Communicable Diseases

Dengue/DHF

Dengue Bulletin Volume 24, December-2000

Evaluation of Commercial Pathozyme Dengue IgM and IgG Tests for Serodiagnosis of Dengue Virus Infection

By

Do Quang Ha, Cao Minh Thang, Tran Ton, Vu thi Que Huong, Huynh thi Kim Loan, Hoang thi Nhu Dao and Tran thi Hue Tam

Pasteur Institute, Ho Chi Minh City, Viet Nam

Table 5. Comparison of the CPD IgG assays with the HAI and virus isolations*

*By the Chi-Squares Mantel-Haenszel, c 2 was 0.00, P =0.660.

The specificity of the CPD IgM-IgG

Forty-two single sera were taken on the day of admission from children with clinical diagnosis as measles, out of which there were 25 positives and 17 negatives by measles IgM capture-ELISA. These sera were retested with CPD IgM-IgG and the Mac-ELISA, HAI for dengue. The results are given in Table 6.

Table 6. Performance of CPD IgM and Mac-ELISA with measles sera*

*By the Chi-Squares Mantel-Haenszel, c 2 was 4.15, P =0.058

Among the 42 single sera, there were five sera having dengue antibody (³ 40 HAI units), so we discarded them and only 37 measles sera without dengue antibody were used for the specificity study of the CPD IgG.

Thirty-seven measles sera without dengue antibody were tested with CPD IgG, from which there were two false positive results and 35 negative. So, the CPD IgG is specific to dengue IgG with the rate of 94.59% (Table 7).

Table 7. Performance of the CPD IgG and the HAI with measles sera without dengue antibody

Summation

The total number of samples tested for CPD IgM and CPD IgG and their sensitivity and specificity are given below:

The CPD IgM-IgG evaluated in this report are suitable for the detection of anti-dengue IgM and IgG antibodies. They should be useful for routine dengue diagnosis, particularly in developing countries as in south-east Asia where dengue infections are prevalent. For the prevention and control of dengue, the CPD IgM and the Mac-ELISA are good tools for the early detection of dengue cases during the inter-epidemic period, or during the pre-epidemic stage, for carrying out laboratory-based active surveillance.

Conclusion

The Commercial Pathozyme Dengue IgM and IgG are reliable, sensitive and specific diagnostic tests for diagnosing primary and secondary dengue infections based on antibody responses. It should be used in laboratories to support the clinical diagnosis of dengue. The Commercial Pathozyme Dengue IgM is also a very good tool for active laboratory-based dengue surveillance with the aim of controlling dengue epidemics in the tropical and sub-tropical regions.

References

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