A huge decline in Cyclospora infections has been reported in Scotland in 2018 compared with previous years.

​A total of 12 laboratory reports of Cyclospora were received by Health Protection Scotland (HPS) in 2018, compared with 46 in 2017, 167 in 2016, and 24 in 2015.

The increase from 2015 to 2017 was associated with outbreaks among travelers returning from Mexico during the summer months.

Past problem
In the past four years there have been seasonal outbreaks of Cyclospora in people returning to the United Kingdom from Mexico. Annual patient numbers have varied from 79 in 2015, 359 in 2016, 82 in 2017, and 61 in 2018. Most people stayed in the Riviera Maya and Cancun regions of Mexico. The source of infection was suspected to be contaminated food supplied to hotels throughout the area.

As of early June this year, nine Cyclospora cases in returning holidaymakers had been reported in England. Travel destinations included the Dominican Republic, Indonesia and Mexico.

Cyclosporiasis is a diarrheal disease caused by the parasite Cyclospora cayetanensis. Infection develops after consuming contaminated food or drinks. Raw fruit and vegetables such as raspberries, herbs and lettuce imported from or eaten in countries where the parasite is common are associated with infection. It mostly occurs in South America, Central America, South Asia, South East Asia, Middle East and Africa.

Symptoms usually appear about a week after catching the parasite and include diarrhea, nausea, loss of appetite and bloating. They may seem to go away and return more than once and it’s common to feel very tired. If Cyclospora isn’t treated, illness may last from a few days to a month or longer.

​Cryptosporidium climbs
In 2018, HPS received 536 lab reports of Cryptosporidium representing an increase of 27 compared with the 509 reports in 2017. It is within the year-on-year variation observed for the previous 10 years with a range of 430 to 723 cases.

Reports showed two distinct peaks during the year. The first, in the spring, was mainly because of cases of Cryptosporidium parvum while the second peak in the autumn was because of Cryptosporidium hominis and Cryptosporidium parvum.

The rate was slightly higher among females than males. Highest rates were in children younger than five years of age for both males and females. The lowest were among those aged 65 years and older.

Of the 536 reports in 2018, 120 were identified as Cryptosporidium parvum, 54 as Cryptosporidium hominis and two as Cryptosporidium cuniculus. This is a slightly higher proportion of parvum and lower proportion of hominis than in both 2017 and 2016, according to the report.

Cryptosporidiosis is caused by parasites called Cryptosporidium and can be found in water, food, soil or on surfaces or dirty hands contaminated with the feces of humans or animals infected with the parasite. Microscopic amounts of contaminated feces can result in infections.

Symptoms include watery diarrhea, dehydration, nausea, vomiting and fever. They generally begin two to 10 days after becoming infected with the parasite and last for one to two weeks.

Cryptosporidium can be spread by swallowing water, ice, or beverages contaminated with feces from infected humans or animals or eating undercooked food or drinking unpasteurized/raw apple cider or contaminated milk.

Giardia decline
In 2018, HPS received 199 lab reports of Giardia representing a decrease of 70 versus the 269 reports in 2017. It is the first decrease in lab reports following an increasing trend between 2014 and 2017.

Some of the increase in those years was likely because of changes in the diagnostic techniques used in some labs, according to the report.

The rate for males was about 60 percent higher than that for females. The highest rate among males was in those aged 20 to 24 years while the highest for females was in those aged 35 to 39 years.

Giardiasis causes symptoms like diarrhea and bloating. It usually goes away in about a week if treated but can last much longer. People can catch giardiasis in many ways including by drinking water that’s not been treated to kill germs or eating food washed in untreated water or handled by someone with the infection.

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