Table 1: Lily's dataTotalAntibiotic resistance (R) / sensitivity (S)PyrazinamidenumberIsoniazidRifampinEthambutolKanamycinМоxiПlохасinCapreomycinofpatientisolatesInhibitsInhibitsInhibits cellInterferes withInhibitsInhibits DNAMechanism ofDNAmetabolismreplicationproteinsynthesiscell wallwallactionformation replicationformationunclearGroup A (n = 32)9RRRSS3RSRSSR3RSSS4RRSRSSRRRSSSS2RRRS1RSSSSS2RRS1RRSRRR1RRSGroup B (n = 30)3RRS2RSSRSS1RSRSRSS1RSSSRSS7RSSS3SRSRSSS1RSSSS2SSRSSS1SSRSSa Tested and defined using standard protocols9SSSSPractice Question #10 p. 225A. M.tuberculosis (Mtb) takes about 12h to 18h to do a cell division. This partially explainswhy it takes so long to grow the bacteria for diagnosis (4-6 weeks). How can this impacttreatment? Be precise.B. Which group of patients will be the most challenging to treat? Explain why you chosethat group? Be precise. Practice Case study p. 224 part: Tuberculosis (TB) in indigenous populations.Lily was a recent science graduate of the University of Alberta and was 11 months into her 12 -month Master of Science in Global Health degree, at Dalhousie University. This relatively newprogram was created to provide the multidisciplinary training required of scientists working tomeet the complex challenges of global public health issues. The University had partnered with theNational Collaborating Centre for Indigenous Health (NCCIH) and that was why Lily now foundherself doing her Global Health Field Practicum in the Northern Territories, working on a studyof drug resistant TB infections among Innuit communities.The different communities included in her research were close to 7000 individuals, with multiplediagnosed cases of TB. And while she was grateful that drug-resistant TB in Canada remainedbelow the global average (Public Health Agency of Canada, 2019), she was cognizant of thepossibility that this might not always be the case for Indigenous peoples. In addition, much to ournational shame, she knew that the rate of TB among Canadian born Indigenous Peoples was higherthan that of Canadian born non-Indigenous people; those worst affected were the Inuitcommunities, at a shocking 300x higher rate of infection. In fact, incidence rates for 2016 were asfollows:0.6 per 100,000 among Canadian-born, non-Indigenous people.per 100,000 among all First Nations people.170.1 per 100,000 among Inuit.2.1 per 100,000 among Métis people.It had been hypothesized that drug resistance was one of the reasons for the increased incidenceand mortality rates and the failure of the standard DOT strategy (Directly Observed Treatment),part of the World Health Organization's (WHO) strategy for global eradication of TB. That'swhere Lily came in: the existence and extent of multi-drug resistant (MDR) TB had not beendocumented. So, her project was to do just that.Lily was studying two groups of TB patients – one group (group A) included 32 patients whowere not responding to DOTS. Her control (group B) consisted of 30 patients who werepresumptively diagnosed with TB based on symptoms and a positive sputum smear using acid-faststaining. Group B had just started treatment.Her experimental strategy was quite simple – isolate Mycobacterium tuberculosis from patientsputum samples and determine the resistance of the isolated strains to rifampicin, isoniazid,pyrazinamide, and ethambutol, as well as the antibiotics kanamycin, moxifloxacin andcapreomycin. Because of how the organism was spread, she followed the standard operatingprocedure for working with this pathogen and with the patients. Now, finally, after waiting weeksfor the cultures to grow, she had TB isolates from each patient and had just finished recording theresults of the sensitivity testing (Table 1).The results were frightening. (Note: these results are fictional, 90% of cases of TB in Canada areAbx sensitive, no increase in Abx resistance has been seen so far).

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The causative agent of this infection is a bacteria widely known as Mycobacterium tuberculosis, and…