The first Ebola patient in the largest city in the east of the Democratic Republic of the Congo has died, authorities have said.

The spread of the virus to Goma, a city of roughly 1 million people and a regional transport hub, has raised fears the outbreak, already the second deadliest ever Ebola epidemic, could spread more widely.

Q&A What is Ebola? Show Hide Ebola virus disease (EVD) first appeared in 1976 in two outbreaks, located in what is now known as South Sudan and the Democratic Republic of Congo. The latter outbreak was in a village near the Ebola River, giving the disease its name. Ebola causes fever, aches and diarrhoea and attacks the immune system, causing blood clotting cells to malfunction so that victims bleed extensively and die if their immune system cannot fight off the viral infection. It is spread from person to person through body fluids. Infected patients are isolated and treated by medical teams wearing full protective body suits who try to boost their immune response. The average case fatality rate is around 50% - and health-care workers have frequently been infected. Burial ceremonies involving direct contact with the body of the deceased can also contribute to transmission. A vaccine, still experimental, has proven to be highly effective in preventing the disease, according to the World Health Organization.

The patient was a priest who became infected during a visit to the town of Butembo, one of the epicentres of the outbreak, before taking a bus to Goma, Congolese officials have said.

He was being driven from Goma to a clinic in Butembo on Monday to receive treatment when he died, North Kivu province’s governor, Carly Nzanzu, said.

The World Health Organization said on Monday health officials had identified 60 people who had come into contact with the pastor since he was taken ill and half of them had been vaccinated.

Goma, more than 220 miles south of where the Ebola outbreak was first detected a year ago, is the largest city to be affected by the outbreak. Many of the region’s usable roads pass through Goma and it is a focus of air and water transport.

According to the latest government statistics, the disease continues to spread and has infected more than 2,500 people. Nearly 1,700 have died, while 700 recovered.

Three Ebola cases that originated in Congo were confirmed in neighbouring Uganda a month ago, but no new cases have since been registered there.

Rwandan authorities have called for calm. Diane Gashumba, the health minister, said 2,600 health workers had been vaccinated. “This Ebola epidemic has now reached close to Rwanda. There is a need to be more vigilant and to avoid unnecessary visits to Goma,” she said.

The pastor became ill last week in Butembo but decided to travel to Goma, North Kivu province, on Sunday. While in Butembo, the 46-year-old held regular services in seven churches, during which he laid his hands on worshippers, including people who were ill, the health ministry said.

Officials called on communities to take precautions such as washing their hands and avoiding physical contact with anyone suspected of being contaminated with the virus.

The number of people moving around or through the zone worst hit by Ebola has been a big challenge for health services. Attacks against health workers and treatment facilities have also been a problem. On Monday, two Ebola awareness workers were killed in the affected zone.

Eastern DRC is home to a variety of armed groups, and Mai-Mai militia fighters are active near the hardest-hit towns. Health teams have been unable to access areas affected by violence to vaccinate people at risk of infection and to bring infected patients into isolation.

Quick guide Ebola in the Democratic Republic of the Congo Show Hide How bad is the current outbreak? With more than 2,577 confirmed cases and more than 1,803 confirmed deaths, the outbreak in the eastern DRC is the second largest in history. It has a 67% fatality rate and 11 months after it began, the case numbers are still escalating. It is disproportionately affecting women (55% of cases) and children (28%). The WHO declared the outbreak an international public health emergency in July 2019. The same month saw the the first diagnosis of a case in Goma, a city of 2 million people, which is a transport hub on the border with Rwanda. In early August Rwanda announced that it was closing its border with DRC. The WHO has long said that the national and regional risk levels are very high and containment of the spread to North Kivu and Ituri provinces was unlikely, unless a break in the fighting made it safe for health workers. What is Ebola and how do you treat it? Ebola hemorrhagic fever is caused by a virus that has a reservoir among forest animals, including monkeys and bats. It is spread through body fluids, which is why carers – mostly female relatives and nursing staff – are particularly at risk. It causes fever, aches and diarrhoea and attacks the immune system, causing blood clotting cells to malfunction so that victims bleed extensively and die if their immune system cannot fight off the viral infection. Drugs are still experimental. Patients are isolated and treated by nurses wearing full protective body suits and masks who try to boost their immune response. Friends and relatives are quarantined for 21 days. Prevention measures include washing hands at every opportunity and safe burial practices, with no touching or washing of the body, as is traditional in some cultures. How does this compare with other outbreaks? The 2013 and 2016 outbreak in Sierra Leone, Liberia and Guinea spread for months through forest regions in west Africa where Ebola was unknown before the emergency was recognised. It escalated when it emerged in towns and cities, with 28,600 cases and 11,300 deaths. DRC successfully stamped out nine previous Ebola outbreaks in rural areas within a matter of a few months. Aid agencies, infectious disease experts and the WHO say it will be very hard to bring this outbreak under control, even though they have had vaccines and experimental drugs from the outset. What are the contributing factors to this outbreak? There is almost no functioning state in much of eastern DRC. There is an almost total lack of basic services such as power, education, roads, healthcare, and the authority of the government only extends to the edges of urban areas. Police are corrupt, predatory and violent. In rural zones, militia and armed bands provide security and employment opportunities but also steal, rape and kill at will. It is one of the most hostile environments faced by aid and health workers anywhere in the world. Mistrust of officials and foreigners is harming efforts to tackle the disease and conspiracy theories are rampant. Some believe the outbreak is fake news spread by rapacious NGOs and the UN to justify their presence in the country and allow the extraction of valuable mineral resources. Sarah Boseley and Jason Burke

At other times the violence against health teams has come from residents who do not want their loved ones taken to treatment centres or buried in accordance with guidelines aimed at reducing Ebola transmission.

On a visit to the eastern DRC last week, Rory Stewart, the UK’s international development secretary, said the year-long Ebola outbreak was on the edge of spiralling out of control and the World Health Organization should declare it an international emergency.

Additional reporting by Ignatius Ssuuna in Goma