May's top articles included news on HIV, Lyme disease, updates to nosocomial pneumonia guidelines, and more.
Much has happened in the world of infectious diseases this past month, but a few things stand out. During a conference hosted by the Centers for Disease Control and Prevention, researchers shared findings regarding Candida auris, a seemingly harmless fungal infection. In addition, IDSA/ATS guidelines for nosocomial pneumonia have been updated after 11 years. Researchers also take on the tough questions, such as how close we are to a cure for HIV, and if the medical community behind the times in treating Lyme disease.
Research presented at the 2017 Annual Epidemic Intelligence Services (EIS) Convention notes that Candida auris, a fungus that is usually harmless to healthy individuals, may cause high-risk health conditions in immunocompromised individuals.
C. auris has been linked to several hospital outbreaks and caused several deaths outside of the United States. In addition, this specific strain of Candida is frequently mistaken for another: Candida haemulonii. Sharon Tsay, MD, EIS officer in the Mycotic Diseases Branch of the Centers for Disease Control and Prevention (CDC), went on to note that the CDC recommends lab and health professionals ensure that their diagnostic systems are up-to-date and can differentiate between the fungal strains.
When commenting on the unique aspects of C. auris, Dr. Tsay said, “It really affects the sickest of the sick, [such as] people in nursing homes, infants, and individuals with other medical conditions. Also, it is resistant to at least two of three, if not all three, main types of antifungal drugs. Finally, it is easily transmitted in hospitals because, typically, Candida lives on the body as part of a healthy body, but this strain also can exist for long periods of time on surfaces in hospitals and cause outbreaks.”
In addition, Paige Armstrong, MD, who did studies on C. auris in 2016 in Colombia, said in a media briefing at the EIS conference that concern regarding the fungus was raised after two separate neonatal intensive care units experienced outbreaks.
According to researchers at the University of North Carolina (UNC), School of Medicine, HIV can infect macrophages. Although this may seem bad, the researchers have managed to find the silver lining. A press release from UNC states that “The discovery of this additional viral reservoir has significant implications for HIV cure research.”
In addition, the myeloid lineage cells “have been shown to express CD4, CCR5, and CXCR4 and to be susceptible to HIV and [simian immunodeficiency virus] SIV infection in vitro and in vivo.”
Their research group’s study set out to see how HIV-infected macrophages would respond to antiretroviral therapy (ART), and if the macrophages serve as a reservoir even after treatment. The researchers used a “humanized myeloid-only mouse model devoid of T cells.” The researchers found that ART was able to suppress HIV from replicating in macrophages, but that it virus “rebounded” when treatment was interrupted in one third of the study animals.
However, these were not the research team’s only findings.
It has been 11 years since the first guideline for nosocomial pneumonia was jointly published by The Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS).
IDSA and ATS have made 7 key updates to the guidelines. These include changes to classification of healthcare-associated pneumonia, which was originally placed under the spectrum of hospital-acquired pneumonia and ventilator-acquired pneumonia, due to a concern over risk of infections with multidrug-resistant pathogens in this population. After reviewing more recent data, however, it was seen that these patients are, in fact, not at increased risk for infection with multidrug-resistant infections. Therefore, healthcare-associated pneumonia has been reclassified under community-acquired pneumonia.
The updated guidelines also highlights risk factors for multidrug-resistant pathogens, as well as recommendations for empiric antipseudomonal agents for those at high risk for multidrug-resistant pathogens.
According to the CDC, in 2015, approximately 400,000 new individuals were diagnosed with Lyme disease in the United States, where the tick-borne disease has been recognized for more than 40 years. In addition, the United States also recognized 19 tick-borne diseases, some of which can be transmitted simultaneously from the bite of one infected tick.
The subject of chronic Lyme disease is a controversial one; however, according to a study published in PLOS ONE, between 36% and 63% of individuals who acquired Lyme disease go on to develop a chronic form of infection (post-treatment Lyme disease).
In addition, clinical practice guidelines for Lyme disease appear to be outdated and not included in the National Guidelines Clearinghouse (NGC). In addition, “These guidelines are most often used to deny treatment to patients with chronic disease, and so their current absence from the NGC is beneficial to patients who may need long-term antibiotic therapy and have been denied this through use of these guidelines.”
An HIV diagnosis a few years ago often meant a death sentence, with infection rapidly progressing to full-blown AIDS. However, medicine has come a long way since then.
With the introduction of protease inhibitors in the mid 90s, death rates related to HIV started dwindling. Unfortunately, since HIV remains to be a “stubborn virus,” leaving the human body with “an inefficient response” to the virus, a vaccine has yet to be developed. However, researchers still have hope that we are close to a cure for infection with this lethal virus.
Speaking with Contagion®, Roger Sharpiro, MD, MPH, associate professor at Harvard School of Public Health, and who specializes in reducing the incidence of mother-to-child infection transmission and morbidity and mortality rates in congenitally infected infants, said, “Treatment has been our biggest success story to date… Because of effective treatment, what was once a universally fatal disease can now be controlled with 1 pill, once a day.”
“Ongoing research is now exploring how to push treatment even further and control the virus with longer-acting treatment or… approaches such as monoclonal antibodies—but we are not there yet.”