This presentation is done by Dr.RAJATHISAKTHIVEL M.Sc(N),M.Phil.,Ph.D. Vice-Principal, Hindu Mission College of Nursing , West Tambaram , Chennai-45.

1. Latent TB Infections (LTBI)
Dr. Rajathisakthivel RNM.,M.Phil., Ph.D
Vice-Principal / HOD Child Health Nursing
Hindu Mission College of Nursing
West Tambaram, Chennai
Tamilnadu, India

2. Contents - LTBI
 Definition - latent TB Infection
 Risk factors / High risk groups
 Statistics – Global & National
 Screening modalities
 Treatment Regimen
 Difference - latent and active TB

3.  Tuberculosis - Preventable and treatable, communicable disease
that has two general states: Active and latent infection.
Active Pulmonary TB
Extra Pulmonary TB
Latent TB
 Treatment of LTBI substantially reduces the risk to progress the
active TB disease.
Introduction …..

4. Definition - LTBI
 State of persistent immune response
to stimulation by M. tuberculosis
antigens with no evidence of clinically
manifest active TB.
- WHO
 5-10% - Life time risk of progression
to active disease.

5. Risk factors / High Risk groups
 Recent (less than 5 years) immigrants and
Extended travel from high-incidence
countries.
 Homeless persons, Illicit drug & alcohol &HIV
 DM , RF requiring dialysis ,Gastrectomy
/Jeujenostomy and Bypass
 Recent exposure to TB
 Age less than 5 years
 Organ transplant recipients
 Health care professionals/ persons living or
working in institutional settings.

6. Statistics – Global
World map of countries - Tuberculosis (TB) incidence.
Adam Cohen et al. Eur Respir J 2019;54:1900655
Current Incidence rate – 193 /1,00,000 population in year
Low Incidence rate - 100/ 1,00,000 population in year

7.  In 2019 – 8.9 to 11.0 million in all
countries and age group
5.6 million
3.2 million
1.2 million
 High TB burden countries - 87% new TB
cases.
 Globally, TB incidence is declined to
2% per year. (20% reduction 2015 to 2019)
 2.9 Million undiagnosed – LTBI
Statistics - Global …..

8.  Global prevalence LTBI – 33%.
 2019 WHO – 40% of LTBI children.
24% - 1- 10 years
16% - 11 -15 years
 LTBI treatment - 3.5 lakh children
below age of 5 years
 Reactivation of TB - 5 to 10% ( HIV
parents)
Statistics – Global LTBI …..

9. India accounts for 27% of all estimated
Incident cases worldwide
Statistics – National

10. Current Statistics – Global 2021
• WHO
 Pandemic - Tuberculosis related mortality - i.e., 0.2
to 0.4 million.
 14 high burden TB countries –
 Restriction of movement of people procurement
 Transportation of Tuberculosis medicines and
 Loss of wages - difficult to access health centers.
 44 % New cases - Republic of Philippines,
Republic of Indonesia and South Africa

11. Screening
 Tuberculin skin test (TST )
 15 mm or more - Positive (without risk
factors)
 10 mm or more - Positive (at higher risk)
 5 mm or more - positive for certain high-
risk persons
 QuantiFERON TB - Interferon gamma
release assay ( IGRA)

12. Treatment
Before initiating treatment for LTBI
 Determine prior history of treatment for LTBI or
TB disease
 Completion of therapy is based on the total
number of doses administered, not on duration
alone
 Assess risks and benefits of treatment

13. Treatment…..
Recommended Regimen – LTBI (2020 guidelines)

14. Treatment Guidelines for Latent TB Infection
Drug(s) Duration Interval Minimum
Doses
Isoniazid 9 months Daily 270
Twice
weekly
76
6 months Daily 180
Twice
weekly
52
Isoniazid &
Rifapentine
3 months Once
weekly
12
Rifampicin 4 months Daily 120
 12 dose Regimen (3HP)
 Avoid - Pregnant women or women
expecting to be pregnant within the 12-
week.
 Pregnancy and Breast-Feeding
 9 months of INH daily or twice weekly;
give with vitamin B6
 Breast-feeding not contraindicated
 Rifampicin
 HIV-infected persons receiving PI-
Rifabutin may be substituted.

15. Characteristics Latent TB Active TB
M.Tuberculosis Present - Inactive state Present – Active state , starts multiply
Symptoms
Asymptomatic Present - Cough , Haemoptysis,
Fatigue, Weight loss, No appetite,
Chills, fever & sweating at night
Wellness Not feels sick Feels sick
Spread of infection Not spread TB bacteria to others Spread TB bacteria to others
X - ray
Sputum
Normal
Negative
Abnormal
Positive
TST & Blood test Positive - Indicates TB infection Positive - Indicates TB infection
Treatment Prevent Active TB disease Treat Active TB disease
Difference - Latent & Active TB disease
Difference - Latent & Active TB disease

16. Recap
Identifying LTBI
Prevent Active TB
High-risk populations - Screened for TB
Interferon-gamma release assay (IGRA)
Tuberculin Skin Test (TST)
 Treatment
Monotherapy / 12 dose regimen
 Target Ending TB epidemic by 2035