Tuberculosis (TB) is often misunderstood, especially its transmission. It is not a bloodborne pathogen; its spread differs significantly from blood-borne infections, impacting prevention. This misconception can confuse how to protect oneself and others.
What Defines a Bloodborne Pathogen
Bloodborne pathogens are infectious microorganisms found in human blood that can cause disease. These pathogens include viruses such as Hepatitis B (HBV), Hepatitis C (HCV), and Human Immunodeficiency Virus (HIV). Transmission occurs when infected blood or other potentially infectious body fluids enter another person’s bloodstream. This happens through needlestick injuries, sharps exposures, or contact with mucous membranes or non-intact skin. Bloodborne pathogens can also be transmitted through sexual contact or from mother to child during birth.
How Tuberculosis is Transmitted
Tuberculosis is an airborne disease caused by the bacterium Mycobacterium tuberculosis. Unlike bloodborne pathogens, TB spreads through the air when a person with active lung or throat TB coughs, sneezes, speaks, or sings. These actions release tiny airborne particles, known as droplet nuclei, into the environment. These infectious droplet nuclei contain the bacteria and can remain suspended in the air for several hours.
When another person inhales these airborne particles, the bacteria can settle in their lungs, potentially leading to infection. The likelihood of transmission depends on factors such as the concentration of infectious droplet nuclei in the air and the duration of exposure. Tuberculosis is not transmitted through casual contact, such as shaking hands, sharing food or drinks, or touching contaminated surfaces.
Strategies for Preventing TB Spread
Given its airborne transmission, preventing TB spread focuses on controlling airborne particles. Good ventilation in indoor spaces helps dilute and remove contaminated air, reducing infectious droplet nuclei. Natural light, particularly ultraviolet (UV) light, can also help kill TB bacteria in the air.
Respiratory hygiene is another measure, involving covering the mouth and nose with a tissue or elbow when coughing or sneezing. Prompt disposal of used tissues and hand hygiene further reduce potential spread.
In healthcare settings, N95 respirators are used by healthcare workers to filter airborne particles and protect against inhalation. Patients with suspected or confirmed TB may wear surgical masks to contain their respiratory droplets.
Early diagnosis and timely treatment of individuals with active TB are also important, as effective medication can quickly render a person non-infectious. Isolation of infectious individuals, such as in specialized rooms with negative air pressure, helps prevent the bacteria from spreading to others.