The phrase "a massive outbreak that" is correct and usable in written English.
It can be used when discussing a significant occurrence of a disease or phenomenon that is spreading rapidly.
Example: "The health department issued a warning about a massive outbreak that has affected several communities in the region."
Alternatives: "a large-scale outbreak that" or "a significant outbreak that".
Just 10 months after a devastating earthquake struck the nation's capital in January 2010, Haiti was faced with a massive outbreak of cholera that would cause as many as 1,000 new cases per day and has affected more than 600,000 people.
In the wake of a massive outbreak in Britain that peaked in 1993, the US intensified precautions to keep BSE out of US cattle and the food supply.
Think back to the birth control pill, circa 1960 -- the one that caused a massive outbreak of swollen breasts, bloating and depression and even triggered life-threatening complications like blood clots.
In addition, they shared a common ancestor with a strain that caused a massive outbreak in French Polynesia in November 2013.
PARIS--Scientists are beginning to unravel the causes behind a massive outbreak of a little-known viral disease that's plaguing islands in the Indian Ocean.
Now, 30 years later, we are faced with the threat of an influenza pandemic that might emerge from a massive outbreak of avian influenza H5N1 in Asian chickens.
A massive outbreak of mad cow disease in the United Kingdom that peaked in 1993 was blamed for the deaths of 180,000 cattle and more than 150 people.
Most considered the influenza vaccination programme useful: I think that the influenza vaccination programme helps, that it would so to say help to prevent, well, a massive outbreak.
The wholesale retailer said last week that, despite rising prices on chicken resulting from shortages linked to a massive outbreak of bird flu, the cost of its popular rotisserie chicken would remain at $4.99.
Things have been this way since last June, when the region witnessed a massive outbreak of sectarian violence following the alleged rape and murder of a Rakhine woman and a revenge attack that killed ten Muslims.
