Katherine Horton
@kchorton.bsky.social
Infectious disease epidemiologist | Assistant Professor in #TB modelling @lshtm.bsky.social | Mama to 👦👦👦🐶
Across age groups, TB exposure typically peaked in adolescence. However, transmission contributions by age varied across regions with the highest proportion from adolescents aged 15-24 in AMR and SEAR, adults aged 35-44 in AFR and EUR, and older adults 65+ in EMR and WPR.
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
October 12, 2025 at 12:51 PM
Across age groups, TB exposure typically peaked in adolescence. However, transmission contributions by age varied across regions with the highest proportion from adolescents aged 15-24 in AMR and SEAR, adults aged 35-44 in AFR and EUR, and older adults 65+ in EMR and WPR.
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
4/ The stability of pooled estimates doesn't mean sex ratios have remained consistent. We found evidence that male-to-female ratios likely increased 1.6% (95% CrI -1.0-6.2%) annually over the period 1994–2021, with the greatest increase in the Western Pacific region.
NOT PEER REVIEWED
NOT PEER REVIEWED
September 16, 2025 at 11:50 AM
4/ The stability of pooled estimates doesn't mean sex ratios have remained consistent. We found evidence that male-to-female ratios likely increased 1.6% (95% CrI -1.0-6.2%) annually over the period 1994–2021, with the greatest increase in the Western Pacific region.
NOT PEER REVIEWED
NOT PEER REVIEWED
2/ We updated our systematic review and identified 99 TB prevalence surveys reporting sex-disaggregated results (with >4 million participants) conducted between 1993 and 2024 in 33 low- or middle-income countries.
NOT PEER REVIEWED
NOT PEER REVIEWED
September 16, 2025 at 11:50 AM
2/ We updated our systematic review and identified 99 TB prevalence surveys reporting sex-disaggregated results (with >4 million participants) conducted between 1993 and 2024 in 33 low- or middle-income countries.
NOT PEER REVIEWED
NOT PEER REVIEWED
ICERs varied widely by intervention and across countries. Shortened DR-TB treatment was cost-saving in all 3 countries, with the next lowest ICERs for screening in prisons [BRA] (US$72/DALY) and nutritional supplementation [IND] (US$167/DALY). 6/9
September 5, 2025 at 10:05 AM
ICERs varied widely by intervention and across countries. Shortened DR-TB treatment was cost-saving in all 3 countries, with the next lowest ICERs for screening in prisons [BRA] (US$72/DALY) and nutritional supplementation [IND] (US$167/DALY). 6/9
Only three interventions prevented >10% of incident TB episodes by 2050: vaccination (median 15-28% across countries), community screening (32-38%), and screening in prisons (23%). Other interventions had limited impact, from 0% (shortened DS-TB treatment) to 5% (nutritional supplementation). 5/9
September 5, 2025 at 10:05 AM
Only three interventions prevented >10% of incident TB episodes by 2050: vaccination (median 15-28% across countries), community screening (32-38%), and screening in prisons (23%). Other interventions had limited impact, from 0% (shortened DS-TB treatment) to 5% (nutritional supplementation). 5/9
We developed a deterministic #TB model for a geographically and epidemiologically diverse set of countries, incorporating key structural determinants: incarceration in Brazil, undernutrition in India, HIV in South Africa. We calibrated to epidemiological indicators and trends for each country. 2/9
September 5, 2025 at 10:05 AM
We developed a deterministic #TB model for a geographically and epidemiologically diverse set of countries, incorporating key structural determinants: incarceration in Brazil, undernutrition in India, HIV in South Africa. We calibrated to epidemiological indicators and trends for each country. 2/9
We also observe that incidence and mortality may rebound when screening with bacteriology-based algorithms ends, likely due to the reservoir of individuals with non-infectious TB, so strategies are needed to ensure reductions in morbidity and mortality are sustained. 5/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
August 27, 2025 at 2:55 PM
We also observe that incidence and mortality may rebound when screening with bacteriology-based algorithms ends, likely due to the reservoir of individuals with non-infectious TB, so strategies are needed to ensure reductions in morbidity and mortality are sustained. 5/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
Our findings highlight the importance of algorithms that reach individuals who do not report symptoms, as well as the potential value of developing algorithms for non-infectious TB, for which low diagnostic accuracy led to prohibitive overdiagnosis in our work. 4/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
August 27, 2025 at 2:55 PM
Our findings highlight the importance of algorithms that reach individuals who do not report symptoms, as well as the potential value of developing algorithms for non-infectious TB, for which low diagnostic accuracy led to prohibitive overdiagnosis in our work. 4/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
We show that algorithms targeting lower disease thresholds achieve greater epidemiological impact with lower coverage and/or duration than algorithms targeting higher disease thresholds. 3/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
August 27, 2025 at 2:55 PM
We show that algorithms targeting lower disease thresholds achieve greater epidemiological impact with lower coverage and/or duration than algorithms targeting higher disease thresholds. 3/n
[NOT YET PEER REVIEWED]
[NOT YET PEER REVIEWED]
This acknowledgement is an important step towards recognising and taking action to address the clear evidence of men's higher burden of TB disease and (in most settings) more limited access to diagnosis and treatment.
July 25, 2025 at 10:52 AM
This acknowledgement is an important step towards recognising and taking action to address the clear evidence of men's higher burden of TB disease and (in most settings) more limited access to diagnosis and treatment.
In our latest personal view in @lancetrespirmed.bsky.social, we argue for the inclusion asymptomatic #tuberculosis in vaccine trial endpoints to potentially reduce the size, length, and cost of trials.
doi.org/10.1016/S221...
@lshtm-tbmod.bsky.social @tb-lshtm.bsky.social
doi.org/10.1016/S221...
@lshtm-tbmod.bsky.social @tb-lshtm.bsky.social
July 4, 2025 at 11:25 AM
In our latest personal view in @lancetrespirmed.bsky.social, we argue for the inclusion asymptomatic #tuberculosis in vaccine trial endpoints to potentially reduce the size, length, and cost of trials.
doi.org/10.1016/S221...
@lshtm-tbmod.bsky.social @tb-lshtm.bsky.social
doi.org/10.1016/S221...
@lshtm-tbmod.bsky.social @tb-lshtm.bsky.social
New systematic review led by @hannahrickman.bsky.social shows annual risk of Mycobacterium #tuberculosis conversion in men and women diverges during adolescence and remains higher among men throughout adulthood.
www.thelancet.com/journals/lan...
www.thelancet.com/journals/lan...
July 2, 2025 at 2:57 PM
New systematic review led by @hannahrickman.bsky.social shows annual risk of Mycobacterium #tuberculosis conversion in men and women diverges during adolescence and remains higher among men throughout adulthood.
www.thelancet.com/journals/lan...
www.thelancet.com/journals/lan...
While we found no association between GEMS score and TB testing history among women, men with more inequitable views appeared somewhat more likely to self-report previous TB testing. This finding was consistent across age groups and HIV status.
May 6, 2025 at 5:58 PM
While we found no association between GEMS score and TB testing history among women, men with more inequitable views appeared somewhat more likely to self-report previous TB testing. This finding was consistent across age groups and HIV status.
We assessed perceptions of gender equitable norms within a community prevalence survey in Blantyre, Malawi, using a modified version of the Gender Equitable Men Scale (GEMS). We found high levels of gender inequitable views among both men and women.
May 6, 2025 at 5:58 PM
We assessed perceptions of gender equitable norms within a community prevalence survey in Blantyre, Malawi, using a modified version of the Gender Equitable Men Scale (GEMS). We found high levels of gender inequitable views among both men and women.
Just as the burden of #TB is inequitably distributed, we project reductions in international donor funding to have the most severe impact on low-income countries and countries in the Africa, South East Asia, and Eastern Mediterranean regions. 5/8
April 27, 2025 at 6:16 AM
Just as the burden of #TB is inequitably distributed, we project reductions in international donor funding to have the most severe impact on low-income countries and countries in the Africa, South East Asia, and Eastern Mediterranean regions. 5/8
Reductions in contributions to The Global Fund in line with current announcements by the United States, France, the United Kingdom, and Germany may lead to an additional 699,200, 63,100, 50,500, and 30,500 TB deaths, respectively. (See table for episodes of disease and other donor countries.) 4/8
April 27, 2025 at 6:16 AM
Reductions in contributions to The Global Fund in line with current announcements by the United States, France, the United Kingdom, and Germany may lead to an additional 699,200, 63,100, 50,500, and 30,500 TB deaths, respectively. (See table for episodes of disease and other donor countries.) 4/8
New pre-print modelling impact of US funding cuts on HIV, #TB, MCH and family planning. We estimate impact of termination of US funding to NTPs via #USAID & The Global Fund may lead to 2.2 (1.5-2.9) million excess TB deaths between 2025 and 2040, reversing over a decade of progress.
bit.ly/4lowp18
bit.ly/4lowp18
April 9, 2025 at 8:32 AM
New pre-print modelling impact of US funding cuts on HIV, #TB, MCH and family planning. We estimate impact of termination of US funding to NTPs via #USAID & The Global Fund may lead to 2.2 (1.5-2.9) million excess TB deaths between 2025 and 2040, reversing over a decade of progress.
bit.ly/4lowp18
bit.ly/4lowp18
Thanks, Santa! 🤩 (and @bittersouth.bsky.social)
December 26, 2024 at 3:47 PM
Thanks, Santa! 🤩 (and @bittersouth.bsky.social)
Men account for 37% of the global population but 55% of people who develop #TB annually. Men are less likely than women to have access to timely diagnosis and treatment, so 70% of people with undiagnosed infectious #TB are men. Among those who do access treatment, men generally have worse outcomes.
November 19, 2024 at 1:01 PM
New estimates of *viable* Mtb infection burden from @aschwalbc.bsky.social
November 17, 2024 at 12:58 PM
New estimates of *viable* Mtb infection burden from @aschwalbc.bsky.social
Don't miss @lightontb.bsky.social this afternoon at the Union - "Assessing the epidemiological impact of strategies to address social and structural determinants: the underutilised role of modelling"
November 16, 2024 at 12:53 AM
Don't miss @lightontb.bsky.social this afternoon at the Union - "Assessing the epidemiological impact of strategies to address social and structural determinants: the underutilised role of modelling"
If you're at the Union Conference, join us at 12:30 in Frangipani for the Gender Equity in TB Working Group meeting!
November 14, 2024 at 3:42 AM
If you're at the Union Conference, join us at 12:30 in Frangipani for the Gender Equity in TB Working Group meeting!
Great to see @lightontb.bsky.social represented at the Nigeria NTP's booth at this year's Union Conference!
November 13, 2024 at 9:04 AM
Great to see @lightontb.bsky.social represented at the Nigeria NTP's booth at this year's Union Conference!