Contact tracing increases in New York and other states as omicron reaches US


The arrival of the omicron variant of the coronavirus in the United States has prompted health officials in some communities to relaunch contact tracing operations in a bid to slow and better understand its spread as scientists study how it is contagious and if it can thwart vaccines.

In New York City, authorities quickly contacted a man who had tested positive for the variant and who attended an anime conference at a Manhattan convention center last month with more than 50,000 people. Five other participants were also infected with the coronavirus, although officials do not yet know if it was the omicron variant.

“In terms of what we learned about that conference at the Javits Center and those additional cases, our testing and tracing team works immediately with each affected person to determine who else they’ve come into contact with. This contact tracing is absolutely crucial, ”said New York Mayor Bill de Blasio.

Once the global epicenter of the pandemic, New York has the largest contact tracing effort in the country. The city identified four cases of omicron on Thursday, and a fifth was discovered in neighboring Suffolk County on eastern Long Island.

The variant has been detected in a handful of other states so far, including California, Colorado, and Hawaii.

Contact tracers were busy in Nebraska after six cases of omicron were confirmed on Friday. One of the people had recently returned from a visit to Nigeria and the other five were close contacts of that person.

Officials in Philadelphia were working to trace the contacts of a man in his 30s who is the first Pennsylvania resident to be infected with the variant, the city’s Department of Public Health said.

And in Maryland, authorities have rushed to search, quarantine and test close contacts of three people in the Baltimore area who are the first known cases in the state. Two are from the same household, including a vaccinated person who recently traveled to South Africa, and the third has no recent travel history and is unrelated to the other two.

Dr Marcus Plescia, chief medical officer of the Association of State and Territorial Health Officials, said “more and more” contact tracing efforts are expected in the coming days, in part due to uncertainty. about the effectiveness of vaccines and treatments like monoclonal antibodies. be against omicron.

Contact tracing is an essential tool in the response to the pandemic, enabling health services to notify people who have been in close contact with an infected person and to slow the progression of COVID-19.

“Contact tracing can give us information on how it is spreading and hopefully break the chains of transmission to stop clusters and epidemics, or at least delay them until we know more. and understand what our next steps should be, ”said Principal Investigator Crystal Watson. at the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health.

While a lot is still unknown about the variant, early reports are ringing the alarm bells. New cases of COVID-19 in South Africa, which first alerted the world to omicron last week, have risen from around 200 a day in mid-November to more than 16,000 on Friday.

Some of the US cases involve people who had not traveled recently, meaning the variant was probably already circulating in the country in parts of the country.

In New York City, the three-day anime festival in November presents a staff challenge for Tracers due to the large number of attendees. The only known omicron infection involved a man from Minnesota.

Officials have warned of the direct link between the other five coronavirus cases and the event.

“The really important point here is that it’s five cases for a denominator of tens of thousands of people at this conference. And furthermore, we didn’t make any sort of link between these five cases and widespread transmission at the conference, ”said Ted Long, executive director of the NYC Test & Trace Corps, which manages the contact tracing program of the city.

Proof of vaccination was required for admission, as required by city law, and masks were also required.

Officials said they had reached all 36,500 convention attendees, suppliers and exhibitors for whom they had contact information, via email, text or phone call. But they decided that it was not necessary to contact every participant since the infected man did not appear to have close contacts based in New York.

In Minnesota, meanwhile, officials are investigating “a circle of contacts” for the man allegedly infected at the conference, said Kris Ehresmann, the state’s director of infectious diseases.

“Part of the reason we posted where he had been – the anime convention in New York City – is because there were so many people who attended this event. It wouldn’t be possible for him or her. for anyone to identify all of the people they were potentially in contact with, ”Ehresmann said.

Amid the delta variant’s surge, health investigators across the United States became overwhelmed and cut back on contact tracing operations, finding it nearly impossible to keep up with the deluge of new infections, to administer. vaccines and research at the same time.

Many health officials ultimately focused on school exposures or potential super-spraying incidents where large numbers of people were at risk of being exposed.

Dr William Schaffner, professor of infectious diseases at Vanderbilt University School of Medicine, expects this to eventually happen with omicron.

“Tracing and sequencing the contacts will allow us to paint with a wide brush,” Schaffner said. “But we won’t be able to locate it in every case, and at some point, when you know it’s there and it’s spreading, why do we have to? “