Question: solve systems of differential equations in maple

eq1 := {
diff(S_h(t),t)= mu_h*(N_h-S_h(t))-(bi_h*b)/(N_h+m)*S_h(t)*I_v(t),
diff(I_h(t),t)=(bi_h*b)/(N_h+m)*S_h(t)*I_v(t)-(mu_h+ga)*I_h(t),
diff(R_h(t),t)=ga*I_h(t)-mu_h*R_h(t),
diff(S_v(t),t)=A-(bi_v*b)/(N_h+m)*S_h(t)*I_h(t)-mu_v*S_v(t),
diff(I_v(t),t)=(bi_v*b)/(N_h+m)*S_v(t)*I_h(t)-mu_h*I_h(t),
mu_h=0.0000457,mu_v=0.25,b=1,ga=0.167,
bi_h=0.4, bi_v=0.4,m=0,N_h=10000,A=5000,
S_h(0)=10000,
I_h(0)=1,R_h(0)=0,S_v(0)=10000,I_v(0)=1
};

sol1:=dsolve(eq1,{S_h(t),I_h(t),R_h(t),S_v(t),I_v(t)}, type=numeric);

Error, (in dsolve/numeric/process_input) invalid specification of initial conditions, got {A = 5000, N_h = 10000, b = 1, ga = .167, m = 0, bi_h = .4, bi_v = .4, mu_h = 0.457e-4, mu_v = .25}

how to rectify this can any one give me answer to me...............