Paratyphoid Fever
Reporting obligation
Individuals who have or may have Paratyphoid fever shall be reported to KFL&A Public Health.
Reportable Disease Notification Form
Epidemiology
Aetiologic agent
Paratyphoid fever is caused by Salmonella enteric subspecies enterica serotype Paratyphi A, B and C
(commonly S. Paratyphi). Note that Salmonella Paratyphi B variant Java should be reported as a case of salmonellosis, not paratyphoid fever.
Clinical presentation
Paratyphoid fever is a systemic bacterial disease which usually presents with fever, headache, malaise, anorexia, and diminished frequency of stool which is more common than diarrhea, plus bradycardia, enlargement of spleen and rose spots on trunk in 25% of white-skinned patients. The clinical picture varies from mild illness with low-grade fever to severe clinical disease with abdominal discomfort and multiple complications. Peyer patches in the ileum can ulcerate with intestinal hemorrhage or perforation, especially late in untreated cases.
Modes of transmission
Fecal-oral route. Transmitted via ingestion of food and water contaminated by feces and urine of cases and carriers; also by ingestion of contaminated milk, raw fruit and vegetables and shellfish harvested from contaminated water. Flies may be vectors. Person-to-person transmission has also been documented.
Incubation period
1 to 10 days.
Period of communicability
Communicable as long as organisms are excreted; from the appearance of prodromal symptoms, throughout illness and for periods of up to two weeks after onset.
Risk and susceptibility
Susceptibility is general and is increased in individuals with gastric achloryhdria and possibly in those who are HIV positive. Relative specific immunity follows recovery from clinical disease and inapparent infection. Travellers should be referred to travel clinics to assess their personal risk and appropriate preventive measures.
Diagnosis and laboratory testing
Laboratory confirmation of infection with or without clinically compatible signs and symptoms (characterized by insidious onset of sustained fever, headache, malaise, anorexia, relative bradycardia, constipation or diarrhea):
- Isolation of Salmonella Paratyphi A, B, or C (excluding S. Paratyphi B variant Java) from an appropriate clinical specimen (e.g., sterile site, blood, stool, urine).
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Treatment and case management
Treatment with antibiotics and follow up is under the direction of the attending health care provider. Where possible, physicians should be encouraged to request antibiotic sensitivity testing due to resistant strains. With appropriate antibiotic treatment, infected individuals with typhoid or paratyphoid fever usually recover within ten to 14 days. Educate the case about transmission of infection and proper hand hygiene.
Exclude all cases (regardless of symptoms) of S. Paratyphi from food handling, healthcare and daycare activities until provision of 3 consecutive negative stool samples collected at least 48 hours apart and at least 48 hours after completion of antibiotic treatment (for ciprofloxacin) or at least 2 weeks after completion of antibiotic treatment (for ceftriaxone and azithromycin). Close contacts should be seen by their health care provider and screened for illness (stool specimens sent for testing). If after 6 samples, a case continues to test positive, then he or she may be in an excreter state.
Additional readings
References:
Ministry of Health and Long Term Care, Infectious Diseases Protocol
Adapted with permission from Leeds, Grenville & Lanark District Health Unit