Table 1. Results of dengue NS1 ELISA and IgM ELISA depending on time points of the blood collection after the onset of symptoms, the patient natural history and serological status, or the cause of the disease.

	Time of sample collection (DPO)
Number of days	≤4		5 to 8		≥9
Dengue NS1 antigen and IgM capture ELISA diagnostic tests	NS1	IgM	NS1	IgM	NS1	IgM
Origin of the disease and serological status
Primary wild-type dengue infection	Posa	Neg	Pos/Neg	Pos	Neg	Pos
Secondary wild-type dengue infection	Posa	Pos/Neg	Pos/Neg	Pos	Neg	Pos
Dengue infection in CYD-TDV vaccinee	Pos	Pos/Neg	Pos/Neg	Pos	Neg	Pos
Undetected previous dengue infectionb	Neg	Pos/Neg	Neg	Pos/Neg	Neg	Pos/Neg
Recent CYD-TDV vaccinationc	Neg	Pos/Neg	Neg	Pos/Neg	Neg	Pos/Neg
Infection by a Flavivirus other than dengued	Neg	Pos/Neg	Neg	Pos/Neg	Neg	Pos/Neg

^a Several factors may generate possible suboptimal detection of NS1 (see text)

^b Asymptomatic or missed dengue infection occurring less than 3 months before testing

^c Residual dengue IgM elicited by CYD-TDV may last at least 2 months [4]

^d Flavivirus cross-reactive antibodies (in secondary infection)

Abbreviations: DPO, days post onset; IgM, immunoglobin M; Pos, Positive result; Neg, Negative result; Pos/Neg, the sensitivity of the test, the time point of serum sampling, and the serological status of the patient may affect the result