PMID- 27093296
OWN - NLM
STAT- MEDLINE
DCOM- 20160901
LR  - 20240325
IS  - 1932-6203 (Electronic)
IS  - 1932-6203 (Linking)
VI  - 11
IP  - 4
DP  - 2016
TI  - Tuberculosis Epidemiology at the Country Scale: Self-Limiting Process and the HIV 
      Effects.
PG  - e0153710
LID - 10.1371/journal.pone.0153710 [doi]
LID - e0153710
AB  - BACKGROUND: The global spread of the human immunodeficiency virus (HIV) is the 
      main hypothesis behind tuberculosis (TB) positive trends in the last decades, 
      according to modeling studies and World Health Organization Reports (WHO). On one 
      hand, TB (WHO) reports do not explicitly consider a modeling approach, but cover 
      country and global TB trends. On the other hand, modeling studies usually do not 
      cover the scale of WHO reports, because of the amount of parameters estimated to 
      describe TB natural history. Here we combined these two principal sources of TB 
      studies covering TB High Burden Countries (HBCs) dynamics. Our main goals were: 
      (i) to detect the endogenous component of TB dynamics since 1974 for TB HBCs; and 
      (ii) to explore the HIV exogenous effects on TB models;parameters. METHODS AND 
      FINDINGS: We explored the relationship between the TB per capita population rate 
      of change (RI) and the infectious class size following an endogenous/exogenous 
      framework. RI can be affected by intra-population processes (i.e. competition, 
      predation) and exogenous variables like HIV. We found that TB dynamics had always 
      a strong endogenous component, represented by a negative correlation between TB 
      population size and RI, which was captured by the discrete logistic model. 
      Moreover, we explored the HIV exogenous effects on TB models;parameters. We found 
      that overall the TB+HIV logistic model was more parsimonious than TB model alone, 
      principally in the African region. Our results showed that HIV affected 
      principally TB carrying capacity, as expected by the known HIV effects on TB 
      natural-history. We also tested if DOTS (Directly Observed Treatment Short-Course 
      Strategy), poverty levels and BCG (Bacillus Calmette-Guerin) coverage explained 
      the models  residuals variances, but they did not. CONCLUSIONS: Since 1974, TB 
      dynamics were categorized in distinct chronological domains, with different 
      dynamics but nearly the same underlying mechanism: a negative relationship 
      between RI and infected class size (i.e. self-limiting). In the last decades, not 
      only HIV spread represented a new TB chronological domain, but it also has been 
      pushing TB carrying capacity (K) to higher levels. TB has a complex 
      natural-history and imposes real challenges to model its dynamics. Yet, we were 
      able to explore and reveal the main drivers of TB dynamics for HBCs since 1974, 
      through a simple approach. Based on our results, we suggest that the endogenous 
      view should be considered as a plausible hypothesis to model and explain TB 
      dynamics and that future World Health Organization reports could include the 
      endogenous/exogenous framework as a supplement to help to decipher the main 
      drivers of TB dynamics and other diseases.
FAU - Krsulovic, Felipe Augusto Maurin
AU  - Krsulovic FA
AD  - Pontificia Universidad Catolica de Chile, Santiago, Chile.
FAU - Lima, Mauricio
AU  - Lima M
AD  - Pontificia Universidad Catolica de Chile, Santiago, Chile.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20160419
PL  - United States
TA  - PLoS One
JT  - PloS one
JID - 101285081
RN  - 0 (Antitubercular Agents)
SB  - IM
MH  - Antitubercular Agents/therapeutic use
MH  - HIV Infections/*complications
MH  - Humans
MH  - Tuberculosis/drug therapy/*epidemiology/*etiology
MH  - World Health Organization
PMC - PMC4836699
COIS- Competing Interests: The authors have declared that no competing interests exist.
EDAT- 2016/04/20 06:00
MHDA- 2016/09/02 06:00
PMCR- 2016/04/19
CRDT- 2016/04/20 06:00
PHST- 2015/07/25 00:00 [received]
PHST- 2016/04/01 00:00 [accepted]
PHST- 2016/04/20 06:00 [entrez]
PHST- 2016/04/20 06:00 [pubmed]
PHST- 2016/09/02 06:00 [medline]
PHST- 2016/04/19 00:00 [pmc-release]
AID - PONE-D-15-32705 [pii]
AID - 10.1371/journal.pone.0153710 [doi]
PST - epublish
SO  - PLoS One. 2016 Apr 19;11(4):e0153710. doi: 10.1371/journal.pone.0153710. 
      eCollection 2016.