Preventing the Spread of Infectious Diseases at Work
Preventing the spread of communicable diseases means blocking transmission, or "blocking the chain of infection." This can be done by removing one or more of the conditions that are necessary for a disease to spread. Transmission of disease can be stopped by:
As with other hazards, the best way to protect workers is to get rid of the hazard. The strategy for protecting workers from infectious diseases should start with the most effective methods.
Maintaining a building at the proper temperature and humidity can reduce the risk of many diseases. Agents need moisture to live. Keeping the humidity below 60 percent helps to prevent the growth of fungus and molds in the building.
Maintenance of the ventilation system helps to prevent the spread of germs. For example, the bacteria that cause Legionnaire’s disease live in cooling towers. Cooling towers should be drained when not in use and biocides should be used to kill the bacteria that cause the disease. Bringing in enough fresh air and exhausting air outside lowers the level of air contaminants.
Isolation rooms: Local ventilation blocks transmission of airborne diseases. For example, a patient or inmate with an active case of tuberculosis should be in a private room with a special ventilation system. This isolation room is kept under negative pressure. As explained in Chapter 4, this means the air pressure inside the isolation room is less than the air pressure outside the room. The flow of air keeps TB bacteria from escaping outside the room.
Laboratory hoods and biological safty cabinets: Lab hoods and similar equipment prevent contact with infectious agents by drawing them away from workers. The infectious agents are collected on a filter or are discharged to the outside. See Figure 1.
Safer needles and sharp devices
A needleless injection system prevents needlesticks. In addition, there are needles and other sharp instruments available that are designed to reduce the risk of needlesticks or other skin punctures when giving injections or starting an intravenous line. For example, one type of needle is attached to a spring so that it retracts after the fluid is injected. Another type of syringe is designed to cover the needle with a plastic sheath after the injection is given.
Autoclaving prevents the spread of disease by killing infectious agents. Contaminated waste is sterilized before disposal.
The way certain jobs are organized can be changed to reduce workers’ exposure to infectious agents. For example, limiting the number of workers who care for or come into contact with an infectious patient or inmate reduces the number of workers who are exposed.
Careful housekeeping is a basic part of infection control. Careful housekeeping includes:
Giving workers vaccinations can block the spread of certain diseases. Depending on the type of workplace, the employer should provide or pay for vaccinations against diseases to which their workers may be exposed. Examples include:
There are also flu shots and vaccinations for measles, chicken pox and other diseases. Some employees, such as health care workers, may be required to be vaccinated or document their immunity. Workers should talk to their doctor about their jobs and ask which shots they should receive. The doctor may also want to do blood tests to see if previous vaccinations are still effective. If not, workers may need to be re-vaccinated for certain diseases, or given a booster shot.
Frequent handwashing prevents the spread of disease by killing germs. Hands should be washed after using the rest room, between clients and when gloves are removed after contacting infectious material or patients.
Personal protective equipment (PPE)
As with any hazard, gloves, masks and other protective clothing are the last line of defense. If no other protective measures are taken, workers will have no protection if the equipment breaks, does not fit or fails for any reason. In some situations there is no other way to protect against infection, such as wearing gloves when handling blood or body fluids.
Approved respirators must be selected on the basis of the hazards to which the workers are potentially exposed. For example, a N95 or more protective particulate respirator must be used for protection against tuberculosis according to infection control guidelines issues by the Centers for Disease Control and Prevention. Surgical masks are NOTrespirators.
Gloves keep infectious agents away from workers' skin. Gloves must be made of latex, rubber or other material that keeps fluids off the skin.
Latex gloves and other products containing latex can cause allergic skin reactions. The symptoms for latex allergy include: swelling, itching, burning, redness and hives. Severe reactions can involve breathing problems, sneezing, itchy eyes, and in some cases toxic shock! Workers who are sensitive to latex should avoid gloves and other products containing latex. Exposure to latex can be reduced by substituting other materials for latex, using low-protein, powder-free gloves; using cotton glove liners; and using a mild soap to wash hands. Some facilities no longer use latex gloves and have gloves made of other materials.
Face shields and eye protection
The eyes and mucous membranes in the nose and mouth can be openings for infectious agents to enter the body. Face shields or eye protection should be worn when there is a chance the worker could be splashed by contaminated fluids. The face should also be covered during procedures that produce a fine mist or aerosol containing tiny droplets of infectious material.
Gowns and protective clothing
Gowns and coverings prevent contact with infectious agents.