Apply Transfer Function in Continuous Domain in Matlab
One approach could be to get a finite number of values of the impulse response of your system using the 'impulse' function, and then convolve this with your signal (taking care of the actual sampling frequency you are using).

% sampling time of 1ms, 20s of time signal 
T = 0.001;
t = 0:T:20;

% low pass filter with cutoff frequency at sine frequency
wo = 1;
x = sin(wo*t);
s = tf('s');
H = wo / (s+wo);

% get the h(t)
h = impulse(H,t);

% plot the output
plot(t,x);
y = T*conv(x,h);
y = y(1:length(x));
hold all;
plot(t,y)