The borough has became an area of national intervention for Covid, with 100 new cases since Friday and the infection rate now "three or four times higher" than it was a few weeks ago.
And in the latest health crisis Public Health England (PHE) Midlands, the Health and Safety Executive and Sandwell Council are jointly investigating three laboratory confirmed cases of Legionnaire's and six suspected cases in West Bromwich.
No direct link between the cases has been found, although they are believed to have originated from a "common source".
Eight of the cases were reported to PHE in the last week and a single case reported in July has subsequently been linked to the outbreak. Six of the patients are receiving treatment in hospital.
Dr Adrian Philips, consultant in communicable disease control at PHE Midlands Health Protection Team, said: “While we do not currently have a direct link between these cases, the evidence we have points to the possibility that there is a common source.
"We are taking detailed histories of the movements of the individuals to see if there are similar patterns which would help to identify a common local source of infection.
“Legionnaires’ disease is a rare but potentially life-threatening illness. It is caused by a bacterium commonly associated with water systems and cannot be passed from person to person.
“As a precaution we are working with the Health and Safety Executive and Sandwell Council to identify and control any possible sources of the disease.”
A Sandwell Council spokesman said: "The council is working closely with PHE and the Health and Safety Executive to find the source of this outbreak and we will continue to do everything we can to support the investigation.”
The early symptoms of Legionnaires' disease include 'flu-like' illness with muscle aches, tiredness, headaches, dry cough and fever which can then lead to pneumonia.
Action to date includes identifying, sampling and advising on the disinfection of potential sources of the bacteria, such as cooling towers in areas around West Bromwich that the cases may have each visited. Health care staff, including GPs, have been alerted to look out for others with similar symptoms.
People are advised if they are feeling unwell with any similar unexplained symptoms to Legionnaire's disease to contact their GP, ring NHS 111 or visit www.nhs.uk