The differences between nasal swabs and throat swabs

I. Sampling sites

1. Nasal swabs
   • Nasal swabs are sampled by inserting the swab into the nasal cavity. Usually, the swab needs to be slowly inserted along the bottom of the nasal cavity. For adults, the insertion depth is generally about 2 – 3 cm, and for children, the insertion depth should be appropriately reduced according to age, and then the sample is collected by rotating and wiping inside the nasal cavity.
2. Throat swabs
   • Throat swabs sample the throat area. Generally, the person being sampled is asked to open their mouth wide and say “ah” to fully expose the throat, and then the swab is extended to the throat area, focusing on wiping the tonsils and the back of the pharynx to obtain the sample.

II. Sampling difficulty

1. Nasal swabs
   • Sampling with nasal swabs is relatively more difficult. Because the space inside the nasal cavity is relatively narrow, the insertion depth and force need to be carefully controlled during the operation to avoid damaging the nasal mucosa. Moreover, the sampling process may cause discomfort such as soreness, stinging, or tearing in the nasal cavity of the person being sampled, and some people being sampled may unconsciously avoid due to discomfort, increasing the sampling difficulty.
2. Throat swabs
   • The sampling difficulty of throat swabs is relatively small. However, when the swab touches the base of the tongue or the deep part of the throat during the operation, it is easy to cause a strong nausea reflex in the person being sampled. Especially for people with a more sensitive throat, vomiting may occur, thus affecting the smooth progress of sampling.

III. Detection accuracy

1. Nasal swabs
   • In some diseases, nasal swabs may have higher detection accuracy. For example, for some pathogens that mainly reproduce in the nasal cavity, nasal swabs can collect the pathogens more directly. For infections caused by rhinoviruses, the samples collected by nasal swabs can better reflect the infection status.
2. Throat swabs
   • For diseases that mainly infect the throat area, the detection accuracy of throat swabs is relatively high. However, the distribution of pathogens in the respiratory tract may change. Sometimes, due to situations such as less secretions in the throat area of the person being sampled during sampling, the number of pathogens collected by throat swabs may be insufficient, affecting the accuracy of the test results.

IV. Comfort of the person being sampled

1. Nasal swabs
   • When sampling with nasal swabs, the person being sampled will mainly feel discomfort in the nasal cavity, such as a foreign – body sensation, soreness, and slight stinging, and sometimes tearing may occur, but nausea is usually not caused.
2. Throat swabs
   • Sampling with throat swabs is easy to cause a nausea reflex and even vomiting in the person being sampled, which will bring relatively strong discomfort to the person being sampled, especially when the person has eaten recently before sampling, and this discomfort will be more obvious.

V. Application scenarios

1. Nasal swabs
   • They are more commonly used in the diagnosis of some nasal infectious diseases. For example, in the bacterial detection of sinusitis, nasal secretions are collected by nasal swabs for bacterial culture and drug – sensitivity tests to determine the types of infected bacteria and select appropriate treatment drugs. At the same time, in the detection of some respiratory infectious diseases, such as the detection of viral infections with the nasal cavity as the main infection site, nasal swabs are also important sampling tools.
2. Throat swabs
   • They are widely used in the detection of common respiratory infectious diseases, such as the detection of influenza and COVID – 19 virus infections. Because these virus infections often cause inflammatory reactions in the throat area, throat swabs can well collect relevant pathogens. In addition, in the diagnosis of some throat – infecting diseases, such as the pathogen detection of tonsillitis, throat swabs are also commonly used sampling methods.