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Volume 32, Number 6—June 2026

Dispatch

Emergence of Ceftriaxone-Resistant Neisseria gonorrhoeae penA-60–Carrying Strains, Thailand, 2025

Rossaphorn KittiyaowamarnComments to Author , Pongsathorn Sangprasert1, Natnaree Girdthep1, Sirintra Pharanut1, Tawan Nongpian1, Thanakorn Arunngamwong1, Ruechakorn Kunkhajornphan1, Ismael Maatouk1, and Magnus Unemo1
Author affiliation: Bangrak STIs Center, Department of Disease Control, Ministry of Public Health, Bangkok, Thailand (R. Kittiyaowamarn, P. Sangprasert, N. Girdthep, S. Pharanut, T. Nongpian); Bhattamakun Hospital, Chonburi, Thailand (T. Arunngamwong); Patong Hospital, Phuket, Thailand (R. Kunkhajornphan); World Health Organization, Geneva, Switzerland (I. Maatouk); Örebro University, Örebro, Sweden (M. Unemo); University College London Institute for Global Health, London, UK (M. Unemo)

Main Article

Table 2

Diagnostic testing, treatment, and antimicrobial susceptibility of ceftriaxone-resistant Neisseria gonorrhoeae isolates, Thailand, January–April 2025*

Case no. Syphilis rapid test HIV testing NAAT testing† Treatment MIC, µg/mL (R/S)‡ TOC, culture and NAAT† Sexual partner testing
1
 Negative
 Negative
 Pooled specimen from urine and OP site: positive
 IM ceftriaxone 1 g + oral azithromycin 1 g
 CRO 0.25 (R); CFM 1 (R); AZM 256 (R)
 OP and urethral specimens: negative
 Regular female partner (NG detected in pooled cervical and oropharyngeal specimens by Xpert CT/NG assay, but cervical and oropharyngeal cultures negative)
2
 Negative
 Negative
 Not tested
 IM ceftriaxone 1 g + oral doxycycline (200 mg/day for 7 d)
 CRO 0.5 (R); CFM 2 (R); AZM 256 (R)
 OP and urethral specimens: negative
 One-night-stand partner (contact tracing not possible)
3
 Not tested
 Not tested
 Pooled specimen from urine and OP site: positive
 IM ceftriaxone 1 g
 CRO 0.25 (R); CFM 2 (R); AZM 256 (R)
 Not conducted
 No partner reported
4
 Negative
 Negative
 Not tested
 IM ceftriaxone 1 g + oral doxycycline (200 mg/d for 7 d)
 CRO 0.5 (R); CFM 1 (R); AZM 1 (S)
 OP and urethral specimens: negative
 FSW (contact tracing not possible)
5 Not tested Not tested Not tested IM ceftriaxone 1 g + oral doxycycline (200 mg/d for 7 d) CRO 0.5 (R); CFM 2 (R); AZM 0.125 (S) Not conducted Casual female partner (contact tracing not possible)

*AZM, azithromycin; CFM, cefixime; CRO, ceftriaxone; IM, intramuscular; NAAT, nucleic acid amplification test; NG, Neisseria gonorrhoeae; OP, oropharyngeal; R, resistant; S, susceptible; TOC, test-of-cure. †NAAT testing using Xpert CT/NG assay (Cepheid, https://www.cepheid.com). ‡Based on European Committee on Antimicrobial Susceptibility testing breakpoints (10).

Main Article

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Main Article

1These authors contributed equally to this article.

Page created: April 08, 2026
Page updated: May 08, 2026
Page reviewed: May 08, 2026
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