Outcomes of latent tuberculosis infection treatment in Istanbul

Background

and

Aim

Increasing the extensity of latent tuberculosis infection (LTBI) treatment which is one of the important parameters of tuberculosis (TB) control and completing the treatment in success are important. The purpose of this study is to evaluate LTBI treatment indications and treatment outcomes of patients who received LTBI treatment in İstanbul between 2016 and 2018.

Methods

The treatment outcomes of people who started LTBI treatment registered in TB dispensaries in Istanbul between 2016 and 2018 were analyzed retrospectively according to the variables of the age groups, gender, dispensary subgroups, and prevention treatment indications. Data collected from the health institutions were evaluated.

Results

26.920 patients received LTBI treatment in all Istanbul TB dispensaries between 2016 and 2018. The evaluation of LTBI treatment indications; contact 15.696, Tuberculin skin test (TST) positivity 2224, immunosuppression 8746, TST conversion 58, sequelae lesion 15, and other indications are identified as 181. The groups which diagnosed with TB disease, mortality, transfer, other, and still in treatment are excluded from the analysis of LTBI treatment outcomes. A total of 25.253 patients were analyzed. 65 percent of the patients had completed LTBI treatment. Variables effective for treatment outcomes are analyzed with logistic regression. Treatment discontinuation was statistically significantly lower in 2017 (odds ratio [OR]: 0.906 confidence interval [CI] [95%] [0.849-0.968]) and 2018 (OR: 0.635 CI [95%] [0.594-0.679]) compared to 2016. Treatment lost to follow-up was statistically significantly lower in those receiving LTBI treatment with the indication of tuberculin skin test positivity (OR: 0.541 CI [95%] [0.487-0.600]) and the indication of immunosuppression (OR: 0.284 CI [95%] [0.142-0.569]) compared to those who received LTBI treatment due to contact. When the treatment results are evaluated according to the TB incidence of the region where the dispensaries are located, treatment lost to follow-up was higher in 101-200 per 100,000 incidence group (OR: 1.201 CI [95%] [1.123-1.285]) and incidence of 201-370 per 100,000 (OR: 1.461 CI [95%] [1.358-1.572]). Treatment lost to follow-up was higher in dispensaries on the European side (OR: 1.293 CI [95%] [1.203-1389]) and the 0-35 age group (OR: 1.248 CI [95%] [1.168-1.333]).

Conclusion

In conclusion, the treatment completion rate should be improved for an effective LTBI treatment which is one of the important parameters of targeted TB elimination. Particularly people under the age of 35 years and regions with high-TB incidence should receive special care and close follow-up.

Pharmacokinetic characterization of favipiravir in patients with COVID-19

This prospective observational study describes the pharmacokinetic characteristics of favipiravir in adult patients hospitalized for mild to moderate COVID-19 with a positive RT-PCR test. Favipiravir was administered for 5 days, with a loading dose of 3200 mg and a maintenance dose of 1200 mg/day. Serial blood samples were collected on Day-2 and Day-4 of the therapy. Laboratory findings of the patients (n=21) and in-hospital mortality were recorded. Favipiravir concentrations exhibited substantial variability and a significant decrease during the treatment of COVID-19. The median favipiravir trough concentration (C_0-trough ) on Day-2 was 21.26 (IQR, 8.37-30.78) μg/mL whereas it decreased significantly to 1.61 (IQR, 0.00-6.41) μg/mL on Day-4, the area under the concentration versus time curve decreased by 68.5%. Day-2-C_0-trough of female patients was higher than male patients. Our findings indicate that favipiravir concentrations show significant variability during the treatment of COVID-19 and therapeutic drug monitoring may be necessary to maintain targeted concentrations.

First known COVID-19 case and contact tracing efforts in İstanbul, Turkey

Background/aim

COVID-19 has now become a global pandemic. Understanding the routes of transmission is vital in the mitigation and suppression of the disease. İstanbul has become one of the disease’s epicenters. This study aims to describe the first COVID-19 case and contact tracing efforts around it in İstanbul.

Materials and methods

The descriptive study was conducted in İstanbul, Turkey. The first COVID-19 cases and those associated with them were investigated with contact tracing, and primary and secondary cases were described.

Results

The source case was an individual who returned to Turkey from international travel at the beginning of March and tested PCR (–). The index case is the brother of the source case and is considered the first PCR (+) case diagnosed in İstanbul. Contact tracing revealed 23 PCR (+) cases, 14 of which resulted in hospitalization and three deaths.

Conclusions

This study described cases of the first COVID-19 cluster in İstanbul. Moreover, contact tracing was used in this first cluster. This contributed to contact tracing algorithms in Turkey.

[Evaluation of Non-Pharmaceutical Interventions for Reducing Contact Rate in COVID-19 Pandemic: R0 Estimation and Modeling for Istanbul]

After the declaration of the coronavirus-2019 (COVID-19) pandemic and the detection of the COVID-19 case in Turkey, a series of non-pharmaceutical measures were implemented to reduce the number of contacts at the national level. The aim of this study was to determine the change in the epidemic reproduction rate (R0) with non-pharmaceutical interventions including curfews starting with the first reported case in Istanbul and to evaluate the effectiveness of interventions by estimating the number of cases and deaths using a dynamic compartmental model. While keeping transmission probability (beta) as 3% and incubation period as seven days, we developed five scenarios that represented nonpharmaceutical interventions The first scenario was "if nothing was done" and the last scenario was "curfew". The contact matrix of 16 age-groups created by Prem et al. was used in the study as the contact matrix of "if nothing was done" as scenario 1. For all other scenarios (2-5) contact matrices assumptions were created and R0 values were calculated for the whole of Istanbul according to age groups for all five scenarios. For each scenario, "the number of cases and COVID-related deaths" for one year from the day the first case was detected were calculated with the mathematical modeling method. In the absence of any intervention, R0 value was estimated as 2.86 in Istanbul. Among age-groups, the largest R0 value was observed in ages 15-19, 10-14, 5-9, 20-24 and the values were 5.22, 4.37, 3.32, and 3.33; respectively. Due to school closings and flexible work hours, R0 values decreased to 2.02, 1.84, 1.63 and 1.85 in the same age-groups. With the addition of a curfew for the population under the age of 20 to the above measures, the R0 values for all age groups were reduced to less than one. When R0 values for Istanbul was 2.86 and 1.55 based on our model results, the number of cases and deaths per year were determined as approximately 14 million and 2 million and 2.5 million and 327.000, respectively. School closures were determined as the most effective non-pharmaceutical intervention. Non-pharmaceutical measures with the addition of curfews under the age of 20 and over the age of 65 to the school closings and flexible working hours were identified as effective methods in controlling the COVID-19 epidemic in Istanbul. While the results of this study may not reflect real life data, it has the potential of helping public health policy makers to decide on which non-pharmaceutical interventions are the most effective.