When to Use dengue ns1 antigen？

NS1 Detection

What is the test?

• NS1 tests detect the non-structural protein NS1 of dengue virus. This protein is secreted into the blood during dengue infection.
• NS1 tests have been developed for use in serum. Most of these tests use synthetically labeled antibodies to detect dengue NS1 protein.

How should it be used and at what time during infection?

• NS1 is detectable during the acute phase of dengue virus infections. NS1 tests can be as sensitive as molecular tests during the first 0-7 days of symptoms. After day 7, NS1 tests are not recommended.
• A positive NS1 test result is indicative of a dengue infection but does not provide serotype information. Knowing the serotype of the infecting virus is not necessary for patient care; however, if serotype information is needed for surveillance purposes, the sample should be tested by NAT.
• Though studies show that NS1 can be found in whole blood or plasma, most NS1 tests have been developed and evaluated in serum samples. While combined testing with a NS1 and IgM antibody test can usually provide a diagnostic result during the first 1-7 days of illness, a second, convalescent phase specimen should be obtained and tested for IgM when both antigen and antibody tests are negative.

Specimen types

• Serum

Interpretation of results

• A positive NS1 test result confirms dengue virus infection without providing serotype information.
• A negative NS1 test result does not rule out infection. People with negative NS1 results should be tested for the presence of dengue IgM antibodies to determine possible recent dengue exposure.

Availability

Dengue NS1 tests are available as commercial diagnostic kits, a limited number are cleared by the US Food and Drug Administration. Some public health and commercial laboratories use these tests.

Are you interested in learning more about dengue ns1 antigen? Contact us today to secure an expert consultation!

Dengue is a mosquito-borne viral disease that has established itself globally in both endemic and epidemic transmission cycles. While diagnostic decision-making for dengue is often guided by clinical judgement, definitive laboratory tests, including rapid point-of-care tests, have many advantages in the primary care setting. These include providing epidemiological data and diagnostic clarity for atypical cases, as well as contributing to patient education and compliance. This article discussed the types of diagnostic methods for dengue, when to use them and the appropriateness of each test. Viral detection diagnostic methods such as NS1 antigen assays are generally used within the first week of illness onset, whereas dengue serology testing is most appropriate after that time frame. Locally available rapid point-of-care tests, which include both assays in one convenient test kit, can enhance dengue diagnosis in an endemic setting.

Lisa, a 35-year-old woman, visited you for the first time, complaining about severe aches in her shoulders, hips and knee joints. She had also been feeling extremely tired for the past few days but reported no fever. You found out that her husband had been diagnosed with dengue a week before. In view of this history, you decided that it would be useful to conduct a definitive dengue diagnostic test.

In 2009, the World Health Organization (WHO) introduced a revised scheme, which resulted in a paradigm shift in the approach to dengue fever.( 1 , 2 ) The proposed scheme emphasised the early recognition of warning signs, resulting in the optimisation of triage and management decisions. The following classifications were revised: dengue without warning signs; dengue with warning signs (abdominal pain, persistent vomiting, fluid accumulation, mucosal bleeding, lethargy, liver enlargement, increasing haematocrit with decreasing platelets); and severe dengue (dengue with severe plasma leakage, severe bleeding or organ failure).( 3 )

Want more information on Multi-Drug Urine Panel? Feel free to contact us.

Dengue fever is an acute illness caused by an infection from one or more of the four serotypes of dengue viruses (DENV 1 to 4). The viruses are transmitted through the female mosquito species Aedes aegypti and, less commonly, Aedes albopictus. It is a dynamic, systemic disease with a wide clinical spectrum that includes both severe and non-severe clinical manifestations. Although the illness is usually self-limiting, for a minority of patients, dengue can cause life-threatening complications.

HOW RELEVANT IS THIS TO MY PRACTICE?

A total of 18,335, 11,286 and 13,115 dengue cases were recorded in Singapore in 2014, 2015 and 2016, respectively.(4) In 2017, however, we have seen a sustained reduction of approximately two-thirds of dengue cases in the months leading up to 22 September (cumulative total of 2,066 reported cases).(5) Project Wolbachia-Singapore is a new initiative that was started to combat dengue in the country. Male Aedes aegypti mosquitoes infected with Wolbachia (a naturally occurring bacteria) have been released in stages into the environment since October 2016. These male Wolbachia-carrying Aedes aegypti mosquitoes seek to mate with female Aedes aegypti, but the resulting eggs will not hatch (i.e. non-viable eggs) because the mating is biologically incompatible, thus leaving no offspring.(6) The subsequent reduction in dengue cases suggests that such new vector control measures have been successful.

Although the number of dengue cases has been falling, countries in Southeast Asia (such as Thailand and Malaysia) and Latin America remain prime hotspots for the disease.(7) With increasing air travel and greater mobility of both vector and human populations, the risk of imported dengue cases in Singapore is still high.(8) Locally, other mosquito-borne viruses, such as Chikungunya and Zika, also often present with similar clinical features. Some common overlapping symptoms include fever, myalgia, maculopapular exanthema, retro-orbital pain and lymphadenopathy.(9,10)

Prompt and accurate diagnosis continues to be important. The lower prevalence of dengue, however, mandates a change in our clinical approaches to febrile illnesses and a review of the use of dengue diagnostic tests. The wide spectrum of febrile illnesses and atypical dengue presentations poses a real challenge to clinicians.(11) Delayed diagnosis might lead to one or more of these unfortunate circumstances: (a) The patient will not be accorded the close vigilance required of dengue patients. (b) The patient will not be advised to monitor for danger signs. (c) The patient, who continues to be a reservoir of infection, will not be educated on vector bite prevention measures. (d) Potential dengue clusters may be missed due to a lack of epidemiological data. (e) Other unnecessary investigations, such as autoimmune markers or markers of myositis, may be ordered.

For more alcohol stripinformation, please contact us. We will provide professional answers.