The worst outbreak of Ebola may have started with a 2-year-old

The worst outbreak of Ebola, which has killed 961 people and triggered
an international public health emergency, may have started with a
2-year-old patient in a village in Guinea.

About eight months ago, the toddler, whom researchers believe may have
been Patient Zero, suffered fever, black stool and vomiting. Just four
days after showing the painful symptoms, the child died on December 6,
2013, according to a report published in The New England Journal of
Medicine.

Scientists don't know exactly how the toddler contracted the virus.
Ebola is spread from animals to humans through infected fluids or
tissue, according to the World Health Organization.

Health workers evacuating the remains of an Ebola Virus Disease victim.

"In Africa, infection has been documented through the handling of
infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope
and porcupines," WHO says, though researchers think fruit bats are
what they call the virus's "natural host."

Researchers who published the paper this year found a chain of
illnesses in the toddler's family.

After the child's death, the mother suffered bleeding symptoms and
died on December 13, according to the report. Then, the toddler's
3-year-old sister died on December 29, with symptoms including fever,
vomiting and black diarrhea. The illness subsequently affected the
toddler's grandmother, who died on January 1, in the family's village
of Meliandou in Guéckédou.

The area in southern Guinea is close to the Sierra Leone and Liberia borders.

The illness spread outside their village after several people attended
the grandmother's funeral.

Funerals tend to bring people in close contact with the body. Ebola
spreads from person to person through contact with organs and bodily
fluids such as blood, saliva, urine and other secretions of infected
people. It has no known cure.

Two of the funeral attendees appeared to bring back the virus to their
village, and it spread to health care workers and other family members
who took care of infected patients.

"A health care worker from Guéckédou with suspected disease, seems to
have triggered the spread of the virus to Macenta, Nzérékoré, and
Kissidougou in February 2014," stated the report, noting that more
Guinea towns were affected.

Clusters of the disease popped up in early 2014 in these areas, with
the initial patients suffering fever, vomiting and severe diarrhea,
according to the report. Hemorrhaging was less frequent, the report
noted.

In early March, the Ministry of Health in Guinea and Doctors Without
Borders in Guinea were notified about the disease clusters.
Health investigators arrived that month and began tracing the disease
by examining hospital documents and conducting interviews with
affected families and villagers.

Ebola has now spread to Liberia, Sierra Leone and Nigeria, prompting
global concerns.

The report about the emergence of Ebola in Guinea was authored by
dozens of international doctors and researchers from institutions in
France, Germany, Guinea, WHO and Doctors Without Borders.