Moraxellaceae is a family of bacteria that are primarily found in the environment, including soil and water. They are Gram-negative, rod-shaped organisms that can be part of the normal flora in humans and animals. Some members of this family are known to be opportunistic pathogens, meaning they can cause infections, particularly in individuals with weakened immune systems. The family includes several genera, such as Moraxella, which is best known for causing respiratory infections. These bacteria can be transmitted through respiratory droplets and are often associated with conditions like sinusitis and bronchitis. Understanding Moraxellaceae is important for diagnosing and treating infections they may cause.