Diphtheria

Diphtheria
An adherent, dense, grey pseudomembrane covering the tonsils is classically seen in diphtheria.
SpecialtyInfectious disease
SymptomsSore throat, fever, barking cough[1]
ComplicationsMyocarditis, Peripheral neuropathy, Proteinuria
Usual onset2–5 days post-exposure[2]
CausesCorynebacterium diphtheriae (spread by direct contact and through the air)[2]
Diagnostic methodExamination of throat, culture[1]
PreventionDiphtheria vaccine[2]
TreatmentAntibiotics, tracheostomy[2]
Prognosis5–10% risk of death
Frequency4,500 (reported 2015)[3]
Deaths2,100 (2015)[4]

Diphtheria is an infection caused by the bacterium Corynebacterium diphtheriae.[2] Most infections are asymptomatic or have a mild clinical course, but in some outbreaks, the mortality rate approaches 10%.[1] Signs and symptoms may vary from mild to severe,[1] and usually start two to five days after exposure.[2] Symptoms often develop gradually, beginning with a sore throat and fever.[1] In severe cases, a grey or white patch develops in the throat,[2][1] which can block the airway, and create a barking cough similar to what is observed in croup.[1] The neck may also swell, in part due to the enlargement of the facial lymph nodes.[2] Diphtheria can also involve the skin, eyes, or genitals, and can cause[2][1] complications, including myocarditis (which in itself can result in an abnormal heart rate), inflammation of nerves (which can result in paralysis), kidney problems, and bleeding problems due to low levels of platelets.[2]

Diphtheria is usually spread between people by direct contact, through the air, or through contact with contaminated objects.[2][5] Asymptomatic transmission and chronic infection are also possible.[2] Different strains of C. diphtheriae are the main cause in the variability of lethality,[2] as the lethality and symptoms themselves are caused by the exotoxin produced by the bacteria.[1] Diagnosis can often be made based on the appearance of the throat with confirmation by microbiological culture.[1] Previous infection may not protect against reinfection.[1]

A diphtheria vaccine is effective for prevention, and is available in a number of formulations.[2] Three or four doses, given along with tetanus vaccine and pertussis vaccine, are recommended during childhood.[2] Further doses of the diphtheria–tetanus vaccine are recommended every ten years.[2] Protection can be verified by measuring the antitoxin level in the blood.[2] Diphtheria can be prevented in those exposed, as well as treated with the antibiotics erythromycin or benzylpenicillin.[2]In severe cases a tracheotomy is sometimes needed to open the airway.[1]

In 2015, 4,500 cases were officially reported worldwide, down from nearly 100,000 in 1980.[3] About a million cases a year are believed to have occurred before the 1980s.[1] Diphtheria currently occurs most often in sub-Saharan Africa, South Asia, and Indonesia.[1][6] In 2015, it resulted in 2,100 deaths, down from 8,000 deaths in 1990.[4][7] In areas where it is still common, children are most affected.[1] It is rare in the developed world due to widespread vaccination, but can re-emerge if vaccination rates decrease.[1][8] In the United States, 57 cases were reported between 1980 and 2004.[2] Death occurs in 5–10% of those diagnosed.[2] The disease was first described in the 5th century BC by Hippocrates.[2] The bacterium was identified in 1882 by Edwin Klebs.[2]

  1. ^ a b c d e f g h i j k l m n o p "Diphtheria vaccine" (PDF). Wkly Epidemiol Rec. 81 (3): 24–32. 20 January 2006. PMID 16671240. Archived (PDF) from the original on 6 June 2015.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v Atkinson, William (May 2012). Diphtheria Epidemiology and Prevention of Vaccine-Preventable Diseases (12 ed.). Public Health Foundation. pp. 215–230. ISBN 9780983263135. Archived from the original on 15 September 2016.
  3. ^ a b "Diphtheria". who.int. 3 September 2014. Archived from the original on 2 April 2015. Retrieved 27 March 2015.
  4. ^ a b GBD 2015 Mortality and Causes of Death Collaborators (8 October 2016). "Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: a systematic analysis for the Global Burden of Disease Study 2015". Lancet. 388 (10053): 1459–1544. doi:10.1016/s0140-6736(16)31012-1. PMC 5388903. PMID 27733281.
  5. ^ Kowalski, Wladyslaw (2012). Hospital airborne infection control. Boca Raton, Florida: CRC Press. p. 54. ISBN 9781439821961. Archived from the original on 21 December 2016.
  6. ^ Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases (8 ed.). Elsevier Health Sciences. 2014. p. 2372. ISBN 9780323263733. Archived from the original on 21 December 2016.
  7. ^ GBD 2013 Mortality and Causes of Death Collaborators (17 December 2014). "Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013". Lancet. 385 (9963): 117–71. doi:10.1016/S0140-6736(14)61682-2. PMC 4340604. PMID 25530442.
  8. ^ Al, A. E. Paniz-Mondolfi et (2019). "Resurgence of Vaccine-Preventable Diseases in Venezuela as a Regional Public Health Threat in the Americas – Volume 25, Number 4 – April 2019 – Emerging Infectious Diseases journal – CDC". Emerging Infectious Diseases. 25 (4): 625–632. doi:10.3201/eid2504.181305. PMC 6433037. PMID 30698523.