Penicillins have been found effective for which type of infection?

Penicillins are a class of antibiotics that are primarily effective against bacterial infections. They work by interfering with the synthesis of bacterial cell walls, ultimately leading to the death of the bacteria. Skin infections are often caused by bacteria such as Staphylococcus aureus and Streptococcus pyogenes, which can be effectively treated with penicillins.

While the other types of infections mentioned, such as viral and fungal infections, do not respond to antibiotics, neurological infections can refer to a variety of causes, including viral and fungal infections as well. Thus, the effectiveness of penicillins is specifically aligned with treating bacterial skin infections, confirming the choice of skin infections as the correct context for the use of penicillins.