ON February 1, 2016, the World Health Organisation, WHO, declared the Zika virus infection a public health emergency of international concern, following widespread reports about its suspected role in causing birth defects among newborns when pregnant women are infected. The WHO says it expects 3-4 million Zika infections in the Americas over the next 12 months.
A mosquito-borne illness in the past, Zika virus was only known to cause mild illness, such as fever, rashes, muscle/joint pain, and conjunctivitis. Severe disease and fatalities were uncommon. The mosquito that carries the Zika virus, the Aedes aegypti mosquito, is the same mosquito that spreads the Yellow Fever. It occurs worldwide, posing a high risk of global transmission. The fears of significant international spread by travellers from the Latin American countries to the rest of the world are real.
In recent times, however, concerns have emerged about severe clinical manifestations, including auto-immune-like illnesses and congenital neurological malformations such as microcephaly, a rare birth defect that stunts the growth of a baby’s brain and head. Evidence of the Zika virus has been found in the placenta and amniotic fluid of mothers and in the brains of foetuses or newborns.
Several infected individuals, pregnant and non-pregnant, have been documented after international travel. Over 4,000 cases of suspected microcephaly have been reported to date representing a 20-fold increase from 2010.
Since Brazil reported the Zika virus in May 2015, infections have occurred in at least 24 countries in the Americas. The disease now has “explosive” pandemic potential, with outbreaks reported in Africa, Southeast Asia, the Pacific Islands, and the Americas. It is a worrisome development because there is no vaccine that can prevent the infection and very few tests available to detect it.
Given rapidly evolving epidemiological and virological data of the infection, the issuance of a travel alert by the Minister of Health, Prof. Isaac Adewole, urging pregnant women from Nigeria not to travel to affected parts of the world is proactive and commendable. In the absence of a safe and effective Zika virus vaccine, the declaration of a public health emergency is helping to keep the focus on political attention, while encouraging stakeholder involvement in increasing allocated resources.
A key lesson learned from the 2014 ebola outbreak is the need for an intermediate-level response, avoiding overreaction while still galvanizing appreciable national response. It is expected that the national response would be backed through adoption of stronger health system capacities.
Indeed, Nigeria’s preparedness for Zika virus infection, should reflect intense health information campaigns, backed by accelerated research and development and other core strategies for tackling mosquito-borne diseases in line with international standards. Strategies required for effective mosquito surveillance to ensure focused interventions must be employed without delay.