After the deadly Ebola outbreak, the global countries’ are now facing yet another disastrous virus outbreak called ‘Zika’ which is capable of devastating a generation. Health experts across the world are in the conclusion that the outbreak could pose a bigger threat to global health than the Ebola epidemic that killed more than 11,000 people in Africa.
The first cases of Zika were reported in Brazil last May with up to 1.5 million people now thought to be affected by the virus which is spread by mosquitoes endemic to Latin America. Brazil is believed to be the country hit hardest by Zika, the outbreak has sparked fear especially among pregnant women after local experts linked the virus to thousands of cases of microcephaly, or abnormally small heads and underdeveloped brains, in newborns.
Prompted by growing concerns and reports of more babies born with unusually small heads, the World Health Organization has declared the Zika virus as an international public health emergency. As many as four million people could be infected by the end of the year. Officials at the Centers for Disease Control and Prevention have urged pregnant women against travel to about two dozen countries, mostly in the Caribbean and Latin America, where the outbreak is growing.
The infection appears to be linked to the development of unusually small heads and brain damage in newborns. However, some health officials also blame the Zika virus for causing Guillain-Barre syndrome, a rare disorder in which the immune system attacks the nervous system, causing weakness and sometimes paralysis. This syndrome directly affects Zika patients themselves. Most recover, but the syndrome is sometimes deadly.
What is Zika virus?
The Zika virus is a mosquito-transmitted infection related to dengue, yellow fever and West Nile virus. Although it was discovered in the Zika forest in Uganda in 1947 and is common in Africa and Asia, it did not begin spreading widely in the Western Hemisphere until last May, when an outbreak occurred in Brazil.
Millions of people in tropical regions of the Americas are now been infected. Yet for most, the infection causes no symptoms and leads to no lasting harm. Scientific concern is focused on women who become infected while pregnant and those who develop a temporary form of paralysis after exposure to the Zika virus.
Brazil has become the worst affected country, with some 4,000 suspected cases of microcephaly, of which 270 have been confirmed, up from 147 in 2014. The WHO said that French Polynesia had also seen a spike in microcephaly cases during a Zika outbreak there two years ago.
The outbreak has sown panic in the Americas, where the WHO says it is “spreading explosively” and predicts up to four million Zika cases this year alone.
Colombia, Ecuador, El Salvador, Jamaica and Puerto Rico have warned women not to get pregnant, while the US Centers for Disease Control and Prevention has advised expectant mothers against traveling to affected countries.
The cause and Spread of Virus
Zika is spread by mosquitoes of the Aedes genus, which can breed in a pool of water as small as a bottle cap and usually bite during the day. The aggressive yellow fever mosquito, Aedes aegypti, has spread most Zika cases. The Asian tiger mosquito, Aedes albopictus, is also known to transmit the virus, but it is not clear how efficiently.
Although the virus is normally spread by mosquitoes, there has been one report of possible spread through blood transfusion and one of possible spread through sex. The virus was found on one occasion in semen. It can also be transmitted from a pregnant mother to her baby during pregnancy or around the time of birth but it is not known how this happens.
The Brazilian researchers had detected the virus in an active form in human saliva and urine samples, but this still remains to be proved.
(Read the full article in the March issue of Safety Messenger Magazine 2016)