Indore: Amid increasing number of positive patients, experts believe that a sample can be tested negative even after being ‘positive’ due to the improper sampling or over the timing of samples taken.
Doctors named the phenomenon as ‘False Negative’ and vice-versa are known as ‘False Positive’. There are many reasons due to which the samples tested opposite but the percent of such cases is less than equal one percent.
WHAT DOCTORS SAY
“There are various reasons due to which a positive sample can be tested negative. It is not due to anyone’s fault but due to the non-cooperation of the patient whose samples are taken. There is no fault in testing or reporting of the samples,” HoD of Respiratory Medicine Dr Salil Bhargava said.
He said that the percent of such samples is 1 percent of the total samples.
Citing an example of false positive, Dr Bhargava said the 16-year-old girl who was tested positive again after being negative might be one of the same. “Some patients test positive even after being negative due to the remaining dead cells. RT-PCR test finds the positive and negative of the patients but not the culture,” he said adding “Symptoms of the patients should be treated regardless of being positive or negative.”
Meanwhile, pulmonologist of Choithram Hospital Dr Gaurav Gupta said chance of false negative are more than false positive samples.
“One of the reasons may be the timing of samples taken as if it is taken within five days of being infected, concentration of virus remain less which gives a negative report. Similarly, improper sampling too may lead to the same. Chances of those turned negative become positive again is negligible as antibodies developed in them and it can take place only when virus mutates,” Dr Gupta said.
Dentist of Government College of Dentistry Dr Kuldeep Rana said, “Our team has collected over 5,000 samples and sometimes patients do not cooperate in giving samples. We use to alert them before taking samples as they feel like vomit at the time of sampling which also affect the sample report.”
Over 500 samples were rejected in testing in city so far due to these reasons including improper sampling.