Infected passenger could have spread virus
No one knows for sure just how many people Patrick Sawyer came into contact with the day he boarded a flight in Liberia, had a stopover in Ghana, changed planes in Togo, and then arrived in Nigeria, where authorities say he died days later from Ebola, one of the deadliest diseases known to man.
Now health workers are scrambling to trace those who may have been exposed to Sawyer across West Africa, including fellow passengers.
Health experts say it is unlikely he could have infected others with the virus that can cause victims to bleed from the eyes, mouth and ears. Still, unsettling questions remain: How could a man whose sister recently died from Ebola manage to board a plane leaving the country?
Sawyer's death on Friday has led to tighter screening of airline passengers in west Africa, where an unprecedented outbreak that emerged in March has killed more than 672 people.
"The best thing would be if people did not travel when they were sick, but the problem is people won't say when they're sick. They will lie in order to travel, so it is doubtful travel recommendations would have a big impact," said Dr David Heymann, professor of infectious diseases at the London School of Hygiene and Tropical Medicine.
"The important thing is for countries to be prepared when they get patients infected with Ebola, that they are isolated and health workers take the right steps."
Sawyer was immediately quarantined upon arrival in Lagos and Nigerian authorities say his fellow travelers were advised of Ebola's symptoms and then were allowed to leave.
Health officials rely on "contact tracing" - locating anyone who may have been exposed, and then anyone who may have come into contact with that person. That may prove impossible, given that other passengers journeyed on to dozens of other cities.