It is that time of year again: the air is chilly, your pockets are filled with tissues and every sneeze on the train makes you paranoid you will be next in line to catch a cold. We humans get snotty noses all the time.

But what about our nautical cousins? Whales spend their lives in the water, some of them in the coldest seas on earth. Surely they catch colds?

We asked our readers to share some thoughts on whether whales get colds and snotty blowholes.

"No. A cold is caused by a rhinovirus, and since they don't have noses, catching a cold would be impossible for whales," writes Alan Hall.

Rik Ouwens says something similar. "Probably not, at least not like we do, because 'colds' aren't caused by temperature but by airborne germs. But if a biologist or medical expert knows better, please explain where I'm wrong."

Rik is in luck. We have spoken to some whale experts to find out more.

Cetaceans – the group that includes whales, dolphins and porpoises – can definitely catch diseases, as can all animals.

Occasional spouting is likely to dissipate any mucus that might be ejected from the lungs

"Our research shows many cetaceans stranded on UK shores died from diseases," says Rob Deaville of the Cetacean Strandings Investigation Programme at the Zoological Society of London. "However, 'cold' is a generic term used to describe upper respiratory infections in humans that primarily affect the nose, so the term isn't really relevant to cetaceans."

In other words, whales cannot catch the diseases we call "colds". But might other diseases give whales snotty blowholes?

"No because they live in saltwater," argues Jean Lelliott. "Nothing better than inhaling salty water to sort out your sinuses."

Nettie Hoogwerf Kroos agrees. "When I have a cold I rinse my nose with seawater to keep it clean, so I don't think whales get snotty noses."

It seems this is quite a good point.

"Cetaceans' movement through the water, and occasional spouting is likely to dissipate any mucus that might be ejected from the lungs," says Rob Deaville. "They don't produce mucus in their blowholes like we do in our noses."

I'm not sure whales sneeze as such

It would be a problem if they did. Unlike humans, cetaceans cannot breathe through their mouths, so if they get something stuck in their nostrils they can suffocate. In 2015, Deaville and his colleagues reported that two long-finned pilot whales had suffocated after getting fish stuck in their blowholes.

That said, in August 2016 researchers described a dolphin that was born with a malformed blowhole, and which had learned to breathe through its mouth. But so far this seems to be a one-off.

If whales need to keep their blowholes clear, do they evacuate them by sneezing?

Nath Burg "would like to see that huge blow a whale makes when it has to sneeze".

It might be best to stand back, though, if Ciarán James McGlynn's story is anything to go by. "I was on my first whale watching trip," he writes. "When we were downwind of them a couple of times we got a whiff of their breath! Not a pleasant experience."

Whales do shoot out spouts of water, but this is not the same as sneezing.

The one time I went whale watching I got a cold soon after

"I'm not sure whales sneeze as such," says Ailsa Hall of the University of St Andrews in the UK. "Their regular breaths from their lungs have the capacity to clear their blowhole."

However, they do contract diseases and spread them around. "The gas exchange rate in whale lungs is very rapid, and it is highly likely they transmit disease, particularly morbillivirus, to each other as they surface," says Hall.

Morbilliviruses can result in pneumonia, a lung infection that famously resulted in the death of Keiko, the orca featured in the film Free Willy.

Similarly, Hannah Myers once "cared for a short-finned pilot whale overnight… and had to constantly wash the mucus away from her blowhole." She wonders if this was a case of pneumonia.

If whales can spread airborne diseases, could we catch them?

Barnaby Walker suspects so. "The one time I went whale watching I got a cold soon after. Maybe I caught it from the whale."

It's probably more the case that cetaceans are prone to diseases caused by our activities

While cetaceans may carry "zoonotic" diseases that can be transmitted to humans, we probably do not catch the diseases very often. "Recorded cases are rare," says Deaville.

"Transmission from whales is possible, but for research efforts and to reduce disturbance, people don't tend to get close enough for it to be a problem," says Hall. "Certainly, when dead whales wash ashore and are collected by various researchers for necropsy, then pathogens could be transmitted to humans during this process."

It is more likely that we are making the whales ill. "It's probably more the case that cetaceans are prone to diseases caused by our activities, such as pollution, than the other way round," says Deaville. "Contaminants in the marine environment can cause immunosuppression and potentially lead to death."

In any case, even those researchers who are actively studying whale mucus need not get too close. Paul Durnion reminds us that "there is a drone designed to collect whale snot."

In fact there are now several such drones. One, created by the Ocean Alliance, is affectionately called "SnotBot".

Snotbot can hover quietly and unobtrusively above whales, while collecting mucus from their blow in petri dishes fixed on top of it. These samples can be used to monitor diseases, as well as hormones like cortisol and progesterone that help researchers figure out if a whale is healthy, or even pregnant.

Nevertheless, older methods are still in use. "We currently collect mucus samples from a whale's blow using a collecting device at the end of a long pole on a boat," says Hall.

Join over six million BBC Earth fans by liking us on Facebook, or follow us on Twitter and Instagram.

If you liked this story, sign up for the weekly bbc.com features newsletter called "If You Only Read 5 Things This Week". A handpicked selection of stories from BBC Future, Earth, Culture, Capital and Travel, delivered to your inbox every Friday.