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Flu Test Swab

Posted on 2022年3月18日2022年3月30日 by Dr. Lee

The COVID-19 pandemic has actually added another layer of complexity to the flu season ahead of schedule. COVID and the flu share many similar signs and symptoms, which certainly makes diagnostic screening even more important this flu season.

What is a flu swab test?

Flu is the abbreviation of Influenza. This disease is not unfamiliar to us. It is an acute respiratory infection caused by influenza virus.

Influenza is very contagious and spreads very quickly. Once you have flu symptoms, you must go to the hospital for relevant examinations in time to determine the type of flu before symptomatic treatment.

Every year when the seasons change, the virus will also increase due to changes in temperature. This period is also the time when we are most prone to getting sick.

Among them, influenza is a very common epidemic infectious disease. Influenza is familiar to most people, but not very well known to a few people.

Getting a quick, accurate diagnosis is of course critical to driving treatment decisions.

Influenza testing can be done with blood tests, nasopharyngeal swabs, etc.

How to Test for Flu with a Swab.

Which Swab Test is More Accurate?

Discovering the right flu test is critical to ensuring accurate results. Using high-quality items—including appropriate swabs, shipping media, and testing devices—can help to properly identify influenza and reduce the potential spread of infection. Influenza testing needs to detect the influenza virus.

After infection with influenza, the influenza virus usually invades the nasopharynx first, which can be detected by a nasopharyngeal swab.

Influenza virus can also enter the blood and can be detected by a blood test. Influenza is a relatively serious respiratory infectious disease.

After the infection, the systemic symptoms are more obvious, such as high fever, general weakness, and sore limbs.

The recovery of the disease is also relatively slow, and it takes about half a month.

Each of the influenza tests listed above can be performed using a nasopharyngeal (NP) swab, throat swab, NP swab, nasal or endotracheal aspirate, or saliva test.

Covid Test Throat Swab

To perform an NP flu swab test, follow these steps:

Choose a flocked swab with excellent absorption and elution, such as CellMedical’s Nasopharyngeal Swab CM-96000N 6″ Sterile Flocked Swab with Breakpoint 90mm.

With the patient’s head tilted back, slowly insert the flocked swab into the nasal cavity.

Place the swab directly into the nostril directly back (not up) and at the level of the nasopharynx to the distance determined on the swab handle.

Rotate the swab approximately 3 to 5 times and hold in place for 5 to 10 seconds to obtain a sample.

Remove the sampling swab and insert into a virus sampling tube containing 1 to 3 ml of virus transport medium.

Break the flocked swab along the breakpoint.

Label the vial with the appropriate customer information.

How long does a flu swab test take?

Throat swab test belongs to a class of medical test methods. A medical sampling swab is used to take a small number of secretions from the pharynx of the human body, inoculate it in a special petri dish, and then put it into a temperature control device for cultivation. Throat swab test can understand the patient’s condition, oral mucosa and throat infection. As for how long the results will take, depending on the number of people tested, some hours, some a day, some a week.

How accurate is the flu swab test?

The flu nasopharyngeal swab test is more accurate when the virus load is sufficient.

This is used to determine whether the human body has the flu.

But if the test comes back positive, that would require sampling and testing of those who came into contact with the patient.

It can prevent the spread of influenza, and it is necessary for suspected patients to be properly isolated, placed separately, and tested.

Nasopharyngeal swabs are commonly used clinically to detect viruses.

That is, take a sampling flocked swab and gently wipe the patient’s nasopharynx, and then take samples for testing.

Np Swab Covid Test Meaning

Posted on 2022年3月16日2022年4月7日 by Dr. Lee

Np Swab Covid Test Significance Np Swab is the English abbreviation of nasopharyngeal swab.

This article provides information on how to properly perform nasopharyngeal swab sampling, how to analyze samples taken from swabs.

Nasal swab? What is the difference between a nasopharyngeal swab and a nasal swab?

Nasopharyngeal Swab Pcr Test

Nasopharyngeal Swab vs Nasal Swab (Anterior Nasal Swab)

What is the method of nasopharyngeal swab?

Collection of specimens from the surface of the respiratory mucosa with nasopharyngeal flocked swabs is a procedure used for the diagnosis of Covid-19.

A nostril sample collection is usually one of the nursing care.

What is the nasal swab technique?

Part of the inspection method is done using sub-diagnostics and collecting diagnostic samples from the membrane. Rotate for 10-5 seconds while touching both walls, then use a cotton swab with 1 mid-hole in one nostril.

In the same way in the other nostrils: usually preferred for people – and used in my own testing. The same goes for technology.

Which swab test is more accurate?

Nasopharyngeal swabs are generally the recommended sample collection technique for COVID-19 testing.

Additionally, a 2012 comparative study showed no significant analytical differences between the two influenza detection technologies.

In addition to being the typical testing approach for the diagnosis of COVID-19.

The nasopharyngeal swab: is likewise regularly utilized for the detection of different viruses and bacterial infections.

How do we perform nasopharyngeal swab sample collection?

Flocked Tip Swab

Healthcare experts need to execute these tests in a specialized and also sanitized room that prevents the spread of the infection.

All healthcare specialists administering the nasopharyngeal swab examination have to wear the suggested personal protective devices (PPE), of which ought to include an N95 mask, non reusable cap, goggles, dress, latex gloves, and also footwear covers.

When the individual sitting upright as well as their head in a straight position, as this provides very easy exposure and also access to the nasal floor, which is vertical to the facility axis of the person’s face.

The staff places the swab into the client’s nose in the same direction as the nasal cavity and diaphragm floor.

As long as there are no obstructions existing within the nasal dental caries, the swab will certainly remain to relocate this instructions until it reaches the nasopharynx.

Once the swab reaches the nasopharynx, finishes two full 360-degree rotations to enable the secretions from this area.

When we take the swab out of the individual’s nose. Immediately insert into a vial with medium.

Nasopharyngeal Swab Procedure.

What can a nasopharyngeal swab find?

As previously pointed out, a nasopharyngeal swab: is extensively utilized to identify (SARS-CoV-2) infection, which is the infection that causes COVID-19 disease.

Identified via nasopharyngeal swabs, several of which include rhinovirus, and adenovirus. flu. respiratory syncytial virus (RSV). (HPIV). (HMPV) as well as (EV).

Given that the nasopharynx is generally home to a high number of both nonpathogenic as well as pathogenic microorganisms. This testing approach can additionally be utilized to detect particular bacterial pathogens.

Such as Streptococcus pneumoniae, Haemophilus flu, as well as Moraxella catarrhalis.

A diagnostics firm, for example, has just recently presented a novel nasal swab that gathers nasal epithelial cells for the early molecular discovery of lung cancer in both current as well as previous smokers.

We obtained nasopharyngeal swab samples, and the current standard for diagnosing SARS-CoV-2 is real-time fluorescent polymerase chain reaction (RT-PCR).

Pcr test nasal swab and an antigen test difference for covid 19

Commonly, the RT-PCR test will measure several various RNA gene targets, such as several of the envelope (env), nucleocapsid (N), spike (S), RNA-dependent RNA polymerase (RdRp) as well as ORF1 genes.

RT-PCR test is an analytical technique suitable for SARS-CoV-2 discovery because of its reliability and affordability.

As well as sensitivity, especially when compared to different analysis techniques like cell culture, antigen discovery, and serological approaches.

There are numerous reasons that negative test outcomes can develop as a result of an incorrect nasopharyngeal swab method.

One instance includes the numerous locations in between the opening of the nose and also the nasopharynx where the screening workers can experience resistance.

Commonly, a knowledgeable caregiver can acknowledge when the sampling swab has actually gotten to 9-10 centimetres into the nasal dental caries.

If the swab does not reach this depth, it has not accurately tasted liquid from the nasopharynx and can for that reason not adequately determine the existence of a disease within this location of the body.

For this reason, it is critical to assess whether employees receive proper education on how to accurately perform nasopharyngeal swab testing.

Vtm Kits How To Use

Posted on 2022年3月4日2022年3月22日 by Dr. Lee

Cellmedical Virus Sampling Transport Kit

Product Description:

Specifically designed for the collection, transport and preservation of virus-containing samples, such as influenza, avian influenza, and respiratory viruses such as hand, foot and mouth.

Disposable medical flocked swab, consisting of a plastic rod and a nylon fibre tip that can be broken at any point.
VTM and VTM-N (inactivated virus transport medium) are available for selection.
Ready-to-use tear-off packaging, convenient and quick, to avoid possible cross-contamination during use.
Equipped with a biosafety sample bag, which is convenient for placing samples and paper documents, the transfer is safe and reliable.

10ml Viral Transport Medium VTM Swab Tube Kits

10ml VTM Swab Tube Kits

With 3 ml VTM Kits in a 10 ml tube with sterile flocked swabs.

Recommended for collection and transport of viruses such as COVID-19, Swine Flu etc, CellMedical is a vtm kit manufacturer.

Our virus transmission medium or VTM kit is specially used to collect, process and transport suspected virus samples.

These VTM swab kits have antimicrobial representatives to make sure that the virus is not killed while suppressing various other microbial development.

With cryoprotectants, laboratories can keep these samples extracted through these ICMR accepted screening kits for an extensive period.

These viral transport medium sets are tested to maintain the infection's RNA throughout transportation.

Vtm Kit Uses

Sampling using a virus transport medium sampling includes throat swab sampling and nasal swab sampling.

Nasopharyngeal swab sampling:

The collector holds the patient's jaw with the left hand, measures the distance from the tip of the nose to the earlobe with a sampling swab. Marks it with a finger. Insert the sampling swab into the nasal cavity in the direction perpendicular to the nose (face). The swab reaches the minimum distance.

It should reach half the length from the earlobe to the tip of the nose, let the swab stay in the nose for 15-30 seconds, gently rotate 3-5 times, and withdraw the swab. Wipe the other hole with another swab.

Immerse the swab head in the sampling solution, squeeze the swab head several times in the sampling solution. Break the tail of the swab forcefully, and discard the tail of the swab.

Throat swabs

Hold the swab in the right hand to wipe the bilateral pharyngeal tonsils and posterior pharyngeal wall. Immerse the swab head in the sampling solution. Squeeze the swab head several times in the sampling solution. Break the tail of the swab forcefully, and discard the tail of the swab.

Break the swab at the breakpoint of the sampling flocking swab rod, discard the tail, and close the tube cap

Label the vtm sampling tube with information as required.

Specimens should be transported to the corresponding influenza surveillance network laboratory within 2 working days after collection.

The storage temperature should be 2-8°C;

Specimens should avoid repeated freezing and thawing.

Our VTM tubes adhere to federal government standards.

Developed to maintain safety, ease, and also dependability, these sets are among the best readily available viral testing tools, making us one of China's finest VTM kit manufacturers.

In addition, we are additionally professional producers of VTM Kits, RNA removal, rapid antigen kits, and so on.

Which can assist lab testing and also supply much better testing results.

CM Viral Transport Medium Sets (VTM Kits) are made from Hanks' Well Balanced Salt Option and also consist of safety protein prescription antibiotics to regulate microbial contamination as well as barriers to manage the pH.

1. Are you a Distributor or a Manufacturer?

We are a manufacturer, warmly welcome your visit. Please try to contact our sales representative first by email or phone. We will make the appointment and the most reasonable planning for your transportation.

2. Where is your factory located?

Guangdong, China.

3. Do you do Business to Business?

Yes, Most of our transactions are Business to Business

4. Do you offer OEM?

Yes, we support custom production, OEM and so on, and develop products with customers.

Covid Mouth Swab Test

Posted on 2022年1月12日2022年3月22日 by Dr. Lee

Covid Mouth Swab Test

Three key points for oral swab collection!

The oral swab is an all-in-one system that can collect, stabilize, transport and purify DNA from saliva in advance, providing a painless and risk-free new way to collect microbial DNA for disease control and prevention.

Accidentally, it is easy to cause people to be infected with the new coronavirus, and the surface detection is not sensitive, and the operation is easy to lead to standardized operation.

Awareness Check Tool:

Testing equipment for testing equipment, including testing tools for testing equipment, testing equipment for testing equipment, testing equipment for testing equipment, including safety testing equipment.

Virus Sampling Tube & Nasopharyngeal Swab (Inactivated)

Oropharyngeal sampling points:

1. Sufficient light: Good lighting should be provided for both indoor and outdoor light sources. If necessary, flashlight lighting should also be provided.

2. Full exposure: The three anatomical locations for oropharyngeal swab collection must be completely exposed, and a spatula should be used when exposing bilateral tonsils.

3. Accurate location: The oropharyngeal swab should not touch other parts, such as the tongue, chin, etc., except for the three designated locations, so as not to be stained with saliva and affect the quality of specimen collection.

Covid Mouth Swab Test Pre-harvest preparation

Routine screening:

Work clothes, medical protective face shield, work cap, gloves, isolation gown, goggles (anti-fog) or face shield.

Influenza or suspected cases:

Wear work clothes, medical protective masks, work caps, gloves, isolation gowns or protective clothing, goggles (anti-fog) or protective face shields, and add shoe covers or boot covers if necessary.

Order of protective clothing:

Work caps that do not need to be worn. → Protective masks (Wearable head-mounted type and a tightness test should be performed after wearing them.)→ No shoes protective clothing (Boot covers should be added instead of foot protective clothing.) → Surgical gloves. → Protective screen or goggles.

Employee Registration Protection:

Tooling or isolation gown. → Medical-surgical mask or medical protective face shield. → Disposable work cap.

Protective clothing should be replaced every 4 hours and should be replaced in time if there is moisture or pollution.

Supplies preparation: Throat swab sampling sleeve, tongue depressor, inspection sheet and barcode, transport bag or refrigerator, 75% alcohol, pen.

Nucleic acid collection

1. We asked the examinee to tilt his head slightly, open his mouth.

And lift the upper jaw vertically to expose the posterior pharyngeal wall.

2. Use the front end of a sterile long cotton swab to quickly rub up and down 3-5 times on the bilateral pharyngeal tonsils.

And 3-5 times on the upper and lower sides of the posterior pharyngeal wall.

3. After scraping, open the sampling tube. Insert the front end of the sample vertically into the sampling tube. Insert the sampling tube. Break the sampling tube to expose the outer part of the tube. And tighten the cap.

Place the sampling tube in a biosafety sealed bag, mark the name and other information on the sampling tube, and complete the sampling.

Notice:

1. When sampling with the Covid Mouth Swab Test, it is best not to call “ah”, because once the sampled person is a positive patient, he will shout “ah”, exhale the virus in large quantities, and form aerosols in the sampling area.

When sampling, we advise patients to open their mouths and not yell or take deep breaths.

2. During the sampling process, one person collects and one person disinfects.

When the sampler holds the cotton swab, try to take it as far as possible.

3. A large number of samplers collect oropharyngeal swabs face-to-face with the sampled person.

Therefore, during the sampling process, the breath exhaled by the patient can easily and directly pose a great threat to the medical staff.

To reduce the risk of the sampler, we recommend that healthcare workers sample at a 45-60 degree angle to reduce risk.

End of Swab Test sampling

1. Spray and disinfect the generated medical waste layer by layer, and tie the gooseneck double medicine bag tightly to ensure that the seal is tight, has no damage, and has no leakage. Do not squeeze the contents of the medical waste bag. Annotation generates point information.

2. The order of unprotected items: hand hygiene → take off the protective face shield or goggles → hand hygiene → take off the protective clothing (take off the boot cover together) → hand hygiene, take off gloves, hand hygiene → take off the protective mask and Disposable work cap → hand hygiene.

Utm Swab | Swab Kits

Posted on 2021年12月8日2022年3月30日 by Dr. Lee

Utm swab | swab kit COVID-19 test

On this page:

What are UTM Swab, Swab Kits?

Who does not need to undergo a nasal swab test?

Quick questions and answers about COVID-19 testing?

What are UTM Swab, Swab Kits?

On November 9, 2021, South Africa detected a B.1.1.529 variant of the new coronavirus from a case sample for the first time. In just 2 weeks, the mutant strain became the absolute dominant mutant strain of the new crown infection cases in Gauteng Province, South Africa, and its growth was rapid.

The form of New Coronavirus is still very serious.

As the first step of covid-19 detection, the importance of sample collection and preservation is beyond doubt.

The influencing factor is sample collection; If there is a problem with the collected samples, the results will be invalid regardless of the subsequent processing.

Selecting appropriate virus transport media and collecting flocked swab can improve the detection efficiency of new crowns.

Utm Swab, Swab Kits

With flocked Swab; 3ml inactivated medium;10ml tube

Get Latest Price

Email:flockedswabs@gmail.com

Item No.	VTM-B-CM040311S vtm kits
Description:	Nasal nylon flocked Swab.
Material:	nylon flocked fibers+medical grade plastic handle,3ml inactivated medium;10ml tube.
size:	Can be customized.
MOQ:	50000pcs.
Logo	printing on swab or paperbag.
Packing:	Sterilization packaging,Individual in Paper peeled pouch ,1000pcs per bag ,1000pcs per carton
Carton Size	655410520cm/655460570.
N.W./G.W.	9kg,9.2kg,9.6kg,5kg/22.5kg,20kg,18.5kg,16kg,14.5kg,10.8kg.
production time	10 days after the order confirmed.
sample lead time	20 days.
Shipping	FedEx,UPS,TNT,DHL.
usage	medical using, hospital use, home nursing, etc.

Who does not need to undergo a nasal swab test?

Should I do a UTM swab test for COVID-19?

Nasal Swab Test

1. Close contacts;
2. People returning from abroad;
3. Outpatients with fever;
4. New inpatients and nursing staff;
5. Employees of medical institutions;
6. Port quarantine and border inspectors;
7. Prison staff;
8. Staff of social welfare institutions.

Where do I take the COVID-19 swab test?

If your doctor or other health care provider recommends you to be tested for the new crown pneumonia virus, you can go to any nearby medical institution to check for a virus test. The medical institution can be a doctor’s office, an emergency centre, or a local pharmacy.

If I have symptoms related to new coronary pneumonia, will the cost of swab testing for new coronary pneumonia be covered by the insurance?

If you have symptoms of new coronary pneumonia or have been in close contact with a patient who has been diagnosed with new coronary pneumonia, please contact your doctor first to determine whether you should be tested for the virus. Use this to determine symptoms (such as fever, cough, fatigue, difficulty breathing, muscle pain, and vomiting).
After obtaining permission or approval, the cost of testing provided by medical service providers who can provide or order COVID-19 testing will total $0.

Question: What is Coronavirus (COVID-19)?

COVID-19 is a new variant of the very common viral family known as coronavirus, which can lead to respiratory tract infections, from the common cold to more serious diseases, such as severe acute respiratory syndrome (SARS). Although coronavirus is most commonly found in animal-like cattle, cats, and bats, in some cases, coronavirus can be transmitted and transmitted among humans, such as COVID-19 and SARS, of which nearly 8000 people were sick when they broke out in 2003.

Possible reasons for the emergence of Omi Keron mutants

According to the information currently shared by the new crown virus database GISAID, the number of mutation sites of the new crown virus Omi Keron mutant strain is significantly more than that of all the new crown virus mutant strains that have been circulating in the past two years, especially in the virus spike (Spike) protein mutations. . It is speculated that there may be three reasons for its emergence:

(1) After being infected with the new coronavirus, patients with immunodeficiency have undergone a long period of evolution in the body to accumulate a large number of mutations, which are transmitted by chance;

(2) a certain animal group infection New coronavirus, the virus undergoes adaptive evolution during the spread of animal populations, with a higher mutation rate than humans, and then spills into humans;

(3) This mutant strain has continued to circulate for a long time in countries or regions where the mutation monitoring of the new coronavirus genome is lagging. , Due to insufficient monitoring capabilities, the intermediate generation viruses of its evolution could not be detected in time.

Does the Omi Keron variant affect the UTM Swab Test reagents currently used in our country?

The genome analysis of the Omi Keron mutant strain showed that its mutation site does not affect the sensitivity and specificity of mainstream nucleic acid detection reagents in my country.

The mutation sites of the Omi Keron mutant strain are mainly concentrated in the highly variable region of the S protein gene.

The nucleic acid detection reagent primers and probe-target regions were published in the eighth edition of the "New Coronavirus Pneumonia Prevention and Control Program" (China CDC Virus The ORF1ab gene and N gene released by the disease to the world).

However, data from multiple laboratories in South Africa suggests that nucleic acid detection reagents that detect the S gene may not be able to effectively detect the S gene of the Omi Keron variant.

Should I use a mask in public?

Yes,’ if you’re going to a public place, it’s recommended to wear a mask. As long as the nose and mouth are covered, a scarf, handkerchief, or homemade non-medical mask can play a protective role.

It’s really important to wash your hands before and after putting on a mask.

Cell medical (Dongguan) Co., Ltd., a professional UTM Swab Kits and swabs manufacturer has many years of experience in medical application molding and flocking treatment heads and swabs. Their stable and reliable performance and excellent absorption and elution ability. Certificate:FDA,CE,EU,Free Sale,Export license based on (GMP).

We produce flocked swabs, VTM kits, Utm Swab, Swab Kits, Virus transport mediums, with multiple automatic production lines. We support custom production, OEM, and so on, and develop products with customers.

Cell medical (Dongguan) Co., Ltd.
E-mail：flockedswabs@gmail.com
No. 98, Wusha street, Chang’an Town, Dongguan City, Guangdong Province, China
Web：www.swabmanufacturer.com/

Saliva Sample Collection Kit :Disposable saliva DNA RNA sampling tube

Posted on 2021年9月18日2022年3月22日 by Dr. Lee

What is saliva collection kit?

In recent years, with the development of medicine, the examination technology has become more and more high-end. And the examination items have become more and more accurate.

Saliva is a complex mixture, which not only contains various proteins. It also contains DNA, RNA, fatty acids and various microorganisms. Therefore, it is possible to diagnose diseases by detecting saliva. Gene detection and analysis.

Saliva collector plays an important role in the process of collecting, transporting and storing saliva samples.

It is noninvasive and easy to self-management, and reduces the risk of medical staff exposure.

Saliva Collection Kit suitable for SARS-CoV-2 sample collection.

Nucleic acid detection is the most widely used new crown detection method.

Including PCR nasopharynx swab, oropharyngeal swab and saliva sample test.

High precision. As long as the collection, breeding and separation of nucleic acids are successful, there is basically no false positive or false negative.

But the sampling staff are easy to be exposed and the risk is high; With one more step of extracting nucleic acid, unskilled technicians are likely to fail to extract, resulting in false negative, or pollute with other people's samples, resulting in false positive.

COVID-19 Testing:PCR swab test,antibody test, and antigen test difference

Posted on 2021年9月17日2022年3月22日 by Dr. Lee

COVID-19 Testing :PCR swab test,antibody test, and antigen test difference.

PCR swab test（Nucleic acid test） and antibody / antigen detection are important means to confirm COVID-19, and also one of the important processes for patients to diagnose. But do you know what their detection principle is? What are the sample types? What is the inspection process and what are the problems?

COVID-19 nucleic acid test

Nucleic acid detection has the characteristics of early diagnosis, high sensitivity and specificity. At present, real-time fluorescence quantitative RT-PCR is the most widely used technology. PCR swab testing is a very effective way to identify SARS-COV-2.

1. Principle of COVID-19 test kits?

The researchers used sampling swabs to collect samples of the virus, targeting the unique gene sequence of the virus.

By PCR amplification of the virus sample, the target DNA sequence we selected increased exponentially.

Researchers can combine the amplified DNA sequence with pre added fluorescent labeled probe fragments to generate fluorescent signals.

The more target genes amplified, the stronger the cumulative fluorescence signal.

In Virus-free samples, no target gene was amplified. Therefore, researchers can not detect enhanced fluorescence signals.

That is, we do not carry COVID-19.

Therefore, nucleic acid detection is actually to detect the accumulation of fluorescence signal to determine whether there is viral nucleic acid in the sample.

COVID-19 test kits_PCR swab test（Nucleic acid test）

2. What are the methods of covid-19 testing samples?

Generally, PCR nasal swab test, pharyngeal swab, nasopharyngeal swab, sputum, bronchial lavage fluid, alveolar lavage fluid, etc.

Sampling swab consists of a nylon flocked swab.what is a flocked swab?

3. Steps of PCR swab test for COVID-19.

At present, pharyngeal swabs are the main sampling method for the diagnosis of novel coronavirus infection. Correct sampling is the key to improve the accuracy of nucleic acid samples collected from pharyngeal swabs. What are the factors affecting the accuracy of nucleic acid samples collected from pharyngeal swabs? There are three main aspects:

Depth of throat swab collection?

How long is the throat swab in contact with the mucosa?

Pharyngeal swab sampling “dot to dot” or wipe?

(1) Oral and pharyngeal swab collection tips

1. Sampling position: sit or semi-sit in decuffine position, with head slightly raised and mouth open, and head resting on the wall or against the back of the chair.

2. Standard sampling operation: Sampling personnel press the tongue of the subject with tongue depressors.

Pharyngeal swabs should be performed on both sides of the pharyngeal tonsil with “Quick wipe up and down” and on the posterior pharyngeal wall with “Quick left and right wipe” . Repeat 3 to 4 times.

Avoid contact with tongue, teeth and gums.

If you feel uncomfortable, quit, take a break, and try again.

Oropharyngeal Sampling flocked swab diagram

3. Precautions: Drinking water before oral and pharyngeal swab test will dilute the virus attached to the pharynx, especially drinking hot water will inhibit the activity of the virus.

In order to improve the accuracy of pharyngeal swab nucleic acid detection, we recommend that subjects do not drink water 15-30 minutes before the detection, so as to ensure the high accuracy of pharyngeal swab nucleic acid test.

(2) Nasopharyngeal swab collection tips

1.The sampling personnel shall collect samples from the side of the subject, and the subject shall pull down the mask to expose only his nostrils. If there is sneezing reflex, the subject can cover it with elbow or paper towel.

nasopharyngeal sampling diagram

2. Standard sampling operation: “one insertion, two stops and three rotations” — measure the distance from the tip of the nose to the front of the ear, half of the insertion length, usually about 4 cm for adults; Stay for 15-30 seconds to absorb nasopharyngeal secretions (depending on tolerance, minimum stay for at least 3 seconds; Rotate the nasopharyngeal swab for 1 week and slowly remove it.

The above is for the reference of sampling medical staff and patients, let’s work together to defeat COVID-19!

(3)Store samples

Dip the flocked swab head into the cell preservation solution(Virus transport medium), and tighten the tube cap immediately after breaking the tail;

Storage, put the sample tube into a sealed bag for timely inspection, and the inspection process requires a strict transportation environment, 2-8 ℃ storage.

(4) PCR TEST

Researchers operate nucleic acid extraction, extract inactivated virus samples for subsequent nucleic acid detection, and can use automatic equipment such as nucleic acid extractor.

Fluorescence PCR nucleic acid detection, that is, on the machine detection, the extraction of fluorescence PCR amplification reaction, needs 70-80 minutes.

process pcr test

4. What are the problems in nucleic acid testing?

False negative, due to improper sampling, improper specimen preservation, the use of different types of specimens and the use of different manufacturers of reagents may lead to nucleic acid test results “false negative” and missed diagnosis;

■ High requirements for detection equipment or platform, high sensitivity RT-PCR instrument is expensive, laboratory cleanliness and operator requirements are also high;

■ Nucleic acid testing is time-consuming. It usually takes 4-6 hours to complete an RT-PCR test.

Therefore, when the nucleic acid test is negative.

Relevant personnel can increase the detection of IgM and IgG antibodies to make up for the shortcoming that nucleic acid detection is easy to cause missed diagnosis.

COVID-19 Testing serum antibody test

Seven days after novel coronavirus pneumonia, the serum specific antibodies gradually emerged. The first is immunoglobulin IgM antibody, and then IgG antibody.

Thus, an elevated IgM antibody indicates a recent acute infection, and an elevated IgG antibody indicates a previous infection.

The biggest advantage of serological testing lies in its convenience and short detection time, which can effectively break through the limitations of existing detection technology on personnel and sites and shorten the detection time.

Novel coronavirus infection can be diagnosed in suspected cases if the serum specific IgM and IgG antibodies are positive, the IgG antibody changes from negative to positive, or the recovery period increases by 4 times or more than the acute period.

antibody test sampling process_COVID-19 Testing

1. Principle of serum antibody test kit?

The sample is added to the sample adding hole, and the sample will move forward along the detection card under the action of chromatography.

If the sample contains new coronavirus IgM antibody, the antibody will combine with colloidal gold labeled virus antigen to form a sandwich complex, which will show a positive result.

If the sample contains New Coronavirus IgG antibody, the antibody will bind to colloidal gold labeled New Coronavirus antigen and form a sandwich complex, which will show positive results.

The detection card also contains a quality control line (line C) to judge whether the chromatography process is smooth.

2. What are the sample types for serum antibody detection?

Generally, it is blood, including serum, plasma and whole blood.

3.COVID-19 antibody test in three steps

1. Open the aluminum foil bag of the test card, take out the test card and place it horizontally on the table;

2. Use a pipette to absorb serum/plasma/whole blood sample and add it to the sampling site. Then use the same method to absorb buffer drops and add them to the sampling hole of the test card.

3. Wait 15 minutes and read the result.

4. What are the problems in serum antibody detection?

■ False positive, individual patients with rheumatoid factors in the blood, heterosinophilic antibodies, autoantibodies, drugs and tumor cells, etc., easy to cause cross-reaction test, so occasionally false positive results;

■ False negative, due to the existence of a certain window period of serum antibody detection methods and the sensitivity of the detection kit will appear false negative results.

Therefore, serum antibody test is only used as a supplementary test for suspected cases of novel Coronavirus nucleic acid negative test and cannot be used as a diagnostic indicator for screening alone.

The combined use of serum antibody detection and nucleic acid detection can help to improve the detection rate of the disease and find out the confirmed patients as much as possible, which is more conducive to the control of the epidemic.

Interpretation of results of nucleic acid combined with IgG and IgM antibody detection

COVID-19 Testing antigen detection

A novel coronavirus antigen test can novel coronavirus be detected directly in human body samples. The diagnosis is fast and accurate, with low requirements for equipment and personnel.

antigen test kit_SARS-CoV-2

1. Principle of antigen detection kit?

SARS-CoV-2 , N, E and S protein antigens stimulate virus cells to produce specific antibodies.

2. What are the types of antigen test samples?

Usually samples from infected sites, e.g. oropharyngeal swabs, nasopharyngeal swabs, sputum, serum, plasma, etc.

3.COVID-19 antigen test in four steps

1. Drop the sample treatment liquid into the sample treatment tube;

2. Stir the sample swab and squeeze the tube wall until the specimen is fully eluted into the treatment solution;

3. Take out the detection card and add sample to the round hole;

4. Wait 15 minutes and read the result.

4. What are the problems in antigen detection?

■ False negative, higher sensitivity of antigen detection is required. Because New Coronavirus mainly affects alveolar and other lower respiratory tract. Therefore, sampling from the upper respiratory tract of nasopharynx and oropharynx cannot determine whether the pathogen can be detected. Or the sample contains a small number of viruses. All these factors may cause missed detection.

■ The preparation process is tedious and time-consuming. The development of the antigen kit requires the preparation of the recombinant antigen first, and then the preparation of monoclonal antibody in mice, which takes about two or three months. If the prepared antibody performance is not good, it needs to be prepared again, which takes another two or three months.

The joint detection

The COVID-19 Testing nucleic acid / antibody / antigen has different focuses and can not be substituted for each other. Multiple detection methods are combined and complement each other. Combine molecular biology and immune level detection to give play to their respective advantages and improve sensitivity and specificity. It can effectively shorten the detection window period, improve the positive detection rate, and provide double guarantee for all possible risk groups.

reference：Zhengtu Li，Yongxiang Yi et al. Development and clinical application of a rapid IgM‐IgG combined antibody test for SARS‐CoV‐2 infection diagnosis. J Med Virol.2020；1-7

Sample collection swab :How much do you know about nucleic acid testing

Posted on 2021年9月10日2022年3月22日 by Dr. Lee

Sample collection swab:How much do you know about nucleic acid testing

The spread of the covid-19 is continuing worldwide. Although the global scientific and medical circles are making every effort to fight the epidemic, it is difficult to predict how the epidemic will develop in the future, and its impact on social development has appeared in many aspects.

Currently, COVID-19 cases are over 220 million.

In order to fully control covid-19, the general screening of local areas shall be carried out if necessary.

After identifying the detection object, how to detect it?

1、 What specimen to choose?

According to the recommendations of the American infectious diseases association, the following specimens were used:

Nasopharyngeal swab
Middle turbinate swab
Anterior nostril swab
saliva
Anterior nostril + oropharyngeal swab
Alveolar lavage fluid
Anal swab

The sensitivity of simple oropharyngeal swab may not be enough, so it is relatively easy to miss diagnosis.

The sensitivity of alveolar lavage fluid is the highest, but it is obviously not suitable for universal screening.

Nasopharynx swabs and other operations should also be standardized.

Improper operation may make the quality of collected samples not high, thus increasing the risk of missed diagnosis.

2、 Select the time of detection

It is very important for COVID-19 to measure RNA and choose the right time. One analysis included 7 studies, including 2 unpublished reports, to evaluate the detection efficiency of RT-PCR at different time points after exposure to virus :

On the day of exposure to the virus, the possibility of detecting viral RNA is almost zero;

On the fifth day after exposure, that is, the first day after infection, the detection probability was 62%

About the 8th day after exposure, i.e. the 4th day after infection, the probability of detection was 80%

On the 21st day after exposure, i.e. the 17th day after infection, the detection probability was 34%

In conclusion, exposure to COVID-19 may require multiple tests to avoid missed diagnosis. However, it is not recommended to repeat the test within 24 hours of the previous test; The interval between two tests shall be at least 24 hours.

After 28 days of exposure to the virus, if the infection has not been diagnosed, it is not necessary to continue the detection; At this time, it is almost certain that it is not infected.

Nucleic acid detection throat swab sampling process

The COVID-19 nucleic acid was novel coronavirus, which was collected from sputum or lower respiratory tract by real-time fluorescent RT-PCR. If positive, the new coronavirus could be diagnosed. This is the basis for the diagnosis of new type of pneumonia. In addition to detecting the nucleic acid of the virus, it can also detect whether the virus in the specimen is highly homologous with New Coronavirus. If so, it can be diagnosed as New Coronavirus pneumonia. The virus is highly infectious and has the characteristics of human to human transmission, but the virus is sensitive to temperature and sunlight and ultraviolet rays.

Sample collection, nasopharyngeal swab sampling

Sample collection, Oropharyngeal swab sampling

The flocked swab is the best raw material for sampling swabs.

reference

1，Infectious Diseases Society of America Guidelines on the Diagnosis of COVID-19, updated December 23, 2020. https://www.idsociety.org/practice-guideline/covid-19-guideline-diagnostics/ (Accessed on January 14, 2021).

2，Kucirka LM, Lauer SA, Laeyendecker O, et al. Variation in False-Negative Rate of Reverse Transcriptase Polymerase Chain Reaction-Based SARS-CoV-2 Tests by Time Since Exposure. Ann Intern Med 2020; 173:262.

np swab vs op swab

Posted on 2021年8月23日2022年3月22日 by Dr. Lee

Since the end of July, COVID-19 has been scattered everywhere. Universal COVID-19 nucleic acid detection has been opened in many parts of the world. After several rounds of nucleic acid sampling and testing, many citizens have some doubts. What are the differences between nasopharyngeal test and oropharyngeal swab sampling?

What are the ways of sampling the nucleic acid of the SARS-CoV-2?

nucleic acid samples collected through the nasal cavity are called “nasopharyngeal swabs”. Samples collected through the mouth are called “oropharyngeal swabs”. Both are the main ways to collect samples from COVID-19 nucleic acid detection. In addition, there are deep expectoration fluid, nasopharyngeal or respiratory tract extract, bronchial lavage fluid, and alveolar lavage fluid.

how to choose nasopharyngeal swabs and oropharyngeal swabs?

Whether to choose nasopharyngeal swabs or oropharyngeal swabs, mainly follows the following principles: first, according to the eighth edition of the prevention and control plan and the second edition of COVID-19 nucleic acid testing manual, the first choice is to collect nasopharyngeal swabs while collecting nucleic acid samples. Secondly, asymptomatic infected persons, entry personnel and close contacts should collect nasopharyngeal swabs during isolation observation; Third, due to the relatively simple operation of oropharyngeal swabs, more oropharyngeal swabs should be collected when nucleic acid detection is carried out in low-risk areas.

why should nasopharyngeal swabs be collected first?

The study shows that the detection rate of COVID-19 nucleic acid in nasopharyngeal swabs is higher than that in oropharyngeal swabs, because the nasopharyngeal cavity is relatively closed and the virus is easier to accumulate. Secondly, the sampler can stand behind the patient’s side. The patient only needs to expose his nostrils, and there is basically no pharyngeal reflex. The exposure risk of the sampler is lower and safer than that of the oropharyngeal swab. However, whether it is oropharyngeal swab or nasopharyngeal swab, the key is that the collection action should be standardized, in place and meet the standards. As long as the collection is standardized, both methods can achieve the expected detection purpose.