In this feature, a panel of IDSA members identifies and critiques important new studies in the current literature that have a significant impact on the practice of infectious diseases medicine.
- Late Pregnancy and Postpartum: The Highest Risk Period for HIV Acquisition
- Removing Gloves as a Requirement for Contact Precautions
- Hepatitis A Vaccine Effective in HIV+ Individuals During an Outbreak, But with Slower Seroconversion
Click here for the previous edition of Journal Club. For a review of other recent research in the infectious diseases literature, see “In the Literature,” by Stanley Deresinski, MD, FIDSA, in each issue of Clinical Infectious Diseases.
Late Pregnancy and Postpartum: The Highest Risk Period for HIV Acquisition
Reviewed by Manie Beheshti, MD
The World Health Organization cites HIV as the leading cause of death worldwide among women of childbearing age (15-44 years). Pregnancy is known to cause changes in the immune system that may heighten the risk of HIV acquisition, however the clinical data has been unclear in this regard.
In perhaps the best data available to date, a recent study published in the July 1 issue of The Journal of Infectious Diseases helps clarify the HIV acquisition risk in pregnancy and the postpartum period. Utilizing large databases from two previously published studies (the Partners in Prevention study and the Partners PrEP Study), investigators in seven African countries studied 2,751 HIV serodiscordant couples; 686 pregnancies were identified, and 82 incident HIV infections occurred during the study period. Data included HIV-infected male partners’ HIV viral load and circumcision status, frequency of sex acts (including condomless sex), and presence of sexually transmitted infections.
After adjusting for various factors, including male partner viral load, use of HIV pre-exposure prophylaxis (PrEP), and age, HIV acquisition probability in females was calculated during four distinct time frames: nonpregnancy, early pregnancy (up to 13 weeks gestation), late pregnancy (from 14 weeks gestation to the end of pregnancy), and postpartum (until 6 months after pregnancy). Compared to the nonpregnant, nonpostpartum periods (relative risk [RR] 1.0), the highest HIV acquisition risk was in late pregnancy (adjusted RR 2.82) and postpartum periods (adjusted RR 3.97). As expected, a linear relationship was noted between probability of HIV acquisition and the male partner’s HIV viral load.
This study importantly identifies periods of up to four-fold higher risk of HIV acquisition in women of childbearing age. Implications could include more widespread use of PrEP, more vigilant screening practices, and reinforcement of safe sex practices during the most vulnerable periods. Targeting this at-risk group could have an impact on transmission to female partners in serodiscordant couples and, in turn, maternal-to-child transmission of HIV.
Removing Gloves as a Requirement for Contact Precautions
Reviewed by Zeina Kanafani, MD, MS, FIDSA
A recent study in the American Journal of Infection Control examined whether hand hygiene without the use of gloves would be enough to eliminate hand contamination among health care workers (HCWs) caring for patients colonized or infected with methicillin-resistant Staphylococcus aureus (MRSA) and/or vancomycin resistant Enterococcus (VRE) who are placed on contact precautions.
Over a period of two weeks, HCWs performed routine patient care while exposure to bodily fluids was not expected. The HCWs were observed until there was contact of their ungloved hands with the patient as well as their surroundings. After the HCWs performed hand hygiene, microbiological samples were obtained by pressing all five fingertips onto agar plates. Three hand hygiene methods were used until hands were dry: two pumps of alcohol-based hand rub (ABHR), three pumps of ABHR, or soap and water wash.
A total of 240 specimens were collected (120 MRSA and 120 VRE samples): 40 MRSA and 40 VRE plates after two pumps of ABHR, 40 MRSA and 40 VRE plates after three pumps of ABHR, and 40 MRSA and 40 VRE plates after soap and water wash. Culture was positive for 1 colony-forming unit of MRSA from two plates from two HCWs who performed hand hygiene using two pumps of ABHR. Both HCWs had negative cultures after repeating the procedure another time. All other cultures were negative.
The authors concluded that routine hand hygiene is effective in removing MRSA and VRE from ungloved hands. The technique of performing hand hygiene should be stressed as an important determining factor in the effectiveness of this approach (adequate volume of ABHR and soap and adequate contact time). While further studies are needed to validate the results of this study, it appears possible to eliminate the mandatory use of gloves during care of patients colonized or infected with MRSA and VRE as long as proper hand hygiene techniques are followed.
Hepatitis A Vaccine Effective in HIV+ Individuals During an Outbreak, But with Slower Seroconversion
Reviewed by Erica Kaufman West, MD
Hepatitis A virus (HAV) outbreaks are usually related to contaminated food exposure, but recent outbreaks have been reported among men who have sex with men (MSM) and injection drug users who engage in oral-anal sex and use contaminated drugs, respectively. Although CDC does not recommend routine HAV vaccination for HIV-infected patients unless there are other risk factors, such as intravenous drug use, the Advisory Committee on Immunization Practices has recommended HAV vaccination for MSM since 1996.
In a recently published Hepatology article, researchers described a real-world evaluation of the HAV vaccine, investigating serologic responses and vaccine effectiveness in HIV-infected individuals during an outbreak in Taiwan. They looked at HIV+/HAV- patients who were advised to receive two doses of HAV vaccine, six months apart. They followed those who agreed to be vaccinated (1,001) and those who declined (532). At the end of the study, 965 of 1,001 had completed the full two-dose series. Compared to the unvaccinated group, the vaccinated group was slightly older, included more MSM, had a slightly higher CD4 count (554 versus 540 cells/mL), and included fewer participants with CD4 count < 200 cells/mL (4.6 percent versus 9.4 percent). During follow-up, 65 developed HAV positivity, five in the vaccinated group and 60 in the unvaccinated group, translating to an incident rate in the vaccinated group of 3.7 per 1,000 person-years of follow-up compared to 99.3 per 1,000 person-years of follow-up in the unvaccinated group. The authors noted that all five participants in the vaccinated group who developed HAV did so before the second dose was due (an average of three months after the first dose).
Historically, HIV-negative individuals have a high seroconversion rate of > 90 percent four weeks after the first dose. The authors here found only 8 percent of HIV-positive patients seroconverted at that time. In fact, when they checked just before the second dose, the rate of seroconversion was still quite low, around 60 percent. The authors recommend considering a modified vaccination schedule for HIV-positive individuals in an HAV outbreak, including a booster dose at week four.
|For a review of other recent research in the infectious diseases literature, see “In the Literature,” by Stanley Deresinski, MD, FIDSA, in each issue of Clinical Infectious Diseases: