Kerala has 58 approved testing laboratories with only 26 facilities doing RT-PCR tests, considered the gold standard for detecting the novel coronavirus.

Three technicians wearing PPE take a nasal swab each from two men and one woman who are seated on chairs Image for representation/PTI
Coronavirus Coronavirus Friday, July 31, 2020 - 16:00

The reverse transcription-polymerase chain reaction or RT-PCR is the gold-standard diagnostic test for COVID-19 in India. “Yet, the number of RT-PCR tests in Kerala, as part of the ‘daily routine sample’ test has not gone up more than 10,000 most days,” noted Dr Arun NM, an internal medicine expert based in Palakkad district. Between July 27 and 28, 7,721 samples were tested as part of the Routine Sample testing, which uses RT-PCR to primarily test symptomatic patients.  

According to some health experts TNM spoke to, since Kerala is seeing a rising number of cluster cases and community transmission, it is time to expand the state’s testing capacity in terms of the number of laboratories, especially for RT-PCR tests. The number of testing facilities in Kerala, approved by the Indian Council of Medical Research (ICMR), is significantly low, they noted. 

As on July 30, Kerala had 58 ICMR-approved testing labs for RT-PCR, TrueNAT and CB-NAAT (Cartridge Based Nucleic Acid Amplification Test). Of the 58 labs, 27 are government labs, while 31 are private labs. For RT-PCR tests, the state has 18 government centres and eight private laboratories. 

However, over the last two months, the number of labs getting added to the list has been minimal. For example, between May 28 and July 5, only two government and private labs each were added for RT-PCR tests. In a marginal increase, two more government labs and one private laboratory were approved for RT-PCR between July 5 and July 29. 

Some attributed the delay in government and private labs getting approval from ICMR as one possible reason. However, Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST) in Thiruvananthapuram, which has been designated by ICMR to validate and approve labs for testing in Kerala, said that if the labs satisfy all the requirements as per the basic list, it takes only a few days to get approval. 

“There are times when approval was obtained within a day itself. All the processes for the recommendation process are expedited in nature. Since private labs require NABL (National Accreditation Board for Testing and Calibration Laboratories) accreditation for the COVID-19 testing, and if there are non-conformities, it will lead to delay. Once accreditation is obtained, we make sure that there is no further delay,” said Dr Srinivas of SCTIMST,  who is in charge of lab mentoring and facilitating approvals for Kerala.

According to Dr Abraham Varghese, President, Indian Medical Association (IMA) Kerala, 58 testing labs, especially 26 for RT-PCR, are not enough to cover the entire state. 

With a population density of 550 per square kilometre, Tamil Nadu has 119 labs. Kerala, which has a population density of 860 per square kilometre, has 58 labs.

“So, if the density of population is high in Kerala, the number of labs definitely has to increase. Unless we do more testing, we cannot tell how many positive cases are there, especially for containment zones,” said Dr Abraham.   

However, Dr Mohammed Asheel, who is part of the state’s COVID-19 task force, told TNM that the test per million is not a scientific evaluation to determine the test adequacy. “According to epidemiological analysis, we cannot test the entire population to understand test adequacy. Even if we test the entire population, we would have to sift through them again the following week,” he pointed out. 

“So how do we know if we are testing appropriately? For that, the effective indicator is the test positivity rate. Test positivity rate in Kerala is between 2% and 3%, that is, if we do 100 tests among individuals suspected to have COVID-19, only two will turn positive,” he explained.   

Delayed results 

However, health experts factored in the turnaround time to receive the test results of an RT-PCR test to explain why Kerala needs to expand its testing facilities. 

“Health workers working in the containment zones definitely need to be tested more, and hence, sentinel testing, too, needs to go beyond the existing daily tests (4,400 per day). To increase the testing, we need to increase the testing centres; it has to be around 100 facilities, otherwise, we might not be able to cover the entire population of health workers,” elucidated Dr Abraham. 

Many also pointed out that the testing centres, especially the government labs, are giving the results after a delay of five or six days. The person may have interacted with others, possibly exposing them to the coronavirus during the six-day period. 

“RT-PCR is always the best and first option if the turnaround time is within 24 hours. For the results to return within 24 hours or even 48 hours, the state should increase the labs and thereby quickly identify positive cases and isolate or treat the individual,” said Dr Arun, adding that the state needs more private labs for RT-PCR testing. 

Ramping up testing facilities

Kerala’s neighbouring state, Tamil Nadu, which has recorded the second-highest number of COVID-19 cases so far in India, at 2,34,114, significantly increased testing by rapidly adding more testing facilities. As of July 30, Tamil Nadu has a total of 120 ICMR-approved testing labs (59 government labs and 61 private labs). 

A comparison between the two states from June 11 to July 10 shows that Kerala was lagging in adding new COVID-19 testing facilities. While Kerala added one government and one private lab in a span of 30 days, Tamil Nadu managed to add three government labs and 10 private labs. 

Tamil Nadu increased its number of labs for RT-PCR at a time when the number of COVID-19 cases was rising in the state. From 34,914 COVID-19 cases on June 9, the number rose to 1,30,261 on July 10, a surge of a whopping 273%. Tamil Nadu has also tested the highest number of samples in India till date, at 25,36,660. 

In comparison, Kerala has done over 6.77 lakh tests. Over 3.76 lakh samples tested are from the routine testing carried out.  

Despite the numbers, experts said Kerala is in a much better place than other south Indian states as authorities were able to initially keep the disease and the positivity rate under control. 

“However, overall the RT-PCR testing capacity is limited in Kerala. We are now doing mostly antigen tests, while both Andhra Pradesh and Tamil Nadu are doing mostly RT-PCR alone; and they are doing a phenomenal number of tests. In Kerala, only half the labs in Kerala are doing RT-PCR and their capacity is low,” said Dr Arun, who has been closely monitoring Kerala’s testing strategies.  

“Besides, Kerala’s current positivity rate is increasing by the week. If Kerala tests more, they will get more and more positives in the coming days,” he noted. 

*Graph by Dr Arun NM

Dr Srinivas of Sree Chitra Thirunal Institute said that both ICMR and the state government are working to increase the testing capacity. “ICMR provides the RT-PCR RNA extraction kits while the state provides the PCR/RNA extraction kits and all the other consumables and necessary equipment and manpower.” 

However, he also agreed that more private and government testing centres are required to carry out more tests. “As Kerala has declared community transmission in some areas, a higher load of samples can be expected and an increased number of testing labs are required to shoulder this extra burden. More number of testing centres in a distributed manner at various parts of a district will ensure faster results,” he said.

*Graph by Dr Arun NM

Antigen testing in areas with community spread

Kerala has thus far primarily been focussing on identifying, testing and isolating/treating people coming from other countries and states and their immediate contacts. However, it had to expand its testing strategy when the officials suspected community transmission in early July, and thus adopted antigen testing. 

An antigen test will show if an individual is currently infected. Unlike an RT-PCR test, which detects the presence of the genetic material of the virus, an antigen test detects the spike proteins on SARS-CoV-2. 

“However, we are relying more on antigen testing at this point than RT-PCR. Antigen testing is the second-best option, as it is faster with a turnaround time of 15 to 30 minutes. However, since about 30% samples may generate false negatives, they will have to go for the RT-PCR test again, which will cause further delay in generating results of the existing samples,” he pointed out. 

 

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