Information of Ebola virus

EBOLA VIRUS

INTRODUCTION

The Ebola virus disease, formerly called the Ebola hemorrhagic fever, was first identified in rural Zaire (now the Democratic Republic of Congo) in 1976. The disease had mostly been confined to relatively small outbreaks in rural settings until its 2014 outbreak, which hit urban areas in Guinea, Liberia, and Sierra Leone, infecting more than 28,600 people and killing more than 11,300 by the end of 2015. The World Health Organization (WHO), which was criticized for its slow response to the epidemic, called the outbreak "the most severe, acute health emergency seen in modern times." In January 2016, West Africa was declared free of the disease, although officials warned that small flare-ups were likely. As the outbreak waned, health officials looked to learn from the uneven international response and prepare for future pandemics.

What is Ebola?

Ebola is a severe and often fatal illness that attacks the immune system and causes extreme fluid loss in its victims. The disease disrupts the blood-clotting system, which can lead to internal and external bleeding. Early symptoms include fever, muscle pain, headache, and sore throat, and are followed by vomiting, diarrhea, rash, and bleeding. Most fatalities are caused by severe dehydration or low blood pressure related to fluid loss. The virus is named after the Ebola River in the Congolese region where it was first identified. The largest outbreak prior to 2014 was in Uganda in 2000, in which 425 people were infected and 224 died.

How is it transmitted?

Ebola is transmitted through bodily fluids from an infected person with apparent symptoms or by handling a victim's corpse. Unlike the common flu and the measles, Ebola is relatively difficult to contract. In October 2014 the New England Journal of Medicine estimated the infection rate (denoted as R0) in this outbreak was between R1.7and R2 in Liberia, Sierra Leone, and Guinea; on average, each sick person infected between 1.7 ana 2 other people. An outbreak is considered "out of control" once it passes R2.

Vaccinations and treatments for Ebola have undergone clinical trials, and health workers have used ring vaccination—vaccinating primary and secondary contacts of infected persons—to contain the disease. The U.S. Food and Drug Administration (FDA) in September 2015 awarded fast-track status to ZMapp, an experimental drug used to treat some cases of Ebola. Treatments also include rehydration and plasma infusions from Ebola survivors, who are believed to possess antibodies to the disease

Why did the outbreak occur in West Africa?

The outbreak is believed to have started in December 2013 in a Guinean village in the prefecture of Gueckedou, near the Liberian and Sierra Leonean borders. The New England Journal of Medicine traced the disease to a two-year-old boy who died on December 6; he and his family were never tested for the disease, although their symptoms were consistent with those of Ebola (his mother, sister, and grandmother subsequently became sick and died). Researchers do not know how the family caught the virus, which can be contracted from contact with primates, bats, or contaminated food.