Re: The Bacillus Calmette-Guerin (BCG) Vaccine Is it a better choice for the treatment of viral warts? Sultan Qaboos University Med J, February 2021, Vol. 21, Iss. 1, pp. e141–142, Epub. 15 Mar 21 Submitted 11 Oct 20 Accepted 6 Nov 20 This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License. https://doi.org/10.18295/squmj.2021.21.01.023 LETTER TO THE EDITOR رد: لقاح ُعَصيَّة كامليت-غريان هل هو خيار أمثل لعالج الثآليل الفريوسية؟ Dear Editor, I read the distinguished study by Al-Yassen et al. published in the August 2020 issue of SQUMJ.1 This study compared the effectiveness of the intradermal bacillus Calmette-Guérin (BCG) vaccine with the topical salicylic acid (SA) in treating viral warts among a cohort of Iraqi patients. They found that BCG vaccine was more effective compared to topical SA in the treatment of viral warts with the best response observed in treating genital warts, followed by flat warts; plantar warts showed the least response to this therapy.1 They concluded that the BCG vaccine could be regarded as an alternative therapy with a simple and cheap implementation in the clinical field.1 The precise diagnosis of tuberculosis (TB) is an essential step in TB control and prevention program worldwide, particularly in the developing countries. In Iraq, TB is a worrying health problem. The available data indicates that Iraq is among seven of the countries of the Eastern Mediterranean Region with a high TB burden; Iraq accounts for 3% of the total number of cases.2 There are an estimated 20,000 TB cases in Iraq and the number of estimated deaths due to TB is more than 4,000 annually.2 Tuberculin skin test (TST) is applied widely to assess BCG vaccine efficacy and screen latent TB infection. Studies have demonstrated that TST interpretation is affected by the antecedent BCG vaccine exposure.3–5 I assume that implementing intradermal BCG vaccine immunotherapy in treating viral warts could ultimately curtail employing TST in the diagnostic panel of TB in suspected patients. Hence, weighing the benefit-risk ratio of this new treatment modality must be exercised before finally recommending it in the clinical setting in high TB burden countries, including Iraq. Conducting additional clinical and immunological studies on that aspect is imperative. Mahmood D. Al-Mendalawi Department of Paediatrics, Al-Kindy College of Medicine, University of Baghdad, Baghdad, Iraq E-mail: mdalmendalawi@yahoo.com References 1. Al-Yassen AQ, Al-Maliki SK, Al-Asadi JN. The bacillus Calmette-Guérin (BCG) vaccine: Is it a better choice for the treatment of viral warts? Sultan Qaboos Univ Med J 2020; 20:e330–6. https://doi.org/10.18295/squmj.2020.20.03.013. 2. World Health Organization. Iraq. From: http://www.emro.who.int/irq/programmes/tuberculosis.html Accessed: Oct 2020. 3. Yildirim C, Küçük AI, Ongüt G, Oğünç D, Colak D, Mutlu G. [Evaluation of tuberculin reactivity in different age groups with and without BCG vaccination]. Mikrobiyol Bul 2009; 43:27–35. 4. Subramani R, Datta M, Swaminathan S. Does effect of BCG vaccine decrease with time since vaccination and increase tuberculin skin test reaction? Indian J Tuberc 2015; 62:226–9. https://doi.org/10.1016/j.ijtb.2015.08.002. 5. Mancuso JD, Mody RM, Olsen CH, Harrison LH, Santosham M, Aronson NE. The long-term effect of bacille Calmette-Guérin vaccination on tuberculin skin testing: A 55-year follow-up study. Chest 2017; 152:282–94. https://doi.org/10.1016/j.chest.2017.01.001. Response from the Authors Dear Reader, After reading the above Letter to the Editor, we would like to clarify some points. First, many studies previously done in countries such as India (where over 2.4 million TB patients were reported in 2019 with an incidence rate https://creativecommons.org/licenses/by-nd/4.0/ https://doi.org/10.18295/squmj.2020.20.03.013 https://doi.org/10.1016/j.ijtb.2015.08.002 https://doi.org/10.1016/j.chest.2017.01.001 Re: The Bacillus Calmette-Guerin (BCG) Vaccine Is it a better choice for the treatment of viral warts? e142 | SQU Medical Journal, February 2021, Volume 21, Issue 1 of 19.9/100,000) recommend and support the efficacy and safety of BCG in treatment of viral warts.1,2 Second, the World Health Organization report referenced above was released in 2014.3 Recent data about the extent of TB in Iraq according to the annual report of the Iraqi Ministry of Health in 2019, states that the number of new cases registered in Iraq was 6,663 with an incidence rate of 17/100,000.4 Third, traditionally, the tuberculin TST has been used as the standard for the identification of prior exposure to Mycobacterium tuberculosis. However, the specificity of a positive test is less than optimal.5 Four, it was reported that in subjects without active TB, immunisation with BCG increases the possibility of a positive tuberculin skin test, but the effect of BCG on the Mantoux test was less after 10–15 years of vaccination.6,7 In addition, BCG vaccination was not an important cause of false-positive Mantoux test results, except in populations with a low prevalence of active TB.8 Finally, there is evidence suggesting that BCG revaccination in adolescence confers protection against TB meningitis.9 In the United Kingdom, boosting healthy previously vaccinated adults was found to be well tolerated and improved purified protein derivative-specific cluster of differentiation 4+ T-cell responses.10 Despite the importance of what has been mentioned above and irrespective of the extent of TB in Iraq or elsewhere, TB is an important health problem and the benefit/risk of the BCG vaccine should be evaluated before its use. Moreover, the interpretation of the skin test needs to take into consideration the individual clinical context and evaluation of other risk factors for infection. A cut-off measurement of skin indurations of >15 mm is more likely to be the result of TB infection rather than previous BCG vaccination.8 Asaad Q. Al Yassen, Shukrya K. Al Maliki, *Jasim N. Al Asadi Department of Family & Community Medicine, College of Medicine, University of Basrah, Basrah, Iraq *Corresponding Author’s e-mails: jnk5511@yahoo.com and jasim.naeem@gmail.com References 1. Central TB Division, Ministry of Health and Family Welfare. India TB report 2020. From: https://tbcindia.gov.in/showfile.php?lid=3538 Accessed: Oct 2020. 2. Jaisinghani AK, Dey VK, Suresh MS, Saxena A. Bacillus Calmette-Guerin immunotherapy for recurrent multiple warts: An open-label uncontrolled study. Indian J Dermatol. 2019; 64:164. https://doi.org/10.4103/ijd.IJD_558_16. 3. World Health Organization. Iraq. From: http://www.emro.who.int/irq/programmes/tuberculosis.html Accessed: Oct 2020. 4. Ministry of Health/Environment, Republic of Iraq. Annual Statistical Report, 2019. From: https://moh.gov.iq/upload/upfile/ar/1349.pdf Accessed: Oct 2020. 5. Regatieri A, Abdelwahed Y, Perez MT, Bush LM. Testing for tuberculosis: The roles of tuberculin skin tests and Interferon gamma release assays. Lab Med 2011; 42:11–16. https://doi.org/10.1309/LMU57KYINZ6WJTIT. 6. Farhat M, Greenaway C, Pai M, Menzies D. False-positive tuberculin skin tests: What is the absolute effect of BCG and non-tuberculous mycobacteria? Int J Tuberc Lung Dis 2006; 10:1192–204. 7. Wang L, Turner MO, Elwood RK, Schulzer M, FitzGerald JM. A meta-analysis of the effect of Bacille Calmette Guérin vaccination on tuberculin skin test measurements. Thorax 2002; 57:804–9. https://doi.org/10.1136/thorax.57.9.804. 8. Araujo Z, de Waard JH, de Larrea CF, Borges R, Convit J. The effect of Bacille Calmette-Guérin vaccine on tuberculin reactivity in indigenous children from communities with high prevalence of tuberculosis. Vaccine 2008; 26:5575–81. https://doi.org/10.1016/j.vaccine.2008.08.006. 9. Rodrigues LC, Diwan VK, Wheeler JG. Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: A meta-analysis. Int J Epidemiol 1993; 22:1154–8. https://doi.org/10.1093/ije/22.6.1154. 10. Whelan KT, Pathan AA, Sander CR, Fletcher HA, Poulton I, Alder NC, et al. Safety and immunogenicity of boosting BCG vaccinated subjects with BCG: Comparison with boosting with a new TB vaccine, MVA85A. PLoS One 2009; 4:e5934. https://doi.org/10.1371/journal. pone.0005934. https://doi.org/10.4103/ijd.IJD_558_16 https://doi.org/10.1309/LMU57KYINZ6WJTIT https://doi.org/10.1136/thorax.57.9.804 https://doi.org/10.1016/j.vaccine.2008.08.006 https://doi.org/10.1093/ije/22.6.1154 https://doi.org/10.1371/journal.pone.0005934 https://doi.org/10.1371/journal.pone.0005934