BACKGROUND: Zambia is one of the TB high-burden countries. It is important to track the progress being made towards enhancing case finding and reducing mortality. We reviewed routine TB notifications and mortality trends, over a decade from all facilities in Zambia.
METHODS: A 10-year retrospective study of TB notifications and mortality trends was performed using a Joint Point Analysis version 4.9.0.0, NCI. We extracted the annual national TB program data for the period under review.
RESULTS: There was a decline in annual point average for notification between 2010 and 2020 in both males and females, but the females notification rates had a higher rate of decline (AAPC = -6.7, 95%CI:-8.3 to -5.0), p<0.001) compared to the decline in males notification rate (AAPC = -4.1, 95%CI:-4.1 to -5.1, P<0.001). We found a significant growth rate in the proportion of TB patients that were bacteriologically confirmed (AAPC = 6.1, 95% CI: 3.6 to 8.7, p< 0.001), while the proportion of clinically diagnosed patients declined (AAPC= -0.1, 95%CI: -2.3 to 2.1, p<0.001). Notification of drug-resistant TB increased exponentially (AAPC=27.3, 95% CI: 13 to 41), p< 0.001) while mortality rate declined from 21.3 in 2011 to 12.7 in 2019 per 100,000 population (AAP=-5.6, 95%CI: -9.6 to -1.5, p=0.008).
CONCLUSIONS: This study has illustrated the importance of reviewing and analyzing routinely collected TB data by national programs. The study revealed areas of improvement in terms of TB control and underscores the need for increased and sustained investment in case detection and diagnostics.

To explore tuberculosis (TB) incidence in Canada and the United States from 1953 to 2015. In the most recent decade, the US incidence was lower than that of Canada. Since both countries are high income and have low TB incidence with similar TB surveillance programs, we hypothesized that rates should be similar.
TB incidence data from 1953 to 2015 were retrieved for both countries. Joinpoint regression was performed to identify change points in the trend, and direct standardization of US rates using Canadian ethnic population distribution was calculated. Adjusted rate and average annual percent change (AAPC) were estimated.
Canada rates/100,000 were higher from 1953 to 1974 and similar from 1975 to 1985. This coincided with a change in US case definition in 1975. US rates were higher from 1986 to 1996. HIV/TB coinfection in the USA was 10.2% compared to that of Canada, 1.6%. Rates were similar from 1997 to 2004. Canada rates were again higher from 2005 to 2015. The Canada average AAPC rate in 1975-2015 was lower, - 2.9%, compared to that of the USA, - 4.1%. Foreign-born and Indigenous population proportions were 20.2% and 4.2% for Canada and 12.9% and 1.7% for the USA. The US rate adjusted to the Canada ethnic composition was 4.8 compared to the Canadian rate of 4.7.
Case definition change and HIV coinfection contributed to the 1980 US rate increase. TB rates decreased in both countries from 1997, but more rapidly in the USA. The Canada proportion of foreign-born and Indigenous populations was higher. When US rates were standardized by Canada ethnic distribution, the national rates were similar. Further exploration of factors contributing to differences between these countries is needed.