From 71 laboratory-confirmed cases, we found three presymptomatic patients and 10 entirely asymptomatic infections. In two of the three incubation period patients, the viral titer in the presymptomatic period was very high (Ct value 35 RT-PCR within 14 days after diagnosis. Patients who have COVID-19 may already be infectious before there are symptoms, and 14 days of isolation after diagnosis may be sufficient in entirely asymptomatic cases.

Sung HK, et al. J Korean Med Sci. 2020 Jul;35(30):e280. https://doi.org/10.3346/jkms.2020.35.e280

Cheong HS, et al. Infect Chemother. 2022 Dec;54(4):637-673. https://doi.org/10.3947/ic.2022.0171

There are no well-matched, controlled studies comparing azithromycin with doxycycline for the treatment of complicated scrub typhus. A retrospective propensity score-matched case-control study was performed for patients who presented with complicated scrub typhus and were treated with doxycycline or azithromycin between 2001 and 2011. Data on comorbidities, clinical manifestations, laboratory studies, treatments, and outcomes were extracted for analysis. The clinical characteristics and outcomes of the azithromycin-treated group ( n = 73) were compared to those of the doxycycline-treated group ( n = 108). Of 181 patients, 73 from each group were matched by propensity scores. There were no significant differences in baseline characteristics between the matched groups. The treatment success and survival rates were not significantly different (89% [65/73 patients] versus 96% [70/73 patients] and 96% [70/73 patients] versus 96% [70/73 patients], respectively [ P > 0.05]). No difference was observed in the time to defervescence or length of hospital stay between the two groups ( P > 0.05). In complicated scrub typhus patients ( n = 181), multivariate analysis showed that only APACHE II score was an independent risk factor for mortality (95% confidence interval, 1.11 to 1.56; P < 0.001). Our data suggest that outcomes of azithromycin therapy are comparable to those of doxycycline therapy in patients with complicated scrub typhus.