Getty Images photographer John Moore is in Liberia, the country hit hardest by the current Ebola outbreak.

More than 400 people are known to have died of Ebola in Liberia, though the figure may be far higher than that. Some of the hardest-hit areas of the country are under quarantine and many victims are dying uncounted in their own homes, aid workers say.

Many of the sick are still being hidden at home by their relatives, who are too fearful of going to an Ebola treatment centre.

There is no cure or licensed treatment for Ebola and patients often die gruesome deaths with external bleeding from their mouths, eyes or ears.

Because it's spread through direct contact with the bodily fluids of sick patients, Ebola takes an especially harsh toll on doctors and nurses, already in short supply in areas of Africa hit by the disease. Family members have contracted it by caring for their relatives or handling an infected body as part of burial practices.

Outbreaks spark fear and panic. Rumours are rife that Western aid workers are importing Ebola, stealing bodies or even deliberately infecting patients. Winning trust is made harder by a full suit of hood, goggles, mask and gown that hides their faces.

Health workers and clinics have come under attack from residents, who sometimes blame foreign doctors for the deaths. People with Ebola or other illnesses may fear going to a hospital, or may be shunned by friends and neighbours.

The World Health Organisation has said the focus should be on practising good hygiene, and quickly identifying the sick and isolating them. That task is made harder, however, by the shortage of space in treatment facilities.

Beds in such centres are filling up faster than they can be provided, evidence that the outbreak in West Africa is far more severe than the numbers show, said Gregory Hartl, a spokesman for the UN health agency in Geneva.

See more of John Moore's heartbreaking photos of the Ebola outbreak in Liberia here. A third set of photos can be seen here.