AFI Rapid Kit

│ Descriptions │

 

"ImmnuneMed AFI Rapid" tests the antibodies against Hantaan and Seoul virus (Hemorrhagic fever with renal syndrome: HFRS), Orientia tsutsugamushi (Scrub typhus) and Leptospira (Leptospirosis) in the patient's plasma, serum or blood using lateral flow immunochromatographic assay. After applying diluted serum, plasma or blood onto the hole of testing device, for IgM, patient’s sample first reacts with gold conjugated anti-human IgM antibody and for IgG, with gold conjugated protein A. After that, each reactant diffuses on the membrane to the corresponding recombinant antigens marked as test lines(L, S, H). If positive, each test line turns to red color because antigen- antibody-gold conjugate complex is formed on the test line (L, S, H) respectively. AFI(Acute Febrile Illness) is urgenly required accurate early differential diagnosis and proper therapy against each different causative microorganism with similar clinical symptom.

 Using lateral flow immunochromatographic method, this AFI Rapid provides not only simultaneous differential diagnosis of 3 AFIs (HFRS caused by Hantaan and Seoul virus, Scrub typhus by Orientia tsutsugamushi and Leptospirosis by Leptospira) but also sensitive detection of each IgM and IgG antibody on this kit. Furthermore, this AFI kit is easy to handle and provides rapid interpretation of the result with no equipment. In addition, this kit is useful for the follow up study and the estimation of reinfection and residual antibody.

│ Feature │

1) Testing device: one round hole for sample applying on the white plastic cassette and two detection window for IgM and IgG. There are 4 different markings, such as C for control line, H for HFRS caused by Hantaan or Seoul virus, S for Scrub typhus by Orientia tsutsugamushi and L for Leptospirosis by Leptospira on each detection window. 2) Sample diluent: colorless liquid in the semi-transparent plastic bottle

│ Specification │

1) specimen
(1) Use serum, plasma or whole blood as specimen.
(2) Collected blood containing anti-coagulant should be used immediately or the blood kept in 2～8℃ for 3 days is possible to use.
(3) Separated serum and plasma could be used until one month if kept in 2～8℃ or 1 year if kept frozen.

2) Methods
(1) If each specimen and reagent is kept in cold storage, place it for 15~30 min at room temperature before use.
(2) After pulling out the testing cassette from the closed pouch, place it on the flat position.
(3) In case of serum or plasma, 3ul is diluted about 100 fold with 300kl sample diluent. If whole blood, take 6kl and it is diluted about 50 fold with 300kl sample diluent. After that, apply 300kl of this diluted sample to the hole. * Or when 3kl of serum or plasma, or 6kl of whole blood are directly applied to the sample pad in the hole, immediately add 7 drops of sample diluent provided.
(4) Wait for 5-10 min until the red line appears on the control line. Read and interpret the result from 10 to 20 min after applying this diluted sample.

3) Interpretation
(1) HFRS caused by Hantaan or Seoul virus
① Positive: Red lines must appear on each control (C) line of IgM and IgG in the detection windows and one or two red lines should appear on the test line, H in the windows (Fig 1. a,b,c).
② Negative: Red lines only appear on both C lines of IgM and IgG in the detection windows and no red line should appear on the test line, H (Fig 1. d).
③ Invalid: If red line does not appear from at least one out of 2 C lines, this result is interpreted as invalid, and do test again (Fig 1. e).

Fig 1. Interpretation for HFRS
(2) Scrub typhus caused by Orientia tsutsugamushi
① Positive: Red line must appear on each C line of IgM and IgG in the detection windows and one or two red lines should appear on the test line, S in the windows (Fig 2. a,b,c).
② Negative: Red lines only appear on both control lines of IgM and IgG in the detection windows and no red line should appear on the test line, S (Fig 2. d).
③ Invalid: If red line does not appear from at least one out of 2 C lines, this result is interpreted as invalid, and do test again (Fig 2. e).

 

 

 

 

a. positive b. positive c. positive d. negative e. Invalid Fig

 2. Interpretation for Scrub typhus

 (3) Leptospirosis caused by Leptospira
 ① Positive: Red line must appear on each C line of IgM and IgG in the detection windows and one or two red line should appear on the test line, L in the windows (Fig 3. a,b,c).
② Negative: Red lines only appear on both C lines of IgM and IgG in the detection windows and no red line should appear on the test line, L (Fig 3. d).
③ Invalid: If red line does not appear from at least one out of 2 C lines, this result is interpreted as invalid, and do test again (Fig 3. e).

 

 

 

3. Interpretation for Leptospirosis 4) Quality control Red lines should appear on both control lines for each testing.