Guests staying at all inclusive resorts and hotels in the Riviera Maya resort and Cancun in Mexico are reportedly suffering severe sickness and diarrhoea.
This is the fourth time that the resort areas have been hit with a mass sickness outbreak linked to the same bug Cyclospora, which is commonly associated with food and water contaminated with faeces.
In 2016 - 443 UK nationals were confirmed with Cyclospora from the same area and many of them were Scottish.
Bosses at Health Protection Scotland are now warning Scots tourists to be wary of travelling to the region where people have caught the sickness bug.
Their advice suggests the illness is likely linked to tainted food supplied to hotels throughout the resort area which may have been contaminated by faeces.
Guests are believed to have eaten contaminated food in their hotels and later fell ill with severe stomach cramps and diarrhoea.
Health authorities say investigations are being carried out to try and locate the source of the infection.
Nick Harris Head of Travel at Simpson Millar solicitors - who is representing over 350 victims of past and current outbreaks - said: “This is beyond belief.
“I warned TUI and ABTA that British holidaymakers were falling ill with the bug in May when people started contacting me. But they ignored me.
“They should have been warning people travelling to Mexico but seem to put profit before safety. Tour operators are playing Russian roulette with their customers lives. We are being contacted by many affected holidaymakers and I am genuinely concerned that someone will die before the problem is treated seriously.
“I would urge anyone who has been sick like this on holiday to contact their GP and ask for a Cyclospora test. The current number of victims is just the tip of the iceberg and this is now obviously out of control again but should have been avoided or at least people warned before travelling so that they could make an informed choice.”
Victims who have returned to Scotland from the resort have since been diagnosed with Cyclospora.
The sickness bug is spread by infected human faeces contaminating water or food and previous outbreaks have been connected to fresh fruit such as raspberries and salad products such as basil and lettuce.
The resort suffered a similar outbreak of Cyclospora last year when 78 people from across the UK were confirmed with the bug when they returned home.
Health authorities said that the outbreak, which they say began in May, now involves 15 hotel resorts in Mexico.
They said in warning statement posted on their website: “Cases of infection with the diarrhoea causing parasite Cyclospora have continued to be reported by UK holidaymakers returning from Mexico.
“This is the fourth successive year since 2015 that cases of cyclospora infection have been reported in travellers returning from Mexico.
“Where information is known, cases have stayed at several different hotels in the Cancun and Riviera Maya region (mostly on an all-inclusive basis), suggesting the source is again likely to be a foodstuff that has been distributed to hotels throughout the region.
“Infection is transmitted through consumption of contaminated food or water, direct person to person spread does not occur. Foods often implicated in outbreaks include soft fruits like raspberries and salad products such as coriander, basil and lettuce.
“Infection can cause frequent, watery diarrhoea, abdominal cramping, bloating, nausea, flatulence, low-grade fever, loss of appetite and weight.
“All travellers to Mexico are strongly advised to maintain a high standard of food, water and personal hygiene, even if staying in high-end resorts.
“On return from Mexico, if travellers have any symptoms such as those described above they should seek medical attention and inform their GP of their travel history.”
Health Protection Scotland said so far there had been 8 laboratory confirmed cases of illness among Scots during the outbreak but the number of cases is expected to rise.
A spokesperson for Health Protection Scotland added: “ Health Protection Scotland (HPS) is aware of an increase in cases of Cyclospora among travellers who have recently returned to Scotland from Mexico.
“Travellers to Mexico are reminded to maintain good food and water hygiene. If possible, they should choose freshly prepared food that is thoroughly cooked and served piping hot. Avoid foods, such as fresh, uncooked berries or unpeeled fruit, and salad items including herbs, since these are difficult to clean.
“If travellers returning from Mexico have any symptoms of diarrhoeal illness, they should seek medical attention and tell their GP about their travel history”