Evolution of an epidemic

Dec. 28, 2013

Emile, a 2- year- old boy in Guinean village of Meliandou, dies of a mysterious sickness, becoming West Africa’s first Ebola victim.

Early 2014

Amid a multitude of deadly diseases, Ebola spreads without being noticed.

March 23

The World Health Organization publishes notification of a “rapidly evolving” Ebola outbreak in Guinea involving 49 patients and 29 deaths. Suspected cases in Sierra Leone and Liberia are being investigated.

March 30

The WHO reports that two Liberians tested positive for the Ebola virus after traveling to Guinea, including a 35-year- old woman who died March 21.

About May 10

Dozens of mourners attend the funeral of a traditional healer who contracted Ebola while treating patients. The funeral, in Koindu, Sierra Leone, helps the virus spread andmaybe linked to 365 Ebola deaths, local health authorities say.

May 25

Sierra Leone health authorities confirm their first Ebola case, a youngwoman admitted to a government hospital in Kenema after a miscarriage.

Mid- June

Aninternational research team sequences the genome of the Zaire strain of the Ebola virus. Researchers around theworld begin studying it for clues about howto treat patients or develop drugs.

June 23

Doctors Without Borders says the epidemic is “out of control.” The group says it has reached the limit of what it can do to fight the outbreak. Toll to date:

528 cases, 337 deaths

June 24

The U. S. Centers for Disease Control and Prevention reports that the outbreak appeared to be running out of steam in Liberia and Guinea in late April, only to resurge in late May and spread to Sierra Leone.

July 20

Liberian American Patrick Sawyer ignores the advice of medical officials and flies from Monrovia, Liberia, to Lagos, spreading Ebola to Nigeria. He dies five days later, and the virus goes on to sicken19 and kill eight, the WHO says.

Aug. 1

Reviving a practice common during the medieval Black Death, the leaders of Guinea, Liberia and Sierra Leone announce plans to set up a cordon sanitaire. Troops are deployed to seal off the area where the three countries meet, a region that accounts for about 70% of the Ebola cases so far.

Aug. 2

Dr. Kent Brantly, a 33- yearold American who contracted Ebola while working in Liberia, is taken to Emory University Hospital in Atlanta. He becomes the first patient with Ebola to be treated on U. S. soil.

1,323 cases, 729 deaths Aug. 5 Nancy Writebol, a 59- yearold American missionary who contracted the virus while working in Liberia, arrives at Emory University Hospital. Both Writebol and Brantly make full recoveries after being treated with the experimental drug ZMapp, though it is unclear whether the drug was helpful. Aug. 8 The WHO Emergency Committee declares a Public Health Emergency of International Concern, saying the Ebola outbreak in West Africa constitutes a public health risk to other states and requires a coordinated international response. 1,779 cases, 961deaths Aug. 12 A WHO panel sanctions the use of experimental drugs to fight the epidemic, though supplies are extremely limited. Aug. 20 A 21-year- oldman who was being monitored by health authorities in Guinea flees to Dakar in neighboring Senegal, becoming that country’s first and only Ebola case. Heis released froma hospital Sept. 19. Aug. 20 Clashes erupt as security forces seal off a Monrovia slum after residents attacked an Ebola screening center. The residents chased away sick patients and removed bloody sheets. Aug. 22 The WHO acknowledges that its Ebola counts underestimate the true number of cases. It cites the existence of “shadow zones,” or small villages where outbreak rumors can’t be investigated because of public resistance or lack of staff or vehicles. 2,615 cases, 1,427 deaths Aug. 28 The WHO warns that the Ebola outbreak is accelerating and could infect more than 20,000 people before it is brought under control. The National Institute of Allergy and Infectious Diseases says it will begin human tests of a vaccine developed by the U. S. military and Glaxo Smith Kline. Sept. 2 The National Institutes of Health unveils a plan to speed development and regulatory approval of the experimental drug ZMapp. Sept. 5 The WHO endorses the use of blood transfusions from recovered patients to boost antibodies for the sick. American aidworker Dr. Rick Sacra is taken to the University of Nebraska Medical Center after contracting Ebola in Liberia. He will make a full recovery after receiving experimental treatments, including blood plasma transfusions from Brantly and the drug TKM Ebola. Sept. 9 Another patient with Ebola is admitted to Emory University Hospital. No details are released. Sept. 16 President Obama says he is sending up to 3,000 military personnel to West Africa, where they will set up17 treatment centers and train healthcare providers. Sept. 16 A team dispatched by the Guinean government to educate people about Ebola is attacked with clubs and stones in the village of Womme. Eight officials and journalists are killed. Sept. 18 The U. N. Security Council declares the Ebola crisis in West Africa a threat to international peace and security. Sept. 19 Sierra Leone begins a nationwide lock down to identify and count cases of Ebola. The country’s residents are required to stay home for three days while health care workers and volunteers go door to door searching for Ebola victims and distributing information about the virus. Sept. 24 U. N. Secretary- General Ban Ki- moon calls for a “twentyfold surge in care, tracking, transport and equipment” to curb the epidemic, which is doubling in size about every threeweeks. Oct. 2 NBC says a freelance cameraman in Liberia has contracted the virus and will be flown back to the U. S. for treatment. Reporting by Alexandra Zavis and MonteMorin