Artemisinin resistance in Plasmodium falciparum is associated with nonsynonymous mutations in the Kelch 13 ( K13 ) propeller domain. We found that 12.1% (8/66) of clinical P. falciparum isolates from Huye district, Rwanda, exhibited K13 mutations, including R561H, a validated resistance marker. K13 mutations appear to be increasing in this region.

Background School attendance during the COVID-19 pandemic is intensely debated. Aim In November 2020, we assessed SARS-CoV-2 infections and seroreactivity in 24 randomly selected school classes and connected households in Berlin, Germany. Methods We collected oro-nasopharyngeal swabs and blood samples, examining SARS-CoV-2 infection and IgG antibodies by RT-PCR and ELISA. Household members self-swabbed. We assessed individual and institutional prevention measures. Classes with SARS-CoV-2 infection and connected households were retested after 1 week. Results We examined 1,119 participants, including 177 primary and 175 secondary school students, 142 staff and 625 household members. SARS-CoV-2 infection occurred in eight classes, affecting each 1–2 individuals. Infection prevalence was 2.7% (95% confidence interval (CI): 1.2–5.0; 9/338), 1.4% (95% CI: 0.2–5.1; 2/140), and 2.3% (95% CI: 1.3–3.8; 14/611) among students, staff and household members. Six of nine infected students were asymptomatic at testing. We detected IgG antibodies in 2.0% (95%CI: 0.8–4.1; 7/347), 1.4% (95% CI: 0.2–5.0; 2/141) and 1.4% (95% CI: 0.6–2.7; 8/576). Prevalence increased with inconsistent facemask-use in school, walking to school, and case-contacts outside school. For three of nine households with infection(s), origin in school seemed possible. After 1 week, no school-related secondary infections appeared in affected classes; the attack rate in connected households was 1.1%. Conclusion School attendance under rigorously implemented preventive measures seems reasonable. Balancing risks and benefits of school closures need to consider possible spill-over infection into households. Deeper insight is required into the infection risks due to being a schoolchild vs attending school.

Objective In Berlin, the first public SARS-CoV-2 testing site started one day after the first case in the city occured. We describe epidemiological and clinical characteristics and aim at identifying risk factors for SARS-CoV-2 detection during the first six weeks of operation. Methods Testing followed national recommendations, but was also based on the physician´s discretion. We related patient characteristics to SARS-CoV-2 test positivity for exploratory analyses using a cross-sectional, observational study design. Results Between March 3 and April 13, 2020, 5179 patients attended the site (median age 34 years; IQR 26-47 years). The median time since disease onset was 4 days (IQR 2-7 days). Among 4333 patients tested, 333 (7.7%) were positive. Test positivity increased up to 10.3% (96/929) during the first three weeks and then declined, paralleling Germany’s lock-down and the course of the epidemic in Berlin. Strict adherence to testing guidelines resulted in 10.4% (262/2530) test positivity, compared to 3.9% (71/1803) among patients tested for other indications. A nightclub was a transmission hotspot; 27.7% (26/94) of one night’s visitors were found positive. Smell and/or taste dysfunction indicated COVID-19 with 85.6% specificity (95%CI 82.1-88.1%). Some 4% (14/333) of those infected were asymptomatic. Risk factors for detection of SARS-CoV-2 infection were recent contact to a positive case (second week after contact, OR 3.42; 95%CI 2.48-4.71), travel to regions of high pandemic activity (e.g. Austria, OR 4.16; 95%CI 2.48-6.99), recent onset of symptoms (second week, OR 3.61; 95%CI 1.87-6.98), and an impaired sense of smell/taste (4.08; 95%CI 2.36-7.03). Conclusions In this young population, early-onset presentation of COVID-19 resembled flu-like symptoms, except for smell and/or taste dysfunction. Risk factors for SARS-CoV-2 detection were return from regions with high incidence and contact to confirmed SARS-CoV-2 cases, particularly when tests were administered within the first two weeks after contact and/or onset of symptoms.