key: cord-0734017-ngj3t3te
authors: Geric, Coralie; Saroufim, Mariane; Landsman, David; Richard, Jonathan; Benedetti, Andrea; Batt, Jane; Brode, Sarah K; Ahmad Khan, Faiz
title: Impact of Covid-19 on Tuberculosis Prevention and Treatment in Canada: a multicentre analysis of 10,833 patients
date: 2021-12-17
journal: J Infect Dis
DOI: 10.1093/infdis/jiab608
sha: 3bd59b6f9a0320fedb302188f2a6b3d578f17d69
doc_id: 734017
cord_uid: ngj3t3te

We assessed the Covid-19 pandemic’s impact on treatment of latent tuberculosis, and of active tuberculosis, at three centres in Montreal and Toronto, using data from 10,833 patients (8685 with latent tuberculosis infection, 2148 with active tuberculosis). Observation periods prior to declarations of Covid-19 public health emergencies ranged from 219 to 744 weeks, and post-declarations, from 28 to 33 weeks. In the latter period, reductions in latent tuberculosis infection treatment initiation rates ranged from 30% to 66%. At two centres, active tuberculosis treatment rates fell by 16% and 29%. In Canada, cornerstone measures for tuberculosis elimination weakened during the Covid-19 pandemic.

M a n u s c r i p t 1 Background 1 Tuberculosis (TB) preventive therapy, along with prompt diagnosis and treatment of 2 active TB, are cornerstones of TB control. In Canada, most TB prevention and care 3 occurs in outpatient settings. Thus, we sought to determine if reductions in non-urgent 4 clinical activities mandated in response to the Covid-19 pandemic resulted in fewer 5 individuals initiating treatment for latent TB infection (LTBI) or active TB, in Canada's 6 two most populous cities: Montreal and Toronto. Data from high TB burden, low and 7 middle-income countries demonstrate an impact on various aspects of TB care in a 8 variety of settings [1] . By contrast, few data have been published, on the impact of 9 Covid-19 on LTBI treatment -a fundamental aspect of the World Health Organization's 10 Global End TB Strategy in low TB incidence countries [2] . Such data are of value for 11 understanding how Covid-19 mitigation policies might affect TB elimination efforts in low 12 TB incidence countries. 13 Canada is a low TB burden country, with a national TB incidence of 4.8 per 100,000 in 14 2017 [3] . However, TB incidence in certain Canadian subpopulations is considerably 15 higher than the national average. In 2017, Montreal and Toronto saw TB rates of 6.0 16 and 9.8 per 100,000, respectively [4, 5] .

The cities of Montreal (in the province of Quebec) and Toronto (Ontario) pre-Covid eras demonstrated significant reductions ranging from 30% at the MCI to 62 66% at SMH. Figure 1 shows the average number of weekly LTBI registrations in each 63 year.

A total of 2148 patients initiated treatment for active TB: 869 at the MCI, 927 at TWH, 65 and 352 at SMH. The adjusted rate ratio for per week for active TB treatment initiation 66 was lower in the Covid era by 16% at the MCI and by 29% at TWH. At SMH, the M a n u s c r i p t 4 adjusted rate ratio showed a 2% higher rate of active TB treatment initiation during the 68 Covid era. The observed differences in active TB treatment initiation rates between We did three sensitivity analyses. First, for both LTBI and active TB, we fit an M a n u s c r i p t 5 The third sensitivity analysis restricted the analysis for latent TB infection to individuals 90 who were at high risk of re-activation: close contacts or immunosuppressed individuals.

The observed associations were similar as in our primary analyses for the two sites programmatic data [13, 14] , and while observations were consistent with ours, the 125 analyses were limited to descriptive statistics, and only one study had data on LTBI [13] . 126 Our study thus provides an important contribution to the current literature, through the 127 use of registry data, adjusted analyses, and granular information for the impacts on A c c e p t e d M a n u s c r i p t M a n u s c r i p t M a n u s c r i p t A c c e p t e d M a n u s c r i p t 

The impact of COVID-19 on TB: a review of the data

World Health Organization. The End TB Strategy. Global strategy and targets for tuberculosis prevention

Ontario Agency for Health Protection and Promotion (Public Health Ontario)

Ministère de la Santé et des Services sociaux. Portrait épidémiologique de la tuberculose au Québec

Coronavirus disease (COVID-19): Epidemiology update

Ontario Agency for Health Protection and Promotion (Public Health Ontario)

All Ontario: Case numbers and spread

Données COVID-19 par région sociosanitaire

R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing

Geneva: World Health Organization, 2020. 12. Civil society-led TB/COVID-19 Working Group. The impact of COVID-19 on the TB epidemic: A community perspective

Worldwide Effects of Coronavirus Disease Pandemic on Tuberculosis Services

A decrease in tuberculosis evaluations and diagnoses during the COVID-19 pandemic

A c c e p t e d M a n u s c r i p t