Why are cities considered effective locations for biological attacks?

Cities are considered effective locations for biological attacks primarily due to the higher population density found in urban areas. A dense population means that pathogens can spread rapidly from person to person, increasing the potential impact of a biological agent. The close proximity of individuals in urban environments enhances transmission rates, making it easier for an attack to result in widespread illness and disruption.

While other factors such as access to public transportation, availability of medical facilities, and the presence of government buildings may play roles in the dynamics of an attack or its aftermath, they do not directly relate to the primary concern of rapid spread. Public transportation can facilitate movement but does not inherently increase the spread of biological agents. Medical facilities, though vital for response and treatment, do not contribute to the initial spread of a biological attack. Government buildings might be targeted for symbolic reasons but do not affect transmission dynamics as population density does.