Twenty-six cases of dengue fever have been imported to Hong Kong so far this year, the Department of Health reported on May 12. The patients had visited during the incubation period Thailand (six) Philippines (five) Indonesia and Sri Lanka (four each). Dengue is endemic in some parts of Asia, the department said. In 2017 to date, 9717 cases have been reported in Thailand, 965 cases in Singapore and 62 in Japan.
Symptoms typically show three to 14 days after infection and may include high fever, headache, vomiting, muscle and joint pain and a skin rash. Recovery usually occurs in two to seven days. In a small proportion of cases the disease can develop into potentially fatal dengue haemorrhagic fever, causing severe blood problems leading to shock. Tens of millions of people contract dengue worldwide each year; up to 20,000 may die. The disease is spread by several species of mosquito of the Aedes type and the department issued its usual warnings about mosquito prevention in the environment, covering up and using repellent.