Abstract
Dengue fever is a major global public health issue, with approximately 390 million
cases of dengue virus infection annually. Generally, individuals infected with the dengue
virus show no symptoms; however, some develop clinical symptoms, categorized into
dengue fever, which is mild, and dengue hemorrhagic fever, characterized by rapid
plasma leakage that can be fatal without prompt and appropriate treatment. The cause
of dengue fever is infection with the dengue virus, a member of the Flavivirus genus,
which has four serotypes: 1, 2, 3, and 4, and is transmitted by Aedes mosquitoes. There
is currently no cure or reliable preventive method for dengue fever, and available
vaccines offer limited effectiveness while posing risks for individuals who have never
been previously infected with the dengue virus. Dengue virus infection diagnosis is
typically done using a blood sample, although other specimens such as saliva or urine
can be used to detect the virus and antibodies specific to dengue virus. Recently, "oral
fluid" or saliva has been used to detect antibodies against various pathogens, including
HIV and hepatitis viruses (HCV, HAV, HBV). We have investigated whether it could replace
blood sampling. While oral fluid samples were not effective in detecting viral genetic
material or NS1 protein, they were able to detect dengue antibodies (IgM and IgG), and
the antibody levels in oral fluid were found to correlate with those in blood samples.
Our findings show that detecting dengue virus antibodies (IgM/IgG) in oral fluid has high
sensitivity and specificity (97.9% and 83.0%, respectively). Additionally, IgG antibodies
were detectable up to 1–2 months after fever onset in 59.0% of cases. This study
suggests that oral fluid can potentially be used to detect antibodies as an alternative to
blood sampling, which may be useful for identifying asymptomatic cases during
outbreaks, monitoring large child populations, or screening the effects of vaccination.
