Serum testing – hope for early detection of disease

With more than half a million vials of plasma, Dr. Michael Mina conducted serum tests in the hope of finding the way nCoV spread into the United States.

Last summer, 500,000 vials of plasma from blood samples from people across the United States were sent to the lab of Dr. Michael Mina, an epidemiologist at Harvard TH Chan School of Public Health. Blood samples were collected by Octopharma plasma donation company in early January 2020, when Covid-19 had not yet had a strong outbreak.

Mina et al. Used plasma samples for the Global Immunological Observatory pilot project. By using serological tests, the team hopes to find a way that nCoV spreads into the United States weekly. The second goal is to create giant surveillance systems capable of examining blood samples around the world, thereby detecting the presence of antibodies to hundreds of viruses in a short time. When the next pandemic sweeps over humanity, scientists have in hand detailed information and updates on the number of people who have ever been infected with the virus, and the body’s reactions.

Serology tests can help scientists get an overview of which viruses a person has since childhood. Viruses that have never caused symptoms in the body are still detected.

“The body is like a small data storage machine that keeps track of viruses that have entered the body unconsciously,” Mina said.

Serology tests give results that are not possible with conventional diagnostic tests, according to Derek Cummings, an epidemiologist at the University of Florida. With this large database and detailed clinical information, researchers can tell the difference between the immune response of asymptomatic people and patients. Serological tests can also predict the level and time to reach a community’s immunity before the virus spreads, causing an outbreak.

“We all want to know what happens in a community, and how they prepare for a pathogen in the future,” Cummings said.

Dr. Michael Mina, epidemiologist at Harvard TH School of Public Health Photo: NY Times

The method can also detect commonly overlooked viral developments. In 2015, a team of doctors discovered Zika epidemic after noticing a group of infants with abnormally small heads, who were born 7-9 months after the mother became infected. “If we had data from a serological test, we would have been able to detect the pathogen before an outbreak,” he explains.

Serological surveys are often small and difficult to organize due to the need to take blood samples from volunteers. For the past few years, Mina’s team has been discussing setting up a large automated surveillance system, using samples left over from routine laboratory tests.

“If we set up the system from 2019, when nCoV appeared in the US, we had data on hand showing how the virus was spreading in New York and other states without any other methods.” Mina shares.

He said even though the “immune observer” failed to detect nCoV, it still revealed an abnormally high number of corona virus infections that had interacted with the patient’s immune system in an unexpected way. These could be the signals for health professionals to begin genetically sequencing patient samples, find the “culprits”, and create a facility to shut down New York City earlier.

Setting up an “immune observatory” could be financially daunting, amounting to an estimated $ 100 million. There is also a need for consensus between hospitals, blood banks and other blood supplies, and patient and donor consent.

However, Jessica Metcalf, an epidemiologist at Princeton, a member of the research team, stressed that this is a worthwhile project. A few years ago, in a small survey, she and her colleagues found that Madagascar’s immunity to measles was worryingly low. A measles outbreak here in 2018 claimed the lives of more than 10,000 children.

With the huge amount of plasma samples in the storage cabinets, Dr. Mina is starting to do serum tests, focusing on nCoV. Pending the establishment of the automated test facility and the sample processing, the team spent time testing the first batch of plasma.

“Our big idea is that the world no longer has to spend so much money on this work. We should have regular plasma tests done,” Mina said.

Le Hang (Follow NY Times)


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