Ebola quarantines in U.S.: Are they warranted?

The release of a nurse who was being held against her will in New Jersey under a new 21-day mandatory quarantine probably won't quell the debate surrounding returning health-care workers who have treatedEbola patients in West Africa.

Kaci Hickox landed at Newark Airport, N.J., on Friday after caring for Ebola patients with Doctors Without Borders (known by its initials in French,MSF), in Sierra Leone. That's the same day the governors of New York and New Jersey ordered the quarantine on anyone arriving in their states who had been in contact with people in West Africa who have Ebola. Hickoxwas the first person quarantined under the policy.

The day before the governors' announcement, and after deploying more than 700 international staff to treat Ebola patients in West Africa, an MSF doctor hadbeen diagnosed with Ebola after returning home to New York City.

MSFsaid Dr. Craig Spencer had followed their protocols and, he posed no public health threat prior to developing symptoms."

Spencer, 33, returned to the U.S. from Guinea, where he had cared for Ebola patients. On the morning of Oct. 23, he had a fever of 100.3 degrees. Later that day, he tested positive for Ebola and that was confirmed the next day. As of Friday afternoon, authorities said he was in stable condition, in isolation at New York's Bellevue Hospital.

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Contact tracing is underway. Spencer's fiance and two friends the only people with whom he had extensive contact since returning are now quarantined. Thatwill continue until 21 days have elapsed since their last contact with Spencer.

Contagiousness low at onset of fever

Both MSF and the U.S. Centers for Disease Control and Prevention require their returningstaff who have treated or been in contact with Ebola patients check their own temperature twice a day. That check will be confirmed by daily phone calls from their local public health department.

Temperature monitoring is critical because fever is the first indication of infection.

Before someone carrying the Ebola virus has a fever or other symptoms, they cannotspread the disease. And the disease is only transmitted through contaminated bodily fluids, such as blood or vomit.

Even when someone with Ebola first exhibits symptoms, they are not especially contagious, tropical disease specialist Dr. Richard Olds tellsCBC News.

When a person develops a viral disease, "in the beginning they have relatively few viral particles in their body or even in their secretions," saysOlds, who isdean of the school of medicine at the University of California, Riverside.

As someone becomes ill, the virus is multiplying in their body. After five or six days, they are highly contagiousif there is a transfer of bodily fluid. "That's a different situation than the situation when a person is asymptomatic, during the incubation period, and even the situation where the person just developed the fever."

Mandatory quarantines in three states

Given the deadliness of the Ebola virus about 70 per cent of patients do not survive an abundance of caution from the first sign of fever is the norm.That's led New York City to implement a thorough contact tracing program.

The New York state and New Jersey quarantine order followed.

On Monday, MSF said in a news release, "Forced quarantine of asymptomatic health workers returning from fighting the Ebola outbreak in West Africa is not grounded on scientific evidence and could undermine efforts to curb the epidemic at its source." MSF expects the quarantine policy will discourage some health workers from going to West Africa to fight Ebola.

Although he also doesn't call for a mandatory quarantine, Olds says that's "not unreasonable." However, "from a public health danger standpoint, I'm not sure that there is sufficient evidence to suggest" a quarantine is needed.

The main reason behind the states' action may be the huge costof contact tracing, he suggests. "The way people are responding to what are probably pretty trivial exposures could get extremely expensive," he says.

On the weekend, Illinois also ordered a 21-day mandatory quarantine. Florida ordered mandatory monitoring.

Meanwhile, preliminary blood tests indicate Hickoxdoes not have Ebola, according to MSF.

Protocols followed

MSF protocols for their returning health-care workers require that they "stay within four hours of a hospital with isolation facilities," and immediately contact the MSF if any relevant symptoms develop.

While Spencer is the first MSF worker to develop Ebola after leaving West Africa, 24 of the group's staff, including threeinternational workers, havecontracted Ebola while in West Africa.Thirteen have died.

"In-depth investigations have so far shown that most of the infections occurred outside MSF's medical facilities in the countries," MSF states in a news release.

MSF says it has sent more than 700 international staff to West Africa, with 270 there now. In total, it has 3,000 employees in West Africa.

The group saysSpencer did everything MSF's protocols call for. As soon as he detected that low-grade fever, "he swiftly notified the MSF office in New York. He did not leave his apartment until paramedics transported him safely to Bellevue Hospital in Manhattan."

MSF guidelines discourage staff from returning to work for 21 days after leaving West Africa.Spencer did not return to his work in international emergency medicine at New York-Presbyterian Hospital and teaching medicine at Columbia University.

MSF staff continue to receive their salaries during the 21-day period.

Contact tracing 'conservative and expensive'

When Thomas Eric Duncan was hospitalized with Ebola in Dallas, extensive contact tracing was carried out and that is happening in New York, too.

Members of Duncan's household were quarantined and "no one in his household, including the woman who cared for him every day" contracted Ebola, New York City Health Commissioner Dr. Mary Bassett told a news conference on Friday.And Duncan had symptoms for at least three days before he was hospitalized.

There is also no record of anyone contracting Ebola while a passenger on the same flight as someone who had Ebola symptoms or later developed Ebola.

Olds says "chasing down everybody is extremely conservative and extremely expensive." He adds that it also "evokes a great deal of concern on the part of the people in the community and quite frankly adds a bit to the hysteria and suggests to the population that they're at some significant risk of coming down with Ebola, and I don'tthink they are, but I understand that that's a reasonable public health response."

He also says it's important to consider that, "probably not since the very early days of AIDS and, historically, probably not since the time of the Black Death in Europe, hasthere been a better example of true physician and nurse heroes that have stepped up, at some significant risk to themselves, to take care of people."

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