Heavy cryptosporidial infections in children in northeast Brazil: comparison of Cryptosporidium hominis and Cryptosporidium parvum.
Cryptosporidium is an important cause of infectious diarrhoea worldwide, but little is known about the course of illness when infected with different species. Over a period of 5 years, Cryptosporidium was identified in the stools of 58 of 157 children prospectively followed from birth in an urban slum (favela) in northeast Brazil. Forty isolates were available for quantification and 42 for speciation (24 Cryptosporidium hominis and 18 C. parvum). Children with C. hominis shed significantly more oocysts/ml of stool (3.5 x 10(6) vs. 1.7 x 10(6)perml; P=0.001), and oocyst counts were higher among symptomatic children (P=0.002). Heavier C. parvum shedding was significantly associated with symptoms (P=0.004), and symptomatic C. parvum-infected children were significantly more likely than asymptomatic children to be lactoferrin-positive (P=0.004). Height-for-age (HAZ) Z-scores showed significant declines within 3 months of infection for children infected with either C. hominis (P=0.028) or C. parvum (P=0.001). However, in the 3-6 month period following infection, only C. hominis-infected children continued to demonstrate declining HAZ score and asymptomatic children showed even greater decline (P=0.01). Cryptosporidium hominis is more common than C. parvum in favela children and is associated with heavier infections and greater growth shortfalls, even in the absence of symptoms.
Bushen
Oluma Y
OY
Center for Global Health, Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA.
Kohli
Anita
A
Pinkerton
Relana C
RC
Dupnik
Kate
K
Newman
Robert D
RD
Sears
Cynthia L
CL
Fayer
Ronald
R
Lima
Aldo A M
AA
Guerrant
Richard L
RL
D000818:Animals; D000886:Anthropometry; D002675:Child, Preschool; D003457:Cryptosporidiosis / Q000469:parasitology*; D003458:Cryptosporidium / Q000145:classification* / Q000302:isolation & purification / Q000502:physiology; D016785:Cryptosporidium parvum / Q000302:isolation & purification / Q000502:physiology; D003968:Diarrhea, Infantile / Q000469:parasitology; D005243:Feces / Q000737:chemistry / Q000469:parasitology; D006790:Host-Parasite Interactions; D006801:Humans; D007223:Infant; D007781:Lactoferrin / Q000032:analysis; D009752:Nutritional Status; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D011446:Prospective Studies; D013045:Species Specificity; D014504:Urban Health / Q000706:statistics & numerical data
D007781:Lactoferrin