The uncle’s source of infection is under investigation.

正在对舅舅的感染源进行调查。

youdao

Investigations into the source of infection are underway.

正在进行感染源调查。

youdao

The source of infection for all three cases is still under investigation.

目前仍在对三例病例的感染源进行调查。

youdao

"It is crucial that national authorities do not rush to give information on source of infection which is not proven by bacteriological analysis, as this spreads unjustified fears in the population all over Europe, and creates problems for our food producers selling products in the EU and outside of the EU."

VOA: special.2011.06.10

In Russia, by contrast, injecting heroin with dirty needles is the main source of infection.

ECONOMIST: AIDS

Information available so far points to Farm Rich products as one likely source of infection, the agency said.

WSJ: Rich Products expands Ga. plant frozen food recall

"The most important goal remains to locate the source of infection so that measures to minimise contact can be taken", said Prof Ian Jones, Professor of Virology, University of Reading.

BBC: Threat from novel coronavirus 'remains low'