reporting by physicians and laboratories.

The nightmare scenario of the spread of pan-resistant bacteria is a real and frightening possibility. Cases of untreatable infections are already occurring. Preventing and controlling resistance requires the engagement of many different sectors of society. However, the physician's role in this effort is singularly important.12 As the threat becomes more urgent, the leadership of the medical community is the most critical factor to ensure a successful response.

The findings and conclusions of this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. government.

Author disclosure: No relevant financial affiliations.

Address correspondence to Steven L. Solomon, MD, at ssolomon@cdc.gov. Reprints are not available from the authors.

REFERENCES

show all references

1. Centers for Disease Control and Prevention. Antibiotic resistance threats in the United States, 2013. http://www.cdc.gov/drugresistance/threat-report-2013/index.html. Accessed March 27, 2014....

2. Dellit TH, Owens RC, McGowan JE Jr, et al. Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America guidelines for developing an institutional program to enhance antimicrobial stewardship. Clin Infect Dis. 2007;44(2):159–177.

3. Shapiro DJ, Hicks LA, Pavia AT, Hersh AL. Antibiotic prescribing for adults in ambulatory care in the USA, 2007–09. J Antimicrob Chemother. 2014;69(1):234–240.

4. Centers for Disease Control and Prevention (CDC). Office-related antibiotic prescribing for persons aged ≤14 years—United States, 1993–1994 to 2007–2008. MMWR Morb Mortal Wkly Rep. 2011;60(34):1153–1156.

5. Hicks LA, Taylor TH Jr, Hunkler RJ. U.S. outpatient prescribing, 2010. N Engl J Med. 2013;368(15):1461–1462.

6. Hersh AL, Jackson MA, Hicks LA; American Academy of Pediatrics Committee on Infectious Diseases. Principles of judicious antibiotic prescribing for upper respiratory tract infections in pediatrics. Pediatrics. 2013;132(6):1146–1154.

7. Gonzales R, Bartlett JG, Besser RE, et al. Principles of appropriate antibiotic use for treatment of acute respiratory tract infections in adults: background, specific aims, and methods. Ann Intern Med. 2001;134(6):479–486.

8. Srinivasan A, Fishman N. Antimicrobial stewardship 2012: science driving practice. Infect Control Hosp Epidemiol. 2012;33(4):319–321.

9. Roberts RM, Hicks LA. Appropriate antibiotic use: family physicians have the power of the pen. Am Fam Physician. 2012;86(9):810.

10. Centers for Disease Control and Prevention. Food safety. http://www.cdc.gov/foodsafety/. Accessed January 6, 2014.

11. Centers for Disease Control and Prevention. Gonorrhea. http://www.cdc.gov/std/gonorrhea/. Accessed January 6, 2014.

12. Bolan GA, Sparling PF, Wasserheit JN. The emerging threat of untreatable gonococcal infection. N Engl J Med. 2012;366(6):485–487.

REFERENCES

show all references

A1. Centers for Disease Control and Prevention. Vital signs: making health care safer. Stopping C. difficileinfections. March 2012. http://www.cdc.gov/VitalSigns/Hai/StoppingCdifficile/. Accessed March 27, 2014....

A2. Infectious Diseases Society of America. Infections by organism: Clostridium difficile. http://www.idsociety.org//organism/#Clostridiumdifficile. Accessed March 27, 2014.

A3. Centers for Disease Control and Prevention. Vital signs: making health care safer. Stop infections from lethal CRE germs now. March 2013. http://www.cdc.gov/vitalsigns/HAI/CRE/. Accessed March 27, 2014.

A4. Bolan GA, Sparling PF, Wasserheit JN. The emerging threat of untreatable gonococcal infection. N Engl J Med. 2012;366(6):485–487.

A5. Huang XZ, Chahine MA, Frye JG, et al. Molecular analysis of imipenem-resistant Acinetobacter baumannii isolated from US service members wounded in Iraq, 2003–2008. Epidemiol Infect. 2012;140(12)2302–2307.

A6. Centers for Disease Control and Prevention. National Center for Emerging and Zoonotic Infectious Diseases. Campylobacter. http://www.cdc.gov/nczved/divisions/dfbmd/diseases/campylobacter/technical.html. Accessed March 27, 2014.

A7. Niimi M, Firth NA, Cannon RD. Antifungal drug resistance of oral fungi. Odontology. 2010;98(1):15–25.

A8. Centers for Disease Control and Prevention. Fungal diseases. Candidiasis. http://www.cdc.gov/fungal/diseases/candidiasis/index.html. Accessed March 27, 2014.

A9. Cleveland AA, Farley MM, Harrison LH, et al. Changes in incidence and antifungal drug resistance in candidemia: results from population-based laboratory surveillance in Atlanta and Baltimore, 2008–2011. Clin Infect Dis. 2012;55(10):1352–1361.

A10. Hayakawa K, Gattu S, Marchaim D, et al. Epidemiology and risk factors for isolation of Escherichia coli producing CTX-M-type extended-spectrum β-lactamase in a large U.S. medical center. Antimicrob Agents Chemother. 2013;57(8):4010–4018.

A11. Doi Y, Park YS, Rivera JI, et al. Community-associated extended-spectrum β-lactamase-producing Escherichia coli infection in the United States. Clin Infect Dis. 2013;56(5):641–648.

A12. Grabsch EA, Burrell LJ, Padiglione A, O'Keeffe JM, Ballard S, Grayson ML. Risk of environmental and healthcare worker contamination with vancomycin-resistant enterococci during outpatient procedures and hemodialysis. Infect Control Hosp Epidemiol. 2006;27(3):287–293.

A13. Centers for Disease Control and Prevention. Healthcare-associated infections (HAIs). Vancomycin-resistant enterococii (VRE) in health-care settings. http://www.cdc.gov/HAI/organisms/vre/vre.html. Accessed March 27, 2014.

A14. Magill SS, Edwards JR, Bamberg W, et al. Emerging Infections Program Healthcare-Associated Infections and Antimicrobial Use Prevalence Survey Team. Multistate point-prevalence survey of health care–associated infections. N Engl J Med. 2014;370(13):1198–1208.

A15. Centers for Disease Control and Prevention. Healthcare-associated infections (HAIs). http://www.cdc.gov/HAI/organisms/Pseudomonas.html. Accessed March 27, 2014.

A16. Centers for Disease Control and Prevention. Healthy swimming/recreational water. Hot tub rash (Pseudomonas dermatitis/folliculitis). http://www.cdc.gov/healthywater/swimming/rwi/illnesses/hot-tub-rash.html. Accessed March 27, 2014.

A17. Centers for Disease Control and Prevention. Vital signs: making food safer to eat. Reducing contamination from the farm to the table. June 2011. http://www.cdc.gov/VitalSigns/FoodSafety/. Accessed March 27, 2014

A18. Centers for Disease Control and Prevention. Salmonella. http://www.cdc.gov/salmonella/. Accessed March 27, 2014.

A19. Centers for Disease Control and Prevention. National Center for Emerging and Zoonotic Infectious Diseases. Typhoid fever. http://www.cdc.gov/nczved/divisions/dfbmd/diseases/typhoid_fever/. Accessed March 27, 2014.

A20. Centers for Disease Control and Prevention. National Center for Emerging and Zoonotic Infectious Diseases. Shigellosis. http://www.cdc.gov/nczved/divisions/dfbmd/diseases/shigellosis/. Accessed March 27, 2014.

A21. Centers for Disease Control and Prevention. Methicillin-resistant Staphylococcus aureus (MRSA) infections. Treating MRSA skin and soft tissue infections in outpatient settings. http://www.cdc.gov/mrsa/community/clinicians/index.html. Accessed March 27, 2014.

A22. Dantes R, Mu Y, Belflower R, et al. Emerging Infections Program—Active Bacterial Core Surveillance MRSA Surveillance Investigators. National burden of invasive methicillin-resistant Staphylococcus aureus infections, United States, 2011. JAMA Intern Med. 2013;173(21)1970–1978.

A23. Infectious Diseases Society of America. Infections by organism: MRSA. http://www.idsociety.org//organism/#MRSA. Accessed March 27, 2014.

A24. Centers for Disease Control and Prevention. Vaccine recommendations of the ACIP. Pnuemococcal ACIP vaccine recommendations. http://www.cdc.gov/vaccines/hcp/acip-recs/vacc-specific/pneumo.html. Accessed March 27, 2014.

A25. Centers for Disease Control and Prevention. Tuberculosis (TB): fact sheet. Trends in tuberculosis, 2012. http://www.cdc.gov/tb/publications/factsheets/statistics/TBTrends.htm. Accessed March 27, 2014

A26. Infectious Diseases Society of America. Infections by organism: control of tuberculosis (TB). http://www.idsociety.org//organism/#ControlofTuberculosisTB. Accessed March 27, 2014.

A27. Centers for Disease Control and Prevention. Healthcare-associated infections (HAIs). http://www.cdc.gov/HAI/organisms/visa_vrsa/visa_vrsa.html. Accessed March 27, 2014.

A28. Centers for Disease Control and Prevention. Group A streptococcal (GAS) disease. http://www.cdc.gov/groupAstrep/clinicians.html. Accessed May 15, 2014.

A29. Centers for Disease Control and Prevention. Group B strep (GBS). http://www.cdc.gov/groupbstrep/about/index.html. Accessed March 27, 2014.

Copyright © 2014 by the American Academy of Family Physicians.
This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact afpserv@aafp.org for copyright questions and/or permission requests.