Georgia epidemiology report, Vol. 16, no. 4 (Apr. 2000)

April 2000

volume 16 number 04

Division of Public Health
http://health.state.ga.us

The Georgia Epidemiology Report is a publication of the Epidemiology Section of the Epidemiology and Health Information Branch, Division of Public Health, Georgia Department of Human Resources

THIS IS A TWO PART REPORT. THE FIRST ISSUE WILL CONTAIN
GENERAL INFORMATION ON POST-EXPOSURE PROPHYLAXIS AND
HEPATITIS B POSTEXPOSURE. THE SECOND PART
WILL CONTAIN INFORMATION ON
HIV POST EXPOSURE PROPHYLAXIS.
Director Kathleen E. Toomey, M.D., M.P.H.
Epidemiology and Health Information Branch
Acting Director Kathleen E. Toomey, M.D., M.P.H.
Acting State Epidemiologist Paul A. Blake, M.D., M.P.H.
Epidemiology Section Chief
Paul A. Blake, M.D., M.P.H.
Public Health Advisor Mel Ralston
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

POSTEXPOSURE PROPHYLAXIS FOR
NEEDLESTICKS AND OTHER
OCCUPATIONAL EXPOSURES (Part 1)
General information
What is post-exposure prophylaxis (PEP) and what diseases should be considered? Post-exposure prophylaxis is an attempt to prevent the transmission of a disease after an
exposure has occurred. Receiving treatment following certain exposures to either human immunodeficiency virus (HIV) or hepatitis B virus (HBV) may prevent subsequent infection. Although no prophylactic regimen currently exists for hepatitis C virus (HCV), post-exposure testing is routinely performed following exposure to HCV.
What types of exposures require evaluation for prophylaxis? Blood or bloody fluid, semen, vaginal secretions, cerebrospinal fluid, synovial fluid, serous
fluid, or tissue from persons with HBV or HIV are considered infectious. HBV or HIV may be transmitted to a health care worker (HCW) when an exposure to infectious material consists of a percutaneous injury (e.g., a needlestick or cut with a sharp object), contact of mucous membrane or nonintact skin (e.g., when exposed skin is chapped, abraded, or afflicted with dermatitis), or contact with intact skin when the duration of contact is prolonged (i.e., several minutes or more) or involves an extensive area. Direct contact with concentrated HIV, as may occur in a laboratory or, also requires evaluation for PEP. HBV may be also be transmitted from the saliva of an infected person; therefore, bites may require HBV prophylaxis. HIV, on the other hand, has only rarely been reported as a result of a bite. Post-exposure prophylaxis and follow-up for HIV should be considered if a bite resulted in exposure to blood. Percutaneous exposure to HCV infected blood may result in a hepatitis C infection. The risk of infection from other occupational exposures is not well defined. Currently, there is no effective PEP for HCV.
What is the likelihood of becoming infected following a percutaneous exposure? The risk of HBV transmission following a percutaneous exposure depends on both the
hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) status of the source. As HBsAg is present in all potentially infectious sources, this is the test used when determining the need for PEP. HBeAg correlates with viral replication and higher levels of circulating virus in HBsAg-positive individuals. The risk of HBV transmission to a HCW after a percutaneous exposure to HBeAg-positive blood is approximately 30%. The average risk of HIV transmission following a percutaneous exposure to infected blood is 0.3%. The risk of HCV transmission following percutaneous exposure is approximately 3.5% 10%.
What is the first thing that should be done following an exposure? Wounds or skin should be immediately washed with soap and water; mucous membranes
should be flushed with water.
Who should be notified after an exposure has occurred? All occupational exposures should be immediately reported to ones supervisor. Other work-
related offices, which may need to be involved, include occupational health and/or infection control. A persons primary care provider should also be immediately informed so that PEP can be arranged, if needed.
Georgia Department of Human Resources Division of Public Health, Epidemiology Section Epidemiology & Health Information Branch Two Peachtree St., N.W., Atlanta, GA 30303 - 3186 Phone: (404) 657-2588 Fax: (404) 657-2586

When should prophylaxis be started? If PEP for HBV is to be given (see HEPATITIS B POST-EXPO-
SURE PROPHYLAXIS), it should be initiated as soon after the exposure as possible. When indicated, hepatitis B immune globulin (HBIG) should be given within 24 hours of exposure. It is unclear if there is any benefit to administering HBIG beyond seven days after exposure. If both hepatitis B vaccine and HBIG are to be administered, they can be given simultaneously. Alternatively, the hepatitis B vaccine may be administered later, but within 7 days of exposure. The hepatitis B vaccine (given in the deltoid for adults) and HBIG should always be administered at separate sites. If HIV prophylaxis is indicated (see HIV POST-EXPOSURE PROPHYLAXIS), it should be started within 1-3 hours of exposure. Animal studies suggest that PEP for HIV is probably not effective after 2436 hours, however, this time period has not been established for humans. PEP may be considered even after 1-2 weeks if the exposure is felt to carry a high risk for transmission. If HIV PEP is to be given, but there is uncertainty as to the appropriate drug regimen, it is probably better to start zidovudine (ZDV) and lamivudine (3TC) immediately while treatments are being discussed.
When should follow-up testing be performed and what tests are needed?
Baseline testing for individuals exposed to HBV will depend on their immune status (see HEPATITIS B POST-EXPOSURE PROPHYLAXIS). Hepatitis B infection may be detected in susceptible individuals as early as two months following an exposure. Circulating HBsAg is evidence of hepatitis B infection. Those persons who are vaccinated as

part of PEP should be tested for an antibody response (i.e., immunity to hepatitis B). HBIG, which is included in most PEP regimens, may interfere with the tests to determine immunity. Therefore, if HBIG is given, testing for immunity should be delayed for at least 6 months following HBIG administration. If immunity does not develop, testing for hepatitis B infection (i.e., HBsAg) should continue for up to 12 months following an exposure. Health care workers with an HIV exposure should have follow-up testing regardless of whether they receive PEP. HIV antibody testing should be performed at baseline and then for at least 6 months after the exposure (e.g., at 6 weeks, 12 weeks, and 6 months). Persons receiving HIV PEP should also be followed for adverse reactions to the medications (see INFORMATION ON DRUGS COMMONLY USED FOR HIV PEP and ADDITIONAL IMPORTANT INFORMATION FOR HIV-EXPOSED HCWs). Persons exposed to HCV should have baseline testing for antibody to hepatitis C virus (anti-HCV) and hepatic enzymes (i.e., ALT activity). Follow-up testing for anti-HCV should be done at 4-6 months along with ALT activity. Testing for HCV RNA by reverse transcriptase polymerase chain reaction (RT-PCR) may be performed at 4-6 weeks for an earlier diagnosis of HCV.
How effective is PEP? In one large randomized trial, a PEP regimen which included HBIG
was 75% effective in preventing acute hepatitis in susceptible persons following a percutaneous exposure to HBV. In one retrospective case-control study, the use of ZDV following percutaneous exposure to HIV reduced the risk of infection by 81%.

Hepatitis B Post-Exposure Prophylaxis

Vaccination and antibody response status of exposed person

HbsAg* positive

Treatment when source is HBsAg negative

Source not tested or status unknown

Unvaccinated

HBIG x 1 dose plus initiate Initiate HB vaccine 3-dose HB vaccine series series

Initiate HB vaccine series

Previously vaccinated:

Known responder

No treatment

No treatment

No treatment

Known non-responder to primary vaccine series

HBIG x 1 dose plus reinitiate 3-dose of HB vaccine series

If known high-risk source, may treat as if source is HBsAg positive

Known non-responder after twice receiving full vaccine series

HBIG x 2 doses

No treatment

If known high-risk source, may treat as if source is HBsAg positive

Antibody response unknown

Test exposed for anti-HBs 1. If adequate antibody
titer no treatment required 2. If inadequate antibody titer give HBIG x 1 dose plus one dose of HB vaccine**

No treatment

Test exposed for anti-HBs 1. If adequate antibody titer
no treatment required 2. If inadequate antibody titer
give one dose of HB
vaccine**

* HBsAg = Hepatitis B surface antigen One dose of hepatitis B immune globulin (HBIG) = 0.06 ml/kg intramuscular. The first dose of hepatitis B vaccine (HB vaccine) can be given simultaneously with HBIG or within 7 days of exposure. Vaccine should be administered in the deltoid for adults at a site separate from HBIG. A known responder is defined as a person who 1-6 months after completion of the vaccine series has a serum level of antibodies to hepatitis B surface antigen (anti-HBs) > 10 milliInternational Units (mIU)/ml. The first dose of HBIG (0.06 mg/kg) should be given immediately after exposure and the second dose should be administered one month later. An adequate antibody titer is defined as an anti-HBs level > 10 mIU/ml. ** Persons receiving a vaccine booster dose should be evaluated for antibody response. Those who also receive HBIG should be tested for anti-HBs
when passively-acquired antibodies from HBIG are no longer detectable (i.e., six months following HBIG administration). If HBIG is not given, anti-
HBs testing can be done 1-2 months after the vaccine booster dose. If the anti-HBs titer is inadequate (< 10 mIU/ml), two additional doses of HB
vaccine should be administered at the appropriate times to complete a 3-dose revaccination series.
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According to the Advisory Committee on Immunization Practice any HCW who performs tasks involving contact with blood, blood-contaminated body fluids, other body fluids, or sharps should receive the hepatitis B vaccine. In the United States, a recombinant hepatitis B vaccine is currently available. The vaccine should be given in a series of three intramuscular doses at 0, 1, and 6 months (adults should receive injections in the deltoid). Ninety percent of adults who receive the full series develop an adequate antibody response. Field trials have shown that the vaccine is 80%-95% effective in preventing infection or clinical hepatitis. Since HCWs may have occupational exposures which require PEP, it is recommended that they be tested following vaccination to document an adequate antibody response. Post-vaccination testing should be done between one to two months after completion of the vaccine series. An adequate response to vaccination is defined as having a serum level of antibodies to hepatitis B surface antigen (anti-HBs)> 10 milliInternational Units (mIU)/ml. Those HCWs who do not have an adequate response to primary vaccine series should undergo a second three-dose vaccine series. Post-vaccination testing should again be performed for individuals requiring revaccination.

Antibody levels will gradually decline in vaccinated persons over time. In fact, up to 60% of the vaccine responders will lose their detectable antibodies over a period of 12 years. Despite this decline in the level of antibody, persons with a previous adequate response to vaccination will continue to be immune to HBV. Therefore, booster doses of vaccine are not considered necessary for individuals who had an adequate response to vaccination.
Individuals who test positive for HBsAg are infected with HBV. HBV can be transmitted to others through exposure to infected bodily fluids. Blood and serous fluids typically have the highest concentration of hepatitis B virus, while lower concentrations can be found in saliva and semen. PEP should be considered for susceptible HCWs following a percutaneous (needle stick, laceration, or bite) or permucosal (ocular or mucous membrane) exposure to fluids which are known or suspected to be infected with HBV. The following table outlines the different PEP treatment options based on the vaccination status of the HCW (and his/her response to vaccination) and the hepatitis B status of the source.
References and resources to follow in next issue.

MENINGOCOCCAL VACCINE RECOMMENDATIONS FOR COLLEGE STUDENTS

During 1998 and 1999, all 50 states participated in a Centers for Disease Control and Prevention (CDC) project for enhanced meningococcal surveillance in United States college students. This was the first opportunity to gather national information on meningococcal disease in college students, because information on college attendance had not been routinely reported previously.
Between September 1998 and June 1999, 88 cases of meningococcal disease were identified among college students. These cases represent about 3% of the total cases of meningococcal disease that occur each year in the United States. Thirty nine cases (44%) occurred among the 2.27 million freshman students entering college each year. The median age of cases was 19 years (range 18-37) and half the cases were male. Among the 69 (81%) students for which serogroup information was available, 49% were serogroup C, 24% serogroup B and 20% serogroup Y. Eight (9%) students died. Most importantly, the rate of meningococcal disease among undergraduate college students was 0.7/100,000, lower than the rate among 18-23 year old non-college students (1.1/ 100,000). However, rates were elevated among subgroups of college students. Among the approximately 500,280 first-time freshmen who live in dormitories the rate of meningococcal disease was 5.4/100,000, higher than any age group in the population other than children less than 2 years of age, but lower than the threshold of 10/100,000 recommended for initiating meningococcal vaccination campaigns. Freshman status (OR=2.4, p=0.095) and dormitory dwelling (OR = 5.2, p=0.08) were independent risk factors for meningococcal disease in a multivariate model.
These finding suggest that while college students as a group are not at higher risk for meningococcal disease, subgroups of college students may be at higher risk.
A recently published, smaller study of Maryland College Students (Harrison L, et al., Risk of Meningococcal Infection in College Students. JAMA 1999; 281: 1906-1910) had similar findings, and stated: From a public health perspective, it may be difficult to justify a national immunization policy focused on college students. The incidence in college students does not appear to be substantially higher than that in the general population of the same age . . . Furthermore, the public health impact of such a program would most likely not be major. A high vaccine coverage in young, generally healthy adults can be difficult to achieve. Importantly, the current available quadrivalent purified polysaccharide vaccine has a negligible effect on nasopharyngeal carriage

of N. meningitidis, indicating that this vaccine would not offer herd immunity. The available vaccine also does not cover serogroup B.
On the other hand, there are arguments in favor of immunizing college students. Meningococcal infection is a devastating illness that occurs in the prime of life and is frequently fatal. Most infections are preventable with a vaccine that is safe and efficacious, and an increasing proportion of cases are caused by serogroups included in the vaccine. From an individual standpoint, the vaccine is inexpensive relative to the cost of higher education . . .The routine immunization of incoming college freshmen could potentially prevent outbreaks and sporadic disease in college students, as well as prevent the phenomenal disruption that occurs on college campuses as a result of meningococcal outbreaks.
In October, 1999, the Advisory Committee for Immunization Practices (ACIP) met to consider guidelines for use of the meningococcal vaccine, which have not specifically addressed college students in the past. Because the American College Health Association (ACHA) has recommended that college students receive the meningococcal vaccine, there has been confusion in the medical community as to which guidelines should be followed. The studies cited above provided data that allowed the ACIP to make an informed decision. The revised ACIP guidelines specify that:
Individuals who provide medical care to [college] freshmen, particularly those who live in or plan to live in dormitories or residence halls, should provide information about meningococcal disease and the benefits of vaccination to these students and their parents. Immunization should be provided or made easily available to those freshmen who wish to reduce their risk of meningococcal disease. Current data suggests that risk among non-freshmen college students is not elevated compared to the general population; however, vaccine can be provided to non-freshman undergraduates (traditionally less than 25 years of age) who wish to reduce their risk of meningococcal disease.
The Georgia Division of Public Health is working with CDC in collaborating with the American College Health Association to implement a case-control study of meningococcal disease among college students. The purpose of the case-control study is to confirm these preliminary findings.
This issue underscores the value of continuous active, population and laboratory-based surveillance to monitor the evolving epidemiology of meningococcal disease. These data will be crucial for developing a cogent national vaccine policy when new and more effective vaccines become available for N. meningitidis.
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The Georgia Epidemiology Report Epidemiology and Health Information Branch Two Peachtree St., NW Atlanta, GA 30303-3186

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

April 2000

Volume 16 Number 04

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

SelectedSelected Notifiable Notifiable Diseases Diseases Campylobacteriosis Chlamydia genital infection 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 for January
2000 21 1618 15 2 85 1161 13 18 2 0 0 9 0 2 0 81 16 1 6 20 12 0 11

Previous 3 Months Total

Ending in January

1998

1999

2000

202

161

101

4761

6191

5746

21

40

33

5

10

12

255

302

331

5364

4626

4326

17

24

29

191

189

62

70

45

31

3

0

1

2

0

0

34

19

21

1

1

0

2

5

6

0

0

0

301

393

343

403

148

47

36

38

39

72

75

70

254

199

185

246

207

208

1

8

2

146

154

165

Previous 12 Months Total

Ending in January

1998

1999

2000

783

767

691

9389 24947 31057

81

159

168

38

83

43

911

1251

1338

11346 20197 21535

44

66

86

802

866

444

245

196

189

6

8

4

9

4

0

115

87

77

9

2

4

15

38

48

0

0

0

1375

1858

1934

1202

1090

268

148

125

139

319

240

276

1016

792

710

1017

813

741

23

19

17

669

624

643

* 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.

AIDS Profile Update

Report Period Report Period

Total Cases Reported *

Percent Female

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

Latest 12 Months: 2/99-01/00 Five Years Ago: 2/94 - 01/95 Cumulative: 7/81 - 01/00

1645 2344 21539

26.4

32.1

13.3

3

17.4

1.5

32.7

18.8

44.1

22.7

6

13.7

2.1

11.4

16.1

49.7

18.8

5.8

13

1.9

10.8

MSM - Men having sex with men

IDU - Injection drug users

HS

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

- 4-

Race Distribution (%) White Black Other

19

78.8

2.2

33.1 65.4

1.5

36.8 61.1

2.1

- Heterosexual