HIV is the strongest risk factor for developing

HIV is the strongest risk factor for developing
tuberculosis (TB) disease in those with latent
or new Mycobacterium tuberculosis infection.
The risk of developing TB is between 20 and 37 times
greater in people living with HIV than among those
who do not have HIV infection. TB is responsible
for more than a quarter of deaths in people living
with HIV. Relatively more women than men were
detected to have TB in countries with a prevalence
of HIV infection of more than 1%. In response to
the dual epidemics of HIV and TB, the World
Health Organization (WHO) has recommended 12
collaborative TB/HIV activities as part of core HIV
and TB prevention, care and treatment services.
They include interventions that reduce the morbidity
and mortality from TB in people living with HIV, such
as the provision of antiretroviral therapy (ART) and
the Three I’s for HIV/TB: intensified case-finding of
TB (ICF), isoniazid preventive therapy (IPT), and
infection control for TB.
On 25–27 January 2010, WHO conducted a global
policy meeting to review the evidence regarding ICF
and IPT, and to reconceptualize the 1998 WHO/
Joint United Nations Programme on HIV/AIDS
(UNAIDS) Policy on TB prevention. Key questions
were identified and a comprehensive review of
the available scientific evidence was conducted to
formulate the recommendations. The evidence was
evaluated using the Grading of Recommendations
Assessment, Development and Evaluation
(GRADE) criteria. The quality of the evidence was
categorized as high (when further research is very
unlikely to change our confidence in the estimate
of effect), moderate (further research is likely to
have an important impact on our confidence in the
effect) and low (further research is very likely to
have an estimate of effect and is likely to change the
estimate). Reports were also commissioned from
people living with HIV and affected communities
regarding the key questions and the summary of the
evidence. After the initial draft was reviewed by the
Guidelines Group, the comments were incorporated
into a draft that was then sent to over 200 people
for peer review. Comments from around 30 internal
and external peer reviewers were used to finalize
the recommendations. The final recommendations
take into consideration the quality of evidence,
cost, feasibility, and values and preferences of
the community and health-care workers. The
recommendations were classified as strong
when the guidelines group was confident that the
desirable effects of adherence to a recommendation
outweigh the undesirable effects, and as conditional
(weak) when the desirable effects of adherence to
a recommendation probably outweigh the effects,
but the panel was not confident about these tradeoffs.
These new guidelines recommend the use
of a simplified screening algorithm that relies on
four clinical symptoms to identify those eligible for
either IPT or further diagnostic work-up for TB and
other conditions. Chest radiography is no longer
a mandatory investigation before starting IPT. In
contrast to the 1998 Policy, the new guidelines
strongly recommend at least six months of IPT for
children and adults including pregnant women,
people living with HIV and those receiving ART,
and those who have successfully completed TB
treatment. IPT for a duration of 36 months is
conditionally recommended in settings with a high
transmission of TB among people living with HIV. The
revised guidelines also emphasize that a tuberculin
skin test (TST) is not a requirement for initiating IPT
in people living with HIV. However, in some settings
where it is feasible, it can help to identify those who
would benefit most from IPT. The guidelines also
emphasize that IPT is a core component of HIV
prevention and care, and should be the primary
responsibility of AIDS programmes and HIV service
providers. In addition, the provision of IPT should
not be viewed as an isolated intervention for people
living with HIV. Rather, it should be part of a TB
prevention package along with infection control for
TB, ICF and provision of ART.
Executive Summary
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