Wednesday, February 2, 2011


Part One

1. Sexually Transmitted Infections

1.1 Reproductive Tract Infections

Reproductive Tract Infections/RTIs are infections which affect the reproductive tract in males and Females.

RTIs can be caused by organisms which are normally present in/near the reproductive tract or they can be introduced by outside, (Sexual route or medical procedures).
RTIs are basically of three types,

1. Iatrogenic infections: Infections caused by medical procedures in women like unclean delivery, unsafe abortion, IUCD insertion. Example: Staphylococcus aureus, Pseudomonas

2. Endogenous Infections: Infections caused by overgrowth of organisms in the reproductive tract of women in conditions like diabetes, immune deficiency.  Example: Candida albicans and bacterial vaginosis

3. Sexually Transmitted Infections (STI): Infections caused by unprotected sexual act with multiple partners or with partner or spouse who has multiple partners.

STIs are basically of two types

Viral (Difficult to treat)
* Ulcerative: Genital herpes
* Non ulcerative: HIV, Genital Warts, HPV

Non viral (Treatable & curable)
* Ulcerative: Syphilis, Chancroid
* Non ulcerative: Gonorrhoea, Chlamydia, Trichomoniasis

1.2 STI increases vulnerability to HIV

A randomized control trial was done to evaluate the impact of improved STI case management at primary health care level on the incidence of HIV infection in a rural region of Tanzania. HIV incidence, or numbers of new HIV infections, was compared in intervention communities and control communities where no intervention was conducted.

The improved STI services were designed to be feasible for resource-poor settings and were integrated with the Tanzanian primary health care system. Patients in the intervention community were treated according to WHO recommended syndromic STI case management guidelines. As part of the intervention, an STD reference clinic was established in each community, staffs were trained, a regular supply of effective STI drugs was provided, regular supervisory visits to health facilities were conducted, and health education about STIs was delivered.

Over a two-year period, the trial demonstrated a 42% reduction in new sexually transmitted HIV infection in the intervention communities compared with the control communities. This study provides strong evidence of the impact of improved treatment of symptomatic STIs.

1.3 HIV-positive individuals who have other Reproductive Tract Infections are more likely to transmit HIV to others

Studies have shown that when HIV-positive individuals are also infected with other STIs and reproductive tract infections, their bodies are more likely to shed or release HIV cells in both ulcerative and inflammatory genital secretions. They are also more likely to shed more numbers of HIV infected cells compared to people with HIV infection alone.

A study conducted recently in Malawi measured the concentration of HIV-1 RNA (the genetic material of HIV virus) in cell free seminal plasma from HIV-1-seropositive men with urethritis before and after antibiotic therapy. The results were compared with those seen in HIV-1 seropositive men who had no clinical evidence of urethritis. Results showed that HIV-1 positive men with urethritis had HIV-1 concentrations in seminal plasma eight times higher than those in seropositive men without urethritis. After the urethritis patients were treated for their STI, the concentration of HIV-1 RNA in semen decreased significantly.
These results suggest that urethritis increases the infectiousness of men with HIV-1 infection and that programmes which include detection and treatment of STDs in patients already infected with HIV-1 may help to curb the HIV epidemic.

1.4 STIs and HIV – biological relationships

a)  Increased Susceptibility
  • 10 fold increased risk of HIV transmission in presence of Ulcerative STIs
      and 4 fold increased risk of HIV transmission in presence of Inflammatory
  • Ulcerative STIs results in breaks in genital tract lining or skin and create a portal of entry for HIV. Micro erosions caused by STIs also facilitate HIV entry.
  • Both Ulcerative & Non ulcerative STIs & RTIs increase the concentration of T-cells in the genital secretions and genital linings that can serve as target of HIV.
b) Increased infectiousness
  • HIV positive individuals who are also infected by STIs have shown increased concentration of HIV (viral load) in the genital  lesions.
  • Both ulcerative & Non Ulcerative STIs and RTI increase HIV shedding in the genital secretions of HIV positive individual. Bleeding from the genital ulcer is another contributory factor.
  • There is mounting evidence that some STI pathogens become more virulent in presence of HIV related immune deficiency.

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