Editing Botulism (section)

== Signs and symptoms ==
The muscle weakness of botulism characteristically starts in the muscles supplied by the [[cranial nerves]]—a group of twelve nerves that control [[eye movement (sensory)|eye movements]], the [[facial muscles]] and the muscles controlling [[chewing]] and [[swallowing]]. [[Diplopia|Double vision]], [[Ptosis (eyelid)|drooping of both eyelids]], loss of facial expression and swallowing problems may therefore occur. In addition to affecting the [[Somatic nervous system|voluntary muscles]], it can also cause [[Dysautonomia|disruptions in the autonomic nervous system]]. This is experienced as [[xerostomia|a dry mouth and throat]] (due to decreased production of saliva), [[postural hypotension]] (decreased blood pressure on standing, with resultant lightheadedness and risk of blackouts), and eventually [[constipation]] (due to decreased [[peristalsis|forward movement of intestinal contents]]).<ref name=Sobel2005/> Some of the toxins (B and E) also precipitate [[nausea]], [[vomiting]],<ref name=Sobel2005/> and [[dysarthria|difficulty with talking]]. The weakness then spreads to the arms (starting in the shoulders and proceeding to the forearms) and legs (again from the thighs down to the feet).<ref name=Sobel2005>{{cite journal | vauthors = Sobel J | title = Botulism | journal = Clinical Infectious Diseases | volume = 41 | issue = 8 | pages = 1167–73 | date = October 2005 | pmid = 16163636 | doi = 10.1086/444507 | doi-access = free }}</ref>

Severe botulism leads to reduced movement of the [[muscles of respiration]], and hence problems with [[gas exchange]]. This may be experienced as [[dyspnea]] (difficulty breathing), but when severe can lead to [[respiratory failure]], due to the buildup of unexhaled [[hypercapnia|carbon dioxide]] and its resultant depressant effect on the brain. This may lead to respiratory compromise and death if untreated.<ref name=Sobel2005/>

Clinicians frequently think of the symptoms of botulism in terms of a classic triad: [[bulbar palsy]] and descending paralysis, lack of fever, and clear senses and mental status ("clear sensorium").<ref name=outreakid>{{cite web|url=http://www.outbreakid.com/bioterrorism.htm |url-status=dead |archive-url=https://web.archive.org/web/20120402234631/http://www.outbreakid.com/bioterrorism.htm |archive-date=2 April 2012 |title=Botulism |website=OutbreakID.com}}</ref>

=== Infant botulism ===
[[File:Infant botulism patient.jpeg|thumb|upright|An infant with botulism. Despite not being asleep or sedated, he cannot open his eyes or move; he also has a weak cry.]]

Infant botulism (also referred to as [[floppy baby syndrome]]) was first recognized in 1976, and is the most common form of botulism in the United States. Infants are susceptible to infant botulism in the first year of life, with more than 90% of cases occurring in infants younger than six months.<ref name="SSAIBchap">{{cite book | vauthors = Arnon SS |chapter-url=http://www.infantbotulism.org/readings/ibchap.pdf |chapter=Infant Botulism | veditors = Feigin RD, Cherry JD, Demmler GJ, Kaplan SL |title=Textbook of Pediatric Infectious Diseases |edition=5th |location=Philadelphia |publisher=WB Saunders |date=2004 |pages=1758–66 |url-status=live |archive-url=https://web.archive.org/web/20110726180149/http://www.infantbotulism.org/readings/ibchap.pdf |archive-date=26 July 2011 }}</ref> Infant botulism results from the ingestion of the [[Clostridium botulinum|''C. botulinum'']] spores, and subsequent colonization of the small intestine. The infant gut may be colonized when the composition of the [[gut flora|intestinal microflora]] (normal flora) is insufficient to competitively inhibit the growth of ''C. botulinum'' and levels of bile acids (which normally inhibit [[Clostridia|clostridial]] growth) are lower than later in life.<ref name=Caya2004>{{cite journal |last1=Caya |first1=James G. |last2=Agni |first2=Rashmi |last3=Miller |first3=Joan E. |title=Clostridium botulinum and the Clinical Laboratorian: A Detailed Review of Botulism, Including Biological Warfare Ramifications of Botulinum Toxin |journal=Archives of Pathology & Laboratory Medicine |date=June 2004 |volume=128 |issue=6 |pages=653–662 |doi=10.5858/2004-128-653-CBATCL |pmid=15163234 }}</ref>

The growth of the spores releases [[botulinum toxin]], which is then absorbed into the bloodstream and taken throughout the body, causing paralysis by blocking the release of [[acetylcholine]] at the [[neuromuscular junction]]. Typical symptoms of infant botulism include constipation, lethargy, weakness, difficulty feeding, and an altered cry, often progressing to a complete descending [[flaccid paralysis]]. Although constipation is usually the first symptom of infant botulism, it is commonly overlooked.<ref name="Infant Botulism">{{cite web|url=http://kidshealth.org/en/parents/botulism.html|title=Infant Botulism|website=kidshealth.org|access-date=28 September 2016|url-status=live|archive-url=https://web.archive.org/web/20161007110000/http://kidshealth.org/en/parents/botulism.html|archive-date=7 October 2016}}</ref>

[[Honey]] is a known dietary reservoir of ''[[Clostridium botulinum|C. botulinum]]'' spores and has been linked to infant botulism. For this reason, honey is not recommended for infants less than one year of age.<ref name=Caya2004 /> Most cases of infant botulism, however, are thought to be caused by acquiring the spores from the natural environment. ''[[Clostridium botulinum]]'' is a ubiquitous soil-dwelling bacterium. Many infant botulism patients have been demonstrated to live near a construction site or an area of soil disturbance.<ref name="Infant botulism literature review">{{cite journal | vauthors = Domingo RM, Haller JS, Gruenthal M | title = Infant botulism: two recent cases and literature review | journal = Journal of Child Neurology | volume = 23 | issue = 11 | pages = 1336–46 | date = November 2008 | pmid = 18984848 | doi = 10.1177/0883073808318200 }}</ref>

Infant botulism has been reported in 49 of 50 US states (all except for Rhode Island),<ref name="SSAIBchap" /> and cases have been recognized in 26 countries on five continents.<ref name="globalIB">{{cite journal | vauthors = Koepke R, Sobel J, Arnon SS | title = Global occurrence of infant botulism, 1976-2006 | journal = Pediatrics | volume = 122 | issue = 1 | pages = e73-82 | date = July 2008 | pmid = 18595978 | doi = 10.1542/peds.2007-1827 }}</ref>

=== Complications ===
Infant botulism has no long-term side effects.{{citation needed|date=December 2022}}

Botulism can result in death due to [[respiration (physiology)|respiratory]] failure. However, in the past 50 years, the proportion of patients with botulism who die has fallen from about 50% to 7% due to improved supportive care. A patient with severe botulism may require [[mechanical ventilation]] (breathing support through a ventilator) as well as intensive medical and nursing care, sometimes for several months. The person may require rehabilitation therapy after leaving the hospital.<ref>{{cite web |url=https://www.cdc.gov/foodsafety/diseases/clostridium-perfringens.html|title=Prevent Illness From ''C. perfringens'' |access-date=14 June 2016 |publisher=U.S. Centers for Disease Control and Prevention |url-status=live |archive-url=https://web.archive.org/web/20160616152125/http://www.cdc.gov/foodsafety/diseases/clostridium-perfringens.html |archive-date=16 June 2016 }}</ref>