A "boom" of confirmed cases of the coronavirus that has killed almost 3,000 people around the world could already be racing across the U.S. despite ramped-up efforts to contain the outbreak, experts say.
The spread of the virus by "community transmissions is an indication that we could indeed be looking at the tip of the iceberg," Ogbonnaya Omenka, an assistant professor and public health specialist at Butler University's College of Pharmacy and Health Sciences, told USA TODAY on Sunday.
Though fewer than 80 U.S. cases have been confirmed thus far, including a handful in Washington state, a researcher there estimates that " a few hundred" people in the state could actually be infected.
"There are some enormous implications here," Trevor Bedford, a researcher at the Fred Hutchinson Cancer Research Center in Seattle, posted on Twitter. "I believe we're facing an already substantial outbreak in Washington State that was not detected until now."
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Bedford studied two cases that were confirmed weeks apart and determined they were linked through community transmission - from a source not directly connected to another known case. Bedford tweeted his belief that the virus has been spreading undetected, at least in Washington state, for six weeks.
Omenka says that doesn't bode well for efforts to contain the virus nationwide. One of the chief challenges with dealing with community transmission is contact tracing, which may prove difficult because of constant human movements and interactions, Omenka said.
Increased travel and movement of students and families for spring break could also further spread the contagion, he said.
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"Under current circumstances, a boom of cases should be expected," Omenka said. "Especially given the possibility of asymptomatic spread and mildness of the disease."
The way to stop the spread: human behavior. It's crucial that people follow steps recommended by the Centers for Disease Control and Prevention, such as frequently washing their hands and self-quarantining when sick, Omenka said.
The only death in the USA reported thus far was a man in his 50s who had significant underlying health problems, health officials in Seattle said. Omenka said the death confirms the existing trend of the disease being most severe among the most vulnerable members of the population.
The disease began its march across China weeks before reaching the U.S., which gave federal health officials time to prepare, Omenka said.
"Nevertheless, the possibility of a wider spread of the COVID-19 in the U.S. is very likely now, based on recent developments," he said.
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Rhode Island confirms first case
The Rhode Island Department of Health announced the state's first "presumptive positive" case of coronavirus disease. The person is in their 40s and had traveled to Italy in mid-February, the department said in a statement.
The person was being treated in a hospital and "all infection control protocols" were being followed, the statement said.
"We are not seeing widespread community transmission in Rhode Island, and the general level of risk for Rhode Islanders is still low," it added.
World responds to outbreak
Worldwide, the iconic Louvre museum in France shut down Sunday over coronavirus concerns, and the Dominican Republic and Czech Republic reported their first infections in an outbreak that has now spread to more than 60 countries.
Italian authorities announced that the number of people infected doubled to 1,694 in just 24 hours, and five deaths brought the toll there to 34. Australia and Thailand reported their first deaths, the Associated Press said. The global death toll stood at about 3,000, including more than 2,800 in mainland China. More than 88,000 infections have been reported worldwide, the vast majority of them in China.
American Airlines waives change fees
With travelers growing increasingly wary of contracting the virus or having their trips disrupted, American Airlines is seeking to allay some of their concerns.
American announced Sunday afternoon that it would waive change fees for any plane ticket purchased through March 16 as long as the changes were made at least 14 days before the scheduled travel date.
Catholic Church alters practices
The virus is also having an impact on some long-held practices at Catholic Masses.
The archbishop of Paris has told priests to put the Communion bread in worshippers' hands, not in their mouths. In South Carolina, the Diocese of Charleston asked its parishioners to not drink from the Communion cup or shake hands during the sign of peace.
Energy conference in Houston shelved
Organizers of the CERAweek conference that was scheduled to draw thousands of energy executives and officials from 80 nations to Houston was canceled because of coronavirus concerns.
The conference was scheduled for March 9-13. Organizer IHS Markit said it was canceling "with deep disappointment."
"An increasing number of companies are instituting travel bans and restrictions, border health checks are becoming more restrictive," IHS said in a statement. "There is growing concern about large conferences with people coming from different parts of the world."
Contributing: Jorge L. Ortiz, USA TODAY; The Associated Press
This article originally appeared on USA TODAY: Coronavirus: Hundreds may be infected in Washington state