The COVID-19 Swab test is an important part of the anti-epidemic work, and it is extremely important to standardize the operation of sampling techniques.
All sampling operations must be standardized. In order to provide a strong guarantee for the accurate reporting of subsequent nucleic acid testing.
Nasopharyngeal (NP) swabs are the primary sample type for respiratory molecular pathogen testing.
During the 2019 novel coronavirus infectious disease (COVID) pandemic, NP swabs became central to the detection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2).
Unfortunately, NP swab collection can be very uncomfortable for some patients.
Because when collecting nasal swabs, a relatively long flocked swab, is directly inserted into the nasal cavity of the person being collected.
However, nasal swabs will not cause pain if the operator is appropriate, but some people with sensitive noses or diseases may experience mild discomfort.
Np swab covid test meaning?
Np swab is the nasopharyngeal swab test, which refers to a relatively conventional method for detecting viruses.
Nasal swab testing mainly involves inserting a relatively long sterile flocked swab into the patient’s nasal cavity.
It was then collecting secretions from the nasopharynx through the nasal cavity.
And then testing these secretions in various aspects, such as bacterial culture And drug sensitivity test to determine the source of infection and the type of microorganisms.
Symptomatic treatment according to the test results, and a drug sensitivity test can also be used to determine which drug is more sensitive.
Use the more sensitive drug for treatment.
What should medical staff pay attention to when collecting nasopharyngeal swabs?
All healthcare professionals performing nasopharyngeal swab tests must wear the recommended personal protective equipment (PPE), which should include N95 masks, disposable caps, goggles, protective clothing, latex gloves, and shoe covers.
Nasopharyngeal flocked swabs: performed with the patient sitting upright with the head in an upright position.
What is A Covid-19 NP Swab?
The subject needs to tilt his head back.
Nasopharyngeal swabs are not along the nostrils, but perpendicular to the face, entering from the nasal passages.
When collecting, do not enter violently when encountering resistance or the subject feels obvious pain.
When taking nasopharyngeal sampling, the operator can stand behind the subject and does not need to look directly at the nasal cavity.
In addition, there is basically no gag reflex, the tolerance is good, and the risk of exposure is relatively low.
After sampling, the individual tested may have a sneeze reflex, immediately use an elbow or a tissue.
A small number of subjects may have a little nosebleed after sampling, which can usually be stopped on their own.
When taking a nasopharyngeal swab, it can stay in the nasopharynx for a longer time in order to obtain a more adequate sample.
Studies have shown that the positive rate of nasal swab samples is higher than that of throat swab samples, that is, the efficiency of nasal swabs for virus swab detection is higher than that of throat swabs.
What can a nasopharyngeal swab detect?
Used for nasopharyngeal sampling for respiratory viruses such as influenza, swine flu, bird flu, and hand, foot and mouth.
A nasopharyngeal culture
The reasons for false negatives
1. Patient: The virus content may be too low. The nucleic acid swab detection reagent has certain requirements for the virus presence in the infected person. If the virus is too low, existing methods may not detect it.
The onset of new coronary pneumonia patients will go through a process from asymptomatic after infection, to mild symptoms, to severe symptoms.
2. Collection of specimens: false negatives cannot be completely avoided.
Many experts have concluded from practical work that the positive rate of sputum and bronchoalveolar lavage fluid samples collected from the lower respiratory tract is higher than that of oro-nasopharyngeal swabs from the upper respiratory tract; the positive rate of nasopharyngeal swab samples is higher than the Oropharyngeal swab.
Improper collection site, for example, when collecting oropharyngeal swabs, the depth of the collection is not enough;
Nasopharyngeal swabs are not enough deep into the nasal cavity, etc., and most of the collected cells may not contain viruses, which may cause false negatives.
3. Detection reagents: At present, the quality of the reagents on the market may vary.
4. In addition to the test reagents themselves, laboratory specifications will also have an important impact on the test results. Specimen transportation and storage conditions, standardized operations in clinical laboratories, result interpretation and quality control are all key factors to ensure the accuracy and reliability of test results.
Prevent false negatives
Incorrectly performed nasopharyngeal swabs may lead to a greater likelihood of patients receiving false-negative test results.
False-negative results are an important issue to address, as these results can cause patients who are positive for some diseases to unknowingly transmit highly contagious diseases, especially COVID-19, too many others.
Therefore, adequate training of testers on how to perform nasopharyngeal swab tests reliably is critical. Use high-quality detection reagents. learn more.