HCWs in genetic trials should be trained, followed

In lieu of national consensus guidelines for infection control and gene therapy, individual clinicians have reviewed the literature and devised preventive measures. The following recommendations were developed by Martin Evans, MD, hospital epidemiologist at the University of Kentucky Chandler Medical Center in Lexington, and colleagues.1

Each gene therapy vector must be evaluated individually, considering such factors as the likelihood the viral vector may replicate, patient shedding, mode of transmission, and people at risk for secondary infection, they noted. Precautions should be determined for each study by committees that include representation from such departments as biosafety, infection control, and pharmacy. Additional recommendations are summarized as follows:

Health care workers

• Health care workers with known immunocompromising conditions should be discouraged from working on gene-therapy protocols.

• Workers should undergo formal training by infection control staff in conjunction with employee health staff and the principal investigator of the study. Educational materials should include information about the vectors, procedures, known and unknown risks, and potential transmission of agents to the general public. Use of standard precautions and personal protective equipment should be reviewed. The importance of hand washing should be emphasized. Isolation precautions for the patient should be described.

• The employee health service should be made aware of the study and of the individual health care workers involved. There should be arrangements, as needed, for 24-hour postexposure evaluation and management. Pertinent immunization should be made available if possible.

• Surveillance should be performed on clinical, pharmacy, and laboratory personnel to determine if cross-transmission of vectors occurs. Protocols should be developed for the collection and testing of baseline sera or other appropriate specimens. Testing should be performed periodically during the study to determine if cross-transmission occurs.

Outpatients and admitted patients

• Patients should be treated only in areas approved by the institutional biosafety committee or alternative authority. These areas and their waiting rooms should be physically separated from areas frequented by immunocompromised patients who are not part of gene-therapy protocols.

• If possible, rooms should be private, with a sink and commode in the room.

• An appropriate transmissions precautions sign (airborne, contact, etc.) should be posted on the door.

• Patients should be restricted to their rooms during treatment. All tests and procedures requiring patient transport from the room that are not necessary for the study should be postponed if possible. When volunteers leave the room for tests or procedures, they should wear isolation garb if recommended by the institutional biosafety committee.

• Dedicated equipment (stethoscopes, sphygmomanometers, thermometers, etc.) should be available. These items should be disinfected appropriately before being reused.

• Linens should be placed in fluid-resistant bags and handled with standard precautions.

• All meals should be served with disposable dinnerware and trays in the room.

• Visitors should be strictly limited to immediate family (adults only). Visitors should follow the isolation precautions recommended by the institutional biosafety committee.

• Care must be taken to prevent spills of the vector or aerosolization (such as expressing liquid from a syringe).

• Kits specific for the agent should be readily available to manage spills.

• All waste should be placed in red biohazard containers, handled as regulated medical waste, and incinerated. Personnel handling waste should wear disposable latex gloves. The room should be decontaminated according to the institutional biosafety committee recommendations when the patient leaves.

• Infection control staff should be notified if a gene therapy patient is referred to the hospital for studies, admission, or readmission. Patients admitted to the emergency department should be placed in an isolation room on contact precautions unless advised otherwise by infection control staff.


1. Evans ME, Lesnaw JA. Infection control in gene therapy. Infect Control Hosp Epidemiol 1999; 20:568-576.