The arrest of a nurse accused of injuring patients recovering from heart procedures at a Tyler hospital shocked the community and left many wondering how someone charged with helping patients could end up charged with murder in one of their deaths.
William George Davis, 34, who has remained jailed on $2 million bond since his April 10 arrest, recently was indicted on one count of murder and two counts of aggravated assault with a deadly weapon.
His indictment on June 21 came a year and a day after the first patient he is accused of harming suffered significant injury from a profound and unexplainable incident resembling stroke-like symptoms.
Shocking as it is, it is not the first time a health care worker has been accused of injuring patients in Texas or in East Texas.
Dr. Kenneth Kizer, of The University of California School of Medicine, and several colleagues conducted extensive research on the topic and found that Texas is home to more known instances of health care serial murder than any other state in the U.S.
Their research dates back to the 1970s and includes information on at least 35 health care workers who have been formally charged with killing patients.
Five of those cases happened in Texas, beginning in 1981 with a Kerrville woman who became known as "The Angel of Death."
The former nurse confessed to killing children in her care at a San Antonio hospital.
Genene Jones, 67, is serving concurrent 99-year and 60-year sentences in state prison for the 1982 killing of 15-month-old Chelsea McClellan and the sickening of 4-week-old Rolando Santos, who survived.
Jones has served decades in prison following her murder conviction in 1984. She was scheduled to be released in March, but prosecutors filed additional murder charges, citing new evidence.
A Texas prosecutor said authorities believe Jones could be responsible for the deaths of up to 60 children.
In a separate case, an Austin woman was convicted of killing two elderly men by overdosing them with potassium in an Austin rehabilitation center in 1988.
Susan Hey was sentenced to two 50-year sentences for the crimes.
In 2005, a Mission woman who worked as a home nurse was convicted of murder.
Jeanine Hannah was sentenced to 99 years in prison for injecting Margaret Bradley, 65, of McAllen, with a deadly dose of insulin in 2002, according to court documents from Hildago County.
Another nurse, Vickie Dawn Jackson, was sentenced to life in prison for killing at least 10 patients in 2000 at the Nocona General Hospital.
Jackson injected the patients with a drug used to stop breathing and allow insertion of a breathing tube, according to a CNN article.
A fifth case occurred when a Lufkin nurse was charged with killing five patients at a dialysis clinic there in 2008.
A 2012 article in the Longview News-Journal said Kimberly Saenz, 38, was charged with capital murder in the deaths and aggravated assault in the case of five other patients injured at the DaVita Dialysis clinic in Lufkin. Saenz was sentenced in 2012 to life in prison.
Officials became aware of Saenz through a Lufkin fire official who pleaded for an investigation at the clinic because of an abnormal amount of calls for paramedics at the facility.
The research by Kizer and his colleagues, which appeared in the American Academy of Forensic Sciences and the Joint Commission Journal on Quality and Patient Safety, went beyond those Texas cases and looked at health care serial murders across the globe.
Their work shows that health care serial murders share some common characteristics of settings, circumstances and psychopath type traits.
In one of his papers, Kizer and a co-writer said a majority of health care serial murders are of patients in a heath care setting and the suspects are employed by the facility where the incidents occur.
Other commonalities in the research show the incidents generally occur more than 30 days apart and the employees commit the acts while they are performing their assigned duties.
Kizer's research also indicates most of the incidents were suspected by coworkers long before any formal investigations began.
In the Davis case, an arrest affidavit said a coworker confronted Davis after a patient, Joseph Kalina, 58, became unresponsive after recovering from heart surgery.
Further investigation revealed Kalina suffered a cerebral air embolism that was believed to have caused him to be paralyzed and in need of lifelong care.
Kalina is one of seven people police identified as victims of Davis. His family hired a San Antonio-based law firm to represent them after the news about Davis broke.
A Longview-based law firm is representing the widow of Christopher Greenaway, the man whose murder Davis is charged with, and the family of a man identified by the Tyler Police Department as John Doe 4 in an arrest affidavit.
The firm is representing the families in connection with Greenaway's death and John Doe 4's severe and permanent injuries that police believe happened at the hands of Davis while he was recovering from heart surgery at the Christus Mother Frances Louis and Peaches Owen Heart Hospital.
Davis worked for Christus Mother Frances Hospital-Tyler for five years and was terminated Feb. 15, about a week after hospital officials went to police with their concerns. Prior to that, he worked for Christus Good Shepherd Medical Center in Longview from 2011 to 2013. All the incidents included in the arrest warrant affidavit occurred at Christus Mother Frances Louis and Peaches Owen Heart Hospital in Tyler.
The hospital set up a hotline for anyone with questions to call, and to date the hotline has received about 200 calls, hospital officials said.