6.5 C
New York
Friday, July 30, 2021

How saliva can predict COVID-19 better – study

Must Read

A systematic review of 37 research found that salivary samples can replace swabs to diagnose coronavirus, with better accuracy and lower price

Recent studies from Yale University have detected how saliva is to prevent complications in those infected with covid-19, through the viral load in patients’ mouth that could even help to personalize the treatments and leave the swab test behind.

After a year of combat, the scientific community is learning to anticipate the movements of the virus. One of the latest advances has been studied by immunologist Akiko Iwasaki, at Yale University in the United States. Their preliminary results suggest that the amount of virus in saliva serves to predict the outcome of the disease.

“The viral load on saliva in the first few moments is correlated with the severity of the disease and mortality,” says the Iwasaki team, which has thoroughly analyzed 154 patients infected with covid-19 at the university hospital in New Haven City.

The results of the study show that the levels of the virus increase progressively from a minimum in mild patients to a maximum in seriously ill patients and in people who have died from the coronavirus.

The higher viral load on saliva is associated with known risk factors, such as advanced age, male sex, cancer, heart failure, hypertension, and chronic lung disease.

“If we take saliva samples and analyze the viral load—especially at the beginning of the infection, when the person arrives at the hospital—could greatly help doctors predict the patient’s prognosis and choose treatments,” says microbiologist Arnau Casanovas, who after seven years at Yale University and now hired in August by American biotechnology Tangen Biosciences, dedicated to designing new diagnostic methods, has participated in the new study, which is still a draft that requires a final pending revision for publication in a specialized journal.

The team led by Iwasaki argues that saliva helps predict disease progression much better than samples taken by the already popular nasal swab.

One of their hypothesis is that the swab test in the nose only reflects the multiplication of the virus in the upper respiratory tract, while saliva also shows the situation in the lungs. The mucociliary system — a defense mechanism for expelling germs — would carry the coronaviruses from the lower respiratory tract to the mouth.

The research shows that the higher viral load in saliva is also associated with a higher amount of biomarkers in the blood of the inflammatory reaction characteristic of severe COVID-19 cases. The higher viral load, by contrast, is linked to lower levels of platelets, white blood cells, and specific antibodies against the coronavirus.

Elisabet Pujadas, a pathologist and researcher at the Icahn School of Medicine at Mount Sinai Hospital in New York, applauds the new study. “It brings a valuable perspective: that saliva may have a greater value than previously thought for diagnosis and prognosis.” 

His team had already published in August the relationship between the highest viral load analyzed in nasal samples and mortality from covid-19. 

“It is possible that saliva can better reflect lower respiratory tract infection,” said Pujadas at that time.

Since the study so far only includes 154 patients, Pujadas believes that it may be premature to conclude that saliva should already be used instead of swabs. “However, these promising results justify more resources in collecting and studying saliva samples.”

For the pathologist, the main lesson is that it would no longer be necessary to classify only covid-19 patients with a simple positive or negative. Additionally, your viral load must be measured. 

“For certain viruses, such as HIV, the quality standard is viral load, because years of research have shown that it has important implications for patient risk and affects our treatment strategy. So it should also be with the covid,” he said.

A systematic review of 37 investigations has just shown that saliva samples can replace swabs to diagnose COVID-19, with the same precision and lower price.

“We have been saying for quite some time that it would be better to use saliva as a priority sample. It’s much easier to pick up saliva than a nasopharyngeal swab. You don’t need nurses. Each person can spit at home in a small box. And you avoid the risk by taking the sample with the swab, because sometimes people get sneezing or coughing and aerosols are generated,” Casanovas argued

- Advertisement -
- Advertisement -

Latest News

These people have eight times higher risk of Covid infection and death – says study

A recent study published in the journal Scientific Reports examined 1.3 million patients and discovered that those advised to...
- Advertisement -

More Articles Like This

- Advertisement -