Hawaii officials announced on Friday that a Japanese tourist tested positive for coronavirus after returning home from a trip to Hawaii.News of the man's case comes a day after Hawaii officials announced that the CDC had sent flawed coronavirus testing kits to Hawaii.Faulty testing has led to heightened concerns about the effectiveness of using the testing kits to stop the spread of disease.Visit Business Insider's homepage for more stories.Hawaii officials announced on Friday that a man in his 60s from Japan developed coronavirus symptoms while on vacation in Hawaii.The man, who visited Maui and Oahu from January 28th to February 7th, tested positive for the disease upon his return to Japan. The man had not visited China recently, and Hawaii officials said he was likely infected in Japan or while in transit to Hawaii.Hawaii officials said the man did not have any symptoms while he was traveling in Maui, and he developed mild symptoms while in Oahu.Hawaii Governor David Ige said that despite the case, there has not been a confirmed case of the virus on the island."We are taking the necessary actions we need to in order to ensure the safety of our community," he said.News of the man's case comes a day after Hawaii officials announced that the Center for Disease Control (CDC) sent flawed coronavirus testing kits to Hawaii.Hawaii Lieutenant Governor Josh Green said that testing kits were initially sent to the wrong state, and when they arrived in Hawaii they were reported to be damaged.Beyond Hawaii, the CDC has admitted this week that some coronavirus test kits sent to laboratories around the country did not work properly. The CDC has recommended testing people who exhibit symptoms like fever, cough, or shortness of breath for the virus, though faulty tests have pointed to a major gap in treating and stopping the spread of virus.Is testing effective at preventing the spread of disease if they don't work'Experts say that proper detection of the virus is as importantif not more importantthan developing a vaccine for those who have already been diagnosed.Sharon Lewin, Director at The Peter Doherty Institute for Infection and Immunity in Melbourne, Australia, told Business Insider that while vaccines are being developed to tackle the disease, "good diagnoses are just as important" in preventing the spread of disease.Trudie Lang, Professor of Global Health Research at Oxford University in London, told the BBC Newshour that many people can contract the disease without showing symptoms, making accurate detection of the disease key in fighting the spread of the outbreak. New research from Chinese scientists suggests it could take up to 24 days for symptoms to show up in infected people."There seems to be the case that there a lot of people that have no symptoms that still have the virus," Lang said. "We need very good diagnostic tools everywhere."Lang said one could argue that the value of creating effective diagnostic tools is almost more important than developing a vaccine."Even the value of a drug is questionable when many people don't even have symptoms or are asymptomatic," she said. "The priority is to detect cases and then to isolate them, so in that quest for detection, we need a really good diagnostic."The CDC announced last week that it had shipped 200 test kits to labs across the US, and 200 more to labs in other countries.According to the CDC, each test kit can test approximately 700 to 800 patient specimens.But it's unclear how many of those tests sent out were faulty, leading to heightened concerns about the effectiveness of using the tests to stop the spread of disease."The test is the only way you can definitely know you have the infection," Dr. Jeanne Marrazzo, the director of the infectious diseases division at the University of Alabama at Birmingham, told The New York Times.Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, said during a news conference on Wednesday that some of the CDC tests came back "inconclusive.""When some states were doing this, we received feedback that it wasn't working as expected, specifically some public health labs at states were getting inconclusive results, and what that means is that test results were not coming back as false positive or false negatives, but they were being read as inconclusive," Messonnier said.She did not confirm how many states had faulty testing, or how many people may have been impacted by the error."We're looking into all of these issues to understand what went wrong, and to prevent these same things from happening in the future," she said.Beyond tests that don't work, a woman with coronavirus was erroneously discharged from a San Diego hospital last week because her test was mislabeled.So far, the US has confirmed 15 cases of the virus: eight in California, two in Illinois, and one each in Arizona, Massachusetts, Texas, Washington, and Wisconsin. Twocases of human-to-human transmissionhave been confirmed in the US.As of Friday, the COVID-19 Virus, as it is officially known, has killed 1,523 people and infected nearly 67,000 across 26 countries.Even with testing kits that work well, people in Wuhan, Chinaconsidered to be the epicenter of the virushave likened getting access to those kits to "winning the lottery."Mimi Lau, a reporter at the South China Morning Post, said last month that the shortage of coronavirus test kits are leading to a delay in accurate diagnoses of the disease.The possibility of a large number of undiagnosed cases in China has led the government to use other methods to diagnose the disease, including CT-scans and infrared scanners.SEE ALSO:Wuhan, China, faces such a shortage of coronavirus test-kits that people say getting one is like 'winning the lottery'Join the conversation about this storyNOW WATCH: I switched to Google Photos after using iCloud for 5 years and I'm never going back Click here to read full news..