Vaccine Info

Bacille Calmette-Guerin (BCG) Vaccine

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Last reviewed
April 6, 2021

BCG Vaccine Description

Bacille Calmette-Guerin (BCG) vaccine is an attenuated, live culture preparation of the Bacillus of Calmette and Guerin (BCG) strain of Mycobacterium Bovis. The TICE® strain used in this BCG vaccine preparation was developed at the University of Illinois from a Pasteur Institute strain.

BCG is a vaccine (VPM1002) against tuberculosis, with protective non-specific effects against other respiratory tract infections and in vivo studies, and reported morbidity and mortality reductions as high as 70%. Mycobacterium tuberculosis (Mtb), the ethiological agent of tuberculosis (TB).

Many foreign-born persons have been BCG-vaccinated. For example, India introduced BCG in mass immunization with its highest TB burden in 1948.

TB is the leading cause of death from infectious disease worldwide, causing about 1.3 million deaths per year, mostly in the developing world. The respiratory virus M tuberculosis is spread via airborne transmission and more often affects men, who account for 60% of all cases, according to a recent study published by the CDC in May 2020.

There were an estimated 2.5 million TB cases in the African Region in 2019, accounting for 25% of the global burden. More than 500,000 African lives are lost to TB every year, reported the World Health Organization (WHO).

Newborns and infants have the greatest benefit from BCG vaccination. The WHO recommends routine neonatal vaccination in countries with moderate to severe tuberculosis prevalence. The reduction in childhood mortality may be due to epigenetic reprogramming of the nucleotide-binding oligomerization domain receptor.

This is because of suggestions the BCG vaccine has other beneficial effects on the immune system that could protect against other infections. A 2019 observational study reported that the vaccine is related to fewer deaths from certain infections other than TB in low-income countries.

The biological interaction between Mtb and the human host is complex and only partially understood, says the WHO.

The U.S. NIH says the BCG vaccine is fairly safe, not associated with severe complications.

Merck's version of the TICE® BCG organism is grown to prepare the freeze-dried cake in agar composed of the following ingredients: glycerin, asparagine, citric acid, potassium phosphate, magnesium sulfate, and iron ammonium citrate. The final preparation before freeze-drying also contains lactose. The freeze-dried BCG preparation is delivered in vials, each containing 1 to 8 x 10^8 colony-forming BCG units, equivalent to approximately 50 mg of wet weight. Determination of in-vitro potency is achieved through colony counts derived from a serial dilution assay. Intradermal guinea pig testing is also used as an indirect measure of potency.

BCG Vaccine History

The WHO recommends neonatal BCG vaccination in countries or settings with a high incidence of tuberculosis.

The BCG vaccine is not generally recommended for use in the USA because of the low risk of infection with Mycobacterium tuberculosis, says the CDC. BCG should only be considered for very select people who meet specific criteria and consult a TB expert.

And recently, a non-peer-reviewed study published on June 12, 2020, found that mandatory BCG vaccination was associated with a significantly slower climb in both confirmed cases and deaths during the first 30-day period of an outbreak. Furthermore, a study published on July 31, 2020, found linear mixed models revealed a significant effect of mandated BCG policies on the growth rate of both cases and deaths after controlling for median age, gross domestic product per capita, population density, population size, net migration rate, and various cultural dimensions.

The BCG Atlas is an open-source database of global BCG vaccination policies and practices founded in 2011. Drugbanks Accession Number is DB12768; UNII: 8VJE55B0VG; ATC code: J07AN01.

BCG Vaccine Indication

The BCG vaccine is used in many countries to prevent childhood tuberculous, meningitis, bladder cancer, and other diseases. The BCG vaccine also helps fight other viruses, such as respiratory infections. TB is a serious infection that affects the lungs and other parts of the body, such as the bones, joints, and kidneys. 

BCG has been one of the most successful immunotherapies and has been the "standard of care for patients with bladder cancer" since 1977.

For example, one study conducted in West Africa found that vaccinated children with BCG had about a 50% reduction in overall mortality, largely because it reduced respiratory infections, sepsis, or blood poisoning.

A study published on May 2, 2019, reported the effect of BCG on an experimental viral infection in humans had been demonstrated. These effects are thought to be mediated via the induction of innate immune memory and heterologous lymphocyte activation, resulting in enhanced cytokine production, macrophage activity, T-cell responses, and antibody titers.

In the USA, BCG vaccination should be considered for select persons who meet specific criteria and consult with a TB expert, says the CDC. Also, BCG vaccination should not be given to immunosuppressed persons (e.g., persons who are HIV infected) or persons who are likely to become immunocompromised (e.g., candidates for organ transplant).

BCG vaccination should only be considered for children who have a negative tuberculin skin test and are continually exposed. It cannot be separated from untreated or ineffectively treated adults for TB disease or have TB caused by strains resistant to isoniazid and rifampin.

Furthermore, BCG vaccination should not be given during pregnancy. Even though no harmful effects of BCG vaccination on the fetus have been observed, further studies are needed to prove its safety.

BCG vaccination may also be recommended for older children who have an increased risk of developing TB, such as children who have recently arrived from countries with high levels of TB, including those in Africa, the Indian subcontinent, parts of southeast Asia, parts of South and Central America, and parts of the Middle East, and children who have come into close contact with somebody infected with respiratory TB.

A single dose of M. Bovis bacillus Calmette-Guérin immunotherapy has a great therapeutic benefit in treating a non-invasive form of bladder cancer. It is administered intravesically, and proven benefits include the malignancy's delay and prevention of progression.

The BRACE phase 3 clinical trial, last updated on October 22, 2020, intends to recruit about 10,000 healthcare workers in the UK, Australia, the Netherlands, Spain, and Brazil.

BCG Vaccine and Cancer

Bacillus Calmette-Guerin is the most common intravesical immunotherapy for treating early-stage bladder cancer. It's used to help keep cancer from growing and help keep it from coming back, says BCG is a germ related to the one that causes tuberculosis, but it doesn’t usually cause serious disease.

BCG is put right into the bladder through a catheter. It reaches the cancer cells and "turns on" the immune system. The immune system cells are attracted to the bladder and attack the bladder cancer cells. BCG must come in contact with the cancer cells to work.

On March 13, 2019, Merck stated it 'recognizes the impact the current availability of TICE BCG (BCG LIVE FOR INTRAVESICAL USE) is having on patients and their caregivers and today provided an update on the company’s long-term commitment to maintain increased production of and access to TICE BCG, a medicine for the treatment of certain forms of bladder cancer.'

On January 8, 2020, Merck announced that the U.S. Food and Drug Administration had approved KEYTRUDA, Merck’s anti-PD-1 therapy, as monotherapy for the treatment of patients with Bacillus Calmette-Guerin (BCG)-unresponsive, high-risk, non-muscle-invasive bladder cancer with carcinoma in situ with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy.

BCG Vaccine and COVID-19

The WHO stated in April 2020, 'There is no evidence that the Bacille Calmette-Guérin vaccine protects people against infection with COVID-19 virus.'

On April 6, 2020, researchers at the Johns Hopkins Bloomberg College of Public Well discovered that the COVID-19 mortality fee amongst countries that use the Bacillus Calmette-Guérin vaccination was eight instances lower than in those that don’t. However, there are active late-stage clinical trials in the USA, Australia, and the Netherlands evaluating the potential protective benefits from BCG vaccination related to COVID-19 disease prevention.

On November 20, 2020, a study by Cedars-Sinai in Los Angeles, California, raised the possibility that the BCG vaccine may help prevent coronavirus infections or reduce the disease's severity. In the new study, published in The Journal of Clinical Investigation, investigators tested the blood of more than 6,000 healthcare workers in the Cedars-Sinai Health System for evidence of antibodies to SARS-CoV-2, the virus that causes COVID-19, and also asked them about their medical and vaccination histories. They found that workers who had received BCG vaccinations in the past—nearly 30% of those studied—were significantly less likely to test positive for SARS-CoV-2 antibodies in their blood or to report having had infections with coronavirus or coronavirus-associated symptoms over the prior six months.

BCG Vaccine Dosage

The WHO Expert Committee first considered the formulation of international requirements to manufacture and control the BCG vaccine on Biological Standardization in its thirteenth report.

Approved dose: BCG vaccine can be given either cutaneously or intradermally. Research is currently being conducted on respiratory administration since natural infection and sensitization to Mycobacterium tuberculosis in humans tend to occur in the respiratory system.

The intact vials of BCG VACCINE should be stored refrigerated at 2–8°C (36–46°F). This agent contains live bacteria and should be protected from direct exposure.

BCG Vaccine News

April 7, 2021 - The WHO stated 'Those in the highest economic quintile are five times more likely to deliver their babies in health facilities and have their babies vaccinated with BCG compared to those in the lowest quintile.'

March 24, 2021 - GAVI reported, 'Despite the universal vaccination of neonates and infants in TB-endemic countries, Mycobacterium tuberculosis still kills more people worldwide than any other infectious pathogen – approximately 1.4 million deaths each year. Approximately a quarter of the world’s population is infected with it, of whom 5-10% will develop TB disease during their lifetimes. '

March 23, 2021 - Study: BCG Vaccine-Induced Trained Immunity and COVID-19: Protective or Bystander? This review focuses on BCG-related cross-protection and acquisition of trained immunity, as well as the correlation between BCG vaccination and COVID-19 incidence and mortality.

March 22, 2021 - The ECDC published Tuberculosis surveillance and monitoring in Europe 2021 –2019 data. This report provides an overview of the latest TB epidemiological situation. It is published jointly by the WHO Regional Office for Europe and the European Centre for Disease Prevention and Control.

March 9, 2021 - At the Ukraine Ministry of Health's request, the United Nations Children’s Fund (UNICEF) delivered 450,000 BCG vaccines to protect children from tuberculosis. UNICEF procured these vaccines. This BCG vaccine is manufactured by the Serum Institute of India and is pre-qualified by the WHO. Later, Ukraine will receive another 640,000 doses. According to the Public health Centre of Ukraine, 88.8% of children under one year of age were vaccinated against tuberculosis in 2020.

February 23, 2021 - The Lancet article: Quantifying the global number of tuberculosis survivors: a modeling study. The number of tuberculosis survivors alive in 2020 is more than ten times the estimated annual tuberculosis incidence. Interventions to alleviate respiratory morbidity, screen for and prevent recurrent tuberculosis, and reduce stigma should be immediately prioritized for recently treated tuberculosis survivors.

February 17, 2021 - The Lancet published a new 'BCG-induced non-specific effects on heterologous infectious disease in Ugandan neonates: an investigator-blind randomized controlled trial.' This study investigated whether BCG altered all-cause infectious disease morbidity in healthy infants in a different high-mortality setting (west Africa) and explored whether the changes are mediated via trained innate immunity. Study Interpretation: BCG vaccination protects against non-tuberculous infectious diseases during the neonatal period, in addition to having tuberculosis-specific effects. Prioritizing BCG on the first day of life in high-mortality settings might have significant public health benefits by reducing all-cause infectious morbidity and mortality.

February 17, 2021 - In The Lancet Infectious Diseases, Sarah Prentice and colleagues report that BCG's tuberculosis vaccine protects against non-tuberculous infectious diseases. Trials done in infants with low birthweight in West Africa suggest that BCG vaccination reduces all-cause mortality in the neonatal period, probably because of heterologous protection against non-tuberculous infections. This study investigated whether BCG altered all-cause infectious disease morbidity in healthy infants in a different high-mortality setting and explored whether the changes are mediated via trained innate immunity.

February 11, 2021 - The University of Szeged's research team found 802 common protein fragments between the BCG vaccine and the SARS-CoV-2 virus that causes COVID-19 infection, which may play a role in the immune response against the virus. The results of a paper published in the prestigious journal Clinical and Translational Immunology may be important in elucidating the immunological link between BCG vaccination and COVID-19 disease.

February 5, 2021 - Healthcare workers are at the frontline of the coronavirus disease (COVID-19) pandemic. They will be randomized to receive a single dose of BCG vaccine or 0.9% NaCl placebo. Participants will be followed up for 12 months with a notification from a Smartphone application or phone calls (up to daily when ill) and surveys to identify and detail COVID-19 infection. Additional information on the severe disease will be obtained from hospital medical records and/or government databases. Blood samples will be collected before randomization and at 3, 6, 9, and 12 months to determine exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Where required, swab/blood samples will be taken at illness episodes to assess SARS-CoV-2 infection.

Jan. 27, 2021 - Merck announced that the Board of Directors had approved plans to construct a new manufacturing facility to significantly expand production capacity for TICE® BCG (BCG Live For Intravesical Use), a medicine for the treatment of certain forms of bladder cancer. Since Merck unexpectedly became the only manufacturer of BCG for patients in many countries worldwide in 2012, increasing global demand has outpaced our current maximum manufacturing capabilities. Once this new facility is fully operational, we will triple its current manufacturing capacity, which is expected to support the anticipated demand for TICE BCG for the foreseeable future. The new facility will be part of the existing Maurice R. Hilleman Center for Vaccine Manufacturing in Durham, North Carolina.

January 19, 2021 - According to Dr. Camille Locht, research director of Inserm at the Institut Pasteur de Lille, the BCG vaccine's mechanism has to do with the innate immune system. “The BCG can train the cells of the innate immune system to make them more fit and active to fight against other diseases. This is why we think that by training the immune system with BCG, it will have a protective effect against organisms that have nothing to do with tuberculosis or BCG,” Dr. Locht told RFI.

December 31, 2020 - India has dispatched a supply of 2,400 vials of BCG vaccine to Male to bridge a shortfall in the Maldives' National Immunization Programme. The Ministry of Health and Ministry of External Affairs of the Government of India procured the vaccine and coordinated its dispatch with the High Commission of Maldives in Delhi, the Honorary Consul of Maldives Mumbai, the Maldivian Ministry of Foreign Affairs. 

December 21, 2020 — ImmunityBio, Inc. announced positive data from the first cohort of a pivotal Phase 2/3 trial (QUILT 3.032) for non-muscle invasive bladder cancer in high-risk carcinoma in situ (CIS) disease. The data showed 51 out of 71 evaluable patients (72%) had a complete response (at any time) to intravesical BCG plus N-803 (Anktiva), with 59% probability of these patients maintaining a complete response for at least 12 months, with a median duration of complete response of 19.2 months to date. With the observed efficacy and only 1% of patients reporting treatment-emergent serious adverse events, but none of which were treatment-related, the data support the potential for Anktiva plus BCG as a novel option for BCG unresponsive CIS, a therapeutically challenging disease. Patients with BCG unresponsive CIS disease face surgical removal of the bladder, a procedure fraught with high morbidity and mortality.

December 11, 2020 - BCG has long been known for its non-specific beneficial effects, most likely explained by epigenetic and metabolic reprogramming of innate immune cells, termed trained immunity. In this issue of the JCI, Rivas, et al. add to these arguments by showing that BCG-vaccinated healthcare providers from a Los Angeles healthcare organization had less COVID-19 diagnosis and serology than unvaccinated individuals. Prospective clinical trials are thus warranted to explore BCG effects in COVID-19. We posit that beyond COVID-19, vaccines that elicit trained immunity, such as the BCG, may mitigate the impact of emerging pathogens in future pandemics. Almost one-third of the volunteers participating in the study had received earlier BCG vaccination, accompanied by a marked decrease (by approximately 30-40%) of self-reported COVID-19 diagnoses, self-reported positive COVID19 RT-PCR tests, and anti-SARS-CoV-2 specific serology. BCG vaccinations were associated with lower COVID-19 incidence, although the vaccinated group was slightly older and had more co-morbidities.

December 11, 2020 - The UN Tuberculosis High-Level Meeting Political Declaration, signed in October 2018 by more than 100 government and 360 civil society representatives, committed to treating 3·5 million children with tuberculosis by 2022. To this end, more children must be diagnosed. Although an estimated 12% of all tuberculosis disease is in children younger than 15 years, in 2019, only 8% of notifications involved children, a proportion that is even lower in some high-burden countries, and 16% of tuberculosis deaths occurred in this age group. Altogether, these numbers suggest substantial barriers to diagnosis and timely treatment of childhood tuberculosis and under-reporting because of difficulties in the case definition.

December 9, 2020 - Based on the capacity of BCG to (1) reduce the incidence of respiratory tract infections in children and adults; (2) exert antiviral effects in experimental models; and (3) reduce viremia in an experimental human model of viral infection, we hypothesize that BCG vaccination may induce (partial) protection against the susceptibility to and/or severity of SARS-CoV-2 infection. This phase III randomized controlled trial provides the highest validity to answer this research question. Given the SARS-CoV-2 epidemic's immediate threat, the trial has been designed as a pragmatic study with a highly feasible primary endpoint, which can be continuously measured. This allows for the most rapid identification of a beneficial outcome that would allow other at-risk individuals, including the control population, to benefit from the intervention if and as soon as it has demonstrated efficacy and safety.

December 9, 2020 - Study: These data show BCG vaccination is safe and can protect the elderly against infections. Randomized controlled trials are underway in the Netherlands and Australia to assess whether the BCG vaccine reduces the incidence and severity of COVID‐19 in healthcare workers. Still, the ACTIVATE trial gives some hope that BCG could protect the elderly against COVID‐19.

December 4, 2020 - Study: Unlike many adjuvants, BCG decreases the incidence of lymphoid malignancies, and its effect on various autoimmunopathies is different, not necessarily harmful. The BCG vaccination effect's peculiar character may be related to its early impact on immature immune systems and host-BCG interactions' symbiotic character. Geo-epidemiological data on the relationship between the historical practice of using BCG vaccination in different countries and the current incidence of new coronavirus infection and mortality from it are presented. Historically, the medical and social reasons for the different national policies of health authorities regarding the use of the BCG vaccine are considered.'

November 20, 2020 - A widely used tuberculosis vaccine is associated with a reduced likelihood of contracting COVID-19 (coronavirus). The findings raise the possibility that a vaccine already approved by the U.S. Food and Drug Administration may help prevent coronavirus infections or reduce the disease's severity. The vaccine, known as Bacillus Calmette-Guérin (BCG), was developed between1908 and 1921 and is administered to more than 100 million children worldwide every year. In the U.S., it is FDA-approved as a drug to treat bladder cancer and as a vaccine for people at high risk of contracting TB. The BCG vaccine is currently being tested in multiple clinical trials worldwide for effectiveness against COVID-19.

November 19, 2020 -  The Journal of Clinical Investigation published a Cedars-Sinai Health System study for evidence of antibodies to SARS-CoV-2 and found that workers who had received BCG vaccinations in the past—nearly 30% of those studied—were significantly less likely to test positive for SARS-CoV-2 antibodies in their blood or to report having had infections with coronavirus or coronavirus-associated symptoms over the prior 6-months than those who had not received the BCG vaccine. "It appears that BCG-vaccinated individuals either may have been less sick and therefore produced fewer anti-SARS-CoV-2 antibodies, or they may have mounted a more efficient cellular immune response against the virus," said Arditi, professor of Pediatrics and Biomedical Sciences. "We were interested in studying the BCG vaccine because it has long been known to have a general protective effect against a range of bacterial and viral diseases other than TB, including neonatal sepsis and respiratory infections."

November 17, 2020 - A new study published by The Lancet found 'Patients with high-risk non–muscle-invasive tumors that do not respond to adjuvant therapy with the standard-of-care immunotherapy, Bacille Calmette-Guérin (BCG), constitute a challenging patient population to manage and many alternative therapies are being studied. While intravesical BCG has remained the mainstay of therapy for intermediate and high-risk non–muscle-invasive bladder cancer, the therapeutic options for the muscle-invasive and advanced disease have expanded to include immunotherapy with checkpoint inhibition, targeted therapies, and antibody-drug conjugates.'

November 5, 2020 - Researchers of a trial by Parel's Haffkine Research Institute and BJ Medical College, Pune, conducted on 60 Covid patients hospitalized with breathlessness and pneumonia claimed to have found a reduction in oxygen requirement from the third or fourth day and improved x-rays and CT scan from day 7-15. There were no deaths in the arm that got the BCG shot, while there were two deaths in a group that got a standard line of care.

October 11, 2020 - The University of Exeter is leading the UK arm of the trial, called the BCG vaccination to Reduce the impact of COVID-19 in healthcare workers' (BRACE) Trial. The UK joins study centers in Australia, the Netherlands, Spain, South Africa, and Brazil in the largest trial of its kind. “BCG has been shown to boost immunity in a generalized way, which may offer some protection against COVID-19,” stated Professor John Campbell of the University of Exeter Medical School. 

October 3, 2020 - Texas A&M researchers are looking into a potential vaccine that may help with COVID-19. In addition to the medical professionals that have participated in the BCG vaccine study, more first responders such as firefighters and police officers can now see if they are eligible for the study.

September 24, 2020 - The BCG vaccine may be a potential, safe, affordable, and readily available candidate intervention to decrease the high burden of disease associated with HSV infection and recurrences, but properly controlled randomized trials are required. In animals, BCG administration led to a 1.9 to 5.5‐fold increase in survival rate following HSV challenge (vaginal, corneal, or intraperitoneal inoculation).

September 24, 2020 - Fiocruz and the Murdoch Children’s Research Institute in Australia announced they would begin testing the BCG vaccine on 3,000 healthcare professionals to verify the immunizer's protection against Covid-19. The trial, which was initially expected to be carried out only in Mato Grosso do Sul, will be expanded to Rio de Janeiro. Coordinated in Brazil by Fiocruz researchers Julio Croda and Margareth Dalcolmo, the National Committee approved the research of Ethics in Research.

September 21, 2020 - Harvard Medical School updated a phase 3 study: The purpose of this study is to assess the efficacy of Bacille Calmette-Guérin (BCG) vaccination compared to placebo in reducing severe Covid-19 disease among elderly residents of skilled nursing facilities.

September 21, 2020 - Usually, non-randomized studies can provide evidence only of correlations, not actual causation. But the type of analysis that the Chaisemartins applied is different. “The regression discontinuity method we used is considered almost as reliable as a randomized controlled trial in terms of teasing out correlation from causation."

August 23, 2020 - Study: Using information from the Swedish public health agency, researchers determined that 'While the effect of a recent vaccination must be evaluated, we provide strong evidence that receiving the BCG vaccine at birth does not have a protective effect against COVID-19 among middle-aged individuals.'

August 22, 2020 - The BMC will conduct a BCG vaccine trial among 250 seniors in India as per the Indian Council of Medical Research recommendations.

August 19, 2020 - In this issue of the JCI, Koeken and de Bree et al. report that BCG reduces circulating inflammatory markers in males but not in females, while de Bree and Mouritis et al. describe how diurnal rhythms affect the degree of BCG-induced innate memory. These studies further delineate factors that influence the magnitude of responses to BCG and may be crucial to harnessing its potential benefits.

August 17, 2020 - "It has been known for years that some vaccines can offer protection against diseases that they're not targeting against. The best example is the BCG vaccine used to prevent tuberculosis. It can prevent people from acquiring malaria," said Andrew Bradley, the Mayo Clinic COVID Research Task Force Chair. Bradley says the best theory is called immune training – that is, your body, in preparing to defend itself from one disease, unintentionally protects it from another.

August 11, 2020 - Our findings demonstrated the booster BCG vaccine's potential effectiveness, specifically the booster in preventing Covid-19 infections in an elevated-risk healthcare population.

August 5, 2020 - A new analysis suggests that mandated BCG vaccination can effectively fight against COVID-19.

July 28, 2020 - This epidemiological study assessed the global linkage between BCG vaccination and COVID-19 mortality. Signals of BCG vaccination effect on COVID-19 mortality are influenced by social, economic, and demographic differences between countries. After mitigating multiple confounding factors, several significant associations between BCG vaccination and reduced COVID-19 deaths were 'observed.' In various European countries, BCG vaccination indicated that every 10% increase in the BCG index was associated with a 10.4% reduction in COVID-19 mortality. However, these results fail to confirm the null hypothesis of no association between BCG vaccination and COVID-19 mortality and suggest that BCG could have a protective effect. 

July 20, 2020 - ICMR studies the BCG tuberculosis vaccine's efficacy against COVID-19 among the elderly. Approximately 1,500 healthy volunteers above 60 years of age will be administered one dose of 0.1ml BCG vaccine intradermally and followed up closely for a period of six months.

July 18, 2020 - The National Institute for Research in Tuberculosis in Chennai has initiated a multi-centric study to investigate whether the Bacille Calmette Guerin (BCG) vaccine can prevent and/or reduce the severity of COVID-19 disease among elderly individuals aged 60 years and above residing in hotspots for SARS-CoV2.

July 14, 2020 - Based on the ACTIVATE study's interim analysis, findings showing a 53% decrease in the incidence of all new infections with BCG vaccination.

July 9, 2020 - Researchers at the National Institute of Allergy and Infectious Diseases of the U.S. NIH identified an 'associated' linkage between the ancient Bacille Calmette-Guerin (BCG) and the reduction in COVID-19 disease after comparing mortality rates around the world. 

July 3, 2020 - Researchers at the University of Sydney and Centenary Institute are repurposing an existing tuberculosis vaccine Bacille Calmette-Guérin (BCG), with major components SARS-CoV-2 virus, creating a new vaccine candidate called BCG: CoVac. In BCG: CoVac, the BCG vaccine is used as a vehicle to deliver distinctive proteins that originate from the SARS-CoV-2 virus surface. The goal is for the human immune system to develop a memory of SARS-CoV-2 and develop immunity.

June 17, 2020 - The latest survey results of Global Fund-supported programs across 106 countries show widespread disruptions to TB vaccine service delivery due to the COVID-19 pandemic: 78% of TB programs reported disruption BCG vaccination services (17% with high or very high disruptions).

June 12, 2020 -  A non-peer-reviewed study found that mandatory BCG was associated with a significantly slower climb in both confirmed cases and deaths during the first 30-day period of an outbreak. This analysis suggests that mandated BCG vaccination can effectively fight against COVID-19.

June 11, 2020 - The Washington Post wrote, 'Can old vaccines from science's medicine cabinet ward off coronavirus? ... Prominent researchers hope to test the vaccine against the coronavirus.'

May 28, 2020 - Bulgarian scientists suggest that the Balkan country's high rate of BCG vaccination—as well as an early lockdown—helped it to escape the worst of the pandemic. "BCG generates a powerful immune stimulation.

May 27, 2020 - A Phase III, two-group multicentre, randomized controlled trial in up to 10,078 healthcare workers to determine if BCG vaccination reduces the incidence and severity of COVID-19 disease.

May 26, 2020 - The NIH published a Bacillus Calmette Guerin (BCG) summary by Chika N. Okafor; Ayesan Rewane; Ifeanyi I. Momodu.

May 25, 2020 - A vaccine developed by Pune's Serum Institute of India (SII) is currently being tested at several Pune hospitals like - Ruby Hall, KEM Pune, Jehangir Hospital. The serum is carrying out phase 3 clinical trials of the Recombinant-BCG vaccine in 30 locations across the nation, as per reports.

May 20, 2020 - Researchers at Baylor College of Medicine and four other institutions worldwide are working to determine if it can also work against COVID-19. They are now recruiting for a clinical trial to test the vaccine. “Epidemiological studies show that if you’re BCG vaccinated, you have a decreased rate of other infections,” said Dr. Andrew DiNardo, assistant professor of medicine – infectious diseases at Baylor.

May 19, 2020 - Can the BCG vaccine protect against COVID-19?

May 13, 2020 - A study published in JAMA does not support the idea that BCG vaccination in childhood has a protective effect against COVID-19 disease later in adulthood. In this cohort of Israeli adults aged 35 to 41 years, BCG vaccination in childhood was associated with a similar rate of positive test results for SARS-CoV-2 compared with no vaccination.

May 7, 2020 - Texas A&M University researchers vaccinated more than 50 health care workers on Wednesday as they started a clinical trial for a vaccine they believe can mitigate the effects of COVID-19. The BCG vaccinations administered at the Bryan Medical Center were the first in the U.S. clinical trial. BCG won’t prevent people from contracting COVID-19. Still, researchers believe it may allow a person’s immune response to kill nearly any type of infection, meaning it essentially broadly strengthens people’s immune response.

May 4, 2020 - Researchers at Baylor College of Medicine and 4 other institutions worldwide are working to determine if the BCG vaccine can work against COVID-19. They are now recruiting for a clinical trial to test the vaccine.

April 30, 2020 - An article published in The Lancet says 'If the BCG vaccine or another inducer of trained immunity provides non-specific protection to bridge the gap before a disease-specific vaccine is developed, this would be an important tool in response to COVID-19 and future pandemics.'

April 29, 2020 - This Phase 3 study evaluates BCG's efficacy to improve the clinical course of Covid-19 infection and prevent absenteeism from safeguarding continuous patient care.

April 28, 2020 - Dr. Jeffrey Cirillo at the Texas A&M Health Science Center is leading a group of world-renown institutions in a vaccine clinical trial that could prevent COVID-19 disease cases in just six months. This phase 4 vaccine study will include 1,800 participants and researchers from Harvard’s School of Public Health, the University of Texas MD Anderson Cancer Center in Houston, Cedars Sinai Medical Center in Los Angeles, and the Baylor College Medicine in Houston.

April 8, 2020: A non-peer-reviewed study found a significant difference in the CFR between the two countries. Our data further support the view that universal BCG vaccination has a protective effect on the course of COVID-19, probably preventing progression to severe disease and death.

April 7, 2020:  A phase 3 study is an Open-label, two-group, randomized controlled trial in up to 4,170 healthcare workers to determine if BCG vaccination reduces the incidence and severity of COVID-19 disease, the 2020 pandemic.

April 6, 2020 - Researchers on the Johns Hopkins Bloomberg College of Public Well discovered that the COVID-19 mortality fee amongst countries that use the Bacillus Calmette-Guérin (BCG) vaccination was eight instances lower than in these that don’t.

March 2020:  Countries with a national program of whole population BCG vaccination appear to have a lower incidence and death rate from COVID-19. This may be due to the known immunological benefits of BCG vaccination.

March 12, 2020:  Our results show that BCG and BCGΔBCG1419c protect T2D mice against TB via different participation of T and B lymphocytes, dendritic cells, and pro-inflammatory cytokines.

December 2019 - An observational study reported that the vaccine is related to fewer deaths from certain infections other than TB in low-income countries.

September 25, 2019:  This retrospective review was a 60-year follow-up of a clinical trial of the BCG vaccine that included 2963 participants vaccinated at a median age of 8 years.

May 2, 2019 - The discovery of innate immune memory has greatly improved our understanding of the mechanisms underlying the non-specific effects induced by BCG vaccination. However, a full understanding of the molecular mechanisms that underlie this phenomenon is still evolving. Numerous epidemiological, clinical, and immunological studies demonstrate that BCG vaccination impacts subsequent infections' immune response, resulting in reduced morbidity and mortality. Important lines of evidence indicating that BCG protects against viral pathogens come from experimental studies in mice showing that BCG offers protection against various DNA and RNA viruses, including herpes and influenza viruses. Recently, BCG's effect on an experimental viral infection in humans has been demonstrated. These effects are thought to be mediated via the induction of innate immune memory and heterologous lymphocyte activation, resulting in enhanced cytokine production, macrophage activity, T-cell responses, and antibody titers.

December 29, 2018:  In T1D, BCG vaccination restored blood sugars to near normal, even in patients with advanced disease of >20 years duration. This clinically important effect may be driven by the immune system's resetting and shifting glucose metabolism from overactive oxidative phosphorylation, a state of minimal sugar utilization, aerobic glycolysis, and high glucose utilization for energy production.

May 30, 2017:  Studies in mice have shown a beneficial effect of the BCG vaccine against allergic asthma, multiple sclerosis, and diabetes. However, understanding its mechanism is still fragmentary and requires further in-depth research. Some observational or intervention studies in humans have also suggested a beneficial effect, but definitive evidence for this requires confirmation in carefully conducted prospective studies.

September 1995 This CDC report updates and replaces previous recommendations regarding the use of Bacillus of Calmette and Guerin (BCG) vaccine for controlling tuberculosis (TB) in the United States (MMWR 1988;37:663-4, 669-75). 

1995 - Generation of nitric oxide and interferon-gamma clearance after BCG infection are impaired in mice that lack the interferon-gamma receptor.

1994 - Efficacy of BCG Vaccine in the Prevention of Tuberculosis: Meta-analysis of the Published Literature.

BCG Vaccine Clinical Trials

BCG is currently involved in 102 active and recruiting clinical trials covering various conditions. Click here to review the various ongoing clinical trials. Active BCG Clinical Trials Focused on Preventing SARS-CoV-2 Infections From Developing COVID-19 Disease include the following:

  • Clinical Trial NCT04327206: BCG Vaccination to Protect Healthcare Workers Against COVID-19 (BRACE) - last updated on October 22, 2020.
  • Clinical Trial NCT04328441: Reducing Health Care Workers Absenteeism in Covid-19 Pandemic Through BCG Vaccine (BCG-CORONA) - the last update on August 19, 2020.
  • Clinical Trial NCT04348370: BCG Vaccine for Health Care Workers as Defense Against COVID 19 (BADAS) - last update on May 27, 2020.