Is Leprosy back in the West?

Is leprosy a side effect of anti-COVID vaccines? This is the hypothesis put forward by a team of English researchers in a study published on August 4, after the discovery of a series of cases around the world, including two that occurred in the United Kingdom. What do the patients have in common? 98% of them had received between 1 and 3 doses of the Pfizer vaccine.

Should we be concerned or just add leprosy to the list of 1,291 types of adverse reactions of special interest that Pfizer had discovered as of March 2021?

MATHILDE DEBORD for THE CRITICAL POINT

Leprosy was believed to be eradicated from Western countries. A team of British researchers (de Barros et al. )  [1] today alerts to its resurgence in the United Kingdom, where several cases of indigenous contamination were recorded in 2021 while the country had been free from it since 1954 . Travelers or migrants from areas where leprosy remains endemic continue to be diagnosed in the United Kingdom, but no cases of contamination occurring on English soil in patients who have not been exposed to patients had been observed for nearly 70 years.

Study context

People with leprosy have a risk of reactions of immunological complications requiring the taking of immunosuppressive treatment. They are on this principle also at risk of developing a severe form of COVID-19 in the event of exposure to the virus. Because of these common risk factors, vaccination against COVID-19 is recommended in the UK for patients with leprosy, and more generally for immunocompromised people with the disease, who have been “benefited” from priority access vaccines from 2021.

However, although this is presented as purely theoretical, the risk of triggering or aggravating the clinical form of the disease by provoking an immunological response to a latent infection with the leprosy bacillus (Mycobacterium leprae) is a possible consequence of vaccination against COVID-19. This risk is also documented for BCG vaccination against tuberculosis, with some subjects having developed the disease from contact with people with leprosy within twelve weeks of receiving the vaccine.

Objective and results of the study

The authors carried out a retrospective study to determine the vaccination status of people diagnosed with leprosy who attended the Leprosy Clinic, the UK’s national clinical referral center for patients with the disease, in 2021. In particular, they looked at whether some people had developed leprosy or experienced a new leprosy reaction within twelve weeks of receiving a dose of the COVID vaccine.

Of the 52 people who attended the clinic in 2021, 49 had been vaccinated against COVID : 1 (2%) had received a single dose, 11 (22%) had received 2 injections and 30 (60%) had also received a booster dose. For 7 of them (14%), the vaccination schedule was not known. Two of them were diagnosed with leprosy, respectively one week after a second dose of Pfizer vaccine and eight weeks after a first dose of Pfizer vaccine, preceded by a double injection of Sinovac vaccine three months earlier.

Based on the definition used by the authors, they estimate that in these 2 cases (4%), leprosy could be considered a secondary effect of vaccination.

Additional data from the literature

The authors also carried out a census of the cases documented in the literature. They identified 14 people (in addition to the two patients in the study) who experienced adverse events from leprosy associated with COVID vaccines in six published reports, with the following characteristics:

• the patients came from endemic or non-endemic environments for leprosy: Italy, Taiwan, India, Singapore, Israel, Brazil, India, Indonesia ;
• these cases were all reported between 5 and 14 days after an injection ;
• ten of them (71.4%) experienced a leprosy adverse event after a 1st ^dose  , three after a 2nd ^dose  (21.4%) and one (7.2%) after a ^3rd  dose;
• in 4 cases (28.6%), the patients were already carriers of leprosy. In each of these cases, they have been associated with a leprosy reaction.

The authors specify that, based on a systematic review (Avallone et al. )  [2] of dermatological conditions caused by a severe inflammatory reaction observed after vaccination against SARS-CoV-2, that “the association between immune-mediated inflammatory complications of leprosy such as type 1 reaction (T1R), erythema nodosum (ENL) and neuritis and vaccination against SARS-CoV-2 are consistent with T cells, cytokines and other immune responses elicited by vaccines ”.

In other words, the cases of leprosy presented in the study are consistent with the currently known mechanism of action of the vaccine.

The study was published August 4, 2023 in the peer-reviewed journal PLoS Neglected Tropical Diseases. In accordance with the practice imposed for 2 years in the scientific press, the researchers specify that the results of the study do not call into question the benefit of vaccination.

Should we be worried?

The authors point out that the infection is curable with antimicrobial treatment. The MSD Manual states that it is not highly contagious, rarely fatal, and can be effectively treated with antibiotics, but is associated with often significant disability and psychological impact.

However, they also wish to draw attention to the incidence found in this study, which was evaluated at 2 cases out of 50, or 4% . By comparison, BCG was associated with the development of leprosy in only 0.33% of healthy contacts of people with leprosy within 12 weeks of administration.

It is obviously premature and excessive to conclude that the vaccination against COVID has allowed leprosy to return to the West, but this publication reminds us that two years after the injections were deployed, we are still discovering new potential side effects. The Pfizer laboratory had established in March 2021, at the end of the first months of vaccination, a document that we were not supposed to see before 75 years, listing 1,291 adverse events of particular interest (AESI), that is, which it felt should be followed carefully…

Health authorities have never paid attention to this list, which says nothing about the frequency of these adverse events or their connection to the vaccine (except that they were identified by the laboratory itself). However, neither turbo cancers, the incidence of which today makes oncologists dizzy, nor leprosy are part of it.

What is this revolutionary technology that may have enabled the West to return to the Middle Ages, that is to say to the antipodes of this promise?

References

[1] de Barros B, Pierce R, Sprenger C, Ong ELH, Walker SL. COVID-19 vaccination and leprosy–A UK hospital-based retrospective cohort study. PLoS Negl Trop Dis. 2023 Aug 4;17(8):e0011493. DOI: https://www.doi.org/10.1371/journal.pntd.0011493.

[2] Avallone G, Quaglino P, Cavallo F, Roccuzzo G, Ribero S, Zalaudek I, et al. SARS-CoV-2 vaccine-related cutaneous manifestations: a systematic review Int J Dermatol. 2022 Oct;61(10):1187-1204. DOI: https://doi.org/10.1111/ijd.16063.

************

Source