(Reuters) – The United States recorded only seven new measles cases last week, the lowest number so far this year, bringing the total for cases to 1,241 in the worst outbreak since 1992, federal health officials said on Monday.

The U.S. Centers for Disease Control and Prevention said it had recorded cases of the highly contagious and sometimes deadly disease in 31 states as of Sept. 5.

The weekly increase is the latest indication that the outbreak is slowing from the dozens of cases reported per week earlier this year.

The disease was declared eliminated in the United States in 2000, meaning there was no continuous transmission of the disease for a year. Still, cases of the virus occur and spread via travelers coming from countries where measles is common.

CDC officials have said the country risks losing its measles elimination status if the outbreak, which began last October in New York state, continues until next month.

Failure to vaccinate poses a public health risk to vulnerable people unable to receive the vaccine, health officials have warned.

(Reporting by Peter Szekley in New York and Tamara Mathias in Bengaluru; Editing by Arun Koyyur and Hugh Lawson)