There are no reliable studies to definitively prove a direct correlation between disease severity / infectiousness and Ct values, therefore it is not recommended to rely on numerical Ct values for determining infectiousness of COVID-19 patients and deciding patient management protocols.
Interpretation guidance:-
Testing of referred clinical specimens was considered on the basis of request / referral received from /
through State Surveillance Officer (SSO) of concerned State Integrated Disease Surveillance
Programme (IDSP)/ any other health care facility affirming requirements of the case definition/s
A single negative test result, particularly if this is from an upper respiratory tract specimen, does not
exclude infection*
A positive test result is only tentative, and will be reconfirmed by retesting
Repeat sampling and testing of lower respiratory specimen is strongly recommended in severe or
progressive disease. The repeat specimens may be considered after a gap of 2 - 4 days after the
collection of the first specimen for additional testing if required. *
A positive alternate pathogen does not necessarily rule out either, as little is yet known about the role
of coinfections
Please note that these results are not to be used for any thesis or presentations or for Publication in
any Journal without the prior permission of the Director General, ICMR
