What was Operation Sea Spray? Internet draws parallels with chemical fog taking over the globe 

The United States government carried out a project called "Operation Sea Spray" in the mid-20th century. A crew of a U.S. Navy minesweeper ship was authorized to spray the bacterium Serratia marcescens and Bacillus globigii using industrial hoses into the atmosphere two miles off the coast of Northern California.

This six-day-long September 1950 project aimed to assess how big cities like San Francisco would react to a bioweapon terror attack and whether the famous foggy nature of it would help in the spread of the microbe.

Operation Sea Spray is currently trending online amid a mysterious fog taking over the world. Since Christmas 2024, certain parts of the world, including the UK, the USA, and Canada, have been experiencing an unusual and thick fog cover, and people online have been spreading conspiracy theories about it.

Some claim it's alien activity, while others think it is a chemical spillage or bioweapons. Additionally, the term "Fogvid-24" has also gone viral. Inspired by COVID-19, the term refers to exposure to the current fog cover, which has reportedly caused people to fall ill with flu- or cold-like symptoms.

Now, conspiracy theories surrounding Operation Sea Spray have also emerged, with many claiming the fog is related to the 1950 project. Here are some of the comments in this regard from the social networking site X.

“Guys, they dumped a bunch of microbes on the country this week, in the form of fog. I know it sounds tinfoil, but my Spidey senses are telling me they are seeding the skies with pathogens that make us sick. Operation Sea-Spray 4.0 (December 24-31, 2024),” a person wrote.

“@TheRedactedInc MAJOR ALERT. PLEASE PAY ATTENTION TO THIS… THIS IS BAD... drones lure folks outside... Then the fog rolls in!! This is Operation Sea Spray all over again!!!” another person wrote.

“OPERATION SEASPRAY - hydrophilic, bacteria-infused particulates essentially behaving like a fog to spread disease. NB Did you yellow sulphur (Flowers Of Sulphur) is a strong antibacterial agent and sulphur is an essential mineral for your body?” a netizen wrote.

“If anyone says you’re crazy for thinking the government would spray harmful particulates in fog on their own citizens, tell them to look up ‘Operation Sea Spray,’” another wrote.

Many netizens made similar claims, referring to Operation Sea Spray.

“The US has a long record of germ warfare shenanigans, even with American citizens. In 1950, the US Navy sprayed Serratia marcescens into the air near San Francisco. The project, ‘Operation Sea Spray’ aimed to determine the susceptibility of a major city to a bioweapon attack,” a user wrote.

“If you think the government can't manipulate the weather, and that's just a conspiracy theory, look at some of the many patents to do just that. Look up Operation Sea Spray in 1950. We are the experiment,” another user wrote.

“Remember Operation Sea Spray when the government sprayed bacteria over San Francisco and didn't tell anyone, and how 70 years later people are talking about democracy dying and strange drones and fogs? Lol,” an individual wrote.

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All you need to know about Operation Sea Spray amid the latest fog conspiracy theories

According to the Smithsonian Magazine, the United States Navy sprayed the apparently harmless Serratia marcescens into the open air around San Franciso for nearly a week starting from September 26, 1950. The project, which was an aftereffect of the Second World War, was called Operation Sea Spray.

This bacterium thrives in soil and water and is known to produce bright red pigment, making it easy to locate. As a result, it was used in a biowarfare experiment where the U.S. military collected samples from 43 sites to monitor the spread of the bacterium.

Back then, authorities found out that not only San Francisco but also the suburbs were affected by it, meaning approximately 800,000 residents inhaled billions of bacterial spores. The project proved that cities as large as SF could thus be susceptible to bioweapon attacks. Interestingly, the U.S. Navy had no idea that the bacterium had any other effects other than producing red spots on infested food items.

However, a week after Operation Sea Spray was carried out, nearly a dozen people admitted themselves to the Standford University Hospital with urinary tract infections. Experts discovered that the bacterium affected their bodies, and it was reported as the first outbreak of Serratia marcescens, which only became public knowledge in 1976.

While most people survived, a man named Edward Nevin, who underwent prostate surgery, succumbed to the bug, as per the Smithsonian Magazine. Meanwhile, researchers later revealed that the release of the microbe permanently altered San Francisco's ecological system. For instance, iflscience.com has claimed that microbes can cause respiratory tract infection, and SF's rising cases of pneumonia during the 1950 project might have been interconnected.

Notably, the United States military conducted at least 239 similar experiments across the country for the next two decades, including in cities like New York City and Washington D.C. For example, zinc cadmium sulfide, which is now known to cause cancer, was sprayed in the former. At the same time, another location-specific experiment was planned for the Greyhound bus station and airport in the latter.

Biowarfare tests were also done on soldiers and their families who lived on military bases. In addition, the Defense Ministry sprayed Serratia marcescens combined with anthrax simulant and phenol as part of the DICE trials along the coast of Dorset, southern England.

However, U.S. President Richard Nixon prohibited it in 1969.

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The ongoing foggy phenomenon has disrupted flight schedules, train journeys, and road trips of people during the holiday season on both sides of the Atlantic. So far, it remains unclear whether any external factor is responsible and how long it will last.