Evolution and Current Scenario of Zika Virus Infection: A Review

Zika virus is a mosquito borne Flavivirus (genus), which belongs to the family Flaviviridae, a member of arbovirus. This genus includes several viruses such as Yellow fever virus, Japanese encephalitis virus, Dengue virus and West Nile virus. In 1947, Zika virus was first isolated in Zika forest, near the Lake Victoria in Uganda from a febrile sentinel Rhesus monkey. In 1948, it was also isolated from a pool of Aedes africanus mosquitoes during a Yellow fever study. In 1952, the virus was first investigated and isolated from humans in East Africa and Uganda respectively. Zika virus was active in several countries in Africa and Asia before spreading to Pacific regions and America. In between 2007-2013, sporadic cases were reported in travelers (Thailand, Cambodia and Indonesia). From April 2007-August 2007, the health care authorities reported 185 cases of Zika virus infection, including 108 confirmed cases on the Island of Yap belongs to the Federal states of Micronesia, in Pacific Ocean. According to WHO, 3 cases were reported in Ahmadabad in India. Currently, the infection is treated only for symptomatic relief such as: Fever is generally managed with damp clothes, light clothing, baths or showers (physical cooling measures). If fever persists paracetamol is recommended. For itchy rash antihistamines like chlorpheneramine is recommended. In case of pregnancy (1st trimester) loratadine and citrizine (H1 antagonists) are usually advised because they do not show any adverse fetal outcome during pregnancy especially regarding teratogenicity. Recently, sofosbuvir an antiviral is clinically approved for treating Zika infection. Other broad spectrum antivirals like ribavarin, interferons and favipiravir are not usually prescribed as they show toxic effects in pregnant women. Novobiocin previously an antibiotic is now used as a potent anti Zika drug. As it is a rare infection which lacks availability of drugs and vaccines due to limited research. To combat complication of Zika virus infection symptomatic treatment is recommended. For implementation of the effective vaccine further research is needed to prevent the morbidity and complications