Health workers lead passersby to take COVID-19 testing in Kigali, capital of Rwanda, July 2, 2020. Rwanda's Ministry of Health on Thursday launched a COVID-19 street testing survey in Kigali to probe the COVID-19 situation in the city.Photo:Xinhua

A health worker takes a throat swab sample of a passerby for COVID-19 testing in Kigali, capital of Rwanda, July 2, 2020. Rwanda's Ministry of Health on Thursday launched a COVID-19 street testing survey in Kigali to probe the COVID-19 situation in the city.Photo:Xinhua

A health worker takes a throat swab sample of a passerby for COVID-19 testing in Kigali, capital of Rwanda, July 2, 2020. Rwanda's Ministry of Health on Thursday launched a COVID-19 street testing survey in Kigali to probe the COVID-19 situation in the city.Photo:Xinhua

Health workers take throat swab samples of people in a vehicle for COVID-19 testing in Kigali, capital of Rwanda, July 2, 2020. Rwanda's Ministry of Health on Thursday launched a COVID-19 street testing survey in Kigali to probe the COVID-19 situation in the city.Photo:Xinhua