Getting rid of lingering odours can sometimes be difficult, especially if the odour is caused by an animal such as a mouse that died. But with a little bit of forethought and planning, getting rid of even the nastiest odours can be possible in such a way that actually gets rid of the smell rather than masks it. Utilising the surroundings to encourage the odour to filter out of the room can be helpful, as can simple odour removers that you can usually find in your pantry.
Make sure that any windows in the room where the mouse died are left open for at least a week. The longer they remain open, the quicker the smell will filter out of the room. You might also want to consider putting a fan in the room around where the dead mouse was found to encourage the odour to leave the room faster. Placing the fan behind where the dead mouse was found and pointing it in the direction of the nearest window helps speed up this process.
A small cup of baking soda placed beside where you found the dead mouse will absorb and neutralise the odour, rather than merely mask it as most commercial air fresheners do.
Lime treatments are better than many air fresheners, not to mention less of a hazard to the environment. Because of how quickly it destroys odours, you can save yourself money by opting for a lime treatment rather than stocking up on air fresheners. In addition, performing a lime treatment can drastically decrease the amount of pathogens present in the area should the dead mouse have died due to disease. Furthermore, you won't have to worry about getting rid of any of the surroundings that may otherwise have been tainted by harsh chemicals if you opt for a lime treatment.