Upper respiratory infections caused by viruses are among the most common types of infections experienced by individuals. The viruses responsible for these infections include the rhinovirus, influenza virus, and respiratory syncytial virus (RSV), among others. These viruses are primarily transmitted through respiratory droplets, which are released when an infected individual coughs or sneezes. Additionally, they can be spread through direct contact with contaminated surfaces. Symptoms of viral upper respiratory infections typically include a runny or stuffy nose, sore throat, cough, and mild fever. In some cases, these infections can also lead to more severe respiratory complications, such as bronchitis or pneumonia. It is important to note that viral upper respiratory infections are self-limiting and do not require antibiotic treatment. Instead, symptom management and supportive care, such as rest and hydration, are key in alleviating discomfort and promoting recovery. While viral infections are more common, bacterial infections can also contribute to the development of upper respiratory infections. Streptococcus pneumonia, Haemophilus influenzas, and Moraxella catarrhalis are among the common bacteria responsible for these infections. Bacterial upper respiratory infections are often secondary to a viral infection, as the weakened immune system allows bacteria to thrive. Like viral infections, bacterial upper respiratory infections are transmitted through respiratory droplets and direct contact with contaminated surfaces. The symptoms of bacterial infections are often more severe and persistent compared to viral infections. These symptoms may include high fever, severe sore throat, persistent cough, and thick yellow or green nasal discharge. In some cases, bacterial upper respiratory infections can lead to complications such as sinusitis or middle ear infections. Antibiotics are usually prescribed to treat bacterial upper respiratory infections and prevent further complications. Apart from viral and bacterial causes, other factors can also contribute to the development of upper respiratory infections. Fungal infections, such as those caused by Aspergillus or Candida species, can affect individuals with weakened immune systems or those exposed to contaminated environments. These infections can lead to symptoms such as nasal congestion, persistent cough, and sinus pain. Allergies play a significant role in upper respiratory infections as well. Allergic rhinitis, commonly known as hay fever, can cause inflammation of the nasal passages and increase susceptibility to viral and bacterial infections. Environmental factors, such as exposure to pollutants or irritants, can also contribute to the development of upper respiratory infections.