On Thursday, the Centers for Disease Control and Prevention said it has identified a strain of West Nile virus that can replicate in the U, U.K., Australia and New Zealand, among other countries.
The agency said it expects to begin issuing orders on Friday to start treating West Nile cases in those countries, but that the U and U. K. could see delays.
The virus was first identified in the northeastern U. S. in 2014 and then spread to the southern U.N. host country, where the outbreak has grown to more than 50,000 cases.
The CDC said Thursday that the strain could spread to more countries if it can’t be contained in the United States.
A study released last week by researchers at the University of Texas School of Public Health showed the strain is less contagious in the developed world than in Africa.
The research showed that while it can cause severe illness in some people, most people who contract the virus are relatively unharmed.