Which of the following diseases is primarily caused by bacterial infection?

Streptococcal pharyngitis, commonly known as strep throat, is primarily caused by bacterial infection, specifically by the bacterium Streptococcus pyogenes, also known as Group A Streptococcus. This illness is characterized by symptoms such as a sore throat, fever, and swollen lymph nodes. The infection can lead to further complications if not treated, which is why it is important to recognize it as a bacterial infection.

In contrast, influenza is caused by a viral infection, specifically by the influenza virus. This respiratory illness primarily affects the upper respiratory tract and is associated with symptoms such as fever, cough, and body aches.

HIV/AIDS is caused by a viral infection from the human immunodeficiency virus (HIV), which attacks the immune system, leading to acquired immunodeficiency syndrome (AIDS) over time.

Malaria is caused by parasitic infections, specifically by parasites belonging to the genus Plasmodium. Mosquitoes are typically the vectors responsible for transmitting these parasites to humans.

Recognizing the specific etiological agents of these diseases—bacteria for streptococcal pharyngitis, viruses for influenza and HIV, and parasites for malaria—is crucial for understanding their treatment and prevention strategies.