3.1 Case notifications

Data on the number of people diagnosed with tuberculosis (TB), based on standard case definitions and associated guidance on the recording and reporting of data provided by WHO, have been systematically collected at national level and then reported to WHO on an annual basis since the mid-1990s. Globally in 2021, 6.4 million people with a new episode of TB (new and relapse cases) were diagnosed and notified (Table 3.1.1). Of these, 83% had pulmonary TB. Collectively, the African, South-East Asia and Western Pacific Regions accounted for almost 90% of total notifications, with close to half in the South-East Asia Region alone.

Table 3.1.1 Notifications of TB, HIV-positive TB, MDR/RR-TB and XDR-TB cases, globally and for WHO regions, 2021

WHO region	Total notified	New and relapse^a	Pulmonary new and relapse number	Pulmonary new and relapse bacteriologically confirmed (%)	Extrapulmonary new and relapse (%)	HIV-positive new and relapse	MDR/RR-TB only^b	pre-XDR-TB or XDR-TB^c
African Region	1 508 787	1 479 535	1 281 737	66%	13%	265 224	18 887	1 079
Region of the Americas	227 592	213 212	183 202	79%	14%	18 331	4 530	268
South-East Asia Region	3 139 006	2 966 970	2 345 691	65%	21%	51 989	60 541	11 733
European Region	188 905	157 874	132 091	69%	16%	20 003	25 769	10 550
Eastern Mediterranean Region	503 760	497 895	383 193	57%	23%	1 759	3 882	1 024
Western Pacific Region	1 128 312	1 108 034	1 018 904	56%	8%	11 335	28 344	384
Global	6 696 362	6 423 520	5 344 818	63%	17%	368 641	141 953	25 038

^a New and relapse includes cases for which the treatment history is unknown. It excludes cases that have been re-registered as treatment after failure, as treatment after lost to follow up or as other previously treated (whose outcome after the most recent course of treatment is unknown or undocumented).
^b TB that is resistant to rifampicin, excluding any cases with known resistance to any fluroquinolone.
^c Pre-XDR-TB is TB that is resistant to rifampicin and to any fluoroquinolone. XDR-TB is TB that is resistant to rifampicin and to any fluoroquinolone and to at least one of bedaquiline or linezolid.

The big drop in the total number of people newly diagnosed and officially reported with TB in 2020 compared with 2019, from 7.1 to 5.8 million (-18%), was one of the main findings of the Global Tuberculosis Report 2021. The increase to 6.4 million in 2021 (Fig. 3.1.1) suggests a partial recovery in TB detection, following the major disruptions to provision of essential TB services caused by the COVID-19 pandemic. However, notifications in 2021 were still 10% below the level of 2019 and there are wide gaps between the estimated number of people who develop TB each year (incident cases) and the number detected and reported, reflecting a mixture of underreporting of detected cases and underdiagnosis. Gaps between notifications and estimates of TB incidence, especially in the 10 countries that account for most of the global gap, are discussed further in Section 3.3.

The global trend of a big decrease in the number of people newly diagnosed with TB in 2020 and a partial recovery in 2021 has been driven by trends in the South-East Asia Region. A similar pattern is evident in the Eastern Mediterranean Region and the Region of the Americas; in contrast, there was no recovery in the Western Pacific Region in 2021. The African Region stands out as having only a small reduction in TB notifications in 2020 followed by an increase in 2021.

Fig. 3.1.1 Notifications of TB cases (new and relapse cases, all forms) (black) compared with estimated TB incident cases (green), 2000–2021, globally and for WHO regions

The shaded area represents the 95% uncertainty interval.

In the 30 high TB burden countries, trends in notifications vary considerably (Fig. 3.1.2). In 2020, the first full year of the COVID-19 pandemic, there were particularly large absolute and relative reductions in India, Indonesia and Philippines, followed by some recovery in 2021. Countries such as Bangladesh and Pakistan experienced large reductions in 2020 but recovered to above 2019 levels in 2021. In some other Asian countries, such as Thailand and Viet Nam, there was a limited impact on notifications in 2020 but a large impact in 2021; while in others such as Mongolia and Myanmar there were reductions that departed from the historic trend in both 2020 and 2021. In most high TB burden countries in the African Region, notifications either fell in line with the historic trend or increased; an exception is Angola. Further analysis of notification trends during the COVID-19 pandemic is provided in Section 1.

Fig. 3.1.2 Notifications of people newly diagnosed with TB (new and relapse cases, all forms) (black) compared with estimated TB incident cases^a (green), 2000–2021, 30 high TB burden countries

The shaded area represents the 95% uncertainty interval.

^a Incidence estimates for India are interim and subject to finalization, in consultation with the Health Ministry & Family Welfare, India.

Globally, the cumulative total number of people diagnosed with TB and officially reported from 2018 to 2021 is 26 million, only 66% of the 5-year target of 40 million between 2018 and 2022 that was set at the UN high-level meeting on TB in 2018 (Fig. 3.1.3). The target for detection and treatment of people with drug-resistant (DR) TB appears even further out of reach, as are the targets for treatment of children specifically.

Fig. 3.1.3 Global progress in the number of people treated for TB between 2018 and 2021, compared with cumulative targets set for 2018–2022 at the UN high-level meeting on TB

Global progress in the number of people treated for TB between 2018 and 2021, compared with cumulative targets set for 2018–2022 at the UN high-level meeting on TB

Most notified cases of TB are among adults (Fig. 3.1.4). Of the global total of people with a new or relapse episode of TB who were notified in 2021, 57% were men, 36% were women and 6.9% were children (aged 0–14 years). In general, notification data appear to understate the share of the TB disease burden accounted for by men, since higher M:F ratios among adults have been found in national TB prevalence surveys (Section 2.4).

Fig. 3.1.4 The global number of people reported to have been treated for TB disease, 2015–2021

The global male:female (M:F) ratio for TB notifications in 2021 was 1.6. The distribution of notified cases by age and sex varies among WHO regions (Fig. 3.1.5).

Fig. 3.1.5 Estimated TB incidence (grey outline) and notification rates (new and relapse cases) by age group and sex^a (female in purple; male in green) in 2021, globally and for WHO regions

^a Data from 24 countries and areas that did not report cases in these age categories are excluded. Cases included accounted for 98% of reported cases.

There is considerable country variation in the proportion of notified cases that are children (Fig. 3.1.6). There are recognized issues with the diagnosis and reporting of TB in children, including the use of variable case definitions and underreporting of cases diagnosed by paediatricians in the public and private sectors. Greater attention to the quality of TB notification data for children is warranted in many countries.

Fig. 3.1.6 Percentage of people with a new or relapse episode of TB who were children (aged 0–14 years), 2021

Map showing percentage of new and relapse TB cases that were children

There is also considerable country variation in the proportion of notified cases that are diagnosed with extrapulmonary TB (Fig. 3.1.7). This may reflect underlying differences in TB epidemiology as well as diagnostic practices.

Fig. 3.1.7 Percentage of people with a new or relapse episode of TB who were diagnosed with extrapulmonary TB at country level, 2021

Map showing percentage of extrapulmonary cases among new and relapse TB cases

Engagement of all care providers in the public and private sectors through public–private mix (PPM) initiatives can help to minimize the underreporting of people diagnosed with TB. Since 2015, the contribution of such initiatives to total notifications has grown in most of the seven countries defined as top global priorities for PPM (Fig. 3.1.8).

Fig. 3.1.8 Contribution of public-private mix to notifications of people diagnosed with TB in priority countries, 2010–2021

Community engagement can help with referrals of people with TB symptoms to health facilities as well as treatment support; in 81 countries from which WHO requested data in 2021, such engagement was reported in a high proportion of basic management units (Fig. 3.1.9).

Fig. 3.1.9 Percentage of basic management units at country level in which there was community contribution to new TB case finding and/or to treatment adherence support,^a 2021

Map showing percentage of management units with community contributions to case finding and/or treatment support

^a Data only requested from 81 countries.

Case-based digital surveillance systems enable timely reporting and use of TB data. The current status of progress in transitioning from paper-based aggregated reporting systems to case-based digital surveillance is shown in Fig. 3.1.10. Acceleration of progress in making this transition is needed in the African Region.

Fig. 3.1.10 Countries with national case-based digital surveillance systems for TB, 2021

Map showing which countries have case-based TB surveillance systems

Further country-specific details about TB notifications are available in the Global tuberculosis report app and country profiles.

Data shown on this webpage are as of 29 August 2022 (see Annex 2 of the main report for more details).