| Cyclosporiasis | |
|---|---|
| Other names | cyclosporosis |
 | |
| Cyclospora cayetanensis | |
| Specialty | Infectious disease |
Cyclosporiasis is a disease caused by infection with Cyclospora cayetanensis , a pathogenic apicomplexan protozoan transmitted by feces or feces-contaminated food and water. [1] Outbreaks have been reported due to contaminated fruits and vegetables. It is not spread from person to person, but can be a hazard for travelers as a cause of diarrhea.
Cyclosporiasis primarily affects humans and other primates. When an oocyst of Cyclospora cayetanensis enters the small intestine, it invades the mucosa, where it incubates for about one week. After incubation, the infected person begins to experience severe watery diarrhea, bloating, fever, stomach cramps, and muscle aches.[ citation needed ]
The parasite particularly affects the jejunum of the small intestine. Of nine patients in Nepal who were diagnosed with cyclosporiasis, all had inflammation of the lamina propria along with an increase of plasma in the lamina propria. Oocysts were also observed in duodenal aspirates. [2]
Oocysts are often present in the environment as a result of using contaminated water or human feces as fertilizer.
Diagnosis can be difficult due to the lack of recognizable oocysts in the feces. PCR-based DNA tests and acid-fast staining can help with identification.[ citation needed ]
There is no vaccine to prevent cyclosporiasis in humans at present, but one is available for reduction of fetal losses in sheep.[ citation needed ]
The infection is often treated with trimethoprim/sulfamethoxazole, also known as Bactrim or co-trimoxazole, because traditional anti-protozoal drugs are not sufficient. To prevent transmission, food should be cooked thoroughly and drinking water from streams should be avoided.
The first recorded cases of cyclosporiasis in humans were as recent as 1977, 1978, and 1979. They were reported by Ashford, a British parasitologist who discovered three cases while working in Papua New Guinea. Ashford found that the parasite had very late sporulation, from 8–11 days, making the illness difficult to diagnose. When examining feces, the unsporulated oocysts can easily be mistaken for fungal spores, and thus can be easily overlooked. [3]
In 2007, Indian researchers published a case report that found an association between Cyclospora infection and Bell's palsy. This was the first reported case of Bell's palsy following chronic Cyclospora infection. [4] In addition to other extra-intestinal reports, cyclosporiasis might be involved in either reversible neuronal damage or other unknown mechanisms to lead to Guillain-Barré syndrome or Bell's palsy.
In 2010, a report of Cyclospora transmission via swimming in the Kathmandu Valley was published in the Journal of Institute of Medicine. [5] The researchers found that openly defecated human stool samples around the swimmer's living quarters and near the swimming pool were positive for Cyclospora. However, they did not find the parasite in dog stool, bird stool, cattle dung, vegetable samples, or water samples. They concluded that pool water contaminated via environmental pollution might have caused the infection, as the parasite can resist chlorination in water. [6]
Cyclosporiasis infections have been well reported in Nepal. In one study, Tirth Raj Ghimire, Purna Nath Mishra, and Jeevan Bahadur Sherchan collected samples of vegetables, sewage, and water from ponds, rivers, wells, and municipal taps in the Kathmandu Valley from 2002 to 2004. [7] They found Cyclospora in radish, cauliflower, cabbage, and mustard leaves, as well as sewage and river water. This first epidemiological study determined the seasonal character of cyclosporiasis outbreaks in Nepal during the rainy season, from May to September. [8]
At the beginning of the AIDS epidemic in the early 1980s, cyclosporiasis was identified as one of the most important opportunistic infections among AIDS patients. [9]
In 2005, Ghimire and Mishra reported a case of cyclosporiasis in a patient with low hemoglobin and suggested that this coccidian might be involved in reducing hemoglobin due to lack of immune system. [10] In 2006, their groups published a paper about the role of cyclosporiasis in HIV/AIDS patients and non-HIV/AIDS patients in the Kathmandu Valley. [11]
In 2008, Indian researchers published a report about the epidemiology of Cyclospora in HIV/AIDS patients in Kathmandu. [12] They examined samples of soil, river water, sewage, chicken stool, dog stool, and stool in the streets, and found them positive for Cyclospora. They also evaluated several risk factors for cyclosporiasis in AIDS patients. [12]
Although it was initially thought that Cyclospora was confined to tropical and subtropical regions, occurrences of cyclosporiasis are becoming more frequent in North America. According to the Centers for Disease Control and Prevention, there have been 11 documented cyclosporiasis outbreaks in the U.S. and Canada since the 1990s. The CDC also recorded 1,110 laboratory-confirmed sporadic instances of cyclosporiasis. [13]
Between June and August 2013, multiple independent outbreaks of the disease in the U.S. sickened at least 631 people across 25 states. [14] [15] Investigations later identified a bagged salad mixture as the cause of an outbreak in Iowa and Nebraska. [16]
In 2015, the CDC was notified of 546 persons with confirmed cyclosporiasis infection across 31 states. Cluster investigations in Texas, where the greatest number of infections was reported, indicated that contaminated cilantro was the culprit. [17]
During July 21–August 8, 2017, the Texas Department of State Health Services (DSHS) was notified of 20 cases of cyclosporiasis among persons who dined at a Mediterranean-style restaurant chain (chain A) in the Houston area. [18]
On July 31, 2018, the United States Department of Agriculture (USDA) issued a public health alert for certain beef, pork and poultry salad and wrap products potentially contaminated with Cyclospora. [19] The contamination came from the chopped romaine lettuce used in these products.
In June 2020, the CDC and other regulatory bodies began investigating an outbreak of Cyclosporiasis in the Midwestern United States linked to bagged salad mix. [20] On June 27, 2020, Fresh Express announced a voluntary recall of over 91 Fresh Express and private label salad products. [21]
Trichuriasis, also known as whipworm infection, is an infection by the parasitic worm Trichuris trichiura (whipworm). If infection is only with a few worms, there are often no symptoms. In those who are infected with many worms, there may be abdominal pain, fatigue and diarrhea. The diarrhea sometimes contains blood. Infections in children may cause poor intellectual and physical development. Low red blood cell levels may occur due to loss of blood.
Cryptosporidiosis, sometimes informally called crypto, is a parasitic disease caused by Cryptosporidium, a genus of protozoan parasites in the phylum Apicomplexa. It affects the distal small intestine and can affect the respiratory tract in both immunocompetent and immunocompromised individuals, resulting in watery diarrhea with or without an unexplained cough. In immunosuppressed individuals, the symptoms are particularly severe and can be fatal. It is primarily spread through the fecal-oral route, often through contaminated water; recent evidence suggests that it can also be transmitted via fomites contaminated with respiratory secretions.
Isosporiasis, also known as cystoisosporiasis, is a human intestinal disease caused by the parasite Cystoisospora belli. It is found worldwide, especially in tropical and subtropical areas. Infection often occurs in immuno-compromised individuals, notably AIDS patients, and outbreaks have been reported in institutionalized groups in the United States. The first documented case was in 1915. It is usually spread indirectly, normally through contaminated food or water (CDC.gov).
The fecal–oral route describes a particular route of transmission of a disease wherein pathogens in fecal particles pass from one person to the mouth of another person. Main causes of fecal–oral disease transmission include lack of adequate sanitation, and poor hygiene practices. If soil or water bodies are polluted with fecal material, humans can be infected with waterborne diseases or soil-transmitted diseases. Fecal contamination of food is another form of fecal-oral transmission. Washing hands properly after changing a baby's diaper or after performing anal hygiene can prevent foodborne illness from spreading.
Campylobacteriosis is among the most common infections caused by a bacteria in humans, often as a foodborne illness. It is caused by the Campylobacter bacterium, most commonly C. jejuni. It produces an inflammatory, sometimes bloody, diarrhea or dysentery syndrome, and usually cramps, fever and pain.
Travelers' diarrhea (TD) is a stomach and intestinal infection. TD is defined as the passage of unformed stool while traveling. It may be accompanied by abdominal cramps, nausea, fever, headache and bloating. Occasionally bloody diarrhea may occur. Most travelers recover within three to four days with little or no treatment. About 12% of people may have symptoms for a week.
Coccidia (Coccidiasina) are a subclass of microscopic, spore-forming, single-celled obligate intracellular parasites belonging to the apicomplexan class Conoidasida. As obligate intracellular parasites, they must live and reproduce within an animal cell. Coccidian parasites infect the intestinal tracts of animals, and are the largest group of apicomplexan protozoa.
AIDS-defining clinical conditions is the list of diseases published by the Centers for Disease Control and Prevention (CDC) that are associated with AIDS and used worldwide as a guideline for AIDS diagnosis. CDC exclusively uses the term AIDS-defining clinical conditions, but the other terms remain in common use.
Cryptosporidium parvum is one of several species that cause cryptosporidiosis, a parasitic disease of the mammalian intestinal tract.
Cryptosporidium, sometimes called crypto, is an apicomplexan genus of alveolates which are parasites that can cause a respiratory and gastrointestinal illness (cryptosporidiosis) that primarily involves watery diarrhea, sometimes with a persistent cough.
Balantidiasis is a protozoan infection caused by infection with Balantidium coli.
Cyclospora cayetanensis is a coccidian parasite that causes a diarrheal disease called cyclosporiasis in humans and possibly in other primates. Originally reported as a novel pathogen of probable coccidian nature in the 1980s and described in the early 1990s, it was virtually unknown in developed countries until awareness increased due to several outbreaks linked with fecally contaminated imported produce. C. cayetanensis has since emerged as an endemic cause of diarrheal disease in tropical countries and a cause of traveler's diarrhea and food-borne infections in developed nations. This species was placed in the genus Cyclospora because of the spherical shape of its sporocysts. The specific name refers to the Cayetano Heredia University in Lima, Peru, where early epidemiological and taxonomic work was done.
The 1993 Milwaukee cryptosporidiosis outbreak was a significant distribution of the Cryptosporidium protozoan in Milwaukee, Wisconsin, and the largest waterborne disease outbreak in documented United States history. It is suspected that The Howard Avenue Water Purification Plant, one of two water treatment plants in Milwaukee at the time, was contaminated. It is believed that the contamination was due to an ineffective filtration process. Approximately 403,000 residents were affected resulting in illness and hospitalization. Immediate repairs were made to the treatment facilities along with continued infrastructure upgrades during the 25 years since the outbreak. The total cost of the outbreak, in productivity loss and medical expenses, was $96 million. At least 69 people died as a result of the outbreak. The city of Milwaukee has spent upwards to $510 million in repairs, upgrades, and outreach to citizens.
The discovery of disease-causing pathogens is an important activity in the field of medical science. Many viruses, bacteria, protozoa, fungi, helminthes and prions are identified as a confirmed or potential pathogen. In the United States, a Centers for Disease Control program, begun in 1995, identified over a hundred patients with life-threatening illnesses that were considered to be of an infectious cause, but that could not be linked to a known pathogen. The association of pathogens with disease can be a complex and controversial process, in some cases requiring decades or even centuries to achieve.
Blastocystosis refers to a medical condition caused by infection with Blastocystis. Blastocystis is a protozoal, single-celled parasite that inhabits the gastrointestinal tracts of humans and other animals. Many different types of Blastocystis exist, and they can infect humans, farm animals, birds, rodents, amphibians, reptiles, fish, and even cockroaches. Blastocystosis has been found to be a possible risk factor for development of irritable bowel syndrome.
Cryptosporidium hominis, along with Cryptosporidium parvum, is among the medically important Cryptosporidium species. It is an obligate parasite of humans that can colonize the gastrointestinal tract resulting in the gastroenteritis and diarrhea characteristic of cryptosporidiosis. Unlike C. parvum, which has a rather broad host range, C. hominis is almost exclusively a parasite of humans. As a result, C. hominis has a low zoonotic potential compared to C. parvum. It is spread through the fecal-oral route usually by drinking water contaminated with oocyst laden feces. There are many exposure risks that people can encounter in affected areas of the world. Cryptosporidium infections are large contributors of child death and illness in heavily affected areas, yet low importance has been placed on both identifying the species and finding more treatment options outside of nitazoxanide for children and AIDS patients.
Protozoan infections are parasitic diseases caused by organisms formerly classified in the kingdom Protozoa. They are usually contracted by either an insect vector or by contact with an infected substance or surface and include organisms that are now classified in the supergroups Excavata, Amoebozoa, SAR, and Archaeplastida.
Gunjanagar is a town in Bharatpur, Chitwan in Bagmati Province of southern Nepal. The former Gunjanagar VDC and Saradanagar VDC were merged on 18 May 2014 to form new Chitrawan Municipality, which later was merged with Bharatpur. At the time of the 1991 Nepal census it had a population of 11,076 people living in 2025 individual households.
Amoebiasis, or amoebic dysentery, is an infection of the intestines caused by a parasitic amoeba Entamoeba histolytica. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include lethargy, loss of weight, colonic ulcerations, abdominal pain, diarrhea, or bloody diarrhea. Complications can include inflammation and ulceration of the colon with tissue death or perforation, which may result in peritonitis. Anemia may develop due to prolonged gastric bleeding.
Cystoisospora belli, previously known as Isospora belli, is a parasite that causes an intestinal disease known as cystoisosporiasis. This protozoan parasite is opportunistic in immune suppressed human hosts. It primarily exists in the epithelial cells of the small intestine, and develops in the cell cytoplasm. The distribution of this coccidian parasite is cosmopolitan, but is mainly found in tropical and subtropical areas of the world such as the Caribbean, Central and S. America, India, Africa, and S.E. Asia. In the U.S., it is usually associated with HIV infection and institutional living.
