ZIKV – Emerging Virus May Cause Severe Birth Defects
Posted by feww on December 4, 2015
Brazil records six fold increase in microcephaly: Report
Zika virus is spread to people through mosquito bites. The most common symptoms of Zika virus disease (Zika) are fever, rash, joint pain, and red eye. The illness is usually mild with symptoms lasting from several days to a week, according to CDC.
Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue. The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas. [Edward B. Hayes/CDC]
Zika may be responsible for an “unprecedented epidemic in Brazil and is quickly spreading through Latin America may be responsible for a spike in severe birth defects,” said a report.
Brazilian government has warned that the virus could be responsible for a dramatic rise “in cases of microcephaly, a severe birth defect in which the brain fails to develop properly and the head is much smaller than normal. Children with microcephaly frequently have developmental delays, learning disabilities, impaired motor function, and seizures.” However, the connection remains to be proven.
“Microcephaly can be caused by genetic factors, infections, or injuries. In recent years, there have been between 150 and 200 cases in Brazil per year. As of 30 November, more than 1200 cases had been reported in 10 states, all of which have also reported Zika virus infections, says Ana Maria Bispo de Filippis, head of the flavivirus laboratory at the Oswaldo Cruz Institute in Rio de Janeiro, Brazil.”
Brazil’s northeastern state of Pernambuco has recorded at least 487 microcephaly cases so far this year, compared with an average of 10 cases per year between 2010 and 2014, said the report.
“The virus has been found in the amniotic fluid of two fetuses diagnosed with microcephaly via ultrasound. It has also been found in tissues of a baby with microcephaly that died shortly after birth. It seems that in some cases the virus can cross the placenta and infect the fetus directly, says Patricia Garcez, a neurodevelopment expert at the Federal University of Rio de Janeiro in Brazil. It’s possible that the virus then attacks brain cells, she says. If that happens during the key phases of brain development in the first 3 to 4 months of pregnancy, the overall size of the brain would be dramatically reduced, leading to microcephaly.”
Additionally, health authorities in French Polynesia reported “17 cases of unusual central nervous system birth defects following a Zika outbreak there in 2013 and 2014.”
Unpreventable and Untreatable!
There is no vaccine to prevent or medicine to treat Zika. When traveling to countries where Zika virus or other viruses spread by mosquitoes have been reported, travelers should protect themselves from this disease by taking steps to prevent mosquito bites.
Outbreaks of Zika virus disease (or Zika) previously have been reported in tropical Africa, Southeast Asia, and the Pacific Islands. Zika virus likely will continue to spread to new areas. In May 2015, the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed Zika virus infections in Brazil. [CDC]
Countries that have past or current evidence of Zika virus transmission
AFRICA: Angola*, Burkina Faso, Cameroon, Central African Republic, Cote d’Ivoire, Egypt*, Ethiopia*, Gabon, Gambia*, Kenya*, Nigeria, Senegal, Sierra Leone*, Somalia*, Tanzania*, Uganda and Zambia*
ASIA: Cambodia, India*, Indonesia, Malaysia, Pakistan*, Philippines, Thailand and Vietnam*
AMERICAS: Brazil, Colombia, El Salvador, Guatemala, Mexico, Paraguay and Suriname
OCEANIA/PACIFIC ISLANDS: Cook Islands, Easter Island, Federated States of Micronesia, French Polynesia, New Caledonia, Solomon Islands and Vanuatu
*For these countries, the only evidence of Zika virus transmission is from studies that detected Zika virus antibodies in healthy people. These studies cannot determine where the people were infected or if they were infected with Zika virus because the antibodies may have resulted from infections with other closely related viruses, such as dengue virus.