Taiwan is not a member of the WHO due to the objection of China, which considers the island a Chinese province with no right to participate in international organisations unless it accepts it is part of China.
Tsai, speaking to reporters after Taiwan's Tuesday confirmation of its first case of the coronavirus, a woman returning to Taiwan from Wuhan, said China had to live up to its international obligations.
Tsai said she hoped for transparency and that China would "share with Taiwan correct information about the virus".
"This is also beneficial for China's people. We believe that political considerations should not come before safeguarding people," she said.
Taiwan was a part of the international community and faced the same health challenges and risks as everyone, Tsai said.
"I again call on the WHO not to exclude Taiwan due to political factors. Taiwan is at the forefront of global epidemic prevention. There needs to be room at the WHO for Taiwan's participation."
Relations between Taipei and Beijing have nosedived since Tsai took office in 2016, with China suspecting her of pushing for the island's formal independence. She says Taiwan is already an independent country called the Republic of China, it's formal name.
The WHO office in Beijing did not immediately respond to a request for comment, but WHO spokesman Tarik Jasarevic said in an email to Reuters on Tuesday that Taiwan was being kept informed.
"Taiwanese authorities, including health experts, are being informed through cross-strait channels as well as channels connected with the International Health Regulations. WHO is informed that there is cross-strait contact on this matter."
The deputy head of China's National Health Commission, Li Bin, told reporters in Beijing earlier that experts from Taiwan had been invited to visit Wuhan and the island was being provided with information.
In Taipei, Chuang Jen-hsiang, deputy head of Taiwan's Centres for Disease Control, confirmed health experts from the island had visited China and that they had good communication channels.
But Taiwan is unable to attend emergency meetings arranged by the WHO as it is not a member, he said.
"We have no way to get the information first hand."
Chinese foreign ministry spokesman Geng Shuang said no-one cared more about the wellbeing of people in Taiwan than China, but its participation in international bodies had to happen under the "one China" principle.
Taiwanese medical experts can participate in WHO technical meetings, WHO experts can visit Taiwan for inspections, and Taiwan can promptly receive WHO information on global public health events, Geng said.
Taiwan has advised people not to visit Wuhan unless they absolutely have to and has suspended tourist groups from the city from visiting the island.
Despite political tension, Taiwan and China have close business ties, with billions invested in China by Taiwanese businesses such as Foxconn, a key supplier to Apple.
Foxconn, formally known as Hon Hai Precision Industry Co Ltd, has asked employees from its Wuhan plant in China who are in Taiwan for the Lunar New Year holidays to stay at home given the coronavirus outbreak in the city.
Since the outbreak, Foxconn workers in Wuhan have been wearing facemasks and getting their temperature checked, the world's largest contract electronics manufacturer said.
Terry Gou, the billionaire founder of Foxconn, advised employees not to visit China over the holiday.
"The speed of contagion will be no less than SARS," he said at a party for the Lunar New Year in Taipei, referring to a Severe Acute Respiratory Syndrome (SARS) outbreak that started in China and killed nearly 800 people globally in 2002-2003.
"I advise everyone not to go to the mainland for this coming new year holiday," he said.
Management has to decide whether employees need to return to Wuhan to work after new year, Gou said, adding Foxconn would come up with solutions for employees to work remotely.
Lunar New Year is the biggest holiday in the Chinese-speaking world, when millions of people travel for family reunions in what is the world's largest annual human migration.
(Reporting by Felice Wu and Yimou Lee; Additional reporting by Se Young Lee and Gabriel Crossley in Beijing and Stephanie Nebehay in Geneva; Writing by Ben Blanchard Editing by Himani Sarkar, Robert Birsel) ((firstname.lastname@example.org;))