Reliance on RAT in rural Maha indicates caseload may be higher

Shortly after receiving his first dose of the vaccine Ravindra Khaire, a pharmacist from the small town of Ramtek in Nagpur district, began to exhibit symptoms of the coronavirus disease: a persistent cough, low-grade fever and body ache

Shortly after receiving his first dose of the vaccine Ravindra Khaire, a pharmacist from the small town of Ramtek in Nagpur district, began to exhibit symptoms of the coronavirus disease: a persistent cough, low-grade fever and body ache. The 49-year-old went to a civic hospital for an RT-PCR test on April 20. The technician who collected his nasal and throat swabs told him that his report would reach him over a Whatsapp message in a few days. By April 28 however, Khaire’s symptoms had worsened and his oxygen saturation level fell below 90. He went to a private hospital where he was made to undergo a Rapid Antigen Test (RAT) which confirmed that he was Covid positive. His RT-PCR test result came the following day.

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RTPCR or Reverse Transcription Polymerase Chain Reaction is considered the most reliable laboratory test for detecting SARS-CoV-2. Experts say that an RT-PCR has a sensitivity of around 70%. An RAT, on the other hand, can be performed outside a laboratory. Its result shows up within 15 to 30 minutes. However, experts estimate its sensitivity to be around 50%, which means that a negative result isn’t necessarily correct. According to guidelines issued by the Indian Council of Medical Research (ICMR), a positive RAT should be considered as a confirmed result but if a person tests negative on a RAT, he or she should undergo RT-PCR for confirmation.

State health minister Rajesh Tope emphasised the use of RAT kits mainly in rural areas, where the laboratory capacities were inadequate or absent – as cases surged, laboratories that conducted RT-PCR tests were filled to capacity. Most districts began targeting containment areas, markets, and other crowded places for rapid tests, and health care workers also began to rely more on RAT kits in camps conducted in villages and primary health centres (PHCs), reserving RT-PCR kits for those who were symptomatic.

In Nagpur district for instance, of the total 50,904 tests conducted in February 2021, 60.6% were RAT. In April, of the total 240,815 tests conducted, 60.92% were RAT. The reliance on rapid tests however decreased in May, as 60.9% of the 142,030 tests conducted were RT-PCR.

Experts estimate that more than 40% of tests conducted in the state are with RAT kits. “Nearly 60% of these tests are RTPCR and the remaining 40% are RAT,” said state surveillance officer Dr Pradeep Awate. “Some districts may have a slightly different ratio, with more rapid tests. But we are following the ICMR guidelines which have now allowed upscaling of RATs wherever necessary,” he said.

Simply put, through March and April, as Maharashtra led the number of Covid-19 cases in the country, it’s like that the number of cases was higher as more RAT kits were being used.

Reliance on rapid tests

ICMR’s testing advisory issued on May 4 recommended the upscaling of RATs to meet the overwhelming demand for testing, but in April, the health secretary Rajesh Bhushan had upbraided Maharashtra for not following the appropriate ratio of RTPCR to RAT kits (70:30): Maharashtra’s overall weekly share of RT-PCR test was 57.6% in the week April 7-13, compared to 70.3% in the week February 17-23.

In Amravati district, officials issued orders to target vegetable vendors, milkmen, delivery persons, among others with RATs as a means to break the chain of the infection. The district’s lone government laboratory in the Sant Gadge Baba Amravati University has a capacity to carry out only 2,500 RT-PCR tests, which also explained the reliance of RAT kits. “At present, we are carrying out anywhere between 4000 to 5000 tests daily, of which nearly 60% are rapid tests,” said district health officer Dr Dilip Ranmale. The district has also been facing a shortage of the Viral Transport Medium (VTM) kits required for the collection, storage, and transport of samples. This has further pushed the dependency on rapid tests.

Amravati’s district surveillance officer Dr Revati Sable said that the statistics of RT-PCR and RAT is dynamic. “Our RT-PCR count goes up when we have more symptomatic people. We are doing more rapid tests in containment zones, gatherings, marketplaces, and in patients who have to undergo medical procedures,” she said.

In the Gadchiroli district which currently has over 1300 active cases, nearly 80% of the 1500 tests carried out daily are rapid tests. “The district’s only laboratory in the civil hospital had a capacity of carrying out only 500 RT PCR tests daily,” said district health officer Dr. Shashikant Shambharkar. “The capacity has been increased to 1000 just a few days ago,” he said.

Shortage and delay

Pune’s rural areas are currently facing a shortage of RAT kits.

Rajendra Tukaram Meher is the sarpanch of Warulwadi village -- home to more than 15,000 residents -- in Junnar taluka, Pune district. The nearest government hospital which collects swabs is 22 kilometres far away. “In the last week of May, an old lady died due to Covid-19 and we had requested her family members to get tested. But the health officials said that there were no rapid antigen kits available. In another case a boy had tested positive and his family members, about 6-7 of them who live in the same house also wanted to be tested, but there were no kits available. They had to pay about ₹500 to get a rapid antigen test done from a private laboratory that offered home collection. Earlier the gram panchayat used to conduct rapid antigen testing camps, but due to the shortage of kits, we stopped holding the camp a month ago,” Meher said.

Zilla Parishad Chief Executive Officer Ayush Prasad said that the shortage of RAT kits in the past month was due to a few reasons. “It is true that there is a shortage of rapid antigen testing kits. A batch which was supposed to come from Bangladesh failed quality control and was held back. Secondly, manufacturers hiked the price of kits from ₹57 per kit to ₹123 per kit. In Pune, the demand for RAT kits rose. During the months of January and February, our RT-PCR ratio had touched up to 90% and so to bring it down to 70%, we increased RAT testing, since we are required to maintain a 70-30 ratio. RAT provides instant results which helps in early isolation. In the beginning of May, we had distributed 100,000 RAT kits which were used up in two weeks.”

Dr Deepak Selokar, district health officer, Nagpur, admitted to delays in RT-PCR reports until April this year as every public health centre and civic hospital in the district sent swabs for testing to two government-run medical colleges ( Government Medical College and Hospital in south Nagpur and Indira Gandhi Government Medical College and Hospital in Central Nagpur) and AIIMS, Nagpur. “Given the enormity of testing samples from Nagpur city as well as rural Nagpur, sometimes we get the reports late,” he said.

Seolkar said that the RT-PCR sequencing machines were increased from two to five; five more are expected at the government run medical college and hospital in Nagpur. Starting May, an average of 600-700 RAT and RT-PCR tests from 53 Public Health Centres, 10 rural hospitals and two sub-district hospitals from Nagpur rural are sent to these three Nagpur-based facilities every day for investigation. He said that local healthcare workers now advise home quarantine to those coming for RT-PCR test till the results come for avoiding further spread of the virus in case they test positive.

Dr Chetan Naikwar, the chief of the Ramtek civic hospital that Khaire visited on April 20, said that mobile vans equipped with RAT kits go out to villages every day and carry out at least 30-50 tests. One mobile van consists of three-member team, who is given a training to collect swabs and use the test kits. “I personally coordinate the entire testing operation and ensure that villagers get the report instantly,” Naikwar said. Apart from this, ASHA workers visit homes every day to assess the situation on the ground and identify symptomatic patients if any. However, work is impeded because many posts of technical staff like lab technicians lie vacant.

Breaking the chain of transmission

If delay in receiving test results is one side of the coin, the other is that private labs are not getting enough clients in rural areas. Dr Dhawal Tiwari of Swami Yogiraj Hospital at Ramtek said that they hardly get one or two patients every day who approach them for testing as many villagers prefer government hospital for free testing.

“We have no facility for RT-PCR test here and therefore we make do only with RAT,” said Tiwari. Each kit costs ₹600. “We hardly get any patients from neighbouring villages as mobile vans now go to almost all villages for such test,” he added.

“The endpoint of testing is to break the chain of infection and immediately isolate people who have the infection,” said Dr. Abhay Chowdhary, head, department of microbiology, DY Patil University, Navi Mumbai. “RT PCR is definitely more reliable, but one should roll out whichever tests are available easily so that a large number of people can be tested,” said Chowdhary, former head of Haffkine Institute.

This certainly held true for Khaire, who during the delay in receiving his results, went about his daily life. “I went shopping to buy vegetables and met people as usual without knowing that I was infected,” he said. “I repeatedly contacted the government hospital staff for the report. They kept telling me I would receive it soon over WhatsApp,” he said.

Health officials said that there is a severe resistance against testing in the rural pockets. “People come down to abusing healthcare workers and even fists and blows at times,” said Shambharkar, Gadchiroli’s district health officer, adding that misleading messages forwarded on WhatsApp have become a problem. “The reluctance is widespread in the rural areas. They fear that if they test positive, they will be sent to a hospital. One WhatsApp forward spread a misleading message that people’s kidneys are being harvested illegally at the hospitals. We are trying our best to spread awareness and have asked the healthcare workers to bust such wrong information,” he said.

Thus far, Maharashtra has carried out over 34 million tests; its current testing figure is 303,056 tests per million population. By comparison, Kerala’s average is 562,702 tests per million and Tamil Nadu’s is 402,623 tests per million population. “Kerala’s model of testing and early detection is a good one,” said Soumitra Ghosh, associate professor at the Centre for Health Policy, Planning and Management, Tata Institute of Social Sciences. “A dense state like Maharashtra should therefore be conducting many more tests per day. The thrust should definitely be on the RTPCR tests as the error margin is low.”