Hologic Inc, Marlborough, Mass, has received FDA clearance for its Group B Streptococcus (GBS) assay on the Panther Fusion system.

GBS is a bacterium naturally carried by some women. If passed from a mother to her baby during labor, however, it can lead to serious health consequences and even death for the newborn from illnesses such as blood poisoning, meningitis, or pneumonia.1

Hologic GBS assay

Hologic Panther Fusion group B Streptococcus assay.

In clinical studies, the Panther Fusion GBS assay exhibited 100% sensitivity compared to culture-based testing methods.2 The assay will also increase testing options for healthcare providers, as it is validated for the two enrichment broths that make up 95% of the samples used on the market. The assay also has less-stringent requirements for clinical sample storage and transport than culture-based tests.3

“A nucleic acid amplification test is the most sensitive and reliable screening method available today for identifying pregnant women who are carriers of this serious bacterium,” says Tom West, president of the diagnostic solutions division at Hologic. “As a leader in diagnostics for women, our commitment to providing high-quality, life-saving solutions now extends to newborns, who can be fatally impacted by GBS infection.”

If a pregnant woman carries the GBS bacterium—Streptococcus agalactiae—it can spread to the amniotic fluid after the onset of labor, ultimately transmitting to the baby during childbirth.3 While common and not harmful to healthy adults, the bacterium can cause serious health consequences or even death if passed to an infant.3 An estimated 18% of women in the United States are carriers, making universal screening imperative so that perinatal transmission to the baby can be prevented.4

Tom West, Hologic.

Tom West, Hologic.

Since the first screening guidelines were put in place in the 1990s, the rate of early-onset GBS has decreased almost 86%. Today, the Centers for Disease Control and Prevention recommends that all pregnant women be tested for GBS at 35–37 weeks’ gestation.1 This recommendation is endorsed by the American Academy of Family Physicians, the American Academy of Pediatrics, the American College of Nurse-Midwives, the American College of Obstetricians and Gynecologists, and the American Society for Microbiology.4

The Hologic Panther Fusion module can be added to existing Panther systems to extend testing capabilities. The system adds the capacity to run polymerase chain reaction assays to the transcription-mediated amplification assays that are performed on the base Panther system. As a result, labs will retain all the key benefits of the Panther platform—including full sample-to-result automation, the ability to run multiple tests from a single sample, random and continuous access, sample processing with rapid turnaround time, and stat capabilities—while simultaneously streamlining and refining specimen processing to maximize efficiency.

The Panther Fusion GBS assay joins the Panther Fusion Flu A/B/RSV, Panther Fusion Paraflu, and Panther Fusion AdV/hMPV/RV assays, all of which received FDA clearance in 2017. The GBS assay has also been CE marked for diagnostic use and is commercially available in Europe.

For more information, visit Hologic.


  1. Group B strep (GBS): clinical overview [online]. Atlanta: Centers for Disease Control and Prevention, 2018. Available at: www.cdc.gov/groupbstrep/clinicians/clinical-overview.html. Accessed September 16, 2018.
  1. Panther Fusion GBS assay [US package insert AW-17997, rev. 001]. San Diego: Hologic, 2018.
  1. Verani JR, McGee L, Schrag SJ. Prevention of perinatal group B streptococcal disease: revised guidelines from CDC, 2010 [online]. Morbidity and Mortality Weekly Report. 2010;59(RR10):1–32. Available at: www.cdc.gov/mmwr/preview/mmwrhtml/rr5910a1.htm. Accessed September 16, 2018.
  1. Seale AC, Bianchi-Jassir F, Russell NJ, et al. Estimates of the burden of group B streptococcal disease worldwide for pregnant women, stillbirths, and children. Clin Infect Dis. 2017;65(suppl_2):S200–S219; doi: 10.1093/cid/cix664.