Health officials still searching for cause of bacteria at Prince George's Hospital Center's NICU

Two days after Prince George's Hospital Center closed down its Neonatal Intensive Care Unit (NICU) for the second time in three months, officials say one of the two babies who tested positive for Pseudomonas is now battling an infection related to the potentially deadly bacteria.

In total, five infants were transferred out of the hospital's NICU on Wednesday and have been taken to Children's National Medical Center in Washington D.C. to be treated.

Back in August, Pseudomonas was found in pipes and sinks, which caused the hospital's NICU to shut down until Oct. 4. Nine babies were moved from the hospital at that time.

However, hospital officials said the water system is not believed to be the cause for the recurrence of the bacteria this time and called it "puzzling."

"Upon reflection and close examination of the facts as we've looked back over the last few months, I do believe that the earliest identified Pseudomonas cases earlier this year could have prompted additional escalation and investigation," said Sherry Perkins, the Chief Operating Officer for Dimensions Healthcare System.

A team of experts from the Centers for Disease Control and Prevention as well as health officials from Prince George's County and the state of Maryland and the University of Maryland Medical System are helping Prince George's Hospital Center to try to figure what is causing the bacteria to show up again.

"We take very seriously our obligation to get to the bottom of this matter, learn how and why it happened and do everything possible to prevent it from happening again," said Neil Moore, the president and Chief Executive Officer for Dimensions Healthcare System.

Experts have been looking at infant deaths at Prince George's Hospital Center and there have been seven babies who have died in the NICU since the beginning of the year. The bacteria was immediately ruled out for the deaths of three of those babies.

Dr. Colleen Hughes-Driscoll, an assistant professor of pediatrics at the University of Maryland School of Medicine, said, "Among those [other] four deaths, two could not be connected to Pseudomonas. After extensive chart review conducted to date, while there is a likelihood, it remains unclear whether Pseudomonas can be conclusively linked to the two other infant deaths. Is it possible? Yes. Can we say for sure? Unfortunately, no. We may never know conclusively."

Pseudomonas is a bacterium that can cause infections in humans and can lead to illness in small babies with health challenges as well as other vulnerable patients. It can be often found widely in the environment such as water soil and can colonize on pipes, faucets and surfaces.