Zika fever is caused by infection with the Zika virus (Zika Virus-ZIKV), a single-stranded RNA virus in the flavivirus family. It is similar to yellow fever virus, dengue virus, West Nile virus, and Japanese encephalitis virus. The Aedes mosquito (such as Ae. Africanus, Ae. Apicoargenteus, Ae. Luteocephalus, Ae. Aegypti, etc.) is the vector. Zika virus was first isolated in 1947 from the serum of a rhesus monkey used in a study of yellow fever in the Zika forest in Uganda. It was isolated from humans in 1968 in Nigeria.

   The incubation period is 4-7 days, after which symptoms appear: fever, severe headache, maculopapular rash on the trunk, limbs, dizziness, conjunctivitis, red eyes, joint pain, swollen lymph nodes, and diarrhea.

   From 1951 to 1992, there were clinical indications of Zika virus infection in African countries including Uganda, Tanzania, Egypt, Central Africa, Sierra Leone and Gabon. In Asia, there were reports of Zika virus infection in India, Malaysia, Philippines, Thailand, Vietnam and Indonesia. Most recently, in 2007, an outbreak of Zika virus was reported in the Yap Islands.

    In Thailand, there was a report of Zika virus neutralizing antibodies in people living in Thailand in 1963. Most recently, there was a report of a female tourist from Canada who traveled to Thailand from January 21 to February 2, 2013 and developed symptoms 4 days after returning to Canada. She became ill on February 5, 2013 with fever, fatigue, headache, restlessness, chills, nausea, vomiting, back pain, and joint pain. She was confirmed to be infected with Zika virus by laboratory testing. The Department of Disease Control is currently monitoring this disease.

    There are two methods of laboratory diagnosis to confirm infection: 1) Genetic testing using the PCR method, which collects serum samples as soon as possible after the onset of symptoms, which should not be more than 9 days after symptoms appear, and 2) Testing for M-type antibodies specific to Zika virus using the ELISA method, which is a method developed by the Centers for Disease Control and Prevention in the United States. Samples are collected twice: the first sample on the day symptoms appear and the second sample 2-3 weeks after the first sample. The National Institute of Health Sciences, Abovirus Division, has a plan to install a laboratory method for Zika fever diagnosis soon. 

    There is currently no vaccine to prevent the disease. Treatment is symptomatic to relieve the symptoms.

Source: http://www.dmsc.moph.go.th/dmsc/news_detail.php?id=1144