JOHANNESBURG (AP) 鈥� When infectious disease specialist Lucille Blumberg checked her email on the morning of May 1, while the country was celebrating the Labor Day holiday, an urgent message caught her attention.
A U.K.-based colleague had written about a passenger from a cruise ship sailing thousands of miles away in the Atlantic Ocean who had been evacuated and admitted to a Johannesburg hospital with suspected pneumonia. Others aboard the vessel were also sick.
The colleague, who monitors diseases in remote British overseas territories in the South Atlantic Ocean, asked Blumberg to follow up on the passenger, who had been evacuated from the in one of the territories, Ascension Island.
Blumberg and other experts at South Africa鈥檚 National Institute for Communicable Diseases were suddenly thrown into the race to identify the cause of an outbreak aboard the Dutch cruise ship MV Hondius.
鈥淓ven though it was a public holiday, we moved, we moved really fast,” Blumberg told The Associated Press. “It was busy. There were many conversations. There were online discussions, and there was laboratory testing happening at the time.鈥�
Within 24 hours, they had determined that the man鈥檚 illness was caused by , a rare rodent-borne virus.
A process of elimination to identify the disease
The elderly British man had arrived at a private hospital in Johannesburg days earlier and was seriously ill, but health workers weren鈥檛 sure of the underlying cause.
By the time he was evacuated from the ship, two elderly Dutch passengers who had been on board the had already died, but there had been little alarm. Ascension Island health authorities had reported a cluster of illnesses on the ship that appeared to be pneumonia to the .
At first, Blumberg and her colleagues thought it might be Legionella, a bacterium that causes a serious form of pneumonia, . Or maybe .
“I called my infectious disease colleagues, and we had a caucus, and we discussed the usual ones,鈥� Blumberg said. 鈥淟egionella is well described in outbreaks in hotels and on cruise ships, and influenza certainly is. These people had visited islands where avian influenza is well documented.鈥�
Tests on all those were negative. The experts also ran an extensive panel of tests for other respiratory diseases. Also, all negative.
The team then began looking more closely at from 鈥� 鈥� and the fact that passengers on board were avid and had reportedly been to parts of South America where there were birds, but also rodents.
Collaboration with experts in South America and the US
That pushed the South African disease experts toward another theory: the rare, rodent-borne infection, which is found in parts of South America.
鈥淚t鈥檚 a well-described, not common, but it鈥檚 a well-described virus in Chile and Argentina,鈥� Blumberg said. She added that their work was aided by collaboration with hantavirus experts from South America and the United States, facilitated by the WHO, the U.N. health agency.
鈥淵ou can get onto a Zoom (call) online and ask your questions and get advice. This is not something every day. So that was quite extraordinary,鈥� Blumberg said.
By then, it was Saturday morning. Blumberg called the head of the only laboratory in South Africa that can test for hantavirus.
鈥淚 said, we want to do hanta, and she said, 鈥榶eah, I鈥檓 coming.’鈥�
The tests, carried out on the sick man’s blood samples, came back positive for hantavirus that afternoon. The team did a second set of tests to be sure, Blumberg said.
Finally, there was a 鈥榳ow moment’
Those positive tests, which also identified the Andes strain of hantavirus, allowed the WHO to inform the cruise ship what it was dealing with and announce an . While hantavirus is not easily spread from person to person, the WHO says the Andes virus can be transmitted between people.
The test results also led Blumberg to rush to collect blood samples from a Dutch woman 鈥� one of the first two cruise passengers to die 鈥� who had disembarked from the ship with her husband’s body on the island of St. Helena and flown to South Africa, where she died.
A posthumous hantavirus test on her was also positive.
鈥淚t was a bit of a wow moment,鈥� Blumberg said. 鈥淎nd at least once you know what you鈥檙e dealing with, it鈥檚 much easier to respond.鈥�
The British man who was the first confirmed case of hantavirus infection from the cruise ship is improving in hospital, South Africa’s health ministry has said. Meanwhile, the ship has at the Dutch port of Rotterdam, where it was disinfected, and the remaining crew members disembarked.
鈥淚鈥檝e been doing outbreaks for 25 years. That鈥檚 what we do. We do them every day,” she said. “I think the important thing was to respond immediately to a question that clearly was urgent and then to take it from there.鈥�
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