Contact tracing and population screening for tuberculosis – who should be assessed?

Abstract

Benjamin R. Underwood, Veronica L. C. White, Tim Baker, Malcolm Law
and John C. Moore-Gillon

Background The aim of the study was to investigate the
relative effectiveness of four strategies in detecting and preventing
tuberculosis: contact tracing of smear-positive pulmonary
disease, of smear-negative pulmonary disease and
of non-pulmonary disease, and screening new entrants.
Methods An analysis of patient records and a TB database
was carried out for an NHS Trust-based tuberculosis service
in a socio-economically deprived area. Subjects were contacts
of all patients treated for TB between 1997 and 1999.
New entrants were screened in 1999. Outcomes measured
were numbers of cases of active tuberculosis detected and
numbers of those screened given chemoprophylaxis.
Results A total of 643 contacts of 227 cases of active TB were
seen, and 322 new entrants to the United Kingdom. The highest
proportion of contacts requiring full treatment or chemoprophylaxis
were contacts of smear-positive index cases (33
out of 263 contacts; 12.5 per cent). Tracing contacts of those
with smear-negative pulmonary tuberculosis (12 out of 156;
7.7 per cent) and non-pulmonary disease (14 out of 277;
6.2 per cent) was significantly more effective in identifying
individuals requiring intervention (full treatment or chemoprophylaxis)
than routine screening of new entrants (10 out
of 322; 3.1 per cent).
Conclusions Screening for TB of new entrants to the United
Kingdom is part of the national programme for control and
prevention of TB, whereas tracing contacts of those with
smear-negative and non-pulmonary disease is not. This study
demonstrates that, in our population, the contact-tracing
strategy is more effective than new entrant screening. It is not
likely that the contacts have caught their disease from the
index case, but rather that in high-incidence areas such as
ours such tracing selects extended families or communities at
particularly high risk.
Keywords: tuberculosis, contact tracing, immigrants, cost
effectiveness

Americans’ Knowledge and Perceived Risk of Tuberculosis

Abstract Tuberculosis (TB) has resurged as a major public
health problem in the United States, but there is minimal
information on the public’s knowledge of TB. The general
population must become aware of the seriousness of the
reemergence of TB. Using data from the National Health
Interview Survey Supplement, this study examined knowledge
and perceived risk of TB of 14,727 U.S. respondents. Results
demonstrated some general knowledge of TB, several misconceptions,
and low concern regarding their risk of contracting TB.
Only 10.2% of the respondents perceived risk for themselves.
Respondents reported perceived knowledge of TB at a high level,
while their actual knowledge was lower. Gender, education,
income, and ethnicity were associated with knowledge and
perceived risk. Older people responded correctly to questions
about TB knowledge more often than younger people. Conclusions
were that public health nursing efforts need to be redirected
toward health education regarding TB risk and spread, complementing
existing screening and therapy programs.

Factors influencing health care workers’ adherence to work site tuberculosis screening and treatment policies

Heather A. Joseph, MPH,a Robin Shrestha-Kuwahara, MPH,a Diane Lowry, MPH, MSW,a Lauren A. Lambert, MPH,a
Adelisa L. Panlilio, MD, MPH,b Beth G. Raucher, MD, MSHCM,c James M. Holcombe, MPPA,d Jan Poujade, RN, MS,e
Diane M. Rasmussen, RN,f and Maureen Wilce, MSa
Atlanta, Georgia, New York, New York, Jackson, Mississippi, Portland, Oregon, and Kansas City, Missouri
Background: Despite the known risk of tuberculosis (TB) to health care workers (HCWs), research suggests that many are not fully
adherent with local TB infection control policies. The objective of this exploratory study was to identify factors influencing HCWs’
adherence to policies for routine tuberculin skin tests (TSTs) and treatment of latent TB infection (LTBI).
Methods: Sixteen focus groups were conducted with clinical and nonclinical staff at 2 hospitals and 2 health departments.
Participants were segmented by adherence to TST or LTBI treatment policies. In-depth, qualitative analysis was conducted to
identify facilitators and barriers to adherence.
Results: Among all focus groups, common themes included the perception that the TSTwas mandatory, the belief that conducting
TSTs at the work site facilitated adherence, and a general misunderstanding about TB epidemiology and pathogenesis. Adherent
groups more commonly mentioned facilitators, such as the perception that periodic tuberculin skin testing was protective and the
employee health (EH) provision of support services. Barriers, such as the logistic difficulty in obtaining the TST, the perception that
LTBI treatment was harmful, and a distrust of EH, emerged consistently in nonadherent groups.
Conclusions: This information may be used to develop more effective interventions for promoting HCW adherence to TB
prevention policies. Informed efforts can be implemented in coordination with reevaluations of infection control and EH programs
that may be prompted by the publication of the revised TB infection control guidelines issued by the Centers for Disease Control
and Prevention in 2005. (Am J Infect Control 2004;32:456-61.)