Paucity of staff slows Gurugram’s primary Covid testing strategyUpdated: Jun 27, 2020, 23:58 IST
Gurugram: With only 41 trained technicians available to carry out sampling and testing for the coronavirus (Covid-19) disease, targeted collection of throat and nose swabs (for RT-PCR testing) has slowed down in Gurugram. Antigen and rapid antibody tests are now being conducted along with tests as per the district’s primary strategy, and the health department’s resources are spread thin, officials said.
Data from the department shows private labs are now collecting most of the samples in the district (for confirmatory RT-PCR tests), while number of samples collected by the health department (also for RT-PCR, as part of targeted surveillance) have not significantly increased in June, despite a surge in positive cases.
Chief medical officer Dr Virender Yadav, said: “Earlier, all technicians were engaged in collecting and testing swabs using RT-PCR method. Now many of them are also doing rapid antibody tests and antigen tests, which increases the workload.”
Another official, requesting anonymity, revealed that there have been multiple instances when lab technicians have tested positive for Covid-19. “The technician has to isolate and seek medical help, and then return when they test negative after two weeks. When this happens, it slows down sample collection,” the official said.
Collecting samples from the field, officials explained, can be a laborious process involving not just taking swab but also proper storage and transportation, and data management. “Earlier, all 41 of the health department’s technicians were engaged in collecting and testing swabs using RT-PCR method. Now many of them are also doing rapid antibody tests and antigen tests, which increases the workload. For sampling, there are 10 teams of two technicians each for RT PCR and antigen tests. The target is about 100 samples per day, per team.”
However, data shows that between June 1 and June 12, the department collected only 247 samples per day (through targeted surveillance), which increased to 283 samples per day between June 16 and June 24 (an increase of about 14%). Over the past three days, with the introduction of antigen tests, this number has grown to about 350 samples per day -- less than half the target.
“The increase in sample collection is not very significant when you consider that during the same period, the number of cases in Gurugram rose by almost 400%, from 903 in early June to over 4,500 by June 24. Deaths have also soared, from just three on June 1 to over 50 on June 24,” said Dheeraj Singh, a city-based data scientist who has been tracking the health department’s data.
Yadav, however, responded saying the health department would soon be able to collect at least 1,500 samples daily. “We will have staff of 61 technicians soon, of which 20 new recruits will conduct antigen tests, while the remaining will collect and test samples for RT-PCR. Our aim is to collect at least 1,500 samples per day by mid-July,” he said.
CONTACT TRACING ALSO AFFECTED
Experts said this trend also calls into question the efficiency of contact tracing in Gurugram. “A surge in cases, as Gurugram witnessed earlier this month, implies that many more primary contacts need to be traced and tested. Accordingly, the health department should be collecting that many more samples from people with a high ‘pre-test probability’ of being positive, which are people who have had prior contact with confirmed cases,” said Dr Prabhakaran Dorairaj, vice president (research and policy) at the Public Health Foundation of India.
Thus, if the number of tests conducted through targeted surveillance isn’t increasing by a sizable margin, “It is likely that susceptible individuals aren’t being actively sought out through contact tracing. This could also be why the mortality rate in the district is going up,” Dorairaj said.
Lapses in the district’s implementation of the ‘test, trace, isolate’ strategy was brought into focus earlier this week after Haryana’s additional chief secretary, Vijai Vardhan, conducted an audit of contract tracing data. A district level official with Haryana’s Integrated Disease Surveillance Programme, seeking anonymity, said, “The audit found that in four days in June, 587 cases were detected but contact tracing for over 250 was not carried out.”
An ASHA worker, who requested not to be named, detailed the logistical challenges of contact tracing. “We are asked to cover at least 15 families in a day. Since the numbers are increasing every day, it is not easy to cover all households. We have been doing this all summer, but on some days the heat was so bad that it wasn’t possible to trace all contacts of every person,” the worker said.
TARGETED SURVEILLANCE NECESSARY
Dr Ram Prakash, district epidemiologist, clarified that targeted testing, tracing and isolation are still Gurugram’s best option to curtail further transmission of Covid-19. “We are still focused on contact tracing. Despite issues, the number of samples collected through targeted surveillance has been increasing, even if only gradually. It is not a cause for concern because we are still doing adequate RT-PCR tests, which is the most reliable diagnostic tool, with the help of private laboratories.”
HT had reported on June 23 of an increase in the number of private labs conducting tests in Gurugram. Between June 16 and June 24, for example, private labs collected 61% of all samples from the district (as opposed to 41% in the preceding fortnight).
Experts have cautioned against relying on private testing to make up for the slowdown. “Targeted surveillance is the best way to catch ‘super-spreaders’ who may be transmitting the infection to a sizable number of people. It is also the best way to find infected individuals before their symptoms worsen. Private testing, on the other hand, is arbitrary. It cannot be used as a substitute for contact tracing,” Dorairaj said.
He and other experts also said that antigen tests, which have a low sensitivity (and yield a greater percentage of false results) rate, were not a viable replacement for RT-PCR.
The CMO, however, clarified that both antigen and sero surveillance in the district were being carried out in a targeted manner in hotspot areas. “Targeted sampling is being conducted through sero surveillance and antigen detection tests. Through these tests we are focusing on specific groups of population who are susceptible to contracting the virus,” Yadav said.
With the district health department now pooling testing data from private and government labs and even antigen tests in its daily bulletin, experts say Gurugram’s true performance in the fight against Covid-19 is being obfuscated.
“When you test randomly, like private labs are doing, you will get a lower positivity rate. But lower positivity through targeted testing is the ideal way, not by adding random samples to your testing pool,” said Rajesh Kumar, an epidemiologist and former professor of community medicine at PGIMER Chandigarh.
In light of this, experts also called for a revision of the district bulletin’s format. “The data for private testing, targeted surveillance and antigen testing must be presented separately. When you club data from three separate testing strategies, we are unable to see the real picture,” said Singh, drawing attention to Gurugram’s declining test-positivity rate.
“To get a correct picture of the positivity-rate, we need de-segregated numbers to show how many samples are being collected and tested via targeted RT-PCR tests,” Singh added.
(with inputs from Archana Mishra)