Over-dispersed Trypanosoma cruzi parasite load in sylvatic and domestic mammals and humans from northeastern Argentina

Table 3 Estimated parameters for three non-linear models of host infectiousness for domestic and sylvatic mammals infected with Trypanosoma cruzi

Model	No. of hosts	Model parameters (standard error)
Model	No. of hosts	df	B1^a	B2^b	Xmid^c	scal^c	AIC
Domestic hosts
1	171	167	0.76 (0.04)	0.17 (0.03)	NA	NA	− 94.69
2	171	168	NA^d	0.10 (0.01)	NA	NA	− 70.17
Logistic	171	167	NA	NA	11.30 (1.14)	7.19 (1.88)	− 66.69
Sylvatic hosts
1	23	20	0.91 (0.04)	0.36 (0.10)	NA	NA	− 16.53
2	23	21	NA	0.48 (0.12)	NA	NA	− 14.34
Logistic	23	21	NA	NA	10.00 (7.07)	22.00 (10.86)	9.63

AIC Akaike’s information criterion
^a B1 is the probability that a vector becomes infected
^b B2 is the probability that a host with a parasite load of one parasite per milliliter (1 Pe/ml) infects a vector
^c In the logistic model, xmid is the inflection point on the curve and scal is a growth scale
^dNA: Does not apply. The parameter was not included in the model

ISSN: 1756-3305