RT-PCR test positivity rate rises at alarming rate in Ghaziabad

Ghaziabad A large number of patients testing negative during rapid antigen testing have started testing positive during a follow up RT-PCR test in Ghaziabad, setting

Ghaziabad A large number of patients testing negative during rapid antigen testing have started testing positive during a follow up RT-PCR test in Ghaziabad, setting off alarm bells among district healthcare officials.

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According to health officials, the primary positivity rate for Covid-19 during antigen testing is about 3.52%, while subsequent positivity through RT-PCR tests is about 10.07% so far in the district.

The Ghaziabad district at present has a total of 2,205 Covid-19 cases,and has witnessed 62 deaths. At least 843 people have been discharged from various hospitals and the district has 1,118 active cases, the highest across Uttar Pradesh as on July 4. The district was initially provided with 8,000 antigen kits on June 24, 11,000 more kits being provided for enhanced testing which started two days later.

“So far, we have done 7,063 antigen sampling and 249 of these results were found positive, which puts the positivity rate at around 3.52% . When we took samples of 6,814 instances for getting confirmation of true negative, we found that 140 samples out of 1390 reports received so far, tested positive through RT-PCR test. The positivity rate jumped to about 10.07% , which is alarming,” said Dr NK Gupta, chief medical officer.

Approved by the Indian Council of Medical Research (ICMR), antigen tests look for specific protein associated with the Sars-Cov-2 virus, the pathogen that causes Covid-19.

The new test, developed by a South Korean company, is highly specific (99.3% to 100%) — meaning a positive result on the test is a “true positive” and does not need any confirmatory test.

The sensitivity is between 50.6% to 84% depending on the viral load, meaning those who test negative might still have the infection and are advised to go for a test through the more reliable RT-PCR method if they show symptoms of the disease.

“A person testing negative during antigen testing isn’t necessarily virus-free. The subsequent sampling result (for finding true negative) shows that 10.07% persons are testing positive through the RT-PCR test. The infection, though mild, is a cause of concern if every 10 out of 100 tests that we do turn positive. The pending 5,424 samples that have gone for testing may have a similar positivity rate,” CMO added.

The antigen testing at present is taken up primarily in trans-Hindon areas, which have a major share of containment zones.

“We have also asked 12 teams to check the identity proofs and mobile number of persons whose xx tests are being done. The teams have been told to note down the ID proof numbers as well as ask the person to call them in order to verify his number. This is because we are not able to reach about 5 to 10% people whose tests were done. Their mobiles are either switched off or numbers found to be incorrect,” CMO added.

With rise in number of cases, district officials are also now scampering to open up one more L1 hospital at IMS, Dasna, which is will have 325 beds. The district officials earlier this week had inaugurated a 250-bed Divyajyoti Hospital at Niwari and a Covid facility at SRM College campus, with 300 beds.

According to the figures available with the state control room, the district till May 31 had 305 cases. The figures went up to 1,615 cases by June 30. During the first four days of July, at least 408 more cases have been added to the tally, with an average of little over 100 cases per day.

The discharge rate is still on the lower side and this is the reasons why the health department is keen on opening more L1 Covid hospitals. The officials expect that after implementation of the new discharge guidelines, the discharge rate will rise.

As per the new discharge guidelines issued on June 19, if an asymptomatic patient shows no symptoms, he/she can be discharged without undergoing any tests on the tenth day from the date of admission. But, such patients will have to remain in home quarantine for seven days after discharge from hospital.

According to officials, the recovery rate of L1 category patients ranges from 8-16 days while L2 and L3 patients, having moderate to critical conditions, need full recovery before they can be discharged.

“With rise in rate of positivity, there is another issue which has cropped up. Since Unlock 1, there have been a huge number of people going to different markets, workplace among other places. So, finding the source of infection is getting complicated with a rise in number of cases,” a health department official said.

Earlier, there was major contribution of cross-border infection coming in from Delhi.

“But now, cases are being found locally as people move about freely,” said the officer from the health department.