Most Read Articles
Jairia Dela Cruz, 22 Apr 2020
A wristwatch-like device that monitors pulse, breathing and blood oxygen levels of the user allows physicians to provide care remotely both in hospital and nontraditional settings, and may help in the fight against the coronavirus disease 2019 (COVID-19) pandemic.
Roshini Claire Anthony, 27 May 2020

The use of a vaginal cleansing intervention prior to Caesarean delivery reduced the incidence of surgical site infections (SSIs), according to a study presented at ACOG 2020. However, the addition of intravenous (IV) azithromycin prophylaxis had no added impact on SSI rates. 

Pank Jit Sin, 21 May 2020

Persons suffering from asthma should pay particular attention to SARS-CoV-2 precautionary measures such as social distancing, regular handwashing, and wearing of masks on top of keeping their asthma in control. This is because data collected so far paints a bleaker picture for asthmatics than the normal population should they catch COVID-19.

Natalia Reoutova, 2 days ago

A comprehensive review of neurological disorders reported during the current coronavirus disease 2019 (COVID-19) pandemic demonstrates that infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affects the central nervous system (CNS), the peripheral nervous system (PNS) and muscles, leading the Environmental Neurology Specialty Group of the World Federation of Neurology to propose implementation of international neurological registries.

Saliva holds promise for COVID-19 testing

Tristan Manalac
23 Apr 2020

SARS-CoV-2 appears to be detectable in saliva samples, which may open up options in terms of rapid testing, according to a new study.

“Saliva is a reliable biological fluid that could be a candidate for a diagnostic rapid test, because it can be easily performed also by no-healthcare professionals in a screening programme,” the researchers said. “Therefore, it is fundamental that the salivary load in asymptomatic carriers be analysed to establish a sensitivity threshold for a future test.”

Twenty-five patients (mean age, 61.5±11.2 years; 17 males) with severe or very severe coronavirus disease 2019 (COVID-19) were enrolled. Most of them also had cardiovascular or dysmetabolic disorders, including hypertension, obesity and dyslipidaemia. Around 20 percent had previous conditions of the lungs, upper airways or mediastinum. [J Infect 2020;doi:10.1016/j.jinf.2020.04.005]

Salivary samples from all 25 participants tested positive for SARS-CoV-2 on real-time reverse transcription-polymerase chain (rRT-PCR) reaction. Cycle threshold (Ct) values ranged from 18.12–32.23, with an average of 27.16±3.07. None of the samples had a Ct value exceeding 33.

Repeat swabs were collected from eight patients and all returned similar results, with no meaningful deviations in Ct values.

Ct values were not significantly influenced by the patient’s age (p=0.34), sex (p=0.31) or by the time elapsed since the onset of symptoms (p=0.25).

On the other hand, the researchers found that lactate dehydrogenase levels were significantly but inversely correlated with Ct (β, –0.02±0.008; p=0.04), suggesting that the viral load in the saliva samples was linked to the tissue damage as assessed by the biomarkers. In contrast, concentrations of the ultrasensitive reactive C protein were positively correlated, but only slightly significant (β, 0.01±0.005; p=0.07).

“In our research, we collected salivary samples from 25 patients affected by severe COVID-19 admitted at our hospital. Saliva was collected through the drooling technique or with a pipette, depending on the patient’s clinical condition; thus, sputum and oropharyngeal secretions were excluded from the collection,” the researchers said. Findings were generally harmonious with the diagnoses.

“These results reinforce the hypothesis that saliva is a reliable tool to be used in qualitative COVID-19 diagnosis through the rRT-PCR procedure,” they added.

Of note, two patients had discordant results, where salivary samples continued to test positive on the days that pharyngeal or bronchoalveolar swabs returned negative. One patient had this discrepancy confirmed 2 days after, while the other had two consecutive saliva samples that tested positive at the same time that three consecutive respiratory swabs were testing negative.

This raises “the concern about how to manage recovering patients at the moment of hospital discharge, because some of them could be contagious through their saliva even after two consecutive pharyngeal swabs that converted to negative, a serious danger for their own family and a troublesome issue for the social community,” the researchers said.

Future studies should also strive to understand why the virus is present in the oral cavity, they added. “It may appear in the mouth because it migrates from the nasopharynx or the lower respiratory tract to the oral cavity, but it can’t be excluded that a role may be played by the secretory activity of the salivary glands.”

Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Infectious Diseases - Malaysia digital copy today!
Sign In To Download
Editor's Recommendations
Most Read Articles
Jairia Dela Cruz, 22 Apr 2020
A wristwatch-like device that monitors pulse, breathing and blood oxygen levels of the user allows physicians to provide care remotely both in hospital and nontraditional settings, and may help in the fight against the coronavirus disease 2019 (COVID-19) pandemic.
Roshini Claire Anthony, 27 May 2020

The use of a vaginal cleansing intervention prior to Caesarean delivery reduced the incidence of surgical site infections (SSIs), according to a study presented at ACOG 2020. However, the addition of intravenous (IV) azithromycin prophylaxis had no added impact on SSI rates. 

Pank Jit Sin, 21 May 2020

Persons suffering from asthma should pay particular attention to SARS-CoV-2 precautionary measures such as social distancing, regular handwashing, and wearing of masks on top of keeping their asthma in control. This is because data collected so far paints a bleaker picture for asthmatics than the normal population should they catch COVID-19.

Natalia Reoutova, 2 days ago

A comprehensive review of neurological disorders reported during the current coronavirus disease 2019 (COVID-19) pandemic demonstrates that infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affects the central nervous system (CNS), the peripheral nervous system (PNS) and muscles, leading the Environmental Neurology Specialty Group of the World Federation of Neurology to propose implementation of international neurological registries.