human herpesvirus 8 hhv 8 as an emerging pathogen relevance to semen donation n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation PowerPoint Presentation
Download Presentation
Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation

Loading in 2 Seconds...

play fullscreen
1 / 21

Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation - PowerPoint PPT Presentation


  • 141 Views
  • Uploaded on

Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation. Michael J. Cannon, Ph.D. Centers for Disease Control and Prevention. Issues Relevant to Emerging Pathogens and Donation Deferral Policies.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation' - rufus


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
human herpesvirus 8 hhv 8 as an emerging pathogen relevance to semen donation

Human Herpesvirus 8 (HHV-8) as an Emerging Pathogen: Relevance to Semen Donation

Michael J. Cannon, Ph.D.

Centers for Disease Control and Prevention

issues relevant to emerging pathogens and donation deferral policies
Issues Relevant to Emerging Pathogens and Donation Deferral Policies
  • Subsets of donors or potential donors with an elevated prevalence of the pathogen
  • Assays and assay development
  • Risk of transmission
  • Disease burden attributable to donation-related transmission
human herpesvirus 8 hhv 8
Human Herpesvirus 8 (HHV-8)
  • Discovered in 1994 (Chang et al., 1994)
  • Enveloped DNA virus
  • Closest human herpesvirus relative is Epstein-Barr virus
  • Strong evidence that HHV-8 has a causal role in:
    • Kaposi’s sarcoma (KS)
    • Primary effusion lymphomas
    • Multicentric Castleman’s disease
hhv 8 seroprevalence in selected populations vs blood donors us population
HHV-8 Seroprevalence in Selected Populations vs. Blood Donors/US Population

*Data not shown in article

issue 1 population subsets at risk
Issue 1—Population Subsets at Risk
  • HHV-8 is more common in HIV-negative MSM than in blood donors/US population.
  • There are no data on HHV-8 prevalence in MSM who are negative for HIV, HBV, and HCV.
  • However, many HIV-negative MSM are also negative for pathogens such as HBV and HCV (Tabet et al., 1998; Ndimbie et al., 1995).
  • Thus, testing for HIV, HBV, and HCV may not eliminate all MSM donors who are positive for HHV-8.
hhv 8 serologic assays
HHV-8 Serologic Assays
  • Latent antigens targeted
    • Major latent nuclear antigen encoded by open reading frame 73
  • Lytic antigens targeted
    • Virion glycoprotein encoded by open reading frame K8.1
    • Capsid protein encoded by open reading frame 65
  • Assay formats
    • Immunofluorescence assays (IFA) (Gao et al., 1996; Lennette et al., 1996; Smith et al., 1997; Whitby et al., 1998)
    • Enzyme immunoassays (EIA) (Simpson et al.,1996; Chatlynne et al., 1998; Pau et al., 1998)
    • Immunoblot assays (Zhu et al., 1999)
  • No FDA-approved assays
hhv 8 seroprevalence in blood donors
HHV-8 Seroprevalence in Blood Donors†

†Pellett et al., unpublished data

issue 2 screening tests
Issue 2—Screening Tests
  • PCR detection of HHV-8 DNA is not a sensitive testing method.
  • HHV-8 serological assays are:
    • Adequate for epidemiologic studies
    • Not sufficiently reliable for individual testing in low prevalence populations
  • HHV-8 serologic assays need to be improved and FDA approved.
hhv 8 transmission
HHV-8 Transmission
  • In the US, having multiple male homosexual partners carries the highest transmission risk.
  • Some transmission may occur via heterosexual sex and needle sharing.
  • In Africa, there is evidence that HHV-8 is transmitted via close, non-sexual contact.
  • Low HHV-8 seroprevalence in healthy persons suggests that transmission via close, non-sexual contact is rare in the US.
relationship between male sex partners and hhv 8 seroprevalence
Relationship between Male Sex Partners and HHV-8 Seroprevalence†

†Martin et al., 1998

issue 3 transmission risk
Issue 3—Transmission Risk
  • In the US the highest risk for HHV-8 transmission is through intimate contact with male homosexual sex partners.
  • However, HHV-8 is not commonly found in semen.
  • There are no studies measuring risk of HHV-8 transmission via semen donation.
  • HHV-8 transmission via donated semen is probably rare but the precise risk is unknown.
estimated annual risk of developing ks
Estimated Annual Risk of Developing KS
  • 1 in 1,000,000 in healthy persons (Biggar et al.,1984)
  • 1 in 80 in organ transplant recipients (Penn, 1997)
  • 1 in 50 in persons with HIV (Jones et al., 1999)
  • 1 in 20 in persons seropositive for both HIV and HHV-8 (Martin et al., 1998; Rezza et al., 1998; Jacobson et al., 2000).
issue 4 hhv 8 disease burden
Issue 4—HHV-8 Disease Burden
  • HHV-8 is uncommon in semen.
  • Even if a person becomes infected with HHV-8, additional factors (usually immunosuppression) are required for disease to occur.
  • Thus, the burden of disease associated with semen-donation acquired HHV-8 is probably very low.
  • However, the precise burden is unknown.
hhv 8 dichotomies
HHV-8 Dichotomies
  • HHV-8 is more common in HIV-negative MSM than in others.
  • However, HIV-negative MSM donors could not be screened for HHV-8 because there is no FDA-approved test.
  • HHV-8 is transmitted through intimate contact between male homosexual sex partners.
  • However, HHV-8 is rarely detected in semen.
  • The risk of disease caused by semen donation-acquired HHV-8 is probably very low.
  • However, the precise risk is unknown, and with blood donation, considerable dollars and effort are spent to lower the already low risks due to HIV, HCV, etc.
conclusions
Conclusions
  • HHV-8 is an example of an emerging pathogen that can be found in persons negative for HIV, HBV, and HCV.
  • Screening tests for emerging pathogens need to be developed and approved.
  • Precise risk of transmission needs to be estimated.
  • Disease burden attributable to the practice in question needs to be estimated.

If steps 2-4 are in place, a scale will exist upon which we can weigh the risks and benefits of different courses of action.

references
References
  • Chang et al., Science 1994, 266:1865-9
  • Simpson et al., Lancet 1996, 348:1133-8
  • Lennette et al., Lancet 1996, 348:858-61
  • Blackbourn et al., J Infect Dis 1997, 179:237-9
  • Martin et al., N Engl J Med 1998, 338:948-54
  • Cannon et al., N Engl J Med 2001, 344:637-643
      • Tabet et al., AIDS 1998, 12:2041-8
    • Ndimbie et al., Clin Diagn Lab Immunol 1995, 2:219-24
  • Gao et al., Nat Med 1996, 2:925-8
  • Smith et al., J Infect Dis 1997, 176:84-93
  • Whitby et al., J Natl Cancer Inst 1998, 90:395-7
references 2
References (2)
  • Chatlynne et al., Blood 1998, 92:53-58
  • Pau et al., J Clin Microbiol 1998, 36:1574-1577
  • Zhu et al., Virology 1999, 256:381-92
  • Pellett et al., J Clin Microbiol 1999, 37:1298-1301
  • Pauk et al., N Engl J Med 2000, 343:1369-77
  • Biggar et al., J Natl Cancer Inst 1984, 73:89-94
  • Penn, Transplantation 1997, 64:669-73
  • Jones et al., MMWR CDC Surveill Summ 1999, 48(SS-2):1-22
  • Rezza et al., Int J Cancer 1998, 77:361-5
  • Jacobson et al., J Infect Dis 2000, 181, 1940-9