Tuberculosis control in China

Tuberculosis (2003) 83, 15–20

Tuberculosis www.elsevierhealth.com/journals/tube

Tuberculosis control in China Fengzeng Zhao*, Yan Zhao, Xiaoqiu Liu Room 907, Building 24, Panjiayuan Nanli, Chaoyang District, Beijing, China

Tuberculosis (TB) continues to be a disease that seriously affects the health of people and remains a major public health problem in China. In the early 1950s, active pulmonary TB prevalence was 4000–5000/100,000 and the TB mortality was more than 200/100,000 in Beijing and Shanghai. The government of China has consistently attached great importance to the control of TB. A number of policies and regulations governing the control of infectious diseases have been formulated. During 1950–1980, the TB control activities were carried out in cities only. In 1979, the first nationwide random sampling survey for the epidemiology of TB was conducted by the Ministry of Health (MOH). The results showed that the smear-positive TB prevalence was 187/ 100,000 and infectious risk rate was 27.5%. The incidence of pulmonary TB in the countryside was higher than in the city (2.8 : 1). After that, the National TB Program (1981–1990) was designed, and TB control work in the country had laudable achievements through deep reform and opening-up policies. During 1979–1990, TB program activities were carried out as follows: 1. The National Tuberculosis Control Center within the Beijing Tuberculosis Research Institute was established in 1982 and it provided guidance to each province in implementing a national TB control plan. 2. The reporting and recording system was established in 1982. A standard form for reporting data was sent to each province. 3. Short-course chemotherapy (SCC) was introduced in China in the early 1980s and after 1986, it was expanded to most other areas. *Corresponding author. Tel.: +86 10 67781832 E-mail address: [email protected] (F. Zhao).

4. Directly observed treatment was implemented in some cities, such as Beijing municipal area. 5. TB service facilities were established in most provinces (85%) and counties (70%) by 1990. During that time, human resources and technical capacities differed widely between the TB institutions, with much of the difference being due to the availability of funds through the previous TB control programs. The institutions in poorer provinces operated in the context of a weak primary health care infrastructure, the inability of the provinces to provide sufficient financial support, and inadequate supervision due to resource constraints. In 1990, the third epidemiological survey was conducted and it revealed that the TB prevalence in the county was still high and the decline of prevalence was sluggish. Smear-positive pulmonary TB prevalence was 134/100,000. In comparison to the results of the first survey in 1979, the prevalence had been reduced to 28.3% and the annual reduction rate was 3.0%. The prevalence in the countryside was more serious than in the cities. The Second National Tuberculosis Program (1991– 2000) was formally established within the Ministry of Health in 1991. National targets were established and the need to reduce the TB burden by increasing case detection and improving cure rates was highlighted. The DOTS strategy, recognized internationally as a cost-effective mechanism to detect and treat TB cases, was adopted. In order to rapidly expand the implementation of DOTS, the government requested financial support from the World Bank in 1992; 13 provinces, autonomous regions and municipalities negotiated with the World Bank for TB control under the ‘‘World Bank Infectious and Endemic Disease Control (IEDC) project.’’ The World Bank funds supplemented local resources made available for TB

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control. This project adopted the WHO-recommended DOTS strategyFa package of policies for effective TB control. The DOTS strategy has been complemented in areas covering approximately half of China’s population. The major policies in project areas are as follows: 1. A standardized diagnostic evaluation was provided free of charge to patients presenting to the county or district TB dispensary, including chest fluoroscopy, smear examination, and chest X-ray. 2. New patients with smear-positive pulmonary TB received standardized intermittent treatment regimens using streptomycin, isoniazid, pyrazinamide, and rifampin; for retreatment cases, ethambutol was added. 3. Sputum specimens were collected and examined towards achieving sputum conversion and cure. 4. Patients received treatment for each dosage under the village doctor. The number of smearpositive cases registered was 105,262–199,320 per year in the project areas. This project has successfully found and treated more than 1.4 million smear-positive TB cases. The cure rate has reached levels above 85%.

In 1993, the Ministry of Finance increased its allocation to TB control through the national budget. These resources were utilized to promote DOTS expansion in 15 additional provinces, autonomous regions and municipalities covering 140 million people. The project was titled ‘‘Strengthening and Promoting Tuberculosis Control’’. Some of the policies in this project were different from the World Bank project, such as partly free of charge treatment of smear-positive cases. During the implementation of these projects, public policy regarding TB control was also strengthened, giving systemic priority to TB control. In 1996, TB was added to the list of notifiable diseases.

F. Zhao et al.

100 County pop.

80 60 % 40 20 0

91

92

93

94

95

96

97

98

99 2000

Year

Figure 1 DOTS expansion in World Bank Project area by year.

Case-finding from 1991 to 2000 In the World Bank project, 7,995,011 patients with suspected TB were evaluated in TB dispensaries. In all, 1,284,765 smear-positive pulmonary TB cases were diagnosed. Among the smear-positive pulmonary cases, 908,926 were new cases, 92,277 were relapse, and 283,563 were other retreatment cases (Table 1). The rate of new smear-positive cases increased gradually from 10.3/100,000 in 1992 to 27/100,000 in 2000. The new register rate in each province showed a big change compared to the rate prior to the project (Fig. 2). The new register rates in the project area and non-project area were much different (Fig. 3). When the project started, in the first year, among the TB patients diagnosed, the percentage of new cases was less than the percentage of retreatment cases, but following DOTS implementation, the percentage of new cases was increasing (Fig. 4).

Case management and treatment All of the smear-positive TB patients received treatment under DOTs and the cure rate reached levels more than 85% (Table 2). (See also Table 3.)

Evaluation of the DOTS strategy DOTS expansion and coverage Figure 1 summarizes the success of the World Bank project in terms of DOTS expansion and coverage. The project was started in 1991, and within 4 years, DOTS has been extended to 90% of the counties and population.

In 2000, the fourth national survey was conducted. The prevalence of smear positivity declined to 122/ 100,000. This reflects a prevalence of 1.5 million smear-positive TB cases in 2000 (Table 4). The results of this survey showed that the active, smear-positive and bacteriological positive prevalence of pulmonary TB in DOTS areas were

TB control in China

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Table 1 Year

Suspects

Smear-positive

No.

New smear+ no.

Relapse

Other

New smear no.

%

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

14,115 224,321 637,571 703,641 812,336 980,008 1,144,246 1,172,844 1,160,652 1,145,277

770 19,545 74,893 105,262 142,089 174,106 189,196 199,321 190,306 189,278

5.5 8.7 11.7 15.0 17.5 17.8 16.5 17.0 16.4 16.5

333 9721 35,065 59,261 90,175 122,249 140,590 152,691 149,463 149,382

152 3203 7549 8883 10,762 12,016 11,827 12,568 12,151 13,166

285 6621 32,279 37,118 41,152 39,841 36,779 34,062 28,692 26,730

69 7792 28,478 39,360 54,620 65,709 71,762 76,965 82,205 80,698

Total

7,995,011

1,284,765

16.1

908,926

92,277

283,563

507,658

New smear+ no.FNumber of new smear positive cases; OtherFOther re-treatment cases; New smear smear negative cases.

no.FNumber of new

70 60

Before project After project

50 40 % 30 20 10 0

Figure 2 Register rate in each province.

30 New Register 1/100000

DOTS

25

NON-DOTS

20 15 10 5 0

1993

1995

1996

1997

1998

1999

Figure 3 New register rates in DOTS and non-DOTS areas.

significantly lower than in non-project areas (Fig. 5). The difference in smear-positive prevalence between the two areas was significant. Based on

unstandardized data, the prevalence in DOTS areas declined from 142/100,000 in 1990 to 93/100,000 (corrective prevalence) in 2000, and the extent of decline range was 36.1%. However, the prevalence

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F. Zhao et al.

90.0 New

80.0

Ret.

70.0 Percent

60.0 50.0 40.0 30.0 20.0 10.0 0.0 1

2

3

4

5

6 7 Year*

8

9

10

11

Figure 4 Proportion of new to re-treatment cases. *By time, following DOTS implementation in each county.

Table 2 Year

Treatment outcome for new smear positive cases Reg.

Cure

Complete

No.

%

No.

Deaths %

Failure

No.

Default

%

No.

%

Tran. out

Other

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

333 9721 35,065 59,261 90,175 122,249 140,590 152,687 149,463 76,959

311 8652 31,351 54,704 85,256 116,987 135,163 147,375 144,288 74,446

93.3 89.0 89.4 92.3 94.5 95.7 96.1 96.5 96.5 96.7

0 186 778 1006 1244 1293 1586 1614 1762 816

0 1.9 2.2 1.7 1.3 1.0 1.1 1.0 1.1 1.0

6 276 808 1135 1368 1608 1637 1577 1410 631

1.8 2.8 2.3 1.9 1.5 1.3 1.1 1.0 0.9 0.8

11 375 1088 1061 981 994 808 828 690 354

3.3 3.8 3.1 1.7 1.0 0.8 0.5 0.5 0.4 0.4

1 118 616 739 765 814 792 841 797 476

1 23 122 219 231 227 219 208 245 119

3 91 302 397 330 326 385 244 271 117

Total

836,503

798,533

95.4

10,285

1.2

10,456

1.2

7190

0.8

5959

1614

2466

Reg.FAll pulmonary tuberculosis cases detected during the year, and registered by the Tuberculosis Dispensary; DeathsFPatient had died during the treatment course; Tran. outFTransferred out.

Table 3 Year

Treatment outcome for retreatment of smear-positive cases Reg.

Cure No.

Complete

Deaths

Failure

%

No.

%

No.

%

No.

Default

Tran. out

Other

%

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

437 9778 39,592 45,680 51,556 51,628 48,391 46,465 40,681 20,692

346 7767 32,029 39,487 46,601 47,778 45,124 43,520 38,170 19,484

79.1 79.4 80.9 86.4 90.3 92.5 93.2 93.6 93.8 94.1

0 226 1314 1213 1179 944 1013 926 870 472

0 2.3 3.3 2.6 2.2 1.8 2.0 1.9 2.1 2.2

10 452 1544 1346 1229 1007 789 734 614 259

2.2 4.6 3.9 2.9 2.3 1.9 1.6 1.5 1.5 1.2

77 1038 3098 2103 1572 1083 840 717 551 240

17.6 10.6 7.8 4.6 3.0 2.1 1.7 1.5 1.3 1.1

0 130 842 937 549 522 359 337 287 153

2 36 127 153 107 100 100 77 68 34

2 129 638 441 319 194 166 154 121 50

Total

354,900

320,306

90.2

8157

2.3

7984

2.2

11,319

3.1

4116

804

2214

Reg.FAll pulmonary tuberculosis cases detected during the year, and registered by the Tuberculosis Dispensary; DeathsFPatient had died during the treatment course; Tran. outFTransferred out.

TB control in China

Table 4

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Prevalence of pulmonary TB in three surveys (1/100,000)

Categories of pulmonary TB

1979

Active Smear positive Bacteriological positive

1990

717 187 F

2000

523 134 177

423

Corrective prevalence

367 122 160

346 110 143

DOTS areas

450 400

Prevalence

Non-DOTS areas

328

Prevalence

350 300 177

250 141

200

150

110

150 100 50 0 Active

Smear +

Bacter. +

Figure 5 Prevalence of pulmonary TB by areas.

Table 5

Decline of smear-positive prevalence in DOTS and non-DOTS areas

Areas

Smear-positive prevalence (1/100,000)

DOTS areas Non-DOTS areas Whole country

Standard smear-positive prevalence (1/100,000)

1990

2000n

Decrease (%)

Annual reduction rate (%)

1990

2000

Decrease (%)

Annual reduction rate (%)

142 130

93 126

36.1 3.1

4.1 0.1

142 130

79 114

44.4 12.3

5.7 1.3

134

110

F

F

134

97

27.6

3.2

n

Corrected prevalence.

Table 6

Variation of smear-positive prevalence in project and non-project areas

Areas

DOTS areas Non-DOTS areas n

Corrected prevalence.

Smear-positive prevalence (1/100,000) 1990

2000n

192 121

140 130

Standard smear-positive prevalence (1/100,000)

Variation (%) 27.2 +7.3

1990

2000

Variation (%)

192 121

128 135

33.3 +11.7

20

in non-DOTS areas showed no significant change. The prevalence in 1990 was 130/100,000, and it was 126/100,000 in 2000 and the extent of decline was only 3.1% (Table 5). According to the standardized data, the extent of decline of smear-positive prevalence of pulmonary TB in DOTS areas was 44.4%, and it was 12.3% in non-DOTS areas. The national average was 27.6% (Table 5). The above-mentioned situation was particularly significant in the western area of China. There were 12 provinces in the West. Five provinces and municipalities, Gansu, Xinjiang, Sichuan, Chongqing and Ningxia, were involved in the project (DOTS area) and another seven provinces and autonomous regions, Shaanxi, Guizhou, Yunnan, Qinghai, Xizang and Neimeng, were not involved. The difference in the prevalence of TB in the DOTS and non-DOTS areas was very different. The

F. Zhao et al.

prevalence in the DOTS areas decreased from 192/100,000 in 1990 to 140/100,000 in 2000, and the extent of decline was 27.2%. However, the prevalence in the non-DOTS areas rose from 121/ 100,000 in 1990 to 130/100,000 in 2000, i.e. by 7.3%. After standardization the difference was even larger (Table 6).

Conclusion The DOTS strategy has been implemented successfully with half of the population of China. We must continue to expand it to the entire population of China. Only then will we reach the goal of decreasing the incidence of and mortality due to TB.