Georgia epidemiology report, Vol. 16, no. 10 (Oct. 2000)

October 2000

volume 16 number 10

Division of Public Health http://health.state.ga.us
Kathleen E. Toomey, M.D., M.P.H. Director
State Health Officer
Epidemiology Branch http://health.state.ga.us/epi
Paul A. Blake, M.D., M.P.H. Director
State Epidemiologist
Mel Ralston Public Health Advisor
Georgia Epidemiology Report Editorial Board
Carol A. Hoban, M.S., M.P.H. - Editor Kathryn E. Arnold, M.D. Paul A. Blake, M.D., M.P.H.
Susan Lance-Parker, D.V.M., Ph.D. Kathleen E. Toomey, M.D., M.P.H.
Angela Alexander - Mailing List Jimmy Clanton, Jr. - Graphics
Georgia Department of Human Resources
Division of Public Health Epidemiology Branch Two Peachtree St., N.W. Atlanta, GA 30303-3186 Phone: (404) 657-2588 Fax: (404) 657-2608
Please send comments to: Gaepinfo@dhr.state.ga.us
The Georgia Epidemiology Report is a publication of the Epidemiology Branch,
Division of Public Health, Georgia Department of Human Resources

Recognition of a multidrug-resistant strain of
Salmonella Typhimurium in Georgia
Background
A multidrug-resistant strain of Salmonella Typhimurium known as Definitive Phage Type 104 (DT104) was first recognized in the United Kingdom in 1984 (1). This strain is resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulfonamides (Su), and tetracycline (T) (ACSSuT pattern). Use of antimicrobial drugs as growth promoters in feed animals may have contributed to the emergence of this highly resistant strain (2). According to the Centers for Disease Control and Prevention, transmission of S. Typhimurium DT104 through food probably occurs through a complicated route that may include wild animals, animal feed, farm animals, slaughterhouses, processing and distribution networks, retail outlets, and the consumer (2).
S. Typhimurium DT104 has been recognized in the United States (U.S.) (3) and has been responsible for several outbreaks. A 1996 outbreak in school children may have been caused by milk consumption or contact with a kitten or turtle. A 1997 outbreak in Vermont occurred among ill dairy cattle and humans who drank unpasteurized milk. Homemade cheese produced using unpasteurized milk has been implicated in outbreaks in California and Washington. DT104 has been isolated from a variety of animals in the U.S., such as pigs, sheep, cats, dogs, birds and others (4).
Screening S. Typhimurium for resistance to chloramphenicol has been reported to be a reliable method to screen for the multi-drug resistant DT104 strain. We conducted an investigation to characterize S. Typhimurium strains in Georgia, and to determine if DT104 is present.
Methods
S. Typhimurium (ST) is the most commonly identified Salmonella serotype in Georgia (GA). Four hundred six ST isolates were identified through active surveillance of Georgia laboratories during a period of 14 months (February 1998 - March 1999). The Georgia Public Health Laboratory (GaPHL) tested these 406 isolates for resistance to ampicillin (A), chloramphenicol (C), streptomycin (S), sulfamethoxazole (Su), and tetracycline (T). In addition, all ST isolates submitted between October 1998 and March 1999 (n=159) were examined by PFGE using the PulseNet protocol for molecular subtyping of foodborne bacterial pathogens, and analyzed using Molecular Analyst Fingerprinting Plus software. Those with an ASSu or ASSuT pattern of resistance were tested for resistance to an additional antimicrobial agent, kanamycin.
Results
Ninety-six (24%) of the 406 isolates were chloramphenicol (C)- resistant, and 99% of the C-resistant isolates were ACSSuT-resistant. ACSSuT resistance was more frequent in isolates from blood (59%) than in those from stool (21%) [RR 5.4, 95% C.I. (2.3 - 13.2)]. In addition, 32 (8%) of the 406 isolates were resistant to ASSuT, but not to chloramphenicol. PFGE of the 159 October 1998 - March 1999 isolates identified 56 patterns and 20 clusters (Dice correlation >90%), with clusters falling into 3 major groups:
Group 1 (56 isolates) was ACSSuT-resistant; 54 of these closely resembled DT104 by
PFGE. One isolate from Group 1 was resistant only to ASSuT.
Group 2 (15 isolates) was markedly different from the other strains by PFGE.
Twelve were ASSuT-resistant, while the other 3 were only ASSu-resistant. Further testing of these isolates showed that 14 of the 15 were also resistant to kanamycin.
Group 3 (88 isolates) includes all other PFGE patterns.

Conclusions
A large proportion of Salmonella ser. Typhimurium (ST) in Georgia is now caused by the ACSSuT strain. Fifty-four (34%) of 159 ST that were subjected to both antimicrobial resistance testing and PFGE closely resembled the DT104 strain. This multi-drug resistant clone appears to be associated with more serious disease. It was disproportionately common in patients with documented ST bacteremia. Due to the fact that patients with invasive disease require antimicrobial therapy, the high prevalence of DT104 has clinical implications.
In addition, a new strain of ST that is resistant to ASSuT but not to chloramphenicol was identified and accounted for 8% (12/159) of ST in Georgia. Using chloramphenicol to screen isolates for multi-drug resistant DT104 would have missed this C-sensitive, multi-drug resistant clone. The clinical and epidemiologic significance of the ASSuT clone and the risk factors associated with the development of antimicrobial-resistant ST are not well understood.
Discussion
Salmonellosis is a bacterial infection that causes diarrhea, fever, and abdominal cramps 12 to 72 hours after infection. The illness lasts approximately 4 to 7 days. Using antibiotics for uncomplicated Salmonella enterocolitis is generally not recommended; such treatment has no clinical benefit, may lead to resistant strains or more severe infections, and will not necessarily prevent ongoing carriage of salmonella (5). Most infected persons recover without treatment. However, antibiotic therapy is generally recommended for immunocompromised patients, those with severe symptoms or invasive (bloodstream) infections, or those ill enough to require hospitalization (6). The choice of antibiotics for treatment is complicated by antibiotic resistance (7). A fluoroquinolone is often recommended empirically for adults, but concerns exist for use of these drugs in children (8). First-line drugs for children include amoxicillin, TMP/SMX, and cefotaxime (8). The high prevalence of ST DT104 and ST with the ASSuT resistance pattern (42% of ST strains from clinical sources in Georgia) may influence the empirical choice of drugs and the need for antimicrobial resistance testing of ST isolates.
Many Salmonella infections can be prevented by proper food handling practices. Salmonella frequently contaminate foods of animal origin, so it is important not to eat raw or undercooked eggs, poultry, or meat, and not to drink unpasteurized milk or juice. Produce should be washed thoroughly. Uncooked meats should be kept separate from produce and other foods to prevent cross-contamination. Hands, cutting boards, counters, and utensils should be washed thoroughly with soap and hot water after handling uncooked foods. Hands should be washed before handling any food, between handling different food items, and after contact with human or animal feces. Persons with salmonellosis should not prepare food or drinks for others until they have a negative stool culture. Turtles, iguanas, and other reptiles are particularly likely to shed salmonellosis in their feces, so careful hand washing after handling reptiles is important (7).

We encourage physicians to obtain stool cultures from persons with suspected infectious gastrointestinal illnesses. To identify Salmonella or other bacteria as the cause of illness, a laboratory must isolate the organism. After isolation of Salmonella, the serotype and antimicrobial sensitivities can be determined (7). Currently, the Georgia Division of Public Health is working with laboratories statewide to ensure that every Salmonella isolate is submitted for serotyping, a free service of the GaPHL. If indicated, the GaPHL can genetically subtype the strains to determine if they are related to other strains. Serotyping and subtyping have proved to be extremely helpful in identifying and investigating outbreaks. If you have Salmonella specimens that are not currently being sent to GaPHL, please contact Marsha Ray, 404-329-7990, to arrange for serotyping.
References
1. Threlfall EJ, Frost JA, Ward LR, Rowe B. Increasing spectrum of resistance in multiresistant Salmonella Typhimurium. Lancet 1996; 347: 1053-4.
2. Centers for Disease Control and Prevention. Multi-drug resistant Salmonella Serotype TyphimuriumUnited States, 1996. Morbidity and Mortality Weekly Report. 1997; 46:308-310
3. Davis M, Hancock D, Besser T, et al. Changes in antimicrobial resistance among Salmonella enterica Serovar Typhimurium isolates from humans and cattle in the Northwestern United States, 1982-1997. Emerging Infectious Disease Journal, Vol 5, No. 6, Nov-Dec 1999.
4. Akkina J, Hogue A, Angulo F, Johnson R et al. Epidemiologic aspects, control, and importance of multiple-drug resistant Salmonella Typhimurium DT104 in the United States. Journal of the American Veterinary Medical Association, Vol 214, No. 6, March 15, 1999
5. Chin, J. Control of Communicable Diseases Manual. Report of the American Public Health Association. 17th ed. Washington, DC; 2000.
6. Gilbert D, Moellering R, and Sande M. The Sanford Guide to Antimicrobial Therapy, 28th ed. Vienna, VA: Antimicrobial Therapy, Inc.; 1998.
7. h t t p : / / w w w . c d c . g o v / n c i d o d / d b m d / d i s e a s e i n f o / salmonellosis_g.htm
8. Siberry, G and Iannone R. The Johns Hopkins Hospital Harriet Lane Handbook, 15th ed. St. Louis, MO: Mosby, Inc.; 2000.
9. Oosterom J. Epidemiological studies and proposed preventive measures in the fight against human salmonellosis. International Journal of Food Microbiology 1991; 12:41-51.

Written by Laura Gilbert, M.P.H., Susan Lance-Parker, D.V.M., Ph.D., Paul Blake, M.D., M.P.H., Bob Manning, and Barbara Wallace.

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Highlights from the Georgia Cancer Data Report 2000

Cancer is a major health problem in Georgia
Cancer is the second leading cause of death in Georgia, accounting for 22% of all deaths between 1994-1998.
More than 32,900 Georgians will develop cancer in 2000, and 13,700 will die.
Lung, colorectal, breast and prostate cancer account for 54% of cancer deaths in Georgia.
Lung cancer is the leading cause of cancer death among Georgians and accounts for 30% of all cancer deaths.
Lung cancer mortality rates among Georgia females have doubled since 1980.
Blacks in Georgia are 27% more likely than whites to die of cancer.
Much of the burden of death and disability from cancer is preventable
Tobacco use accounts for at least 30% of all cancer deaths and about 87% of all lung cancer cases.
Between 1992-1998, smoking rates in Georgia increased 5% per year among females and 4% per year among males.
In 1999, 19% of middle school students reported current use of tobacco.
About one-third of cancer deaths are related to diet, nutrition, and lack of physical activity.

In 1998, only 21% of Georgia adults consumed 5 or more fruits and vegetables per day.
Less than one-third of Georgia adults are physically active on a regular basis.
Some cancers can be detected early when treatment is most effective
For 1996-1998, only 55% of Georgia females aged 50 and older had a mammogram and clinical breast examination within the previous year.
For 1996-1998, 90% of Georgia females aged 18 and older had a Pap test in the past 3 years.
In 1997, 52% of males and 45% of females in Georgia had ever had sigmoidoscopy.
The Georgia Cancer Data Report 2000 was written to assist health professionals, volunteers and staff of cancer control organizations, community groups, and others who are working to reduce the burden of cancer throughout Georgia. The Report includes information about cancer mortality, cancer incidence, and cancer risk behaviors in Georgia. The data can be used to plan interventions, coordinate effective collaborations, and develop funding applications.
Copies of the Georgia Cancer Data Report 2000 can be obtained by sending your request to:
Rana Bayakly 2 Peachtree Street, NW 16.283 Atlanta, Georgia 30303-3142 or visit our web site at http://www.health.state.ga.us/programs/cancer/index.shtml.

Leading Causes of Death in Georgia, 1994-1998

Stroke 7%
Un in t en t io n al injury 5%
COPD 4%
Pneumonia & influenza 4%
Diabetes 2%

Other 26%
Heart Disease 29%

Cancer 22%

Lung/bronchus 30%
Colon & rectum 9% Breast 2% Prostate 7%
Other cancers 46%

Respiratory Syntycial Virus (RSV) Surveillance
The Georgia Division of Public Health is conducting surveillance for Respiratory Syntycial Virus at 11 sentinel sites throughout the state. Check our web page for information about RSV and follow weekly reports from these sites. http://www.health.state.ga.us/epi/
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The Georgia Epidemiology Report Epidemiology Branch Two Peachtree St., NW Atlanta, GA 30303-3186

Bulk Rate U.S. Postage
Paid Atlanta, Ga Permit No. 4528

October 2000

Volume 16 Number 10

Reported Cases of Selected Notifiable Diseases in Georgia Profile* for July 2000

Selected Notifiable Diseases
Campylobacteriosis Chlamydia trachomatis Cryptosporidiosis E. coli O157:H7 Giardiasis Gonorrhea Haemophilus influenzae (invasive) Hepatitis A (acute) Hepatitis B (acute) Legionellosis Lyme Disease Meningococcal Disease (invasive) Mumps Pertussis Rubella Salmonellosis Shigellosis Syphilis - Congenital Syphilis - Early Latent Syphilis - Other** Syphilis - Primary Syphilis - Secondary Tuberculosis

Total Reported for July 2000
2000 76
2692 27 17 128
1810 2 28 24 0 0 2 0 5 0
229 26 0 37 58 7 22 34

Previous 3 Months Total

Ending in July

1998

1999 2000

251

226

221

5459

10832

7733

31

25

40

45

15

27

291

293

314

5014

6769

4915

13

27

14

177

122

79

47

56

71

6

0

2

1

0

0

17

19

11

0

1

0

18

17

11

0

0

0

465

586

541

446

74

67

7

2

4

211

128

120

233

181

150

26

37

30

50

58

66

179

209

160

Previous 12 Months Total

Ending in July

1998

1999

2000

950

896

703

19493

31462

32735

132

203

174

66

70

67

1199

1406

1506

18954

22906

22171

57

92

81

908

790

370

291

197

287

10

5

11

13

1

0

110

85

67

2

2

5

32

49

67

0

0

0

1615

2280

2135

1556

704

312

19

18

20

1034

831

674

1063

845

791

154

144

155

305

268

336

687

696

691

* The cumulative numbers in the above table reflect the date the disease was first diagnosed rather than the date the report was received at the state office, and therefore are subject to change over time due to late reporting. The 3 month delay in the disease profile for a given month is designed to minimize any changes that may occur. This method of summarizing data is expected to provide a better overall measure of disease trends and patterns in Georgia.
** Other syphilis includes latent (unknown duration), late latent, late with symptomatic manifestations, and neurosyphilis.

Report Period
Latest 12 Months: 8/99 - 7/00 Five Years Ago: 8/94 - 7/95 Cumulative: 7/81 - 7/00

Total Cases Reported*

Percent Female

AIDS Profile Update
Risk Group Distribution (%) MSM IDU MSM&IDU HS Blood

Unknown

1261

26.6

29.7

11.7

2.8

14.7

1.6

39.6

2411

18.5

47.2

21.3

6.2

14.4

1.8

9.1

22100

16.4

49.2

18.6

5.7

12.9

1.9

11.6

MSM - Men having sex with men

IDU - Injection drug users

HS - Heterosexual

* Case totals are accumulated by date of report to the Epidemiology Section

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Race Distribution (%) White Black Other

20.1 76.6

3.3

36

61.9

2

36.4 61.5

2.1