Influenza / COVID-19 Antigen Rapid Test Kit (A254380)

Influenza / COVID-19 Antigen Rapid Test Kit uses immunochromatography to qualitatively detect the presence of Influenza virus Type A, Influenza virus Type B, and SARS-CoV-2 virus (COVID-19) antigens in swabs from patients with respiratory infection symptoms. This multi-diagnosis kit can quickly distinguish the two diseases, which have similar respiratory symptoms with a high transmission rate. The kit is easy to use in the field without additional medical equipment.

Each test device consists of two seperate nitrocellulose membrane strips. The strip for detecting SARS-CoV-2 antigens has anti-SARS-CoV-2 monoclonal antibodies coated to it at the test "T" position, and also contains free anti-SARS-CoV-2 monoclonal antibodies conjugated to a reporter at the sample end. When samples are added to the well, the SARS-CoV-2 antigens in the sample are bound by the conjugated antibodies and these migrate across the test strip to the test area, where they are captured by the coated antibodies. The antibody-antigen-antibody-reporter complex results in a visible line at the "T" position if the result is positive for SARS-CoV-2. Free Nus-gold conjugates at the sample end, and coated anti-Nus monoclonal antibodies at the test end similarly result in a visible line at the control "C" position when a sample is added, to indicate a valid test result.

The strip for detecting Influenza virus antigens has Mouse anti-Influenza A monoclonal antibodies coated to it at the test "T1" position, Mouse anti-Influenza B monoclonal antibodies coated to it at the test "T2" position, and free Mouse anti-Influenza A monoclonal antibodies and Mouse anti-Influenza B monoclonal antibodies conjugated to reporters at the sample end. When samples are added to the well, the Influenza antigens in the sample are bound by the conjugated antibodies and these migrate across the test strip to the test area, where they are captured by the coated antibodies. The antibody-antigen-antibody-reporter complexes result in a visible line at the "T1" position if the result is positive for Influenza Type A antigens, and at the "T2" position if the result is positive for Influenza Type B antigens. Visible lines at both the "T1" and "T2" positions indicate a positive result for both Type A and Type B Influenza. Goat anti-Mouse IgG antibodies coated at the "C" position also bind the migrating conjugated antibodies, resulting in a visible line at the "C" position when a sample is added, to indicate a valid test result.

A negative result in each test is indicated by one line, in the control region. If the control line fails to appear then the results are invalid and additional testing is required.

Influenza / COVID-19 Antigen Rapid Test Kit comes in packs of 25 tests and contains:

• 25 x Test cassette
• 2 x Extraction solution
• 25 x Extraction tube
• 25 x Disposable dropper cap
• 25 x Sterilized nasopharyngeal swabs (for sample collection)
• 25 x Sterilized oropharyngeal swabs (for sample collection (optional))
• 1 x Instructions for use

Background:

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), previously known by the provisional name 2019 novel coronavirus (2019-nCoV), is a positive-sense single-stranded RNA virus, which is closely related to the SARS virus. It is contagious in humans and is the cause of the ongoing coronavirus outbreak, an epidemic of coronavirus disease 2019 (COVID-19) that has been designated a Public Health Emergency of International Concern by the World Health Organization (WHO). Those affected may develop a fever, dry cough, fatigue, and shortness of breath. A sore throat, runny nose, or sneezing is less common. Cases can progress to pneumonia and multi-organ failure. The infection is spread from one person to others via respiratory droplets produced from the airways, often during coughing or sneezing. Time from exposure to onset of symptoms is generally between 2 and 14 days, with an average of 5 days. The standard method of diagnosis is by reverse transcription polymerase chain reaction (rRT-PCR) from a nasopharyngeal swab or sputum sample, with results within a few hours to 2 days. Antibody assays can also be used, using a blood serum sample, with results within a few days. The infection can also be diagnosed from a combination of symptoms, risk factors, and a chest CT scan showing features of pneumonia. Rapid antigen diagnostic test kits have now been developed, such as this Influenza / COVID-19 Antigen Rapid Test Kit.

Influenza, commonly known as "the flu", is an infectious disease caused by an influenza virus. Symptoms can be mild to severe. The most common symptoms include: high fever, runny nose, sore throat, muscle pains, headache, coughing, sneezing, and feeling tired. These symptoms typically begin two days after exposure to the virus and most last less than a week. The cough, however, may last for more than two weeks. In children, there may be diarrhoea and vomiting, but these are not common in adults. Complications of influenza may include viral pneumonia, secondary bacterial pneumonia, sinus infections, and worsening of previous health problems such as asthma or heart failure. Three of the four types of influenza viruses affect people, Type A, Type B, and Type C. Type D has not been known to infect people, but is believed to have the potential to do so. Usually, the virus is spread through the air from coughs or sneezes; this is believed to occur mostly over relatively short distances. It can also be spread by touching surfaces contaminated by the virus and then touching the mouth or eyes. A person may be infectious to others both before and during the time they are showing symptoms. The infection may be confirmed by testing the throat, sputum, or nose for the virus. Influenza spreads around the world in a yearly outbreak, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths. Death occurs mostly in the young, the old, and those with other health problems. Pandemics are less frequent. Influenza A viruses are negative-sense, single-stranded, segmented RNA viruses. The several subtypes are labelled according to an H number (for the type of hemagglutinin) and an N number (for the type of neuraminidase). There are 18 different known H antigens (H1 to H18) and 11 different known N antigens (N1 to N11). Influenza virus B is a genus in the virus family Orthomyxoviridae. The only species in this genus is called Influenza B virus. Influenza B viruses are only known to infect humans and seals, giving them influenza. This limited host and range is apparently responsible for the lack of Influenza virus B-caused influenza pandemics in contrast with those caused by the morphologically similar Influenza virus A as both mutate by both antigenic drift and reassortment.

Clinical Performance:

SARS-CoV-2: 90% sensitivity (27/30) and > 98% specificity (98/100).
130 patients’ samples were collected under IRB regulations and tested with the Influenza / COVID-19 Antigen Rapid Test Kit, with results confirmed with a RT-PCR kit (Korean FDA-EUA approved).

Influenza A: 100% sensitivity (53/53) and 96.2% specificity (229/238).
Influenza B: 98.4% sensitivity (61/62) and 94.8% specificity (217/229).
291 patients’ samples were collected under IRB regulations and tested with the Influenza / COVID-19 Antigen Rapid Test Kit, with results confirmed with a RT-PCR kit (Korean FDA-EUA approved).

Limit of Detection:

SARS-CoV-2 Antigen: 2.87 x 10³ TCID₅₀/ml (heat-inactivated SARS-CoV-2 culture fluid).
Influenza A/B Antigens: 19.53 HA/ml for Influenza A (H1N1), 20.02 HA/ml for Influenza A (H3N2), 5.78 HA/ml for Influenza B (HongKong/5/72).

Hook Effect:

The Hook effect is an immunologic phenomenon in which the ability of antibodies to form immune complexes is sometimes impaired when concentrations of an antibody or an antigen are very high, resulting in false negatives or inaccurately low results in immunoassays.

No Hook effect was observed at 1.15 x 10⁷ TCID₅₀/ml or at 1,000 ug/ml of nucleoprotein of SARS-CoV-2.
No Hook effect was observed at 2.0 x 10⁴ HA/ml for Influenza A and at 4.1 x 10⁴ HA/ml for Influenza B.

Cross-Reactivity:

For the SARS-CoV-2 test, there was cross-reactivity of SARS-CoV-1. However, there was no cross-reactivity with: MERS-coronavirus, Human coronavirus (NL63), Human coronavirus (229E), Human coronavirus (OC43), Human Adenovirus type 1, Human Adenovirus type 3, Human Adenovirus type 8, Human Adenovirus type 18, Human Adenovirus type 23, Human Adenovirus type 7, Human Adenovirus type 5, Human Adenovirus type 11, Human Parainfluenza virus type 1, Human Parainfluenza virus type 2, Human Parainfluenza virus type 3, Human Parainfluenza virus type 4, Human Rhinovirus type 1, Human Rhinovirus type 14, Human Rhinovirus type 42, Human Metapneumovirus, Respiratory syncytial virus-A, or Respiratory syncytial virus-B.

For the Influenza A/B test, there was no cross-reactivity with: SARS-CoV-1, SARS-CoV-2, Human Adenovirus type 1, Human Adenovirus type 2, Human Adenovirus type 3, Human Adenovirus type 8, Human Adenovirus type 18, Human Adenovirus type 23, Human Adenovirus type 7, Human Adenovirus type 5, Human Adenovirus type 11, Measles virus, Human Parainfluenza virus type 1, Human Parainfluenza virus type 2, Human Parainfluenza virus type 3, Human Parainfluenza virus type 4, Respiratory syncytial virus-A, Respiratory syncytial virus-B, Human Rhinovirus type 1, Human Rhinovirus type 14, Human Rhinovirus type 42, Human Metapneumovirus, Escherichia coli, Staphylococcus epidermidis, Streptococcus pneumoniae, Streptococcus pyogenes, or Streptococcus salivarius.

Interfering Substances:

No interference seen in the SARS-CoV-2 test and in the Influenza test, for both Influenza A and Influenza B, with: Whole blood, Mouth wash, Phenylephrine, Acetylsalicylic acid, Beclomethasone, Benzocaine, Flunisolide, Guaiacol glyceryl ether, Menthol, Oxymetazoline, Tobramycin, Zanamivir, Oseltamivir phosphate, or mucus.

Warnings:

Influenza / COVID-19 Antigen Rapid Test Kit is a primary test for SARS-CoV-2 and Influenza virus (Type A and Type B) antigens and is for professional use only, and not for at home testing.

For in vitro diagnostic use only. Do not use after expiry date. Do not eat, drink, or smoke in the area where the specimens or kits are handled. Do not use test if pouch is damaged. Handle all specimens as if they contain infectious agents. Observe established precautions against microbiological hazards throughout the procedure and follow the standard procedures for proper disposal of specimens. The used test should be discarded according to local regulations. Keep out of the reach of children. Wear disposable powder-free gloves, face mask, and lab coats. Do not re-use the test device.