Britain: No link between covid-19 and Guillain-Barré

Researchers at University College London (UCL), led by Professor Michael Lan of the Institute of Neurology, who published the relevant publication on “Brain” magazine” (Brain), said their findings should reassure the public, as vaccinations against Covid-19.

The Guillain-Barre syndrome is a rare but serious autoimmune disease, which affects the peripheral nervous system, affecting the legs, arms and limbs in general, causing numbness, weakness and pain. Although its exact aetiology is unknown, the syndrome often occurs after a gastroenteritis infection with campylobacter, which results in the immune system attacking the nerves instead of the pathogens. Although the condition is usually reversible, in some severe cases it can lead to prolonged paralysis even in the respiratory muscles, resulting in the patient requiring mechanical respiratory support and permanent neurological damage.

More recently, the syndrome was associated with the Zika virus and then fears were expressed by some that it could also be caused after infection with the SARS-CoV-2 coronavirus. In 1976, during the mass vaccinations for swine flu, there was a slight increase in the incidence of this neurological syndrome, which led to the cessation of vaccination, although a subsequent statistical study concluded that the association between the influenza vaccine and Guillain-Barre syndrome was ultimately less than originally thought. Since then, in each influenza vaccination the risk of the syndrome is estimated to be only about one case per million doses of the vaccine.

In the new epidemiological study, UCL researchers found that there was no increase in cases of the syndrome in Britain during the first epidemic wave of Covid-19 in the spring. The annual incidence of the syndrome in UK hospitals between 2016-2019 was 1.65 to 1.88 cases per 100,000 people, and these cases were down by 40% to 50% between March-May 2020, in the midst of a pandemic, compared with 2016-19.

«There has been no increase in the incidence of the syndrome since the outbreak of the SARS-CoV-2 coronavirus pandemic, as was the case with the Zika virus epidemic. Our epidemiological study shows that there was no increase in the incidence of the syndrome during the first wave of Covid-19. Rather there was a decrease, therefore, we found no association between Covid-19 and Guillain-Barre syndrome,» said Dr Stephen Kenty of UCL.

Also, unlike the case of campylobacter which contains antigens similar to human antigens, which can trigger an autoimmune reaction, no similar protein was found in coronavirus that could cause a similar autoimmune reaction.

«Most vaccines for Covid-19 are based on the coronavirus spike protein, which triggers a complex immune response to create antibodies that fight the infection. Our analysis shows that SARS-CoV-2 does not contain any additional material that can trigger Guillain-Barre syndrome. Concerns that vaccination for Covid-19 could perhaps cause the syndrome in any significant number are therefore almost certainly unfounded,» Kenti said.

On the other hand, the researchers pointed out that, based on historical precedents, it is possible that the mass vaccination that has just begun could be blamed for some cases of the syndrome, which in fact will have occurred by chance and not because of the vaccine, since billions of people are expected to be vaccinated against coronavirus.

As Dr. Lan said, «when we immunize the population against Covid-19, Guillain-Barre syndrome and other neurological conditions will occur by chance and only in the weeks after vaccination. These cases may cause concern for patients, politicians and regulators, as well as reignite anti-vaccine concerns, although most, if not all, of these cases will likely not actually be related to the vaccine itself. Vaccination should not be postponed or stopped because of excessive safety concerns, unless it is actually statistically proven that there is a link between vaccines and the syndrome. We have to accept small risks in any vaccination programme of this scale and these risks are much smaller than the risk of Covid-19 infection.».