PESHAWAR: The Khyber Pakhtunkhwa government has approved a new policy for Covid-19 testing to ensure rapid diagnosis of patients in those districts where transportation of samples for PCR to the laboratories has been a daunting challenge since the onset of the pandemic.

The antigen detection rapid test (Ag-RDT), already approved by World Health Organisation and federal government, will be introduced in eight districts including Chitral Upper and Lower, Torghar, South and North Waziristan, Kohistan Upper and Lower and Kolai Palas in the first phase.

Under the new strategy, the hospitals will use Ag-RDT method, which ensures results within 30 minutes as compared to polymerase chain reaction (PCR) that takes 24 hours. The policy, to be adopted immediately, was in accordance with the National Policy, said a notification by health department.

Formerly, KP government mainly focused on PCR testing, however, with the increasing acceptance of Ag-RDT in the global response against coronavirus, the government has decided to incorporate it into the testing policy.

Antigen detection test will be introduced in eight districts

The notification said that Ag-RDT was a point of care (PoC) test and in any infectious diseases, a test with rapid turnover time and ease of use added to early diagnosis, management and control of the ailment.

It has a rapid turnaround time, which is critical for the identification of Covid-19 infection and rapid implementation of infection prevention and control strategies. These tests can augment other testing strategies, especially in settings where RT-PCR testing capacity is limited or testing results are delayed due to long sample transportation and laboratory turnaround times.

The sensitivity of Ag-RDT is highly dependent on the viral load of the virus and the performance is the highest when the sample is collected two days before the onset of symptoms (pre-symptomatic) and five days after the onset of symptoms (symptomatic).

A negative Ag-RDT does not exclude Covid-19 infection in a clinical setting up to 20-40 per cent of the time and should be reconfirmed by PCR in case there is no alternate diagnosis or when the patient is suspected clinically.

All the healthcare facilities, especially the ones where the turnover of patients is high and quick decisions are required, will be provided with the Ag-RDT kits and all those patients, who are presenting symptoms compatible with Covid-19, influenza like illness (ILI) or severe acute respiratory illness (SARI), will be tested by Ag-RDT initially.

If the test is positive in appropriate setting (pre-test probability is high), it will be considered positive and no confirmation will be required. Contrary to this, if a test is reported negative in a patient with high pre-test probability (high risk group), the test will be re confirmed by PCR in all symptomatic and 20 per cent of the asymptomatic contacts.

A subclass will be all the emergency surgeries where the time is crucial and delays in surgeries can’t be afforded but it will not be used for any elective procedures and surgeries. It will be used in close congregate settings as an outbreak response for quick segregation where PCR confirmed cases are already reported. In such scenarios, the test can be repeated one week apart in order to not miss any person, who can be infective.

These settings include healthcare facilities, teaching institutions, prisons, camps, factories and any other place where the movement is otherwise controlled.

At Pakistan Afghanistan border where the turnover is very high and those, who are symptomatic on screening and need quick testing on site for quick segregation, should be tested by Ag-RDT and 20 per cent of the negatives of these symptomatic should be confirmed by PCR and these persons should be instructed to strictly follow the isolation recommendations or should be quarantined if desired.

Published in Dawn, December 3rd, 2020