Study finds race, male sex associated with MRSA bacteremia
A multicenter study of patients with MRSA bloodstream infections caused by a community-associated strain of the pathogen has identified race as a primary association, researchers reported yesterday in the Journal of Infectious Diseases.
For the study, researchers retrospectively evaluated hospital-onset methicillin-resistant Staphylococcus aureus (HO-MRSA) and hospital-onset methicillin-susceptible S aureus (HO-MSSA) bloodstream infections diagnosed at a large public hospital and a large academic medical center in Chicago. The objective was to determine whether sex and racial disparities exist for S aureus bacteremia and to use whole-genome sequencing (WGS) to characterize transmission pathways associated with USA300, a common community-associated MRSA strain.
The researchers identified 156 HO-MRSA and 256 HO-MSSA bloodstream infections at the two hospitals from 2009 through 2013, and multivariate analysis showed that male sex, African-American race, and non-Hispanic white race/ethnicity were significantly associated with HO-MRSA bacteremia, while Hispanic ethnicity was negatively associated. Analysis of WGS data from a sample of the USA300 MRSA bacteremia isolates further revealed that African-American race was the only factor associated with phylogenic clustering of patient isolates, and that there is an intermixing of USA300 transmission networks between the community and the hospital.
The authors say the findings suggest that MRSA bloodstream infections caused by USA300 are likely due to colonizing strains acquired in the community before infection. "Future infection prevention interventions for USA300 MRSA may need to extend to the community for maximal benefit," they write.
May 9 J Infect Dis study
WHO says probe looking at other sources in Liberian illness cluster
The World Health Organization (WHO) said today that Liberia's health ministry has informed it that samples from four people who died as part of an unexplained illness cluster tested positive for Neisseria meningitidis serotype C. It added that although the recent test results suggest meningitis as the likely cause of illness and death in those patients, an investigation is still under way to determine if the bacterium is responsible for other illnesses in the cluster.
As of May 9, the number of cases remained at 31, including 13 deaths.
In a May 5 statement, the WHO had said that findings hinted at point-source contamination, and samples from individuals and the environment, including food, are being analyzed and tested. The search for other sick patients also included collecting food and drink samples for toxicology testing. Preliminary sampling of water sources that serve affected areas ruled out bacterial contamination. Heavy metal and chemical testing is ongoing.
The WHO said while Liberia waits for the full results of toxicology tests, country health officials are exploring if meningitis vaccination is appropriate. Also, the WHO said it supports ongoing epidemiologic and laboratory investigations to identify the etiologic agent of the illness cluster to guide the next control steps.
May 10 WHO statement
May 5 WHO statement
VLP Zika vaccine successful in preclinical study
A novel virus-like particle (VLP) Zika vaccine elicited high titers of virus-neutralizing antibodies in mice, according to the vaccine's manufacturer, TechnoVax. The results of the study were published earlier this week in PLoS Neglected Tropical Diseases.
"The ZIKA VLP vaccine offers an effective and safe strategy to create a prophylactic vaccine that protects against Zika infection, as well as its serious effects such as microcephaly," said Jose M. Galarza, MD, TechnoVax chief executive officer said in a press release from the company.
Though VLPs are identical to a virus, they lack the genetic ability to replicate. And because vaccines made with VLPs do not require attenuating a virus, they are touted for their safety profiles and immunogenicity.
In other Zika news, a woman in the Washington, DC, area has Zika after being mistakenly told she was negative for the mosquito-borne virus last year. At the time of the testing mistake, the woman was pregnant.
Four hundred tests from a DC-area lab were sent to the Centers for Disease Control and Prevention (CDC) for retesting earlier this year after it was discovered that technicians made an error when handling test samples. According to the Associated Press, it is not known if the woman's pregnancy was affected by Zika.
May 8 PLoS Negl Trop Dis study
May 9 TechnoVax press release
May 9 Associated Press story
Senate confirms Scott Gottlieb as FDA commissioner
The full Senate yesterday voted by a 57 to 42 margin to confirm Scott Gottlieb, MD, as President Donald Trump's commissioner of the Food and Drug Administration (FDA), the New York Times reported.
Gottlieb, age 44, had held various positions at the FDA during George W. Bush's administration, including as deputy commissioner. Democratic legislators have objected to his nomination over his close ties to the pharmaceutical industry, but many Republicans have said his business experience will benefit Gottlieb in his new role at the FDA.
In a statement yesterday, Health and Human Services (HHS) Secretary Tom Price, MD, congratulated Gottlieb on his confirmation as FDA commissioner. "We are excited to partner with Dr. Gottlieb to protect and promote the health of the American people. Dr. Gottlieb brings considerable experience to the FDA. His background will be crucial for keeping the FDA as the gold standard for safe treatments while advancing new, innovative solutions to the many public health challenges our nation faces."
May 9 Times story
May 9 HHS statement
Tests confirm tularemia in Southern Hemisphere animals
Researchers from Australia yesterday reported the first confirmation of Francisella in Southern Hemisphere animals. Ringtail possums that had been suspected as the source of isolated human infections in Australia tested positive for the bacterium, which causes tularemia.
The group reported its findings yesterday in Emerging Infectious Diseases.
As part of efforts to explore undiagnosed diseases in Australian wildlife, the investigators probed possible infectious causes of ringtail possum deaths that involved acute necrotizing enteritis or hepatitis. They included eight possums that were found dead in Sydney from 2000 to 2009.
In analyzing RNA from liver samples, the researchers didn't find any viral or fungal pathogens, but F tularensis was abundant. Sequencing tests suggested F tularensis holarctica.
Individual liver samples were then screened for F tularensis, and two were positive. They were obtained from ringtail possums found in Sydney's north shore area during mass mortality events, one in May 2002 and the other in August 2003. An isolate was obtained from one of the two samples. The isolate and sequences from the original liver RNA data clustered with an Asian holarctica subspecies that includes the japonica biovar.
Testing of eight other ringtail possums and three rabbits with similar symptoms were negative for F tularensis, suggesting that there are other sources for acute necrotizing enteritis and hepatitis in the animals.
The team concluded that native ringtail possums in Australia might be a natural reservoir or host of tularemia and could serve as sentinels for disease activity that could pose a threat to humans.
May 9 Emerg Infect Dis report