Superinfection

Superinfection occurs when an HIV-positive person is re-infected with a strain of HIV they do not already have. Cases of HIV superinfection have been definitively established, sometimes showing a loss of response to antiretroviral therapy after superinfection.1 2 3 Superinfection with wild-type virus can also occur when drug-resistant virus is already present.4

One study found no evidence of superinfection among 15 sexually active HIV-positive couples over at least two years. Another analysis of protease and reverse transcriptase sequences from 3155 San Francisco patients, most of whom were taking HIV therapy, failed to show any evidence of superinfection.5 6

Looking at newly infected individuals not on antiretroviral therapy, a California study reported an annual rate of superinfection of 5%, occurring between five and 13 months after the estimated date of initial infection.7 Superinfection sped disease progression: within six months, viral loads increased by an average of 1.6 log10 and CD4 cell counts decreased by an average of 132 cells/mm3. In another instance, superinfection led to the rapid onset of AIDS (within three-and-a-half years) and death (within six years) despite an initial good immune response.8

A 2005 report suggests that superinfection may be more common during the early stage of HIV disease when the immune response to the virus is not well developed.9

Looking at chronically infected gay male couples, risk factors for dual or superinfection included detectable viral load, presence of a concurrent sexually transmitted infection, and unprotected sex. The researchers hypothesised that chronically infected individuals might have a lower risk of superinfection because there are fewer host cells that would be vulnerable to a new viral strain.ref]

Superinfection with a different subtype leading to recombinant viruses has been documented10 as has superinfection leading to the existence of two circulating subtypes in an individual.11

References

  1. Jost S et al. A patient with HIV-1 superinfection. N Engl J Med 347: 731-736, 2002
  2. Booth C et al. Divergent pol sequences as markers of HIV-1 superinfection in a case of recurrent acute seroconversion illness. Fourth European Drug Resistance Workshop, Monte Carlo, abstract 101, 2006
  3. Smith DM et al. HIV drug resistance acquired through superinfection. AIDS 19: 1251-1256, 2005
  4. Koelsch KK et al. Clade B HIV-1 superinfection with wild-type virus after primary infection with drug-resistant clade B virus. AIDS, 17: F11-F16, 2003
  5. Chakraborty B et al. Evaluating HIV-1 superinfection in cell culture, the SCID-hu Thy/Liv model and HIV-infected individuals with high risk of re-exposure to the virus. Antivir Ther 7: S47, 2002
  6. Shafer RW et al. Failure to detect HIV-1 re-infection based on serial protease and reverse transcriptase sequences during 1239 patient years observation. Antivir Ther 7: S149, 2002
  7. Smith D et al. Incidence of HIV superinfection following primary infection. Eleventh Conference on Retroviruses and Opportunistic Infections, San Francisco, abstract 21, 2004
  8. Gottlieb G et al. HIV-1 superinfection in a rapid disease progressor: rapid replacement of the initial strain with the superinfecting virus by natural selection. Eleventh Conference on Retroviruses and Opportunistic Infections, San Francisco, abstract 454, 2004
  9. Grant R et al. High frequency of apparent HIV-1 superinfection in a seroconverter cohort. Twelfth Conference on Retroviruses and Opportunistic Infections, Boston, abstract 287, 2005
  10. Fang G et al. Recombination following superinfection by HIV-1. Antivir Ther 8: S202, 2003
  11. Yerly S et al. Prevalence of co- and super-infection in IVDUs. Antivir Ther 8: S203, 2003
Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap
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