Experts who spent the past year predicting the transmission of Covid-19 in the United States are now considering scenarios for the spread of new, more infectious strains of the coronavirus.
At the same time, the United States remains behind in monitoring coronavirus variants, despite having one of the most developed genomic sequencing infrastructure in the world.
The warnings come at a time when the United States appears to have peaked a devastating wave of winter infections, which at one time recorded more than 300,000 new infections and 4,000 deaths a day. Even though daily infections have dropped by more than half from the peak, with expected death rates also dropping soon, the threat of the most infectious variants now has some considering the possibility of a new outbreak.
“It’s a bleak projection, unfortunately,” said Ali Mokdad, a professor at the Institute of Metrics and Health Assessment (IHME) at the University of Washington, one of Covid-19’s leading academic analysts. “I am concerned about a peak due to the new variant and the relaxation of social detachment,” he said. “People are tired. People are very tired. “
Meteorologists still do not consider this the most likely scenario, although it is also not the worst scenario, but the addition of the model is a recognition of how dangerous new variants can be, even in an environment where hospitalization and mortality rates are expected to decline.
The IHME’s “fast spread variant” model predicts that total deaths may increase by 26,000 compared to the most likely scenario in May. This prediction would result in a total of more than 620,000 Covid-19 deaths at that time.
Notably, the most accurate are often “set” predictions, which bring many individual projections. The set forecast published by the CDC makes a forecast only until February 27, when it estimates that up to 534,000 deaths may occur. The IHME also estimates that universal masking can save 31,000 lives.
The most well-known variant of concern is the B117 strain, first detected in the United Kingdom. B117 is believed to be up to 50% more transmissible and is now circulating in the United States, where 541 cases have been found in 33 states, according to the Centers for Disease Control and Prevention (CDC).
Studies are still being carried out on how B117 can impact the effectiveness of the two vaccines currently authorized in the US, from Moderna and Pfizer. Another variant from South Africa, called B1351 and recently found in South Carolina, appears to reduce the vaccine’s effectiveness. New strains may also affect the effectiveness of some of the only treatments for patients with Covid-19, including monoclonal antibodies.
“If the new variant makes vaccines less effective and new variants appear, we could have an outbreak in the summer,” said Mokdad.
Variations in how a virus replicates genetic materials are expected and a characteristic of how viruses evolve over time. This may be especially true for viruses such as the coronavirus, whose genetic material is made of ribonucleic acid (RNA), because these viruses lack some “review” mechanisms that reduce mutations. Most changes are benign – like a typo on paper – and do not change the functionality of the virus.
But widespread and widespread global transmission has given the coronavirus millions and millions of chances to replicate and change as it changes. Random and inconsequential typos include rare changes that alter the behavior of the virus.
For example, B117 is believed to be more infectious. A more infectious virus is a more successful virus, and through thousands of new infections, natural selection will favor the successful virus, eventually replacing the previously dominant strains.
“A small percentage of a large number is still a large number,” said Emily Bruce, a virologist and researcher at the Center for Immunology and Infectious Diseases at the University of Vermont’s Larner School of Medicine. The variations are “a function of the number of people and the number of infections and replication cycles that the virus is going through”.
Scientists can detect these changes using state-of-the-art sequencing technology. This technology was used in the spring of 2020 to show that the origin of most Covid-19 cases in New York was actually from Europe, not China, as the Trump administration insisted.
While some laboratories were looking for specific projects using this technology, a national systematic surveillance program was never implemented. It was only in November that the CDC began receiving samples of Covid-19 patients from state laboratories on a regular basis. He now processes about 750 samples a week. The USA currently ranks 43rd in the world in Covid-19 genomic sequencing, despite having a well-developed genomic sequencing infrastructure.
“There are people who have done spectacular work here, but it has not been nationally funded and strategized the way leaders in the field have done it,” said Bruce.
The cost of genomic sequencing has plummeted since the beginning of 2000, when ambitions to map the human genome cost $ 100 million, according to the National Human Genome Research Institute. Today, sequencing a human genome costs about $ 1,000.
Doctors hoped to start using this advanced technology, called next-generation sequencing, to tailor treatment to specific patients. This field is known as “precision medicine”, a way for doctors to tailor treatments to specific patients.
But, as in many other aspects of American life, the coronavirus pandemic has revealed weaknesses in the system. Experts said that the lack of a national surveillance program for coronavirus variants was largely due to a lack of funding.
“It costs a certain amount of money to sequence each strain and I’m a novice investigator, I don’t have the money to pay for it,” said Bruce. “And people’s insurance won’t pay for it because it’s important information, but it won’t change the care of an individual patient.”
Sequencing an RNA virus is less expensive than sequencing an entire human genome, because they are much less complex organisms, but it is still much more expensive than a typical coronavirus test, running in the hundreds of dollars. This is because specialized work is needed to interpret the results – including molecular biologists and virologists like Bruce.
“This virus is here to stay,” said Mokdad. “We are not going to achieve collective immunity, we simply are not going to achieve it. It will be seasonal and it will be like the flu, and we will need to be ready for that, ”he said.
This leads to another potential need for vaccine manufacturers – vaccine updates to increase immunity to new variants. Moderna and Pfizer are already working on “reinforcement shots” for Covid-19 variants. Experts now recommend double masking to protect against the virus, along with a more vigilant social detachment.
Together, these developments left Mokdad certain of a result: “I am 100% sure in the winter [2021-22] we will have a sudden increase – but that will slow our decline. But I am convinced that this will happen. “