Sanjeev Kumar Patro

News Highlights

  • When RTPCR TaqPath Is needed, RAT (Rapid Antigen Tests) constitute nearly 60 percent of Covid-19 tests in Odisha.
  • At the same time, almost all the RTPCR tests conducted in the State are probes based on the TaqMan method.

The threat of the Omicron Covid-19 variant triggering the Third wave in Odisha looks very high. Many trigger factors are galore in the State.

While the State is figuring among the top-15 states where the beneficiaries due for second vaccine dose remain very high, the RT-PCR test used in Odisha is fluorescent probe-based TaqMan method, not the TaqPath, the one asked by WHO to detect the Omicron infected individuals.

As per the latest data available with the Union Health Ministry, despite completing the wait-in period, a whopping over 37.97 lakh beneficiaries are yet to take the second dose. For which, the State finished 15th, among 37 states and UTs.

Moreover, the RAT (Rapid Antigen Tests) constitute nearly 60 percent of Covid-19 tests in Odisha. At the same time, almost all the RTPCR tests conducted in the State are probes based on the TaqMan method.

The above lot of factors make Odisha vulnerable to the Third Wave, just as the RAT-led testing policy had fanned the second wave triggered by the Delta variant.

A change in testing strategy seems the need of the hour when the Omicron Covid-19 variant has been identified in three states - Karnataka, Gujarat and Maharashtra - in quick succession. Significantly, migrant workers from Odisha work in large numbers in the three job-intensive states in the country.

How Testing Method Makes The Difference?

In order to curb the brisk Delta variant transmission during the second wave, the Union Health Ministry had asked Odisha and other states to ensure 70 percent RTPCR tests.

The rationale behind the Centre's directive is the RAT (Rapid Antigen Test) targets the nucleocapsid protein or N-protein of the virus and this test can only assess for the acute infection, not the prior infection.

As Odisha relied heavily on RAT, the patients identified were at acute state, which not only led to higher mortality but also ensured the rapid transmission of the Delta variant virus. The result was Covid-19 positives touched new heights in the Second Wave in Odisha.

What Link Delta Has With Omicron?

Post declaring Omicron a global risk, WHO has observed that for rapid and efficient detection of highly transmissible variants in circulation, governments need not wait for genome sequencing. Rather, authorities go for the ThermoFisher TaqPath RTPCR tests to detect and isolate large cases in a short span of time, thereby, preventing the Covid-19 explosion due to faster transmission variants.

Even though the RTPCR tests based on the TaqMan method can detect a Covid-19 positive, it is unlikely to hint at a wider spread of new variants.

As per WHO, the TaqPath Covid-19 tests showed the SGTF (S Gene Target Failure) indicating the presence of the Omicron variant.

"Since Omicron has gone through as many as 32 mutations in the S-gene, the RT-PCR TaqPath test resulted in S-gene negatives or say S-gene dropouts (means the test failed to detect the S-gene of the Covid-19 because the virus had gone through mutation and hence evaded the test). This non-detection has alerted the health authorities about the possible spread of Omicron in the community leading to efficient detection of Omicron cases without genome sequencing," observed WHO.

As per the Union Health Ministry report, states over-reliance on RAT had made the second wave bigger in the country.

The twist this time is the ThermoFisher TaqPath RTPCR tests look timely to pre-empt the Omicron strike on the State and the country.

The Tamil Nadu govt has brought in a mandatory protocol recently that asks for screening of all international travellers with ILI (Influenza-like Illness) symptoms via the ThermoFisher TaqPath RTPCR tests.

Is Vaccine Hesitancy A Trigger Factor?    

As per a recent study published in MedRxiV, the spread of the Omicron variant has been associated with a decrease in the hazard of primary infection and an increase in re-infection hazard.

Like the Delta variant, the Omicron has the necessary mutations to evade natural immunity, at the same time experts worldwide suspected that owing to a large number of mutations in S-protein, it may render the new variant evade the vaccine-developed immunity.

In the given backdrop, the high order of vaccine hesitancy may make the State vulnerable to South African variant attack.

Fluid Covid-19 Scenario In Odisha?

The letter of Union Health Secretary Rajesh Bhushan to Odisha underlined the fault lines in State's fight against the Covid-19.

Talking on Khordha district, which has achieved a higher vaccination rate (60%) in the State, Bhushan pointed out that the district has reported a high quantum of weekly new cases with 900 new cases reported in the week ending December 3.

The ground data shows that the high order of cases in the district is, infact, a larger degree of re-infections. Moreover, the alarm bell for the State is, as per a WHO report, large breakthrough infections may roll out the red carpet for the lethal variants.

The letter has also highlighted that six out of 30 districts - Dhenkanal, Kandhamal, Nabarangpur, Kendujhar, Anugul and Balangir- have reported a rise in the weekly caseload vis-a-vis the week ending November 26,

Moreover, in the letter, the Union Health Secretary has also mentioned that Odisha has reported 7,445 new cases during the same period,  and contributed 2.5 per cent to India's new cases vis-a-vis the past month.