by Abrar Ahmad Chughtai, Holly Seale, Md Saiful Islam,The Conversation

Credit: Miguel Á. Padriñán from Pexels

The latest Ebola outbreak is showing no signs of slowing.

On April 24, thefirst suspected caseof the rare Bundibugyo strain of Ebola was detected in the Democratic Republic of the Congo (DRC). On May 17, the World Health Organizationdeclared the outbreaka "public health emergency of international concern."

The current Ebola outbreak is thethird-largestin world history, with906 suspected casesand223 deathsin the DRC alone as of May 27.

And it may have spread to other continents. Health authorities are now investigatinga suspected casein Italy, andtwo possible casesin Brazil. All three are believed to be travelers returning from either the DRC or Uganda.One American manwho tested positive for Ebola is currently being treated in Germany.

As concerns grow, theCoalition for Epidemic Preparedness Innovationshas committed more thanA$86 millionin funding to fast-track the development of three potential vaccines, targeting the Bundibugyo strain.

But in the meantime, could this outbreak spread further? And how concerned should we be?

A deadly virus

Ebola is a rare butpotentially fatalvirus that mainly spreads throughdirect contactwith the bodily fluids—such as blood, feces and vomit—of an infected person.

Early symptomsof Ebola include sore throat, headaches, fever, fatigue and body pain. Severe Ebola casescan causeskin rashes, shortness of breath, vomiting, diarrhea, abdominal pain and seizures.

Ebola wasfirst identifiedin humans in 1976. Since then, there have been more than40 outbreaksaround the world, with the majority occurring in African countries.

The current outbreak is the third ever to be caused by the rareBundibugyo strain. The majority of past outbreaks were driven by the more deadly Zaire strain, which killsup to 90%of people compared toup to 34%for Bundibugyo.

What is driving this latest outbreak?

The factors driving this latest outbreakalso contributedto the devastating West African outbreak of 2014–16, where more than11,000 people died.

In both outbreaks, the virus had been circulating for months before an outbreak was declared, and initial cases hadnon-specific symptoms.

Both outbreaks also rapidly spread inurban areas. Transmission inhealth-care settingsis another common factor.

Political instability and social unrest also contributed to both outbreaks. Most recently in the DRC, crowds haveset fireto hospital tents, prompting some patients to flee isolation wards.

And certain cultural practices—including traditional burial rituals that often involve handling dead bodies—may haveaccelerated the spreadof both outbreaks.

How it crossed continents

Similar to the West African outbreak, this latestEbola outbreakhas spread to other continents through travel.

Nine casesandone deathhave already been reported in Uganda, which shares a border with the DRC.

AnAmerican manwho tested positive for Ebola while working in the DRC, is in a stable condition after being treated in Germany.

In Italy, authoritiesare monitoringa traveler who recently returned from the DRC to the city of Cagliari.

According to some reports, Brazilian authoritiesare investigatingtwo suspected Ebola cases. They are believed to be two travelers, one who returned from the DRC to São Paulo and the other from Uganda to Rio de Janeiro.

Importantly, both suspected cases have been diagnosed withother illnesses. The São Paulo patient presented with fever and was later diagnosed with severe meningitis. The Rio de Janeiro patient tested positive for malaria after developing a cough, chills and diarrhea, but has sincetested negativefor Ebola.

So for now, no Ebola cases have been confirmed in Brazil. But these suspected cases have prompted the country to activate its Ebola safety protocols, including patient isolation, laboratory testing, and epidemiological investigations.

Meanwhile, several countries have imposed travel restrictions to prevent Ebola from reaching their shores.

Both theUnited StatesandCanadaare temporarilyrestricting entryfor travelers from the DRC, Uganda and South Sudan. TheUSand other countries such asIndia and Mexicoare also strengthening public health screening and disease monitoring measures, particularly at airports. Some countries have mandated a 21-day quarantine period for their citizens returning from the DRC.

Could it spread further, including to Australia?

At this stage, the risk of Ebola reaching Australia is very low.

Australia has not put in place any travel or quarantine requirements for affected countries, but federal health minister Mark Butler says authorities are still monitoring the outbreak "very closely."

Based on lessons from past outbreaks, there are three main ways the current Central African outbreak could play out.

Without effective control measures, cases may surge in the coming months.Some modelssuggest that by mid-May, up to 1,000 cases had already occurred in the DRC, compared to official figures of about 900 cases. So the actual number of Ebola cases may be much higher than authorities realize.

In a more favorable scenario, a strengthened public health response could bring this latest outbreak under control. This would be possible with continued support from the international community, the rapid development of vaccines and community engagement.

However, the most realistic outcome is that cases will continue to rise before authorities successfully contain the current outbreak.

Nevertheless, the international community responded much more swiftly to this outbreak, particularly compared to the devastating 2014–16 West African outbreak. That alone may protect us from an outbreak of the same catastrophic scale and cost.

This article is republished fromThe Conversationunder a Creative Commons license. Read theoriginal article.

Key medical concepts Bundibugyo ebolavirus Ebola Vaccines Zaire Ebola Virus Malaria Meningitis