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The BCG Vaccine protects against COVID-19

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Ecological studies have suggested fewer COVID-19 morbidities and mortalities in Bacillus Calmette–Guérin (BCG)-vaccinated countries than BCG-non-vaccinated countries. However, these studies obtained data during the early phase of the pandemic and did not adjust for potential confounders, including PCR-test numbers per population (PCR-tests).1

In the absence of specific therapy, researchers have been exploring potential preventive and therapeutic options. There was a huge  buzz about the protective effect of Bacille Calmette-Guérin (BCG) vaccine in COVID-19. Based on epidemiological correlations, many unpublished preprints hypothesized that the BCG vaccine may offer protection against COVID-19. It gained so much popularity that within 20 days three randomized controlled trials (RCTs) got registered, and many more are in the pipeline.2 However, to make an informed decision, it is critical to understand the mechanism of action of BCG, and appraise the robustness of the evidence.

The basis of the possible use of the BCG vaccine against COVID-19 lies in its non-specific effects (NSEs) over the immune system.3 The NSEs of BCG are mainly mediated by potentiating innate immune response through epigenetic mechanisms, which act as de novo enhancers to boost the immune response against a secondary challenge.3-5 This enhancing response is popularly known as ‘trained immunity’ and is very characteristic of BCG. This trained immunity also offers protection against a variety of pathogens (Salmonella, Shigella, malaria, respiratory viruses, etc.) other than Mycobacterium tuberculosis, and forms the basis of its use in bladder cancer, melanoma etc.

However, in terms of COVID-19 context, the relationship between BCG and COVID-19 is being proven by looking at correlation/ association among two data set (BCG vaccine coverage and COVID-19), without acknowledging the variables like the difference in testing strategies, reporting bias, demographics, nation’s ability to respond to the pandemic, prevalence of co-morbidities, and different stages of the pandemic across various countries might have a significant impact on these associations/correlations and must be interpreted carefully. Therefore, at this stage, this association should be considered as a hypothesis only and should be tested through appropriately designed studies. Though the epidemiological association between BCG and COVID-19 is striking, it does not prove causal relationship unless tested in well-designed clinical trials.

Also, it should be noted that the NSEs of the BCG vaccine have not been well-studied in human beings and their clinical relevance is unknown.2,3

A December 2020 study6 also states that besides unproven efficacy of the BCG vaccine, believing such reports and going for revaccination with BCG can put at serious risk patients with primary or secondary immunodeficiency. The report further states that even if the BCG vaccine is effective in preventing COVID-19 deaths or reducing its severity, the effect of this vaccine and its relevance is yet to be proven. Furthermore, It is very difficult to compare the epidemiologic data about COVID-19 in different countries. There are countless factors, mainly social and related to the healthcare system, which can be more decisive than the hypothesis of trained immunity induced by BCG. Until now, we can say that BCG’s protective role is, at least, insufficient, given many other factors that corroborate SARS-CoV-2 infection and/or its severity.

Therefore, in the absence of evidence, the BCG vaccination for the prevention of COVID-19 cannot be recommended. Despite the fact that greater BCG vaccine coverage may reduce the risk of deaths due to COVID-19, this needs to be further studied by observational studies and confirmed by randomized clinical trials.

Source:

1 Urashima M, Otani K, Hasegawa Y and Akutsu T. BCG Vaccination and Mortality of COVID-19 across 173 Countries: An Ecological Study. Int J Environ Res Public Health. 2020;17(15):5589.
2 World Health Organization. Bacille Calmette-Guérin (BCG) vaccination and COVID-19. Available from: https:/ /www.who.int/news-room/commentaries/detail/ bacillecalmette-guérin-(bcg)-vaccination-and-covid-19.
3 SAGE Working Group on BCG Vaccines and WHO Secretariat. Report on BCG vaccine use for protection against mycobacterial infections including tuberculosis, leprosy, and other nontuberculous mycobacteria (NTM) infections. World Health Organization; 2017. Available from: https://www.who.int/immunization/sage/ meetings/ 2017/october/1_BCG_report_revised_version_online.pdf. Accessed April 14, 2020.
4 Moorlag SJCFM, Arts RJW, van Crevel R, Netea MG. Non-specific effects of BCG vaccine on viral infections. Clin Microbiol Infect. 2019;25:1473-8.
5 Arts RJW, Moorlag SJCFM, Novakovic B, et al. BCG vaccination protects againstexperimental viral infection in humans through the induction of cytokines associated with trained immunity. Cell Host Microbe. 2018;23:89-100.e5.
6 Sarinho E, Goudouris E, Solé D. BCG vaccine: Worrying proposal for COVID-19. Vaccine. 2020;S0264-410X(20)31593-0. doi: 10.1016/j.vaccine.2020.12.026.

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Coronavirus

Dos and don’ts for vacay activities

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It is not a one size fits all when it comes to vacations or holidays because every family has a different demographic – some may have small kids who need to be taken to a washroom very often, some may have elderly who cannot sit too long during road trips. Therefore, every family should decide based on their own family size, needs and facilities. Traveling will inevitably lead to exposures to unvaccinated kids and adults. But the risk will be decided based on the extent of that exposure.

Masks reduce transmission and have been proven to be an effective tool with vaccination. Wearing a mask indoors and in public spaces further cuts down on risk considerably.

Before you travel:

  1. Get your RTPCR test done

While traveling:

  1. Wear a mask covering your nose and mouth at all times when you are in public places or around individuals that cannot maintain a safe distance of 6 feet away from you.
  2. Avoid crowds and stay at least 6 feet/2 meters from anyone who you do not know personally with their health history.
  3. Wash your hands often or use hand sanitizer (with at least 60% alcohol).

When you return from your vacation:

  1. If you see any signs of COVID, get tested and isolate yourself from other family members as well.
  2. Even if you test negative, stay home and self-quarantine for the full 7 days.
  3. If you don’t get tested, stay home and self-quarantine for 10 days after travel.
  4. Self-monitor for COVID-19 symptoms; isolate and get tested if you develop symptoms.

UIN: 407HP17G

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It hasn’t affected kids till now – it won’t affect them ever

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Schools reopening across the globe has brought about a sense of panic in some parents and a sense of confidence in others because vaccination for children is yet to come and unvaccinated children are both at direct risk for COVID as well as at risk of transmitting the virus to others.

According to the World Health Organisation (WHO), data suggests that children under the age of 18 years represent about 8.5% of reported cases, with relatively few deaths compared to other age groups and usually mild disease. However, cases of critical illness have been reported. As with adults, pre-existing medical conditions have been suggested as a risk factor for severe disease and intensive care admission in children. Further studies are underway to assess the risk of infection in children and to better understand transmission in this age group.

Although research has shown that children develop severe disease from COVID-19 far less commonly than adults, and therefore, the risk of death due to severity of COVID-19 is also much lower in children. However, they are not immune. There are reports of children dying due to COVID-19.  But even when children do not get seriously ill with COVID-19 or show symptoms, they can still transmit the virus to other children and adults. The rate of child-to-adult transmission of SARS-CoV-2 is roughly half the rate of adult-to-child transmission. So even when the risk is low for children, transmission to other unvaccinated kids and adults is still a serious concern.

UIN:406HP105F

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Coronavirus

Vaccination can help us tide over the third wave

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The  second wave is declining, although up to 30-40,000 daily new cases continue to be recorded. India is far from being a COVID-19 free nation. Moreover, the looming third wave and alerts released by different State heads to be prepared for a third wave or to make adequate arrangements for the third wave in terms of oxygen cylinders, beds, critical care wards, etc. has kept us all on our toes and inside homes for fear of expediting the arrival of the third wave.

Eminent virologist and retired professor (CMC Vellore), Dr. T Jacob John, in a recent media interview said if the Government can do justice to the vaccination, in terms of making it available in abundance and everywhere, even the unlikely probability of a third wave can be mitigated, adding that in other words, the third wave can be and must be prevented with vaccination. Dr. John also believes that the two strong waves of COVID-19 pandemic in India would have created high herd-immunity, which is why even a moderate level of vaccination will surely avert the third wave.

We should continue to follow physical distancing protocols and avoid crowding indoors or outdoors as much as possible.

UIN: 344HP186R

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Complete vaccinated individuals three times less likely to get COVID-19

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In what comes as more evidence to back completing the (two-dose or one-dose) mandated course for vaccinations for COVID-19, a recent update published by the Imperial College London has shown that people who have received both doses of their coronavirus vaccine are three times less likely to get infected with COVID-19. These results from the 13th round of the Imperial-led REACT-1 study, a major coronavirus monitoring programme, are based on swab tests taken by almost 100,000 people in England between 24 June and 12 July. 

According to their website, REACT (REal-time Assessment of Community Transmission) is a series of studies that are using home testing to improve the understanding of how the COVID-19 pandemic is progressing across England. This major research programme was commissioned by the Department of Health and Social Care (DHSC) and is being carried out by Imperial College London in partnership with Ipsos MORI and Imperial College Healthcare NHS Trust.

The analysis by Imperial College London and Ipsos MORI, which had almost 100,000 volunteers taking part in the study in England between June 24 and July 12, suggests that double vaccinated people are also less likely to pass on the virus to others. Results have also indicated that people who were fully vaccinated were less likely to be carriers of infection to pass the virus on to others, because they have a lower viral load on average and therefore shed less virus. 

In his statement to the Press post release of study results, the UK Vaccines Minister Mr. Nadhim Zahawi also stated, “these results show the positive impact of the vaccination program with those who are double jabbed three times less likely than unvaccinated people to get the virus and less likely to pass on this awful disease to those around them”.

It is important to note that no vaccine has 100% efficacy but benefits outweigh the risks and therefore vaccination is an important step towards curbing the pandemic. Vaccination however, must also be complemented by COVID appropriate behavior.

UIN 387HP217R

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Coronavirus

Breastfeeding post vaccination can kill your baby

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There isn’t any research to support this claim, and based on how vaccines work, there is no reason to believe that the vaccine could harm mom or baby. In fact studies support the fact that the vaccines are not excreted into the breast milk, but antibodies produced by mothers in response to the COVID-19 vaccine do — providing hope that breastfed babies might have some level of protection.

A report published in the journal Nature states that COVID-19 vaccines do not carry a risk of igniting an active infection and that they are extremely unlikely to cross into breast milk. The report further elaborates how the fragile messenger RNA used in the Pfizer–BioNTech and Moderna vaccines, is designed to break down so quickly that it should never leave the cells where it was injected. Therefore, it cannot get into the bloodstream and then the breast. In fact, experts believe none of the current vaccines will be excreted into breast milk.

The World Health Organisation (WHO) Strategic Advisory Group of Experts on Immunization (SAGE) Guidance also recommends that mothers continue to breastfeed after vaccination. The Centre for Disease Control (CDC) and the UK Joint Committee on Vaccination and Immunisation issued statements shortly after the first vaccines were authorized in both countries recommending COVID-19 vaccination for breastfeeding women.

Australia’s Department of Health has indicated that breastfeeding women can get an approved COVID-19 vaccine and don’t need to stop breastfeeding before or after. 

Therefore, in conclusion, no safety concerns have been identified in lactating women who have been vaccinated. Women can continue to breastfeed pre and post COVID-19 vaccination.

 UIN: 400HP104F

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