Liberia has suspended senatorial elections due next week as the country grapples with an accelerating Ebola outbreak that health officials have said poses the biggest public health challenge since the Aids epidemic of the 1980s.

At least two million voters, roughly half of the west African nation’s population, were due to elect half of the 30-member upper chamber next Tuesday, but organisers said a “mass movement, deployment and gathering of people” would endanger lives.

Restricted numbers of polling staff and low voter turnout would make it impossible to conduct a credible election, the election commission said.

The commission’s chairman, Jerome George Korkoya, said transporting and distributing equipment including ballot papers and polling kits had been hampered as international airlines had suspended flights in the wake of the outbreak.

“The timely delivery of these materials, most of which are sensitive, cannot be guaranteed in the wake of the current wave of the suspension of flights to Liberia,” he said, adding that a new date would be set, before the end of the year if possible.

President Ellen Johnson Sirleaf’s popularity has taken a battering at home over her handling of the Ebola outbreak. Liberia has recorded 2,200 deaths, more than half of the 3,865 total so far.

A presidential request for sweeping emergency powers led to one newspaper running the headline “Flirting with dictatorship” on Thursday. Police used batons and whips to disperse around 100 protesters who had gathered outside the national assembly as politicians debated the request to extend the president’s powers beyond the state of emergency declared in August.

On Thursday, Johnson Sirleaf addressed an International Monetary Fund meeting alongside her counterparts from Guinea and Sierra Leone. All three called for a greater international response to help stem the epidemic. “Our people are dying,” Sierra Leone’s president, Ernest Bai Koroma, said by video link.

Tom Frieden, director the US Centre for Diseases Control and Prevention, told the meeting: “I have been in public health service for 30 years and the only thing I have seen like this is Aids. We will have to work hard to stop it being the next Aids.”

A recent surge of international aid is intended to provide the 2,000-odd beds that are urgently needed. But efforts to recruit medics have been complicated as many local health workers have succumbed to the disease.

On Thursday a Uganda-born doctor died at a treatment centre on the outskirts of the Liberian capital, Monrovia. He was the fourth doctor to die in the country since the start of the outbreak. A handful of international doctors have also been infected.

Experts say many cases are going unreported. The largest number of infections in the past 21 days – a useful measure as it is the longest incubation period of the virus – have come from Sierra Leone. At least 924 cases have been confirmed.

The rise has been concentrated in the west of the country, including the capital, Freetown, which previously was largely spared. “We can’t explain exactly why the numbers have gone up in the western area, but we’re going to discuss how to tackle it,” said Brima Kargbo, the chief medical officer.

Sierra Leone has 304 beds, which is well short of the 1,100-odd the WHO estimates it needs. Two burial teams in the western area went on strike this week over delayed payment. One worker, who spoke on condition of anonymity, said: “We’re risking our lives and we’re not being paid for it. And since we started this work, people have been talking a lot – we’re not welcome in our community any more.”

There is one bright spot: new cases have all but stopped in the eastern region bordering Guinea and Liberia, where the transmissions started and were initially highest. Health campaigns and treatment centres are clustered there, and some districts are now going days without reporting any new cases.