No new deaths were recorded, with the fatality toll remaining on 36.
The Disease Prevention and Control Center (SPKC) said 2,402 tests had been conducted during the previous 24-hour period.
In total 293,309 tests have been carried out since February 29.
So far 1,248 patients have recovered from infection.
Eight patients are in hospital, all of whom are described as having moderate symptoms of the disease.
Pēdējās 24h veikti 2402 COVID-19 testi, reģistrēti 17 jauni saslimšanas gadījumi. Latvijā kopā veikti 293 309 izmeklējumi, saslimušas 1515 personas un 1248 izveseļojušās, 36 mirušas.
— SPKC.gov.lv (@SPKCentrs) September 19, 2020
The daily count of 17 is the highest since 18 cases were recorded on August 26.
SPKC added that six of the new cases were arrivals from other countries (United Kingdom and Russia), three of the new patients had been in contact with an infected person, while the remaining cases were still being investigated.
On September 18 the 14-day cumulative number of COVID-19 cases per 100,000 of population was 4.4 in Latvia, 18.8 in Lithuania and 25.4 in Estonia according to data from the European Centre for Disease Prevention and Control.
The threshold for the introduction of compulsory self-isolation upon arrival in Latvia is 16. See our other story about the latest list of countries which require self-isolation for people arriving in Latvia. The country list is updated every Friday.
COVID-19 information
A useful summary in English of the latest COVID-19 situation including restrictions in place and rules on public assembly is available at this special government website.
Cīņa ar #COVID19 izplatību nav noslēgusies - iepazīsties ar noteikumiem, kurus nepieciešams ievērot savas un sabiedrības veselības saglabāšanas nolūkā arī pēc ārkārtējās situācijas noslēguma! ☝?
— Valdības māja (@Brivibas36) June 10, 2020
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The number for medical emergencies is 113, the number for enquiring about a COVID-19 test if you have developed some potential symptoms after returning from overseas or being in contact with someone confirmed as having coronavirus is 8303 and the SPKC COVID-19 advice helpline is 67387661.
The SPKC has information in English about the approved methods of protecting yourself from the virus, symptoms and medical procedures and an interactive map plotting the incidence and distribution of the disease in Latvia.