Chennai Dental Research Foundation (CDRF), recognized by the Department of Bio-Technology (DBT), Government of India, Voluntary Health Services (VHS) Hospital, Chennai, and Ragas Dental College & Hospital presented a revolutionary concept “Saliva Rapid COVID Test” at Voluntary Health Service (VHS) Hospital.
They have conducted unique saliva-based research for rapid COVID diagnosis after getting Institutional Ethics Committee (IEC) clearance of VHS. This is an easier and less expensive test. This antigen test is a well-recognized technique worldwide and FDA approved in the USA. The study has been accepted for publication in a leading research journal (Oral Diseases) for the first time from India.
The use of mouth rinses to reduce the risk of transmission of COVID disease through saliva when patients attend dental clinics is already being practiced worldwide and also in India. Various mouthwashes were also studied.
The press meet was addressed by:
- Dr. Yuvraj Gupta / Director & COO, VHS
- Dr. Gunaseelan Rajan / President / CDRF
- Dr. N. Kumarasamy / Director, VHS-IDMC, VHS
- Prof. K. Ranganathan, Ragas Dental College and Research Director, CDRF
- Dr. K. Priya / Scientist & Head / Department of Clinical Research / VHS
The gold standard for the COVID test is RT-PCR using Naso-Pharyngeal (NP) and Oro-Pharyngeal (OP) swabs. However, saliva-based tests have been approved in the USA for the following reasons:
- Simpler to use since it can be done without any need for technician and use of PPEs;
- Much faster (report ready in minutes compared to many hours for RT-PCR);
- Much cheaper.
This test is called the Rapid Antigen Test (RAT). ICMR has recognized RAT test using NP & OP samples but not for Saliva.
CDRF and VHS have conducted a study using Saliva for the RAT test and found very good results. These results are better than the minimum standards set by ICMR – Sensitivity of 56% (50% minimum by ICMR) and Specificity of 100% (95% minimum set by ICMR) These research results have been accepted in the international journal “Oral Diseases” in Feb 2021.
If this is approved by ICMR & the Government of India, it will make it a very rapid, simple, safe, and economical test for COVID. This will be very effective for screening programmes, community testing, and wherever quick results are needed. This can also be very useful in Out-Patient Department, especially in dental practices.
Furthermore, the use of Povidone-iodine, hydrogen peroxide, and chlorhexidine mouthwashes have been shown to reduce the burden of the virus in saliva and respiratory droplets collected from a face mask. This is the first-time virus particles isolation has been shown from respiratory droplets.
The use of mouthwash especially before dental treatment makes it safer for the dentists and the staff working closely with patients during dental treatment. These findings have been submitted to the journal viz., “JAMA” and can be seen in “Med Archives”.
With COVID cases increasing again in India, saliva-based rapid tests (RAT) which are easier to do and more economical will be a very useful method to help control the spread of COVID. A positive saliva test is confirmatory but a negative test should still be followed up by an RT-PCR test.