A Zika virus vaccine is designed to prevent the symptoms and complications of Zika virus infection in humans. As Zika virus infection of pregnant women may result in congenital defects in the newborn, the vaccine will attempt to protect against congenital Zika syndrome during the current or any future outbreak. As of April 2019, no vaccines have been approved for clinical use, however a number of vaccines are currently in clinical trials. The goal of a Zika virus vaccine is to produce specific antibodies against the Zika virus to prevent infection and severe disease. The challenges in developing a safe and effective vaccine include limiting side effects such as Guillain-Barré syndrome, a potential consequence of Zika virus infection. Additionally, as dengue virus is closely related to Zika virus, the vaccine needs to minimize the possibility of antibody-dependent enhancement of dengue virus infection.
The highest risk is to pregnant women due to the connection the virus has with serious birth defects. Pregnant women who contract the virus have a high possibility of giving birth to a baby with microcephaly, a neurodevelopment disorder, where a baby is born with an unusually small head due to abnormal brain development in the womb or after birth. Complications of this disorder include seizures and developmental issues.
Due to the serious nature of global risk, the WHO has declared the microcephaly cases associated with the Zika virus a Public Health Emergency of International Concern (PHEIC). With no vaccines or cure the virus and its risks are expected to continue to spread. The WHO is predicting up to 4 Million Zika cases in the Americas by 2016 and the World Bank is projecting the short-term economic impact for 2016, in Latin America and the Caribbean to be about US$3.5 Billion.
