POST TIME: 24 August, 2019 00:00 00 AM / LAST MODIFIED: 24 August, 2019 02:39:10 AM
NS1 test not foolproof to detect dengue
NS1 test may fail to come up with proper diagnosis in 10-20 per cent of dengue cases
Md Habibulla, Dhaka

NS1 test not foolproof to detect dengue

Guardians tend to ailing children suffering from dengue fever at National Hospital in the capital yesterday. With the passage of time, parents are becoming overtly concerned about the mosquito-borne disease as children have so far been the worst sufferers. Focus Bangla Photo

“I started suffering from high fever and muscle pain after getting up in the morning on August 12. A day later, I became very sick and visited a physician. The doctor suggested that I go for an NS1 antigen (nonstructural protein 1) test and complete blood count (CBC) for dengue. The NS1 test report, however, was negative for dengue and it showed my platelet count was two lakh,” said Shohag, a job holder at a private firm. “But after two days, I again came down with high fever and suffered from anal bleeding. After that, I again got the platelet count tested and found it had gone below 80,000. Then, the doctors advised me to get admitted to a hospital. However, due to lack of available beds at the hospitals, I started undergoing treatment in my home as per the doctor’s advice. Finally, after eight days, I was cured of dengue,” he added.

Similarly, 13-year-old Mahjabin Maisha came down with high fever last week. Her parents took her to a clinic for NS1 test, but the report came out negative for dengue. Mahjabin took some medicines after visiting a doctor and the fever came down. But a day later, she suffered various complications and was admitted to a private hospital. Tests revealed that her platelet count was below 10,000 and water had frozen in her liver and lungs. “My daughter was suffering from high fever. When we got her tested for NS1, it was negative. But a day later, the CBC test showed that her platelet count had gone down to 8,000. Later, we admitted her to a hospital,” Mahjabin’s mother, Nazma Begum said. The cases of Shohag and Mahjabin are examples that dengue is not always detected by the NS1 test.

According to experts, the NS1 test can fail to come up with

a proper diagnosis in 10 to 20 per cent of dengue cases. The doctors should focus on the symptoms to detect the disease, they advised.

They suggested that research on whether the dengue virus was changing or not could help in this regard.

“The dengue virus can change its pattern. This is why in some cases the NS1 test could be negative. Also, a new strain of virus can emerge that is yet to be identified,” said Dr Ahmedul Kabir, secretary-general of Society of Medicine.

He said poor quality of test kits, labs and unskilled technician can also affect the results of the NS1 test. “I would advise a person to consult a doctor and not take medicines on one’s own,” he added. Professor Dr Saif Ullah Munshi, chairman of the virology department at Bangabandhu Sheikh Mujib Medical University (BSMMU), also said that poor quality of NS1 kit could show negative result even if a person was having all the symptoms of dengue.

He advised people to get the CBC test done if the NS1 result came negative. “I also urge people not to picnic,” he added. According to the World Health Organization (WHO), 45 per cent of the reports from the NS1 rapid test are negative. Dr Murad Hossain, assistant professor of Dhaka Medical College Hospital, suggested that people should visit a medicine specialist if anyone’s NS1 test result came out negative despite having all the symptoms of dengue. According to the Directorate-General of Health Services (DGHS), the number of recorded cases in the first eight months of this year has hit 61,038 and the death toll is 47. The unofficial tally, however, has put the toll at 108. Meanwhile, 1,446 dengue patients were admitted to different hospitals across the country in the past 24 hours.