David Helekal
@dhelekal.bsky.social
Trees, Pathogens, Bayes.
Current: Postdoc @ Harvard Chan SPH
Prev: PhD @ Warwick
Current: Postdoc @ Harvard Chan SPH
Prev: PhD @ Warwick
(7/10) The number of major N. gonorrhoeae lineages carrying tetM also increased from one before 2020 that accounted for ~40% of all tetM+ isolates to 4 after 2020 that collectively accounted for ~80% of all tetM+ isolates. Two of these lineages carry penA variants that increase cephalosporin MICs.
March 28, 2025 at 8:43 PM
(7/10) The number of major N. gonorrhoeae lineages carrying tetM also increased from one before 2020 that accounted for ~40% of all tetM+ isolates to 4 after 2020 that collectively accounted for ~80% of all tetM+ isolates. Two of these lineages carry penA variants that increase cephalosporin MICs.
(5/10) By May 2024, the estimated proportion of isolates carrying tetM skyrocketed to ~35%, suggesting a large selective pressure for doxycycline resistance. The rise seems most pronounced in HHS regions 9 and 10.
March 28, 2025 at 8:43 PM
(5/10) By May 2024, the estimated proportion of isolates carrying tetM skyrocketed to ~35%, suggesting a large selective pressure for doxycycline resistance. The rise seems most pronounced in HHS regions 9 and 10.
(1/10) New preprint: Expansion of tetM-carrying Neisseria gonorrhoeae in the US, 2018-2024; Link: www.medrxiv.org/content/10.1...
March 28, 2025 at 8:43 PM
(1/10) New preprint: Expansion of tetM-carrying Neisseria gonorrhoeae in the US, 2018-2024; Link: www.medrxiv.org/content/10.1...
(7/10) The number of major N. gonorrhoeae lineages carrying tetM also increased from one before 2020 that accounted for ~40% of all tetM+ isolates to 4 after 2020 that collectively accounted for ~80% of all tetM+ isolates. Two of these lineages carry penA variants that increase cephalosporin MICs.
March 28, 2025 at 8:05 PM
(7/10) The number of major N. gonorrhoeae lineages carrying tetM also increased from one before 2020 that accounted for ~40% of all tetM+ isolates to 4 after 2020 that collectively accounted for ~80% of all tetM+ isolates. Two of these lineages carry penA variants that increase cephalosporin MICs.
(5/10) By May 2024, the estimated proportion of isolates carrying tetM skyrocketed to ~35%, suggesting a large selective pressure for doxycycline resistance. The rise seems most pronounced in HHS regions 9 and 10.
March 28, 2025 at 8:05 PM
(5/10) By May 2024, the estimated proportion of isolates carrying tetM skyrocketed to ~35%, suggesting a large selective pressure for doxycycline resistance. The rise seems most pronounced in HHS regions 9 and 10.
For others, we saw evidence that something else was at play, as the dynamics were attributable primarily to factors not included in our model (the ‘residual’):
(13/15)
(13/15)
February 7, 2025 at 9:58 PM
For others, we saw evidence that something else was at play, as the dynamics were attributable primarily to factors not included in our model (the ‘residual’):
(13/15)
(13/15)
Finally, we quantified the extent to which resistance determinants explained each lineage’s success and failure. For some, the determinants we studied explained a lot: (12/15)
February 7, 2025 at 9:58 PM
Finally, we quantified the extent to which resistance determinants explained each lineage’s success and failure. For some, the determinants we studied explained a lot: (12/15)
Some of these findings, such as those involving GyrA determinants, led to hypotheses about relative fitness that we validated in-vitro (11/15)
February 7, 2025 at 9:58 PM
Some of these findings, such as those involving GyrA determinants, led to hypotheses about relative fitness that we validated in-vitro (11/15)
…the mosaic penA 34 that increases cephalosporin MICs… (9/15)
February 7, 2025 at 9:58 PM
…the mosaic penA 34 that increases cephalosporin MICs… (9/15)
Examples include determinants at the gyrA locus that confer fluoroquinolone resistance… (8/15)
February 7, 2025 at 9:58 PM
Examples include determinants at the gyrA locus that confer fluoroquinolone resistance… (8/15)
Our strategy was to define lineages based on AMR determinants and then use phylodynamic modelling to investigate their success and failure over time as treatment changed. An exploratory analysis of a cluster of lineages suggested an alignment between the eff. pop. size and treatment changes.
(6/15)
(6/15)
February 7, 2025 at 9:58 PM
Our strategy was to define lineages based on AMR determinants and then use phylodynamic modelling to investigate their success and failure over time as treatment changed. An exploratory analysis of a cluster of lineages suggested an alignment between the eff. pop. size and treatment changes.
(6/15)
(6/15)
We overcame these challenges by studying the Neisseria gonorrhoeae epidemic in the US. This has many advantages.
Figure Source: Centers for Disease Control and Prevention. Gonococcal Isolate Surveillance Project (GISP) Profiles, 2022. (4/15)
Figure Source: Centers for Disease Control and Prevention. Gonococcal Isolate Surveillance Project (GISP) Profiles, 2022. (4/15)
February 7, 2025 at 9:58 PM
We overcame these challenges by studying the Neisseria gonorrhoeae epidemic in the US. This has many advantages.
Figure Source: Centers for Disease Control and Prevention. Gonococcal Isolate Surveillance Project (GISP) Profiles, 2022. (4/15)
Figure Source: Centers for Disease Control and Prevention. Gonococcal Isolate Surveillance Project (GISP) Profiles, 2022. (4/15)