Pus in the throat, appearing as white or yellow patches on the tonsils or pharynx, is a strong indicator of a bacterial infection. While SARS-CoV-2, the virus responsible for COVID-19, often causes a sore throat, it does not directly lead to pus formation. If pus develops in a person with COVID-19, it is usually an indirect consequence, stemming from a compromised immune system or a separate infection. This distinction is important for understanding symptoms and determining the appropriate course of medical treatment.
Typical COVID-19 Throat Symptoms
A sore throat is a frequently reported symptom of a COVID-19 infection. This discomfort is usually described as a scratchy, dry, or painful sensation in the pharynx. The symptoms tend to appear alongside other signs of a respiratory viral illness, such as a cough, fatigue, and headache.
As a viral infection, COVID-19 causes inflammation and irritation of the throat lining, but it rarely produces the white patches of pus on the tonsils. These visual signs are characteristic of bacterial involvement. If a person’s sore throat is caused only by the SARS-CoV-2 virus, the throat will likely appear red and swollen without any significant white or yellow exudate.
The Role of Secondary Bacterial Infections
The indirect connection between COVID-19 and pus in the throat occurs through a complication known as a secondary bacterial infection. A severe viral illness, such as COVID-19, can compromise the immune system and damage the protective mucosal lining of the respiratory tract. This creates an environment where opportunistic bacteria can flourish.
When bacteria invade the throat tissues weakened by the viral infection, the body mounts an immune response that results in the accumulation of dead white blood cells, tissue debris, and bacteria, which is the substance we recognize as pus. For instance, a COVID-19 infection can be followed by an infection like bacterial tonsillitis or a peritonsillar abscess, where pus collects in the tissues surrounding the tonsil.
Other Common Causes of Pus in the Throat
Pus in the throat is often caused by pathogens entirely unrelated to the COVID-19 virus. The most common bacterial cause is Group A Streptococcus (GAS), which leads to Strep Throat. Strep Throat is characterized by a rapid onset of severe throat pain, a high fever, and the presence of white patches or streaks of pus on the tonsils, often without the cough or congestion typical of a viral cold or COVID-19.
Certain viral infections can also lead to pus-like exudate, most notably the Epstein-Barr virus, which causes mononucleosis. Mono causes significant inflammation in the throat that can produce white patches on the tonsils, along with intense fatigue and swollen lymph nodes. Fungal infections, such as oral thrush, can also present as white patches in the mouth and throat.
When Medical Intervention is Necessary
The appearance of pus in the throat, regardless of a person’s COVID-19 status, is a strong signal to seek medical evaluation. Since pus indicates a bacterial infection, a medical professional must determine the cause to prescribe the correct treatment. Only a rapid strep test or a throat culture can accurately diagnose the presence of Group A Streptococcus, which requires antibiotic treatment to prevent serious complications.
If a person tests positive for COVID-19 and subsequently develops pus in the throat, dual testing for a bacterial infection is often necessary. A doctor will decide if antibiotics are warranted to target the bacterial component, while supportive care manages the viral symptoms. Individuals should seek immediate emergency care if they experience severe symptoms like difficulty breathing, an inability to swallow, or a muffled voice, as these may indicate a more serious condition like a peritonsillar abscess.