Georgia epidemiology report, Vol. 18, no. 4 (Apr. 2002)

April 2002

volume 18 number 04

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. - Graphic Designer
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) 657-7517
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

No. cases

Shigellosis in Georgia, 2001:
Antimicrobial Resistance and Treatment
Currently, Georgia is experiencing an increase in Shigella infections with over 550 cases reported during August through December 2001 compared with 153 cases in the same time period in 2000. Ninety percent of cases during August through December were Shigella sonnei compared with 69% during the same time period in 2000. This surge in cases was initially seen in metro Atlanta and the Columbus Health District and was focused in African-American children.
In 2001, 734 cases of shigellosis were reported to the Georgia Division of Public Health (GDPH) (Figure 1). Among the 681 of known serotype, 606 (89%) were Shigella sonnei, 68 (10%) were S. flexneri, 4 (0.6%) were S. dysenteriae, and 3 (0.4%) were S. boydii. Their mean age was 14 years (range 0-95 years), and 45% of cases were among children under 6 years of age. Among these children, S. sonnei cases were even more predominant (95% of cases with a known serotype). Race was known for 59% of patients; of these, 27% were White, 72% were Black, and 1% were of other races. Fifty-seven per cent of isolates were from males.
Antimicrobial Resistance: Shigellosis is a notifiable disease in Georgia, and the Georgia Public Health Laboratory (GPHL) requests all stool or invasive isolates under the Emerging Infections Program. In 2000, the GPHL began testing all Shigella isolates for susceptibility by disc diffusion to 12 antimicrobial agents: ampicillin (AMP), amoxicillin with clavulanic acid (AUG), cephalothin (CEP), ceftriaxone (AXO), chloramphenicol (CHL), ciprofloxacin (CIP), gentamicin (GEN), nalidixic acid (NAL), streptomycin (STR), sulfisoxazole (SUL), tetracycline (TET), and trimethoprim/ sulfamethoxazole (SXT).
In 2001, 455 Shigella isolates were submitted to GPHL (406 S. sonnei, 47 S. flexneri, and 2 S. dysenteriae). Of 334 cases with known address, 86% were from the 20-county metropolitan Atlanta area.
Figure 1. Reported cases of shigellosis, Georgia, 19932001
2000 1800 1600 1400 1200 1000 800 600 400 200
0
1993 1994 1995 1996 1997 1998 1999 2000 2001

Percent

Figure 2. Antibiotic Resistance among all 455 Shigella isolates submitted to the GPHL in 2001
100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%
AUG AMP AXO CEP CHL CIP GEN NAL STR SUL TET S
Antibiotic Resistant Intermediate Susceptible

Percent

Figure 3. Antibiotic Resistance among the 406 Shigella sonnei isolates submitted to the GPHL in 2001
100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% AUG AMP AXO CEP CHL CIP GEN NAL STR SUL TET SX
Antibiotic Resistant Intermediate Susceptible

Figure 4. Antibiotic Resistance among the 47 Shigella flexneri isolates submitted to the

GPHL in 2001

flexneri isolates subm itted to the GPHL in 2001

100%

80%

Percent

60%

40%

20%

0% AUG AMP AXO CEP CHL CIP GEN NAL STR SUL TET
Antibiotic

Resistant Intermediate Susceptible

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Virtually all Shigella isolates (398/406 S. sonnei, 46/47 S. flexneri, and 2/2 S. dysenteriae) were resistant to at least one antimicrobial agent. Both Shigella dysenteriae isolates were resistant to ampicillin, streptomycin, and tetracycline. Resistance (intermediate or high-level) among all Shigella isolates combined was most prevalent to ampicillin (95%), cephalothin (63%), amoxicillin-clavulanic acid (55%), and streptomycin (48%) (Figure 2). The resistance patterns varied widely by serotype. S. sonnei isolates were resistant most frequently to ampicillin (96%), cephalothin (68%), amoxicillin-clavulanic acid (53%), and streptomycin (42%) (Figure 3). The resistance patterns among S. sonnei isolates from the 20-county metropolitan Atlanta area were similar to the patterns of S. sonnei isolates from the rest of the state. S. flexneri isolates were resistant most frequently to streptomycin (98%), tetracycline (92%), ampicillin (85%), amoxicillin-clavulanic acid (74%), chloramphenicol (68%), sulfisoxazole (55%), and trimethoprim/sulfamethoxazole (40%) (Figure 4).
Treatment: Shigella species cause diarrheal illness characterized by fever, malaise, and frequent small-volume watery stools that may progress to bloody, mucoid stools, associated with painful straining at defecation. Illness can be mild to severe, and is most often serious in young children. Rare complications include febrile seizures, rectal prolapse, proctitis, renal failure from hemolytic-uremic syndrome, severe dehydration and death.
Symptomatic infection with Shigella can occur after ingesting a small number of bacteria, making this the most infectious of the bacterial causes of diarrhea. Because of this, personto-person spread may occur particularly among family members, in daycare, in other institutional settings, and among men who have sex with men (MSM).
Whether to treat with antibiotics for shigellosis depends on severity of illness and other factors such as patient age. For severe disease such as dysentery (fever and painful, bloody stools), antibiotics are clearly indicated. Although antibiotic treatment is effective for shortening the duration of illness and eradicating the organism from stool, Shigella organisms can acquire antibiotic resistance rapidly. Therefore, for mild disease, the Centers for Disease Control and Prevention (CDC) recommends strategies other than antibiotics, such as attention to hand washing, to prevent spread of the organism. Of note, because shigellosis is highly infective, the Georgia Office of Regulatory Services requires 2 nega-

tive stool cultures before a child with shigellosis may return to daycare or school.
Antibiotic choice has become increasingly difficult with the evolution and spread of resistant strains. The choice of antibiotic is facilitated when local antibiotic susceptibility patterns of Shigella are known. Until recently, ampicillin and trimethoprim-sulfamethoxazole were considered to be drugs of choice for treating shigellosis. Given that Shigella in Georgia are likely to be resistant to ampicillin (95%), trimethoprim-sulfamethoxazole or other antibiotics are more likely to be effective. When antibiotics are needed, empiric treatment based on susceptibility of community strains may be useful. In Georgia children, shigellosis is overwhelmingly caused by S. sonnei, while in MSM S. flexneri strains are almost as common as S. sonnei.
When resistance to both first line drugs is widely prevalent, other options may be considered. Parenteral ceftriaxone may be used for treatment of adults or children, particularly if the patient is very ill. However, oral cephalosporins are considered suboptimal therapy, and first and second generation oral cephalosporins are ineffective clinically even when the organism is susceptible in vitro. For adults, fluoroquinolones such as ciprofloxacin are an effective empiric choice, but these drugs are generally avoided when treating children. Nalidixic acid provides an alternative choice for children, and is produced as syrup or pills, but may be less available than other antibiotics. In one study, azithromycin appeared to be effective among adults, but it has not been studied in children.
References: 1. Khan WA, Seas C, Dhar U, Salam MA, Bennish ML. Treatment of shigellosis: V. Comparison of azithromycin and ciprofloxacin. A double-blind, randomized, controlled trial. Annals of Internal Medicine 1997: 126:697-703. 2. Gupta A (Foodborne and Diarrheal Diseases Branch, CDC), Shigella Handout for ASTMH (Course Materials for American Society of Tropical Medicine and Hygiene Meeting, Nov. 10, 2001, Atlanta, GA). 3. American Academy of Pediatrics. Red Book 2000, pp. 510-512.
Authors: Stepy Thomas, M.S.P.H., Katie Arnold, M.D., Susan Lance-Parker, D.V.M., Ph.D., Sarah Ceaser, Steve Papagiotas, Jody Schweitzer

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The Georgia Epidemiology Report Epidemiology Branch Two Peachtree St., NW Atlanta, GA 30303-3186

PRESORTED STANDARD U.S. POSTAGE
PAID ATLANTA, GA PERMIT NO. 4528

April 2002

Volume 18 Number 04

Reported Cases of Selected Notifiable Diseases in Georgia Profile* for January 2002

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 - Primary Syphilis - Secondary Syphilis - Early Latent Syphilis - Other ** Syphilis - Congenital Tuberculosis

Total Reported forJan 2002
2002 3
2904 1 1 2
1621 9 11 25 0 0 2 0 0 0 36 39 6 12 47 26 0 8

Previous 3 Months Total

Ending in Jan

2000

2001 2002

107

103

70

6037

7598

7871

33

33

17

12

5

7

335

263

102

4325

4603

4545

29

36

36

62

138

110

62

127

93

2

3

1

0

0

0

22

17

16

1

2

1

18

3

3

0

0

0

356

317

284

50

82

377

25

25

19

72

54

49

130

122

164

176

179

128

1

6

0

164

195

162

Previous 12 Months Total

Ending in Jan

2000

2001 2002

701

619

606

30657

29898

32186

165

188

149

43

43

46

1344

1203

863

21334

19306

18156

86

86

104

443

417

874

239

376

419

6

11

10

0

0

0

78

51

50

5

3

7

61

43

23

0

1

0

1954

1711

1657

271

341

752

135

127

86

277

279

279

638

545

638

757

733

751

14

25

14

638

695

550

* 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: 03/01-02/02 Five Years Ago: 02/97-01/98 Cumulative: 07/81-02/02

Total Cases Reported* <13yrs >=13yrs Total

2

1871

1873

4

1585

1589

210

24381 24591

Percent Female

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

25.3

34.4

8.4

2.6

12.3

1.9

40.3

21.3

40.9

20.1

4.7

20.2

1.2

13.0

17.4

47.8

17.8

5.5

13.3

1.9

13.7

Race Distribution (%) White Black Other

18.8 76.3

4.9

24.3 72.7

3.0

34.5 63.1

2.3

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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