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Table 2 Incidence and prevalence of active TB disease and latent TB infection in health care workers in South Africa

From: The epidemiology of tuberculosis in health care workers in South Africa: a systematic review

Study ID Study characteristics Study outcomes General comments
National
Claassens et al. [15]
(URC report)
Study date: 2009
133 primary health care facilities in Limpopo, Eastern Cape, Kwazulu-Natal, Mpumalanga and North-West provinces.
No information provided on the health care workers
Incidence of active TB disease (smear positive)
2006: 834 (95%CI 431–1457) per 100,000 persons
2007: 1092 (95%CI 647–1725) per 100,000 persons
2008: 887 (95%CI 517–1420) per 100,000 persons
To compare the TB incidence rate among healthcare workers with the general population the incidence rate was combined for all facilities. For comparison with the general population a standardised incidence ratio was calculated. The standardised incidence ratio for smear positive TB in healthcare workers in:
2006: 2.4 (95%CI 1.2–4.2)
2007: 3.0 (95%CI 1.8–4.7)
2008: 2.3 (95%CI 1.3–3.7)
Dwadwa et al: Health worker access to HIV/TB prevention, treatment and care services in Africa: situational analysis and mapping of routine and current best practices, unpublished
Situational analysis
Study date: 2006
Publicly funded health care facilities in KZN, Limpopo, North West, Northern Cape and Western Cape
Number of participants: 173 health care workers from 10 facilities
Age: Not reported
Sex: Not reported
HIV status: Not reported
Method of TB diagnosis: Unclear
Incidence of active TB disease
2006: Between 1130 and 1470/100,000 staff had been treated for TB during 2006.
In 2006 the national TB case notification rates of South Africa were 719.9 per 100,000.
KwaZulu-Natal
Wilkinson et al. [21] Study date: not reported
Study setting: A district hospital in rural KwaZulu-Natal
Number of participants: 725 total number of staff at risk
22 TB cases from 1991 to 1996
Age: Mean age of staff at risk = 37 years; Mean age of TB cases = 29.6 years
Sex: 36 % of staff at risk was female. 64 % of TB cases were female
HIV status: 59 % of the staff at risk who were tested for HIV were HIV+
54.5 % of TB cases who were tested for HIV were HIV+
Method of diagnosing TB: Smear microscopy, chest X-RAY
Annual incidence of active TB disease
138/100 000 (1991/1992)
Annual incidence of active TB disease
690/100 000 (1993–1996)
1991–1996: Annual incidence of TB in the surrounding community was 1543/100 000.
Mean age of affected health care workers was 29 years
No significant difference in incidence of TB disease between occupational categories
Of the 14 HCWs who were tested for HIV, 12 were HIV-positive
Naidoo et al. [16] Study date: 2004/2005
Study setting: Eight public sector hospitals in Ethekwini municipality, KwaZulu-Natal
Number of participants: 583 cases of HCWs with TB during the study period
Age: HCWs with TB: mean = 37.9 years (range: 21–64)
Sex: HCWs with TB: 64 % female
HIV status: Not reported
Method of diagnosing TB: Not reported
Mean incidence of active TB disease
1133/100 000 (standard deviation: 282.8, 1999–2004)
Mean incidence of TB disease among general population in KZN over study period: 497/100 000
Highest incidence of TB disease in 25–29 year olds (2468/100 000; p = 0.003) and paramedical staff (1558/100 000; not statistically significantly different to the incidence in the other occupational categories).
O’Donnell et al. [17] A public TB referral hospital in KwaZulu-Natal
Number of participants: 4941 total admissions of M(X) DR-TB
231 confirmed HCWs (MDR-TB = 208; XDR-TB = 23)
Age: Median = 35 years
Sex: 78 % female
HIV status: 55 % of HCW with M(X) DR-TB were HIV+
Method of diagnosing TB: Culture confirmed TB with MTB drug susceptibility testing
Annual estimated incidence of MDR-TB hospital admissions among health care workers (2003–2008)
64.8/100 000
Annual estimated incidence of XDR-TB hospital admissions among health care workers (2003–2008)
7.2/100 000
Annual incidence of MDR-TB hospital admissions among the adult general population in KwaZulu-Natal: 11.9/100 000 (I.R.R. 5.56; 95 % CI: 4.86–6.35).
Annual incidence of XDR-TB hospital admissions among adult general population in KwaZulu-Natal: 1.1/100 000 (I.R.R. 6.69; 95 % CI: 4.38–10.2)
Tudor et al. [18] Study date: 2011
Three district hospitals in KwaZulu-Natal, South Africa, with specialized drug-resistant tuberculosis (TB) wards
Number of participants: 1427 HCW occupational health records
Age: Median = 39 years
Sex: 78.05 % female
HIV status: 24 % of HCWs with TB HIV+
Method of diagnosing TB: Not reported
Incidence of active TB disease
1958/100 000 (2010)
2006–2010: 112 (8.53 %) cases of TB, of which 14 (12.5 %) cases were drug-resistant TB.
Incidence of TB disease among the general population of KwaZulu-Natal was 1142/100 000 (2011). Throughout the study period health care workers had significantly higher annual TB incidence rate ratios (IRR) for each year of the study compared to that of the general population in KwaZulu-Natal.
Incidence of active TB in South Africa: 981/100 000 (2010)
Western Cape
Adams: Prevalence and determinants of TB infection in health care workers, unpublished Study date: 2009–2011
7 primary and secondary level health care facilities in the Western Cape province
Number of participants: 505
Age: <30 years (25 %); 31–40 years (27 %); 41–50 years (27 %); >50 years (22 %)
Sex: 74 % female
HIV status: Primary level staff 19 % HIV+; Secondary level staff 2 % HIV+
Method of diagnosing TB: TB infection: TST, QFT-GIT, TSPOT.TB. TB disease: TB symptom screen, Chest X-Ray and 2× sputum culture.
Annual incidence of active TB disease
900/100 000; 95 % CI: 0.2–2.6 (2009–2011)
Prevalence of active TB disease
1400/100 000 (2009–2011)
Prevalence of latent TB infection
84 % (TST; 2009–2011)
Annual incidence of latent TB infection
38 % of HCWs converted from TST negative to positive (2009–20110)
Annual incidence rate in Cape Town 799/100 000 population and Western Cape 935/100 000 population (2008–2011)
3/5 HCWs with active TB were HIV+
9 % of HCWs reported being diagnosed with or on treatment for diabetes
Annual incidence of latent TB infection
QFT-GIT
conversion rate 22 %
reversion rate 7 %
T-SPOT.TB
conversion rate 22 %
reversion rate 16 %
Ayuk et al. [20] Study date: 2008–2011
Tygerberg Academic Hospital, Western Cape province
Number of participants: 249
Age: Mean = 43.8 (range: 23–60) years
Sex: 71.4 % female
HIV status: 30 % HIV+; 63 % HIV-; 6 % unknown
Method of diagnosing TB: smear+; culture+, histology and symptoms
Mean annual incidence rate of active TB disease
2008–2011: 397/100 000 population (95%CI: 307–505 per 100 000; all health care workers)
Incidence rate of active TB disease
Housekeeping staff: 1181/100 000
Nurses: 324/100 000
Doctors: 194/100 000
Annual incidence rate in Cape Town 799/100 000 population and Western Cape 935/100 000 population
Housekeeping staff incidence rate of active TB disease approximately 3 times (95%CI: 2.7–3.3) that of the entire workforce, 3.6 times (95%CI: 3.2–4.1) that of nurses and 6.1 times (95%CI: 5.2–7.1) that of doctors.
Kranzer et al. [6] Study date: 2008/2009
Mobile HIV testing unit (the TUTU tester) provided HIV testing, CD4 counts and TB screening to TB and antiretroviral adherence supporters employed by the TB/HIV Care Association in Cape Town on 8 days in 8 venues in the Western Cape province
Number of participants: 215 community health workers (CHW) were offered HIV and TB testing
Age: Most common age group was 40–49 years old (N = 72, 33 %)
Sex: All female
HIV status: 42 CHW HIV+ (20 %)
Method of diagnosing TB: Smear and culture testing
Prevalence of active TB disease
5 % (10/215; 2008–2009)
 
Naidoo et al. [24] Date of study not reported
Western Cape
Number of participants: 100 randomly selected practicing dentists; 78 % response rate.
Age: Mean = 40 years
Sex: 80 % male
HIV status: Not reported
Method of diagnosing TB: Mantoux and multipuncture tests
Prevalence of latent TB infection
33 % (No dates provided)
 
Mehtar et al. [29] Study date: 2010
Retrospective review of OATB case reports at Tygerberg Academic Hospital in the Western Cape
Number of participants: 67 cases of OATB reported during study period 2008–2010
Age: Not reported
Sex: Not reported
HIV status: Not reported
Method of TB diagnosis: Smear microscopy
Number of occupationally acquired TB cases
2008: 27 TB cases (17 ancilliary staff)
2009: 21 TB cases (7 ancilliary staff)
2010: 19 TB cases (13 ancilliary staff)
Pulmonary TB among health care workers
38.5 % (2008)
27.8 % (2010)
 
Jarand et al. [25] Study date: 1996–2008
Retrospective case record review of patients with XDR-TB from Eastern and Western Cape provinces
Number of participants: 334 XDR-TB patients (10 HCWs with XDR-TB)
Median age: 41 (26–50)
Sex: 90 % female
HIV status: 2/10 HIV+
Method of TB diagnosis: sputum culture
10 of the 334 patients with diagnosed with XDR-TB between 1996 and 2008 were health care workers 5/10 were nurses
4/10 HCWs died
HCW with XDR TB: 26–50 years old; 60 % nursing staff; 80 % HIV-negative
Gauteng
McCarthy et al. [22]
Van Rie et al. [23]
Study date: 2008–2009
Gauteng
Number of participants: 79 medical students and 120 healthcare workers
Age: Medical students median age 22 (22–24)
HCW median age 36 (28–46)
Sex: Medical students = 44 % males
HCW = 10 % males
HIV status: Medical students = 0 % HIV+; HCW = 18.3 % HIV+
Method of diagnosing latent TB: TST and IGRA assay (Quantiferon-TB Gold In-tube)
Incidence of latent TB infection (2008–2009)
26 % (29 per 100 personyears, 95%CI: 20–44, IGRA)
27 % (29 per 100 person years, 95%CI: 19–42, TST)
Prevalence of latent TB infection (2008)
45 % (95%CI: 38–53; IGRA+)
48 % (95%CI: 42–57; TST+)
Incidence of active TB disease (2008–2009)
1.8/100 person years (95%CI: 0.45–7.2) among HCWs
HCWs LTBI prevalence was two-to four-fold higher than medical students
TST: 56.7 % vs. 26.6 %
IGRA: 69.2 % vs. 15.2 %
Limpopo
Malangu et al. [5] Study date: not reported
Data on health care acquired infection submitted to the Compensation Commissioner of the Limpopo province by a health care worker
Number of participants: 56 cases of infectious diseases reported over 2 years.
Age: 42.7 years (mean)
Sex: 67.9 % female
HIV status: Not reported
Method of TB diagnosis: Unclear
2007–2009: Of the 56 reported cases of infectious diseases 47 (83.9 %) were TB cases.
30/47 TB cases were nurses
8/47 TB cases were cleaning staff
Among health professionals, nurses most likely to acquire TB disease; Among non-health professionals cleaning staff most likely to acquired TB disease
Cases were defined as reports about any healthcare acquired infection as submitted for compensation by healthcare workers of Limpopo province.
Mpumalanga
Balt et al. [26] Study date: Not reported
Study setting: 4 dedicated TB centres (SANTA centres) in Mpumalanga
Details of study participants and method of TB diagnosis not reported
Annual incidence of TB disease (1986–1997)
275/100 000 (95 % confidence interval: 33–991)
Between 1986 and 1997: 2 nurses with active TB
The incidence of TB in the general population of Mpumalanga at the time estimated to be 286/100 000
Affected nurses were 36 and 56 years old; both nurses had non-insulin dependant diabetes