A tale of two pandemics
Dr Anjana Roy from Public Health England has written the following article:
A pandemic is defined as a disease that spreads across whole countries or the world. Tuberculosis and COVID-19 are both pandemics that show ongoing, sustained community transmission across continents (1).
Similarities between the 2 pandemics:
Cause major infection - related morbidity and mortality around the world. In 2018 causing 1.2 million deaths in 2018 (2), while COVID-19 has infected over 10 million and caused 502,278 deaths (as of 30/06/20) (3).
Present respiratory symptoms: fever, cough and dyspnoea (4), among other symptoms.
People with co-morbidities are at increased risk of severe disease and adverse outcomes in both diseases
Considerable social impact – including stigma, discrimination, and isolation
Economic impact and catastrophic costs to individuals and households
Differences between the 2 pandemics
TB is a slow pandemic that has been with human kind for a millennia and the corona virus which causes COVID-19 (SARS-CoV-2) is new and spreading rapidly around the world.
Children are less severely affected by COVID-19, while 1.1 million children had TB in 2018, out of whom 200,000 died.
Majority of the TB cases and deaths occur in low and middle-income countries while high income countries have low rates. With COVID – 19(2) Europe became the second epicentre after China, thereby enabling the mobilisation of more global resources and person power in a year than Tuberculosis has in decades (1).
What we don’t know yet?
The clinical and epidemiological interaction between Tuberculosis and COVID -19 is complex and still to be fully understood. It is likely that Tuberculosis transmission might rise because of increased respiratory symptoms associated with COVID-19, or may decrease due to COVID related self-isolation and quarantine.
Extreme pressures on health systems, exacerbated by COVID-19, mean that people with Tuberculosis are likely to face decreased access to diagnostic and treatment services, resulting in adverse outcomes.
Comparison of mortality
A recent study (5) described for the first time a group of patients who died with TB (active disease or sequelae) and COVID-19 in the discrete cohorts of A and B. Data of both cohorts were combined to assess the mortality. Cohort A included 49 patients with TB and COVID-19 from 26 centres in Belgium, Brazil, France, Italy, Russia, Singapore, Spain, and Switzerland, (6) whereas cohort B included 20 cases admitted to a single reference hospital located in Northern Italy.
The study findings show that:
a. mortality is likely to occur in elderly patients with co-morbidities;
b. TB might not be a major determinant of mortality and
c. migrants had lower mortality, probably because of their younger age and lower number of co-morbidities. However, in settings where advanced forms of TB frequently occur and are caused by drug-resistant strains of M. tuberculosis, higher mortality rates can be expected in young individuals, a finding which would be applicable to the prison population.
Impact of association of the pandemics
Irrespective of the probable temporal association between COVID-19 and TB, both the infectious diseases may have synergistic impact on social and economic impact worldwide (7). Association between COVID-19 remains unclear - with increasing data we will be able to get a better understanding of the differential effect of COVID 19 according to socio-economic position. It is thought that COVID -19, like tuberculosis will be associated with medical poverty trap, in which poorer people have a higher likelihood of infection, disease and adverse outcomes 1. Again these findings are particularly pertinent to the prison population.
Tuberculosis remains a global health emergency and needs our attention more than ever, given that significant resources are now being diverted to COVID-19 management (8) To lose sight of the unfinished business of tuberculosis control will jeopardise important milestones, gains and ambitions, and we believe that now more than ever is the time to care about TB. The two pandemics remind us of the need to be proactive and long sighted, to plan and not to be complacent (1).
1). Wingfield T, Cuevas LE, MacPherson P, Millington KA, Squire SB Tackling two pandemics: a plea on World Tuberculosis Day..Lancet Respir Med. 2020 Jun
2). WHO Global tuberculosis report. 2019. https://www.who.int/tb/global-report-2019/
3). WHO Dashboard for COVID. Accessed on 30th June 2020 https://covid19.who.int/
4). Khurana AK, Aggarwal D. The (in)significance of TB and COVID-19 co-infection. Eur Respir J. 2020 Jun 18
5). Motta I, Centis R, D’Ambrosio L, García-García JM, Goletti D, Gualano G, Lipani F, Palmieri F, Sánchez-Montalvá A, Pontali E, Sotgiu G, Spanevello A, Stochino C, Tabernero E, Tadolini M, van den Boom M, Villa S, Visca D, Migliori GB. Tuberculosis, COVID-19 and migrants: preliminary analysis of deaths occurring in 69 patients from two cohorts. Pulmonology. 2020 May 14.
6). Tadolini M, Codecasa LR, García-García JM, Blanc FX, Borisov S, Alffenaar JW, Andréjak C, et al. Active tuberculosis, sequelae and COVID-19 co-infection: first cohort of 49 cases. Eur Respir J. 2020 May
7). Khurana AK, Aggarwal D. The (in)significance of TB and COVID-19 co-infection. Eur Respir J. 2020 Jun 18:2002105.
8). Togun T, Kampmann B, Stoker NG, Lipman M.Version 2. Anticipating the Impact of the COVID-19 Pandemic on TB Patients and TB Control Programmes Ann Clin Microbiol Antimicrob. 2020 May 23;19(1):21
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