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Source: COVID-19 Vaccines   Oct 08, 2020  21 days ago
MUST READ! Study Involving Case Of Reinfection Questions Efficacy Of COVID-19 Vaccines Under Development Or Trials Against Emerging Mutated Strains
MUST READ! Study Involving Case Of Reinfection Questions Efficacy Of COVID-19 Vaccines Under Development Or Trials Against Emerging Mutated Strains
Source: COVID-19 Vaccines   Oct 08, 2020  21 days ago
COVID-19 Vaccines: A group of American researchers from  the Swedish Medical Center-Seattle, University of Washington-Seattle, Stanford University-California, LabCorp-Seattle and the Vaccine and Infectious Disease Division, Fred Hutch-Seattle after reviewing a case of a patient who got re-infected with a different strain of the SARS-CoV-2 coronavirus ie the more potent and infectious D614G mutated strain are now questioning the effectiveness of the current vaccines that are under development or in phase 3 trials.



The case patient had anti-SARS-CoV-2 IgG antibodies in the first weeks after reinfection, but notably, levels of anti-RBD IgG were relatively low, with no evidence of blocking antibodies to the RBD-ACE2 complex. ACE2 blocking increased only slightly by day 42, likely due to IgA antibodies. In the B cell repertoire, new clones do not emerge by day 18 after reinfection, lending support to immune recognition of prior infection or suggesting a deficiency in the developing response to the reinfection. 

While the nAb titers immediately at the time of reinfection are not known, by day 14 after reinfection, nAb levels were comparable to those observed after boosted vaccination.21 By day 42 nAb response showed a 1.5-fold increase to Wuhan pseudovirus, and a 2.6- fold increase to D614G pseudovirus. 

Taken together, these findings suggest that poorly developed or waned antibodies against the D614 virus formed after primary infection in March were not protective against reinfection with the D614G spike variant acquired in July. 

These results could have important implications for the success of vaccine programs based on the Wuhan strain.

The study findings cum report are published on a preprint server and are currently being peer-reviewed. https://www.medrxiv.org/content/10.1101/2020.09.22.20192443v1

According to the study team the patient from a Seattle nursing home tested positive for a mutated strain a few months after recovering from an earlier variety. Findings suggest that the antibodies formed after the first infection did not offer strong protection against the second.

The researchers say that the case findings from this reinfection could have implications for vaccine development and those that are currently in phase 3 trials.

Although other scientists who are involved in the current vaccines say that the mutated strain of the coronavirus in the study so far does not appear to have a big effect, they do not seen to have facts to back up their claims against this research findings.

The female patient in the study was from Seattle and fell severely ill in March after contracting the virus with genes linked to the first strains of Sars-CoV-2, the official name of the coronavirus, detected in the central Chinese city of Wuhan.

In late August, the patient returned to the hospital with a different strain of the virus carrying D614G, a mutation that was not seen in the first infection.

Dr Jason Goldman from the Swedish Medical Centre in Seattle told Thailand Medical News, “These results could have important implications for the success of vaccine programmes based on the original Wuhan strain.”

Dr Goldman’s team said their patient was a nursing home resident in he r sixties who might have first caught the virus from a staff member who returned from the Philippines with a respiratory infection.

In late March, the patient was hospitalized for over a month with severe pneumonia associated with COVID-19, the disease caused by the coronavirus.

Upon recovering, the patient went to a new nursing facility where several other residents had coughs. In August, after two weeks with a dry cough and general weakness, the patient was sent back to hospital and tested positive again, this time for the coronavirus strain with the D614G mutation.

Professor Dr Chen Wei, a virologist with the Academy of Military Medical Sciences and a scientist leading China’s COVID-19 vaccine programme based on the Wuhan strain warned that mutated strains that are fast emerging and becoming prevalent are going to be a problem despite denials from Western researchers involved in current vaccines.

Dr Chen told the Global Science and Life Health Forum in Beijing earlier this month that every day her team monitored the international database of viral genomes sequenced in different countries.

Dr Chen said researchers were trying to determine the structural or functional changes caused by these mutations, including D614G, which occurred in almost every sequence recently updated from around the globe.

She said, “Although Western researchers are saying that the impact of D614G is estimated to be very small, there are no detailed studies to support this.” she said. Furthermore there are even more newer strains emerging with some like the V483G strain that are antibody resistant already starting to gain prevalence in certain communities. https://www.thailandmedical.news/news/v483g-mutation-warning-about-growing-prevalence-of-new-sars-cov-2-mutant-strain-v483g-that-is-antibody-resistant-and-even-more-infectious

She admitted without wanting to get into details that the Chinese vaccine programmes have already admitted these shortcomings and are trying to find ways to rectify it.

Dr Goldman and his colleagues found the Seattle patient’s immune cells took 18 days longer than expected to respond to the second infection, which might suggest “a deficiency in the developing response to the reinfection”.

The antibodies developed during the second infection also had a stronger response to the D614G mutant variety than the Wuhan strain.

The researchers said these were signs that the antibodies formed after the first infection did not offer strong protection against the second infection.

The study team said, “Taken together, these findings suggest that poorly developed or waned antibodies against the D614G virus formed after primary infection in March were not protective against reinfection with the D614G spike variant acquired in July.”

The symptoms of reinfection however such as fever were less severe in the Seattle patient.

There are currently a growing number of documented reinfections growing globally.

Such cases of reinfection with mutated strains could have implications for vaccines because nearly all the vaccines close to mass application were developed based on the coronavirus genome sequenced and released by Chinese scientists in January. (This applies for all the vaccines in the phase 3 trials that are expected to be approved for use in various populations around the world anything at the end of this year or early next year.)

To date more than 200,000 volunteers throughout China, including diplomats, engineers and workers sent overseas, have already been given shots of vaccine candidates, according to Chinese authorities.

The initial hope is that antibodies from the vaccines will offer sustained protection against reinfection and various strains but emerging data is showing that that might not necessarily be the case.

A recent Australian silico study claimed that the vaccines being currently developed will not be affected by the mutated  strains  especially the D614G mutated strain but many are questioning the validity of this study and whether they were lobbied by the various biotech and pharma companies who have billions of dollars at stake to come up with this study https://www.nature.com/articles/s41541-020-00246-8

Another team of US military scientists involved with the current vaccines said widespread mutations such as D614G were rare when studies are showing the complete reverse!

There is lack of transparency in the development research and clinical trials of many of the current vaccines under developments or in clinical trials and the Trump administration and operation Warp speed handled by Mike Spence and Nick Ayers that is being influenced by a group of businessmen (led by Tom Cahill) from outside the white house according the certain American media is a reason for this.

For more on COVID-19 Vaccines, keep on logging to Thailand Medical News.

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