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Evaluation of the Dengue NS1 Ag Strip (R) for Detection of Dengue Virus Antigen in Aedes aegypti (Diptera: Culicidae)

Environmental Health Institute, National Environmental Agency, Singapore, Singapore.
Vector borne and zoonotic diseases (Larchmont, N.Y.) (Impact Factor: 2.3). 03/2011; 11(6):789-92. DOI: 10.1089/vbz.2010.0028
Source: PubMed

ABSTRACT

Dengue fever is currently one of the most important mosquito-borne diseases that affect humans. With neither vaccines nor treatment available, prevention of the disease relies heavily on surveillance and control of mosquito vectors. In the present study, we have evaluated and showed the potential use of the Dengue NS1 Ag Strip(®) for the detection of dengue virus (DENV) in Aedes aegypti. Initial results showed that the sensitivity of the test kit in detecting DENV in wild-caught mosquitoes is comparable to that of real-time reverse transcriptase-polymerase chain reaction. The detection of naturally infected Ae. aegypti with the NS1 rapid test kit in our dengue cluster investigation further illustrates its potential use for surveillance of DENV in wild mosquito populations. The kit can easily be used in a simple field station, and minimal training is required. The results can be obtained in less than an hour. Employment of the kit in the field could help guide mosquito control operations in the prioritization of resources in controlling the transmission of DENV. In this study the potential of the kit for field surveillance of infected dengue vectors, which are epidemiologically important, has been demonstrated.

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    • "Surveillance of DENV in Ae. aegypti females is of potential interest as a means for early detection of dengue outbreaks because human DENV infections are commonly asymptomatic or " silent " (Gubler 1998, Kyle and Harris 2008), which decreases the effectiveness of dengue case surveillance to provide early warning of building outbreaks. Improved methods for detection of DENV RNA or antigen in mosquitoes (Bangs et al. 2007, Chao et al. 2007, Chen et al. 2010, Tan et al. 2011, Muller et al. 2012, Voge et al. 2013) provide new opportunities for mosquito-based DENV surveillance, and studies focusing entirely or in part on dengue patient premises have shown promise with regards to the potential for linking DENV infections in Ae. aegypti to human dengue cases in space and time (Pinheiro et al. 2005, Urdaneta et al. 2005, Garcõ´a- 886 JOURNAL OF MEDICAL ENTOMOLOGY Vol. 51, no. 4 Rejó n et al. 2008, Guedes et al. 2010, Yoon et al. 2012). "

    Full-text · Dataset · Feb 2015
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    • "Surveillance of DENV in Ae. aegypti females is of potential interest as a means for early detection of dengue outbreaks because human DENV infections are commonly asymptomatic or " silent " (Gubler 1998, Kyle and Harris 2008), which decreases the effectiveness of dengue case surveillance to provide early warning of building outbreaks. Improved methods for detection of DENV RNA or antigen in mosquitoes (Bangs et al. 2007, Chao et al. 2007, Chen et al. 2010, Tan et al. 2011, Muller et al. 2012, Voge et al. 2013) provide new opportunities for mosquito-based DENV surveillance, and studies focusing entirely or in part on dengue patient premises have shown promise with regards to the potential for linking DENV infections in Ae. aegypti to human dengue cases in space and time (Pinheiro et al. 2005, Urdaneta et al. 2005, Garcõ´a- 886 JOURNAL OF MEDICAL ENTOMOLOGY Vol. 51, no. 4 Rejó n et al. 2008, Guedes et al. 2010, Yoon et al. 2012). "
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    ABSTRACT: Surveillance of dengue virus (DENV) in Aedes (Stegomyia) aegypti (L.) females is of potential interest because human DENV infections are commonly asymptomatic, which decreases the effectiveness of dengue case surveillance to provide early warning of building outbreaks. Our primary aim was to examine if mosquito-based virological measures—monthly percentages of examined Ae. aegypti females infected with DENV or examined homes from which at least one DENV-infected Ae. aegypti female was collected—are correlated with reported dengue cases in the same or subsequent months within study neighborhoods in Mérida City, México. The study encompassed ≈30 neighborhoods in the southern and eastern parts of the city. Mosquitoes were collected monthly over a 15-mo period within study homes (average of 145 homes examined per month); this produced ≈5,800 Ae. aegypti females subsequently examined for DENV RNA. Although monthly dengue case numbers in the study neighborhoods varied >100-fold during the study period, we did not find statistically significant positive correlations between monthly data for mosquito-based DENV surveillance measures and reported dengue cases in the same or subsequent months. Monthly average temperature, rainfall, and indoor abundance of Ae. aegypti females were positively correlated (P ≤ 0.001) with dengue case numbers in subsequent months with lag times of 3‐5, 2, and 1‐2 mo, respectively. However, because dengue outbreak risk is strongly influenced by serotype-specific susceptibility of the human population to DENV, the value of weather conditions and entomological indices to predict outbreaks is very limited. Potential ways to improve the sensitivity of mosquito-based DENV surveillance are discussed.
    Full-text · Article · Jul 2014 · Journal of Medical Entomology
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    • "Some commercial kits for the NS1 detection approach have been reported to detect DENV in Ae. aegypti mosquitoes. For instance, Tan et al. [31] demonstrated that the Dengue NS1 Ag Strip was efficient in detecting all DENV serotypes and was also able to detect DENV-2 up to 10 dpi when mosquitoes were stored at −80°C. DENV detection in Ae. aegypti mosquitoes was more efficient with the NS1 antigen than RT-PCR and virus isolation, but mosquitoes were infected by intrathoracic injection [30]. "
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    ABSTRACT: Surveillance is a critical component of any dengue prevention and control programme. Herein, we investigate the efficiency of the commercial kit Platelia Dengue NS1 Ag-ELISA to detect dengue virus (DENV) antigens in Aedes aegypti mosquitoes infected under laboratory conditions. Under insectary conditions, four to five day-old mosquitoes were orally challenged with DENV-2 titer of 3.6 x 105 PFU equivalent/ml, incubated for 14 days and then killed. At ten time-points following mosquito death (0, 6, 12, 24, 72, 96, 120, 144 and 168 h), i.e., during a one-week period, dried mosquitoes were comparatively tested for the detection of the NS1 antigen with other methods of detection, such as qRT-PCR and virus isolation in C6/36 cells. We first observed that the NS1 antigen was more effective in detecting DENV-2 in Ae. aegypti between 12 and 72 h after mosquito death when compared with qRT-PCR. A second round involved comparing the sensitivity of detection of the NS1 antigen and virus isolation in C6/36 cells. The NS1 antigen was also more effective than virus isolation, detecting DENV-2 at all time-points, i.e., up to 168 h after mosquito death. Meanwhile, virus isolation was successful up to 96 h after Ae. aegypti death, but the number of positive samples per time period presented a tendency to decline progressively over time. From the 43 samples positive by the virus isolation technique, 38 (88.4%) were also positive by the NS1 test. Taken together, these results are the first to indicate that the NS1 antigen might be an interesting complementary tool to improve dengue surveillance through DENV detection in dried Ae. aegypti females.
    Full-text · Article · Apr 2014 · Parasites & Vectors
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